2006-09-13 18:14:29 +02:00
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.\" $MirOS: src/bin/mksh/mksh.1,v 1.59 2006/09/13 16:14:29 tg Exp $
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2006-08-01 16:09:20 +02:00
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.\" $OpenBSD: ksh.1,v 1.116 2006/07/26 10:13:25 jmc Exp $
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2005-06-08 23:51:22 +02:00
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.\"
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2006-09-13 18:14:29 +02:00
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.Dd September 13, 2006
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2005-05-23 05:06:10 +02:00
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.Dt MKSH 1
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2006-01-27 11:59:30 +01:00
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.Os MirBSD
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2005-05-23 05:06:10 +02:00
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.Sh NAME
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2006-07-21 23:47:43 +02:00
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.Nm mksh ,
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.Nm sh
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2005-07-04 14:34:24 +02:00
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.Nd MirBSD Korn shell
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2005-05-23 05:06:10 +02:00
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.Sh SYNOPSIS
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.Nm
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.Bk -words
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.Op Fl +abCefhiklmnpruvXx
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.Op Fl T Ar /dev/ttyCn
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.Op Fl +o Ar option
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.Oo Fl c Ar string \*(Ba Fl s \*(Ba
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.Ar \ file\ \&
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.Op Ar argument ... Oc
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.Ek
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.Sh DESCRIPTION
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.Nm
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is a command interpreter intended for both interactive and shell
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script use.
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Its command language is a superset of the
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.Xr sh C
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shell language and largely compatible to the original Korn shell.
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.Pp
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The options are as follows:
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.Bl -tag -width Ds
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.It Fl c Ar string
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.Nm
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will execute the command(s) contained in
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.Ar string .
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.It Fl i
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Interactive shell.
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A shell is
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.Dq interactive
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if this
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option is used or if both standard input and standard error are attached
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to a
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.Xr tty 4 .
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An interactive shell has job control enabled, ignores the
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.Dv SIGINT ,
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.Dv SIGQUIT ,
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and
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.Dv SIGTERM
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signals, and prints prompts before reading input (see the
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.Ev PS1
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and
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.Ev PS2
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parameters).
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For non-interactive shells, the
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.Ic trackall
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option is on by default (see the
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.Ic set
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command below).
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.It Fl l
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Login shell.
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If the basename the shell is called with (i.e. argv[0])
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starts with
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.Ql -
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or if this option is used,
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the shell is assumed to be a login shell and the shell reads and executes
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the contents of
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.Pa /etc/profile
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and
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.Pa $HOME/.profile
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if they exist and are readable.
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.It Fl p
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Privileged shell.
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A shell is
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.Dq privileged
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if this option is used
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or if the real user ID or group ID does not match the
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effective user ID or group ID (see
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.Xr getuid 2
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and
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.Xr getgid 2 ) .
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A privileged shell does not process
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.Pa $HOME/.profile
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nor the
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.Ev ENV
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2006-05-08 13:42:36 +02:00
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parameter or
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.Pa $HOME/.mkshrc
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(see below).
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2005-05-23 05:06:10 +02:00
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Instead, the file
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.Pa /etc/suid_profile
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is processed.
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Clearing the privileged option causes the shell to set
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its effective user ID (group ID) to its real user ID (group ID).
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.It Fl r
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Restricted shell.
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A shell is
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.Dq restricted
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if this
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2005-07-04 13:57:55 +02:00
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option is used.
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2005-05-23 05:06:10 +02:00
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The following restrictions come into effect after the shell processes any
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profile and
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.Ev ENV
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files:
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.Pp
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.Bl -bullet -compact
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.It
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The
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.Ic cd
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command is disabled.
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.It
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The
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.Ev SHELL ,
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.Ev ENV ,
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and
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.Ev PATH
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parameters cannot be changed.
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.It
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Command names can't be specified with absolute or relative paths.
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.It
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The
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.Fl p
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option of the built-in command
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.Ic command
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can't be used.
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.It
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Redirections that create files can't be used (i.e.\&
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.Ql \*(Gt ,
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.Ql \*(Gt\*(Ba ,
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.Ql \*(Gt\*(Gt ,
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.Ql \*(Lt\*(Gt ) .
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.El
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.It Fl s
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The shell reads commands from standard input; all non-option arguments
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are positional parameters.
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.It Fl T Ar tty
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Spawn
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.Nm
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on the
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.Xr tty 4
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device given.
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Superuser only.
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.El
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.Pp
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In addition to the above, the options described in the
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.Ic set
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built-in command can also be used on the command line:
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both
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.Op Fl +abCefhkmnuvXx
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and
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.Op Fl +o Ar option
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can be used for single letter or long options, respectively.
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.Pp
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If neither the
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.Fl c
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nor the
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.Fl s
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option is specified, the first non-option argument specifies the name
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of a file the shell reads commands from.
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If there are no non-option
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arguments, the shell reads commands from the standard input.
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The name of the shell (i.e. the contents of $0)
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is determined as follows: if the
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.Fl c
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option is used and there is a non-option argument, it is used as the name;
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if commands are being read from a file, the file is used as the name;
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otherwise, the basename the shell was called with (i.e. argv[0]) is used.
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.Pp
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If the
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.Ev ENV
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2006-06-21 21:27:35 +02:00
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parameter is set when an interactive shell starts (or, in the case of login
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shells, after any profiles are processed), its value is subjected to
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parameter, command, arithmetic, and tilde
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2005-05-23 05:06:10 +02:00
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.Pq Sq ~
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substitution and the resulting file
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(if any) is read and executed.
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2006-05-08 13:42:36 +02:00
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If the
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.Ev ENV
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2006-05-08 13:59:41 +02:00
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variable is unset or empty, the file
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2006-05-08 13:42:36 +02:00
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.Pa $HOME/.mkshrc
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is read and processed like above instead, leaving
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.Ev ENV
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unset in the shell environment.
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This processing does not occur if
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.Ev ENV
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is set to a non-existing filename.
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2005-05-23 05:06:10 +02:00
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.Pp
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The exit status of the shell is 127 if the command file specified on the
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command line could not be opened, or non-zero if a fatal syntax error
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occurred during the execution of a script.
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In the absence of fatal errors,
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the exit status is that of the last command executed, or zero, if no
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command is executed.
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.Ss Command syntax
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2005-05-26 01:31:08 +02:00
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The shell begins parsing its input by removing any backslash-newline
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combinations, then breaking it into
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2005-05-23 05:06:10 +02:00
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.Em words .
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2006-01-30 13:37:24 +01:00
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Words (which are sequences of characters) are delimited by unquoted whitespace
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2005-05-23 05:06:10 +02:00
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characters (space, tab, and newline) or meta-characters
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.Po
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.Ql \*(Lt ,
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.Ql \*(Gt ,
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.Ql \*(Ba ,
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.Ql \&; ,
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.Ql ( ,
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.Ql \&) ,
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and
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.Ql &
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.Pc .
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Aside from delimiting words, spaces and tabs are ignored, while newlines
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usually delimit commands.
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The meta-characters are used in building the following
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.Em tokens :
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.Ql \*(Lt ,
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.Ql \*(Lt& ,
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.Ql \*(Lt\*(Lt ,
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.Ql \*(Gt ,
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.Ql \*(Gt& ,
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.Ql \*(Gt\*(Gt ,
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etc. are used to specify redirections (see
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.Sx Input/output redirection
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below);
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.Ql \*(Ba
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is used to create pipelines;
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.Ql \*(Ba&
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is used to create co-processes (see
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.Sx Co-processes
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below);
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.Ql \&;
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is used to separate commands;
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.Ql &
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is used to create asynchronous pipelines;
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.Ql &&
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and
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2006-01-27 11:58:36 +01:00
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.Ql \*(Ba\*(Ba
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2005-05-23 05:06:10 +02:00
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are used to specify conditional execution;
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.Ql ;;
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is used in
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.Ic case
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statements;
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.Ql (( .. ))
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is used in arithmetic expressions;
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and lastly,
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.Ql \&( .. )\&
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is used to create subshells.
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.Pp
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Whitespace and meta-characters can be quoted individually using a backslash
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.Pq Sq \e ,
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or in groups using double
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.Pq Sq \&"
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or single
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.Pq Sq '
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quotes.
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Note that the following characters are also treated specially by the
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shell and must be quoted if they are to represent themselves:
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.Ql \e ,
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.Ql \&" ,
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.Ql ' ,
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.Ql # ,
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.Ql $ ,
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.Ql ` ,
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.Ql ~ ,
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.Ql { ,
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.Ql } ,
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.Ql * ,
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.Ql \&? ,
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and
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.Ql [ .
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The first three of these are the above mentioned quoting characters (see
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.Sx Quoting
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below);
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.Ql # ,
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if used at the beginning of a word, introduces a comment \(em everything after
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the
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.Ql #
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up to the nearest newline is ignored;
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.Ql $
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is used to introduce parameter, command, and arithmetic substitutions (see
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.Sx Substitution
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below);
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.Ql `
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introduces an old-style command substitution (see
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.Sx Substitution
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below);
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.Ql ~
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begins a directory expansion (see
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.Sx Tilde expansion
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below);
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.Ql {
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and
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.Ql }
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delimit
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.Xr csh 1 Ns -style
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alterations (see
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.Sx Brace expansion
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below);
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and finally,
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.Ql * ,
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.Ql \&? ,
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and
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.Ql [
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are used in file name generation (see
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.Sx File name patterns
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below).
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.Pp
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As words and tokens are parsed, the shell builds commands, of which there
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are two basic types:
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.Em simple-commands ,
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typically programmes that are executed, and
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.Em compound-commands ,
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such as
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.Ic for
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and
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.Ic if
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statements, grouping constructs, and function definitions.
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.Pp
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A simple-command consists of some combination of parameter assignments
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(see
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.Sx Parameters
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below),
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input/output redirections (see
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.Sx Input/output redirections
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below),
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and command words; the only restriction is that parameter assignments come
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before any command words.
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The command words, if any, define the command
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that is to be executed and its arguments.
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The command may be a shell built-in command, a function,
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or an external command
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(i.e. a separate executable file that is located using the
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.Ev PATH
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parameter; see
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.Sx Command execution
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below).
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Note that all command constructs have an exit status: for external commands,
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this is related to the status returned by
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.Xr wait 2
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(if the command could not be found, the exit status is 127; if it could not
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be executed, the exit status is 126); the exit status of other command
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constructs (built-in commands, functions, compound-commands, pipelines, lists,
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etc.) are all well-defined and are described where the construct is
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described.
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The exit status of a command consisting only of parameter
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assignments is that of the last command substitution performed during the
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parameter assignment or 0 if there were no command substitutions.
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.Pp
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Commands can be chained together using the
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2006-01-27 11:58:36 +01:00
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.Ql \*(Ba
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2005-05-23 05:06:10 +02:00
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token to form pipelines, in which the standard output of each command but the
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last is piped (see
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.Xr pipe 2 )
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to the standard input of the following command.
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The exit status of a pipeline is that of its last command.
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A pipeline may be prefixed by the
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.Ql \&!
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2006-01-30 13:37:24 +01:00
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reserved word which causes the exit status of the pipeline to be logically
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2005-05-23 05:06:10 +02:00
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complemented: if the original status was 0, the complemented status will be 1;
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if the original status was not 0, the complemented status will be 0.
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.Pp
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.Em Lists
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of commands can be created by separating pipelines by any of the following
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tokens:
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.Ql && ,
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2006-01-27 11:58:36 +01:00
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.Ql \*(Ba\*(Ba ,
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2005-05-23 05:06:10 +02:00
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.Ql & ,
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2006-01-27 11:58:36 +01:00
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.Ql \*(Ba& ,
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2005-05-23 05:06:10 +02:00
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and
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.Ql \&; .
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The first two are for conditional execution:
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.Dq Ar cmd1 No && Ar cmd2
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executes
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.Ar cmd2
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only if the exit status of
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.Ar cmd1
|
|
|
|
is zero;
|
2006-01-27 11:58:36 +01:00
|
|
|
.Ql \*(Ba\*(Ba
|
2005-05-23 05:06:10 +02:00
|
|
|
is the opposite \(em
|
|
|
|
.Ar cmd2
|
|
|
|
is executed only if the exit status of
|
|
|
|
.Ar cmd1
|
|
|
|
is non-zero.
|
|
|
|
.Ql &&
|
|
|
|
and
|
2006-01-27 11:58:36 +01:00
|
|
|
.Ql \*(Ba\*(Ba
|
2005-05-23 05:06:10 +02:00
|
|
|
have equal precedence which is higher than that of
|
|
|
|
.Ql & ,
|
2006-01-27 11:58:36 +01:00
|
|
|
.Ql \*(Ba& ,
|
2005-05-23 05:06:10 +02:00
|
|
|
and
|
|
|
|
.Ql \&; ,
|
|
|
|
which also have equal precedence.
|
|
|
|
Note that the
|
|
|
|
.Ql &&
|
|
|
|
and
|
2006-01-27 11:58:36 +01:00
|
|
|
.Ql \*(Ba\*(Ba
|
2005-05-23 05:06:10 +02:00
|
|
|
operators are
|
|
|
|
.Qq left-associative .
|
|
|
|
For example, both of these commands will print only
|
|
|
|
.Qq bar :
|
|
|
|
.Bd -literal -offset indent
|
2006-01-27 11:58:36 +01:00
|
|
|
$ false && echo foo \*(Ba\*(Ba echo bar
|
|
|
|
$ true \*(Ba\*(Ba echo foo && echo bar
|
2005-05-23 05:06:10 +02:00
|
|
|
.Ed
|
|
|
|
.Pp
|
|
|
|
The
|
|
|
|
.Ql &
|
|
|
|
token causes the preceding command to be executed asynchronously; that is,
|
|
|
|
the shell starts the command but does not wait for it to complete (the shell
|
|
|
|
does keep track of the status of asynchronous commands; see
|
|
|
|
.Sx Job control
|
|
|
|
below).
|
|
|
|
When an asynchronous command is started when job control is disabled
|
|
|
|
(i.e. in most scripts), the command is started with signals
|
|
|
|
.Dv SIGINT
|
|
|
|
and
|
|
|
|
.Dv SIGQUIT
|
|
|
|
ignored and with input redirected from
|
|
|
|
.Pa /dev/null
|
|
|
|
(however, redirections specified in the asynchronous command have precedence).
|
|
|
|
The
|
2006-01-27 11:58:36 +01:00
|
|
|
.Ql \*(Ba&
|
2005-05-23 05:06:10 +02:00
|
|
|
operator starts a co-process which is a special kind of asynchronous process
|
|
|
|
(see
|
|
|
|
.Sx Co-processes
|
|
|
|
below).
|
|
|
|
Note that a command must follow the
|
|
|
|
.Ql &&
|
|
|
|
and
|
2006-01-27 11:58:36 +01:00
|
|
|
.Ql \*(Ba\*(Ba
|
2005-05-23 05:06:10 +02:00
|
|
|
operators, while it need not follow
|
|
|
|
.Ql & ,
|
2006-01-27 11:58:36 +01:00
|
|
|
.Ql \*(Ba& ,
|
2005-05-23 05:06:10 +02:00
|
|
|
or
|
|
|
|
.Ql \&; .
|
|
|
|
The exit status of a list is that of the last command executed, with the
|
|
|
|
exception of asynchronous lists, for which the exit status is 0.
|
|
|
|
.Pp
|
|
|
|
Compound commands are created using the following reserved words.
|
|
|
|
These words
|
|
|
|
are only recognised if they are unquoted and if they are used as the first
|
|
|
|
word of a command (i.e. they can't be preceded by parameter assignments or
|
|
|
|
redirections):
|
|
|
|
.Bd -literal -offset indent
|
|
|
|
case else function then !
|
|
|
|
do esac if time [[
|
|
|
|
done fi in until {
|
|
|
|
elif for select while }
|
|
|
|
.Ed
|
|
|
|
.Pp
|
|
|
|
.Sy Note :
|
|
|
|
Some shells (but not this one) execute control structure commands in a
|
|
|
|
subshell when one or more of their file descriptors are redirected, so any
|
|
|
|
environment changes inside them may fail.
|
|
|
|
To be portable, the
|
|
|
|
.Ic exec
|
|
|
|
statement should be used instead to redirect file descriptors before the
|
|
|
|
control structure.
|
|
|
|
.Pp
|
|
|
|
In the following compound command descriptions, command lists (denoted as
|
|
|
|
.Em list )
|
|
|
|
that are followed by reserved words must end with a semicolon, a newline, or
|
|
|
|
a (syntactically correct) reserved word.
|
|
|
|
For example, the following are all valid:
|
|
|
|
.Bd -literal -offset indent
|
|
|
|
$ { echo foo; echo bar; }
|
2005-05-26 01:31:08 +02:00
|
|
|
$ { echo foo; echo bar\*(Ltnewline\*(Gt}
|
2005-05-23 05:06:10 +02:00
|
|
|
$ { { echo foo; echo bar; } }
|
|
|
|
.Ed
|
|
|
|
.Pp
|
|
|
|
This is not valid:
|
|
|
|
.Pp
|
|
|
|
.Dl $ { echo foo; echo bar }
|
|
|
|
.Bl -tag -width Ds
|
|
|
|
.It Pq Ar list
|
|
|
|
Execute
|
|
|
|
.Ar list
|
|
|
|
in a subshell.
|
|
|
|
There is no implicit way to pass environment changes from a
|
|
|
|
subshell back to its parent.
|
|
|
|
.It { Ar list ; No }
|
|
|
|
Compound construct;
|
|
|
|
.Ar list
|
|
|
|
is executed, but not in a subshell.
|
|
|
|
Note that
|
|
|
|
.Ql {
|
|
|
|
and
|
|
|
|
.Ql }
|
|
|
|
are reserved words, not meta-characters.
|
|
|
|
.It Xo case Ar word No in
|
|
|
|
.Oo Op (
|
|
|
|
.Ar \ pattern
|
|
|
|
.Op \*(Ba Ar pattern
|
|
|
|
.No ... No )
|
|
|
|
.Ar list No ;;\ \& Oc ... esac
|
|
|
|
.Xc
|
|
|
|
The
|
|
|
|
.Ic case
|
|
|
|
statement attempts to match
|
|
|
|
.Ar word
|
|
|
|
against a specified
|
|
|
|
.Ar pattern ;
|
|
|
|
the
|
|
|
|
.Ar list
|
|
|
|
associated with the first successfully matched pattern is executed.
|
|
|
|
Patterns used in
|
|
|
|
.Ic case
|
|
|
|
statements are the same as those used for file name patterns except that the
|
|
|
|
restrictions regarding
|
|
|
|
.Ql \&.
|
|
|
|
and
|
|
|
|
.Ql /
|
|
|
|
are dropped.
|
|
|
|
Note that any unquoted space before and after a pattern is
|
|
|
|
stripped; any space within a pattern must be quoted.
|
|
|
|
Both the word and the
|
|
|
|
patterns are subject to parameter, command, and arithmetic substitution, as
|
|
|
|
well as tilde substitution.
|
|
|
|
For historical reasons, open and close braces may be used instead of
|
|
|
|
.Ic in
|
|
|
|
and
|
|
|
|
.Ic esac
|
|
|
|
e.g.\&
|
|
|
|
.Ic case $foo { *) echo bar; } .
|
|
|
|
The exit status of a
|
|
|
|
.Ic case
|
|
|
|
statement is that of the executed
|
|
|
|
.Ar list ;
|
|
|
|
if no
|
|
|
|
.Ar list
|
|
|
|
is executed, the exit status is zero.
|
|
|
|
.It Xo for Ar name
|
|
|
|
.Oo in Ar word No ... Oc ;
|
|
|
|
.No do Ar list ; No done
|
|
|
|
.Xc
|
|
|
|
For each
|
|
|
|
.Ar word
|
|
|
|
in the specified word list, the parameter
|
|
|
|
.Ar name
|
|
|
|
is set to the word and
|
|
|
|
.Ar list
|
|
|
|
is executed.
|
|
|
|
If
|
|
|
|
.Ic in
|
|
|
|
is not used to specify a word list, the positional parameters
|
|
|
|
($1, $2, etc.)\&
|
|
|
|
are used instead.
|
|
|
|
For historical reasons, open and close braces may be used instead of
|
|
|
|
.Ic do
|
|
|
|
and
|
|
|
|
.Ic done
|
|
|
|
e.g.\&
|
|
|
|
.Ic for i; { echo $i; } .
|
|
|
|
The exit status of a
|
|
|
|
.Ic for
|
|
|
|
statement is the last exit status of
|
|
|
|
.Ar list ;
|
|
|
|
if
|
|
|
|
.Ar list
|
|
|
|
is never executed, the exit status is zero.
|
|
|
|
.It Xo if Ar list ;
|
|
|
|
.No then Ar list ;
|
|
|
|
.Oo elif Ar list ;
|
|
|
|
.No then Ar list ; Oc
|
|
|
|
.No ...
|
|
|
|
.Oo else Ar list ; Oc
|
|
|
|
.No fi
|
|
|
|
.Xc
|
|
|
|
If the exit status of the first
|
|
|
|
.Ar list
|
|
|
|
is zero, the second
|
|
|
|
.Ar list
|
|
|
|
is executed; otherwise, the
|
|
|
|
.Ar list
|
|
|
|
following the
|
|
|
|
.Ic elif ,
|
|
|
|
if any, is executed with similar consequences.
|
|
|
|
If all the lists following the
|
|
|
|
.Ic if
|
|
|
|
and
|
|
|
|
.Ic elif Ns s
|
|
|
|
fail (i.e. exit with non-zero status), the
|
|
|
|
.Ar list
|
|
|
|
following the
|
|
|
|
.Ic else
|
|
|
|
is executed.
|
|
|
|
The exit status of an
|
|
|
|
.Ic if
|
|
|
|
statement is that of non-conditional
|
|
|
|
.Ar list
|
|
|
|
that is executed; if no non-conditional
|
|
|
|
.Ar list
|
|
|
|
is executed, the exit status is zero.
|
|
|
|
.It Xo select Ar name
|
|
|
|
.Oo in Ar word No ... Oc ;
|
|
|
|
.No do Ar list ; No done
|
|
|
|
.Xc
|
|
|
|
The
|
|
|
|
.Ic select
|
|
|
|
statement provides an automatic method of presenting the user with a menu and
|
|
|
|
selecting from it.
|
|
|
|
An enumerated list of the specified
|
|
|
|
.Ar word Ns (s)
|
|
|
|
is printed on standard error, followed by a prompt
|
|
|
|
.Po
|
|
|
|
.Ev PS3: normally
|
|
|
|
.Sq #?\ \&
|
|
|
|
.Pc .
|
|
|
|
A number corresponding to one of the enumerated words is then read from
|
|
|
|
standard input,
|
|
|
|
.Ar name
|
|
|
|
is set to the selected word (or unset if the selection is not valid),
|
|
|
|
.Ev REPLY
|
|
|
|
is set to what was read (leading/trailing space is stripped), and
|
|
|
|
.Ar list
|
|
|
|
is executed.
|
|
|
|
If a blank line (i.e. zero or more
|
|
|
|
.Ev IFS
|
|
|
|
characters) is entered, the menu is reprinted without executing
|
|
|
|
.Ar list .
|
|
|
|
.Pp
|
|
|
|
When
|
|
|
|
.Ar list
|
|
|
|
completes, the enumerated list is printed if
|
|
|
|
.Ev REPLY
|
|
|
|
is
|
|
|
|
.Dv NULL ,
|
|
|
|
the prompt is printed, and so on.
|
|
|
|
This process continues until an end-of-file
|
|
|
|
is read, an interrupt is received, or a
|
|
|
|
.Ic break
|
|
|
|
statement is executed inside the loop.
|
|
|
|
If
|
|
|
|
.Dq in word ...
|
|
|
|
is omitted, the positional parameters are used
|
|
|
|
(i.e. $1, $2, etc.).
|
|
|
|
For historical reasons, open and close braces may be used instead of
|
|
|
|
.Ic do
|
|
|
|
and
|
|
|
|
.Ic done
|
|
|
|
e.g.\&
|
|
|
|
.Ic select i; { echo $i; } .
|
|
|
|
The exit status of a
|
|
|
|
.Ic select
|
|
|
|
statement is zero if a
|
|
|
|
.Ic break
|
|
|
|
statement is used to exit the loop, non-zero otherwise.
|
|
|
|
.It Xo until Ar list ;
|
|
|
|
.No do Ar list ;
|
|
|
|
.No done
|
|
|
|
.Xc
|
|
|
|
This works like
|
|
|
|
.Ic while ,
|
|
|
|
except that the body is executed only while the exit status of the first
|
|
|
|
.Ar list
|
|
|
|
is non-zero.
|
|
|
|
.It Xo while Ar list ;
|
|
|
|
.No do Ar list ;
|
|
|
|
.No done
|
|
|
|
.Xc
|
|
|
|
A
|
|
|
|
.Ic while
|
|
|
|
is a pre-checked loop.
|
|
|
|
Its body is executed as often as the exit status of the first
|
|
|
|
.Ar list
|
|
|
|
is zero.
|
|
|
|
The exit status of a
|
|
|
|
.Ic while
|
|
|
|
statement is the last exit status of the
|
|
|
|
.Ar list
|
|
|
|
in the body of the loop; if the body is not executed, the exit status is zero.
|
|
|
|
.It Xo function Ar name
|
|
|
|
.No { Ar list ; No }
|
|
|
|
.Xc
|
|
|
|
Defines the function
|
|
|
|
.Ar name
|
|
|
|
(see
|
|
|
|
.Sx Functions
|
|
|
|
below).
|
|
|
|
Note that redirections specified after a function definition are
|
|
|
|
performed whenever the function is executed, not when the function definition
|
|
|
|
is executed.
|
|
|
|
.It Ar name Ns () Ar command
|
|
|
|
Mostly the same as
|
|
|
|
.Ic function
|
|
|
|
(see
|
|
|
|
.Sx Functions
|
|
|
|
below).
|
|
|
|
.It Xo Ic time Op Fl p
|
|
|
|
.Op Ar pipeline
|
|
|
|
.Xc
|
|
|
|
The
|
|
|
|
.Ic time
|
|
|
|
reserved word is described in the
|
|
|
|
.Sx Command execution
|
|
|
|
section.
|
|
|
|
.It (( Ar expression No ))
|
|
|
|
The arithmetic expression
|
|
|
|
.Ar expression
|
|
|
|
is evaluated; equivalent to
|
|
|
|
.Dq let expression
|
|
|
|
(see
|
|
|
|
.Sx Arithmetic expressions
|
|
|
|
and the
|
|
|
|
.Ic let
|
|
|
|
command, below).
|
|
|
|
.It Bq Bq Ar \ \&expression\ \&
|
|
|
|
Similar to the
|
|
|
|
.Ic test
|
|
|
|
and
|
|
|
|
.Ic \&[ ... \&]
|
|
|
|
commands (described later), with the following exceptions:
|
|
|
|
.Bl -bullet -offset indent
|
|
|
|
.It
|
|
|
|
Field splitting and file name generation are not performed on arguments.
|
|
|
|
.It
|
|
|
|
The
|
|
|
|
.Fl a
|
|
|
|
.Pq AND
|
|
|
|
and
|
|
|
|
.Fl o
|
|
|
|
.Pq OR
|
|
|
|
operators are replaced with
|
|
|
|
.Ql &&
|
|
|
|
and
|
2006-01-27 11:58:36 +01:00
|
|
|
.Ql \*(Ba\*(Ba ,
|
2005-05-23 05:06:10 +02:00
|
|
|
respectively.
|
|
|
|
.It
|
|
|
|
Operators (e.g.\&
|
|
|
|
.Sq Fl f ,
|
|
|
|
.Sq = ,
|
|
|
|
.Sq \&! )
|
|
|
|
must be unquoted.
|
|
|
|
.It
|
|
|
|
The second operand of the
|
|
|
|
.Sq !=
|
|
|
|
and
|
|
|
|
.Sq =
|
|
|
|
expressions are patterns (e.g. the comparison
|
|
|
|
.Ic [[ foobar = f*r ]]
|
|
|
|
succeeds).
|
|
|
|
.It
|
|
|
|
The single argument form of
|
|
|
|
.Ic test ,
|
|
|
|
which tests if the argument has a non-zero length, is not valid; explicit
|
|
|
|
operators must always be used e.g. instead of
|
|
|
|
.No \&[ Ar str No \&]
|
|
|
|
use
|
|
|
|
.No \&[[ -n Ar str No \&]] .
|
|
|
|
.It
|
|
|
|
Parameter, command, and arithmetic substitutions are performed as expressions
|
|
|
|
are evaluated and lazy expression evaluation is used for the
|
|
|
|
.Ql &&
|
|
|
|
and
|
2006-01-27 11:58:36 +01:00
|
|
|
.Ql \*(Ba\*(Ba
|
2005-05-23 05:06:10 +02:00
|
|
|
operators.
|
|
|
|
This means that in the following statement,
|
|
|
|
.Ic $(\*(Lt foo)
|
|
|
|
is evaluated if and only if the file
|
|
|
|
.Pa foo
|
|
|
|
exists and is readable:
|
|
|
|
.Bd -literal -offset indent
|
|
|
|
$ [[ -r foo && $(\*(Lt foo) = b*r ]]
|
|
|
|
.Ed
|
|
|
|
.El
|
|
|
|
.El
|
|
|
|
.Ss Quoting
|
|
|
|
Quoting is used to prevent the shell from treating characters or words
|
|
|
|
specially.
|
|
|
|
There are three methods of quoting.
|
|
|
|
First,
|
|
|
|
.Ql \e
|
|
|
|
quotes the following character, unless it is at the end of a line, in which
|
|
|
|
case both the
|
|
|
|
.Ql \e
|
|
|
|
and the newline are stripped.
|
|
|
|
Second, a single quote
|
|
|
|
.Pq Sq '
|
|
|
|
quotes everything up to the next single quote (this may span lines).
|
|
|
|
Third, a double quote
|
|
|
|
.Pq Sq \&"
|
|
|
|
quotes all characters, except
|
|
|
|
.Ql $ ,
|
|
|
|
.Ql `
|
|
|
|
and
|
|
|
|
.Ql \e ,
|
|
|
|
up to the next unquoted double quote.
|
|
|
|
.Ql $
|
|
|
|
and
|
|
|
|
.Ql `
|
|
|
|
inside double quotes have their usual meaning (i.e. parameter, command, or
|
|
|
|
arithmetic substitution) except no field splitting is carried out on the
|
|
|
|
results of double-quoted substitutions.
|
|
|
|
If a
|
|
|
|
.Ql \e
|
|
|
|
inside a double-quoted string is followed by
|
|
|
|
.Ql \e ,
|
|
|
|
.Ql $ ,
|
|
|
|
.Ql ` ,
|
|
|
|
or
|
|
|
|
.Ql \&" ,
|
|
|
|
it is replaced by the second character; if it is followed by a newline, both
|
|
|
|
the
|
|
|
|
.Ql \e
|
|
|
|
and the newline are stripped; otherwise, both the
|
|
|
|
.Ql \e
|
|
|
|
and the character following are unchanged.
|
|
|
|
.Ss Aliases
|
|
|
|
There are two types of aliases: normal command aliases and tracked aliases.
|
|
|
|
Command aliases are normally used as a short hand for a long or often used
|
|
|
|
command.
|
|
|
|
The shell expands command aliases (i.e. substitutes the alias name
|
|
|
|
for its value) when it reads the first word of a command.
|
|
|
|
An expanded alias is re-processed to check for more aliases.
|
|
|
|
If a command alias ends in a
|
|
|
|
space or tab, the following word is also checked for alias expansion.
|
|
|
|
The alias expansion process stops when a word that is not an alias is found,
|
|
|
|
when a quoted word is found, or when an alias word that is currently being
|
|
|
|
expanded is found.
|
|
|
|
.Pp
|
|
|
|
The following command aliases are defined automatically by the shell:
|
|
|
|
.Bd -literal -offset indent
|
|
|
|
autoload='typeset -fu'
|
|
|
|
functions='typeset -f'
|
|
|
|
hash='alias -t'
|
|
|
|
history='fc -l'
|
|
|
|
integer='typeset -i'
|
|
|
|
local='typeset'
|
|
|
|
login='exec login'
|
|
|
|
nohup='nohup '
|
|
|
|
r='fc -e -'
|
|
|
|
stop='kill -STOP'
|
|
|
|
suspend='kill -STOP $$'
|
|
|
|
type='whence -v'
|
|
|
|
.Ed
|
|
|
|
.Pp
|
|
|
|
Tracked aliases allow the shell to remember where it found a particular
|
|
|
|
command.
|
|
|
|
The first time the shell does a path search for a command that is
|
|
|
|
marked as a tracked alias, it saves the full path of the command.
|
|
|
|
The next
|
|
|
|
time the command is executed, the shell checks the saved path to see that it
|
|
|
|
is still valid, and if so, avoids repeating the path search.
|
|
|
|
Tracked aliases can be listed and created using
|
|
|
|
.Ic alias -t .
|
|
|
|
Note that changing the
|
|
|
|
.Ev PATH
|
|
|
|
parameter clears the saved paths for all tracked aliases.
|
|
|
|
If the
|
|
|
|
.Ic trackall
|
|
|
|
option is set (i.e.\&
|
|
|
|
.Ic set -o Ic trackall
|
|
|
|
or
|
|
|
|
.Ic set -h ) ,
|
|
|
|
the shell tracks all commands.
|
|
|
|
This option is set automatically for non-interactive shells.
|
|
|
|
For interactive shells, only the following commands are
|
|
|
|
automatically tracked:
|
|
|
|
.Xr cat 1 ,
|
|
|
|
.Xr cc 1 ,
|
|
|
|
.Xr chmod 1 ,
|
|
|
|
.Xr cp 1 ,
|
|
|
|
.Xr date 1 ,
|
|
|
|
.Xr ed 1 ,
|
|
|
|
.Xr emacs 1 ,
|
|
|
|
.Xr grep 1 ,
|
|
|
|
.Xr ls 1 ,
|
|
|
|
.Xr make 1 ,
|
|
|
|
.Xr mv 1 ,
|
|
|
|
.Xr pr 1 ,
|
|
|
|
.Xr rm 1 ,
|
|
|
|
.Xr sed 1 ,
|
|
|
|
.Xr sh 1 ,
|
|
|
|
.Xr vi 1 ,
|
|
|
|
and
|
|
|
|
.Xr who 1 .
|
|
|
|
.Ss Substitution
|
|
|
|
The first step the shell takes in executing a simple-command is to perform
|
|
|
|
substitutions on the words of the command.
|
|
|
|
There are three kinds of
|
|
|
|
substitution: parameter, command, and arithmetic.
|
|
|
|
Parameter substitutions,
|
|
|
|
which are described in detail in the next section, take the form
|
|
|
|
.Pf $ Ns Ar name
|
|
|
|
or
|
|
|
|
.Pf ${ Ns Ar ... Ns } ;
|
|
|
|
command substitutions take the form
|
|
|
|
.Pf $( Ns Ar command Ns \&)
|
|
|
|
or (deprecated)
|
|
|
|
.Pf ` Ns Ar command Ns ` ;
|
|
|
|
and arithmetic substitutions take the form
|
|
|
|
.Pf $(( Ns Ar expression Ns )) .
|
|
|
|
.Pp
|
|
|
|
If a substitution appears outside of double quotes, the results of the
|
|
|
|
substitution are generally subject to word or field splitting according to
|
|
|
|
the current value of the
|
|
|
|
.Ev IFS
|
|
|
|
parameter.
|
|
|
|
The
|
|
|
|
.Ev IFS
|
|
|
|
parameter specifies a list of characters which are used to break a string up
|
|
|
|
into several words; any characters from the set space, tab, and newline that
|
|
|
|
appear in the
|
|
|
|
.Ev IFS
|
|
|
|
characters are called
|
|
|
|
.Dq IFS whitespace .
|
|
|
|
Sequences of one or more
|
|
|
|
.Ev IFS
|
|
|
|
whitespace characters, in combination with zero or one
|
|
|
|
.Pf non- Ev IFS
|
|
|
|
whitespace
|
|
|
|
characters, delimit a field.
|
|
|
|
As a special case, leading and trailing
|
|
|
|
.Ev IFS
|
|
|
|
whitespace and trailing
|
|
|
|
.Ev IFS
|
|
|
|
non-whitespace are stripped (i.e. no leading or trailing empty field
|
|
|
|
is created by it); leading
|
|
|
|
.Pf non- Ev IFS
|
|
|
|
whitespace does create an empty field.
|
|
|
|
.Pp
|
|
|
|
Example: If
|
|
|
|
.Ev IFS
|
|
|
|
is set to
|
|
|
|
.Dq \*(Ltspace\*(Gt: ,
|
|
|
|
and VAR is set to
|
|
|
|
.Dq \*(Ltspace\*(GtA\*(Ltspace\*(Gt:\*(Ltspace\*(Gt\*(Ltspace\*(GtB::D ,
|
|
|
|
the substitution for $VAR results in four fields:
|
|
|
|
.Sq A ,
|
|
|
|
.Sq B ,
|
|
|
|
.Sq
|
|
|
|
(an empty field),
|
|
|
|
and
|
|
|
|
.Sq D .
|
|
|
|
Note that if the
|
|
|
|
.Ev IFS
|
|
|
|
parameter is set to the
|
|
|
|
.Dv NULL
|
|
|
|
string, no field splitting is done; if the parameter is unset, the default
|
|
|
|
value of space, tab, and newline is used.
|
|
|
|
.Pp
|
|
|
|
Also, note that the field splitting applies only to the immediate result of
|
|
|
|
the substitution.
|
|
|
|
Using the previous example, the substitution for $VAR:E
|
|
|
|
results in the fields:
|
|
|
|
.Sq A ,
|
|
|
|
.Sq B ,
|
|
|
|
.Sq ,
|
|
|
|
and
|
|
|
|
.Sq D:E ,
|
|
|
|
not
|
|
|
|
.Sq A ,
|
|
|
|
.Sq B ,
|
|
|
|
.Sq ,
|
2005-06-08 12:59:41 +02:00
|
|
|
.Sq D ,
|
2005-05-23 05:06:10 +02:00
|
|
|
and
|
|
|
|
.Sq E .
|
|
|
|
This behavior is POSIX compliant, but incompatible with some other shell
|
|
|
|
implementations which do field splitting on the word which contained the
|
|
|
|
substitution or use
|
|
|
|
.Dv IFS
|
|
|
|
as a general whitespace delimiter.
|
|
|
|
.Pp
|
|
|
|
The results of substitution are, unless otherwise specified, also subject to
|
|
|
|
brace expansion and file name expansion (see the relevant sections below).
|
|
|
|
.Pp
|
|
|
|
A command substitution is replaced by the output generated by the specified
|
2006-01-30 13:37:24 +01:00
|
|
|
command which is run in a subshell.
|
2005-05-23 05:06:10 +02:00
|
|
|
For
|
|
|
|
.Pf $( Ns Ar command Ns \&)
|
|
|
|
substitutions, normal quoting rules are used when
|
|
|
|
.Ar command
|
|
|
|
is parsed; however, for the deprecated
|
|
|
|
.Pf ` Ns Ar command Ns `
|
|
|
|
form, a
|
|
|
|
.Ql \e
|
|
|
|
followed by any of
|
|
|
|
.Ql $ ,
|
|
|
|
.Ql ` ,
|
|
|
|
or
|
|
|
|
.Ql \e
|
|
|
|
is stripped (a
|
|
|
|
.Ql \e
|
|
|
|
followed by any other character is unchanged).
|
|
|
|
As a special case in command substitutions, a command of the form
|
|
|
|
.Pf \*(Lt Ar file
|
|
|
|
is interpreted to mean substitute the contents of
|
|
|
|
.Ar file .
|
|
|
|
Note that
|
|
|
|
.Ic $(\*(Lt foo)
|
|
|
|
has the same effect as
|
|
|
|
.Ic $(cat foo) ,
|
|
|
|
but it is carried out more efficiently because no process is started.
|
|
|
|
.Pp
|
|
|
|
.Sy Note :
|
|
|
|
.Pf $( Ns Ar command Ns \&)
|
|
|
|
expressions are currently parsed by finding the matching parenthesis,
|
|
|
|
regardless of quoting.
|
|
|
|
This should be fixed soon.
|
|
|
|
.Pp
|
|
|
|
Arithmetic substitutions are replaced by the value of the specified expression.
|
|
|
|
For example, the command
|
|
|
|
.Ic print $((2+3*4))
|
|
|
|
displays 14.
|
|
|
|
See
|
|
|
|
.Sx Arithmetic expressions
|
|
|
|
for a description of an expression.
|
|
|
|
.Ss Parameters
|
|
|
|
Parameters are shell variables; they can be assigned values and their values
|
|
|
|
can be accessed using a parameter substitution.
|
|
|
|
A parameter name is either one
|
|
|
|
of the special single punctuation or digit character parameters described
|
|
|
|
below, or a letter followed by zero or more letters or digits
|
|
|
|
.Po
|
|
|
|
.Ql _
|
|
|
|
counts as a letter
|
|
|
|
.Pc .
|
|
|
|
The latter form can be treated as arrays by appending an array index of the
|
|
|
|
form
|
|
|
|
.Op Ar expr
|
|
|
|
where
|
|
|
|
.Ar expr
|
|
|
|
is an arithmetic expression.
|
|
|
|
Array indices are currently limited to the range 0 through 2147483647 (for
|
|
|
|
.Nm
|
|
|
|
only; portable maximum is 1023), inclusive.
|
|
|
|
Parameter substitutions take the form
|
|
|
|
.Pf $ Ns Ar name ,
|
|
|
|
.Pf ${ Ns Ar name Ns } ,
|
|
|
|
or
|
|
|
|
.Sm off
|
|
|
|
.Pf ${ Ar name Oo Ar expr Oc }
|
|
|
|
.Sm on
|
|
|
|
where
|
|
|
|
.Ar name
|
|
|
|
is a parameter name.
|
|
|
|
If substitution is performed on a parameter
|
|
|
|
(or an array parameter element)
|
|
|
|
that is not set, a null string is substituted unless the
|
|
|
|
.Ic nounset
|
|
|
|
option
|
|
|
|
.Po
|
|
|
|
.Ic set Fl o Ic nounset
|
|
|
|
or
|
|
|
|
.Ic set Fl u
|
|
|
|
.Pc
|
|
|
|
is set, in which case an error occurs.
|
|
|
|
.Pp
|
|
|
|
Parameters can be assigned values in a number of ways.
|
|
|
|
First, the shell implicitly sets some parameters like
|
|
|
|
.Ql # ,
|
|
|
|
.Ql PWD ,
|
|
|
|
and
|
|
|
|
.Ql $ ;
|
|
|
|
this is the only way the special single character parameters are set.
|
|
|
|
Second, parameters are imported from the shell's environment at startup.
|
|
|
|
Third, parameters can be assigned values on the command line: for example,
|
|
|
|
.Ic FOO=bar
|
|
|
|
sets the parameter
|
|
|
|
.Dq FOO
|
|
|
|
to
|
|
|
|
.Dq bar ;
|
|
|
|
multiple parameter assignments can be given on a single command line and they
|
|
|
|
can be followed by a simple-command, in which case the assignments are in
|
|
|
|
effect only for the duration of the command (such assignments are also
|
|
|
|
exported; see below for the implications of this).
|
|
|
|
Note that both the parameter name and the
|
|
|
|
.Ql =
|
|
|
|
must be unquoted for the shell to recognise a parameter assignment.
|
|
|
|
The fourth way of setting a parameter is with the
|
|
|
|
.Ic export ,
|
|
|
|
.Ic readonly ,
|
|
|
|
and
|
|
|
|
.Ic typeset
|
|
|
|
commands; see their descriptions in the
|
|
|
|
.Sx Command execution
|
|
|
|
section.
|
|
|
|
Fifth,
|
|
|
|
.Ic for
|
|
|
|
and
|
|
|
|
.Ic select
|
|
|
|
loops set parameters as well as the
|
|
|
|
.Ic getopts ,
|
|
|
|
.Ic read ,
|
|
|
|
and
|
|
|
|
.Ic set -A
|
|
|
|
commands.
|
|
|
|
Lastly, parameters can be assigned values using assignment operators
|
|
|
|
inside arithmetic expressions (see
|
|
|
|
.Sx Arithmetic expressions
|
|
|
|
below) or using the
|
|
|
|
.Sm off
|
|
|
|
.Pf ${ Ar name No = Ar value No }
|
|
|
|
.Sm on
|
|
|
|
form of the parameter substitution (see below).
|
|
|
|
.Pp
|
|
|
|
Parameters with the export attribute (set using the
|
|
|
|
.Ic export
|
|
|
|
or
|
|
|
|
.Ic typeset Fl x
|
|
|
|
commands, or by parameter assignments followed by simple commands) are put in
|
|
|
|
the environment (see
|
|
|
|
.Xr environ 7 )
|
|
|
|
of commands run by the shell as
|
|
|
|
.Ar name Ns = Ns Ar value
|
|
|
|
pairs.
|
|
|
|
The order in which parameters appear in the environment of a command is
|
|
|
|
unspecified.
|
|
|
|
When the shell starts up, it extracts parameters and their values
|
|
|
|
from its environment and automatically sets the export attribute for those
|
|
|
|
parameters.
|
|
|
|
.Pp
|
|
|
|
Modifiers can be applied to the
|
|
|
|
.Pf ${ Ns Ar name Ns }
|
|
|
|
form of parameter substitution:
|
|
|
|
.Bl -tag -width Ds
|
|
|
|
.Sm off
|
|
|
|
.It ${ Ar name No :- Ar word No }
|
|
|
|
.Sm on
|
|
|
|
If
|
|
|
|
.Ar name
|
|
|
|
is set and not
|
|
|
|
.Dv NULL ,
|
|
|
|
it is substituted; otherwise,
|
|
|
|
.Ar word
|
|
|
|
is substituted.
|
|
|
|
.Sm off
|
|
|
|
.It ${ Ar name No :+ Ar word No }
|
|
|
|
.Sm on
|
|
|
|
If
|
|
|
|
.Ar name
|
|
|
|
is set and not
|
|
|
|
.Dv NULL ,
|
|
|
|
.Ar word
|
|
|
|
is substituted; otherwise, nothing is substituted.
|
|
|
|
.Sm off
|
|
|
|
.It ${ Ar name No := Ar word No }
|
|
|
|
.Sm on
|
|
|
|
If
|
|
|
|
.Ar name
|
|
|
|
is set and not
|
|
|
|
.Dv NULL ,
|
|
|
|
it is substituted; otherwise, it is assigned
|
|
|
|
.Ar word
|
|
|
|
and the resulting value of
|
|
|
|
.Ar name
|
|
|
|
is substituted.
|
|
|
|
.Sm off
|
|
|
|
.It ${ Ar name No :? Ar word No }
|
|
|
|
.Sm on
|
|
|
|
If
|
|
|
|
.Ar name
|
|
|
|
is set and not
|
|
|
|
.Dv NULL ,
|
|
|
|
it is substituted; otherwise,
|
|
|
|
.Ar word
|
|
|
|
is printed on standard error (preceded by
|
|
|
|
.Ar name : )
|
|
|
|
and an error occurs (normally causing termination of a shell script, function,
|
|
|
|
or script sourced using the
|
|
|
|
.Sq \&.
|
|
|
|
built-in).
|
|
|
|
If
|
|
|
|
.Ar word
|
|
|
|
is omitted, the string
|
|
|
|
.Dq parameter null or not set
|
|
|
|
is used instead.
|
2005-05-26 01:31:08 +02:00
|
|
|
Currently a bug, if
|
|
|
|
.Ar word
|
|
|
|
is a variable which expands to the null string, the
|
|
|
|
error message is also printed.
|
2005-05-23 05:06:10 +02:00
|
|
|
.El
|
|
|
|
.Pp
|
|
|
|
In the above modifiers, the
|
|
|
|
.Ql \&:
|
|
|
|
can be omitted, in which case the conditions only depend on
|
|
|
|
.Ar name
|
|
|
|
being set (as opposed to set and not
|
|
|
|
.Dv NULL ) .
|
|
|
|
If
|
|
|
|
.Ar word
|
|
|
|
is needed, parameter, command, arithmetic, and tilde substitution are performed
|
|
|
|
on it; if
|
|
|
|
.Ar word
|
|
|
|
is not needed, it is not evaluated.
|
|
|
|
.Pp
|
|
|
|
The following forms of parameter substitution can also be used:
|
|
|
|
.Pp
|
|
|
|
.Bl -tag -width Ds -compact
|
|
|
|
.It Pf ${# Ns Ar name Ns \&}
|
|
|
|
The number of positional parameters if
|
|
|
|
.Ar name
|
|
|
|
is
|
|
|
|
.Ql * ,
|
|
|
|
.Ql @ ,
|
|
|
|
or not specified; otherwise the length of the string value of parameter
|
|
|
|
.Ar name .
|
|
|
|
.Pp
|
|
|
|
.It Pf ${# Ns Ar name Ns [*]}
|
|
|
|
.It Pf ${# Ns Ar name Ns [@]}
|
|
|
|
The number of elements in the array
|
|
|
|
.Ar name .
|
|
|
|
.Pp
|
|
|
|
.Sm off
|
|
|
|
.It Xo
|
|
|
|
.Pf ${ Ar name
|
|
|
|
.Pf # Ar pattern No }
|
|
|
|
.Xc
|
|
|
|
.It Xo
|
|
|
|
.Pf ${ Ar name
|
|
|
|
.Pf ## Ar pattern No }
|
|
|
|
.Xc
|
|
|
|
.Sm on
|
|
|
|
If
|
|
|
|
.Ar pattern
|
|
|
|
matches the beginning of the value of parameter
|
|
|
|
.Ar name ,
|
|
|
|
the matched text is deleted from the result of substitution.
|
|
|
|
A single
|
|
|
|
.Ql #
|
|
|
|
results in the shortest match, and two
|
|
|
|
of them result in the longest match.
|
|
|
|
.Pp
|
|
|
|
.Sm off
|
|
|
|
.It Xo
|
|
|
|
.Pf ${ Ar name
|
|
|
|
.Pf % Ar pattern No }
|
|
|
|
.Xc
|
|
|
|
.It Xo
|
|
|
|
.Pf ${ Ar name
|
|
|
|
.Pf %% Ar pattern No }
|
|
|
|
.Xc
|
|
|
|
.Sm on
|
|
|
|
Like ${..#..} substitution, but it deletes from the end of the value.
|
|
|
|
.El
|
|
|
|
.Pp
|
|
|
|
The following special parameters are implicitly set by the shell and cannot be
|
|
|
|
set directly using assignments:
|
|
|
|
.Bl -tag -width "1 ... 9"
|
|
|
|
.It Ev \&!
|
|
|
|
Process ID of the last background process started.
|
|
|
|
If no background processes have been started, the parameter is not set.
|
|
|
|
.It Ev \&#
|
|
|
|
The number of positional parameters ($1, $2, etc.).
|
|
|
|
.It Ev \&$
|
|
|
|
The PID of the shell, or the PID of the original shell if it is a subshell.
|
|
|
|
Do
|
|
|
|
.Em NOT
|
|
|
|
use this mechanism for generating temporary file names; see
|
|
|
|
.Xr mktemp 1
|
|
|
|
instead.
|
|
|
|
.It Ev -
|
|
|
|
The concatenation of the current single letter options (see the
|
|
|
|
.Ic set
|
|
|
|
command below for a list of options).
|
|
|
|
.It Ev \&?
|
|
|
|
The exit status of the last non-asynchronous command executed.
|
|
|
|
If the last command was killed by a signal,
|
|
|
|
.Ic $?\&
|
|
|
|
is set to 128 plus the signal number.
|
|
|
|
.It Ev 0
|
|
|
|
The name of the shell, determined as follows:
|
|
|
|
the first argument to
|
|
|
|
.Nm
|
|
|
|
if it was invoked with the
|
|
|
|
.Fl c
|
|
|
|
option and arguments were given; otherwise the
|
|
|
|
.Ar file
|
|
|
|
argument, if it was supplied;
|
|
|
|
or else the basename the shell was invoked with (i.e.\&
|
|
|
|
.Li argv[0] ) .
|
|
|
|
.Ev $0
|
|
|
|
is also set to the name of the current script or
|
|
|
|
the name of the current function, if it was defined with the
|
|
|
|
.Ic function
|
|
|
|
keyword (i.e. a Korn shell style function).
|
|
|
|
.It Ev 1 No ... Ev 9
|
|
|
|
The first nine positional parameters that were supplied to the shell, function,
|
|
|
|
or script sourced using the
|
|
|
|
.Sq \&.
|
|
|
|
built-in.
|
|
|
|
Further positional parameters may be accessed using
|
|
|
|
.Pf ${ Ar number Ns } .
|
|
|
|
.It Ev *
|
|
|
|
All positional parameters (except parameter 0) i.e. $1, $2, $3, ...
|
|
|
|
If used
|
|
|
|
outside of double quotes, parameters are separate words (which are subjected
|
|
|
|
to word splitting); if used within double quotes, parameters are separated
|
|
|
|
by the first character of the
|
|
|
|
.Ev IFS
|
|
|
|
parameter (or the empty string if
|
|
|
|
.Ev IFS
|
|
|
|
is
|
|
|
|
.Dv NULL ) .
|
|
|
|
.It Ev @
|
|
|
|
Same as
|
|
|
|
.Ic $* ,
|
|
|
|
unless it is used inside double quotes, in which case a separate word is
|
|
|
|
generated for each positional parameter.
|
|
|
|
If there are no positional parameters, no word is generated.
|
|
|
|
.Ic $@
|
|
|
|
can be used to access arguments, verbatim, without losing
|
|
|
|
.Dv NULL
|
|
|
|
arguments or splitting arguments with spaces.
|
|
|
|
.El
|
|
|
|
.Pp
|
|
|
|
The following parameters are set and/or used by the shell:
|
|
|
|
.Bl -tag -width "EXECSHELL"
|
|
|
|
.It Ev _ No (underscore)
|
|
|
|
When an external command is executed by the shell, this parameter is set in the
|
|
|
|
environment of the new process to the path of the executed command.
|
|
|
|
In interactive use, this parameter is also set in the parent shell to the last
|
|
|
|
word of the previous command.
|
|
|
|
.It Ev CDPATH
|
|
|
|
Search path for the
|
|
|
|
.Ic cd
|
|
|
|
built-in command.
|
|
|
|
It works the same way as
|
|
|
|
.Ev PATH
|
|
|
|
for those directories not beginning with
|
|
|
|
.Ql /
|
|
|
|
in
|
|
|
|
.Ic cd
|
|
|
|
commands.
|
|
|
|
Note that if
|
|
|
|
.Ev CDPATH
|
|
|
|
is set and does not contain
|
|
|
|
.Sq \&.
|
|
|
|
or contains an empty path, the current directory is not searched.
|
|
|
|
Also, the
|
|
|
|
.Ic cd
|
|
|
|
built-in command will display the resulting directory when a match is found
|
|
|
|
in any search path other than the empty path.
|
|
|
|
.It Ev COLUMNS
|
|
|
|
Set to the number of columns on the terminal or window.
|
|
|
|
Currently set to the
|
|
|
|
.Dq cols
|
|
|
|
value as reported by
|
|
|
|
.Xr stty 1
|
|
|
|
if that value is non-zero.
|
|
|
|
This parameter is used by the interactive line editing modes, and by the
|
|
|
|
.Ic select ,
|
|
|
|
.Ic set -o ,
|
|
|
|
and
|
|
|
|
.Ic kill -l
|
|
|
|
commands to format information columns.
|
|
|
|
.It Ev ENV
|
|
|
|
If this parameter is found to be set after any profile files are executed, the
|
|
|
|
expanded value is used as a shell startup file.
|
|
|
|
It typically contains function and alias definitions.
|
|
|
|
.It Ev ERRNO
|
|
|
|
Integer value of the shell's
|
|
|
|
.Va errno
|
|
|
|
variable.
|
|
|
|
It indicates the reason the last system call failed.
|
|
|
|
Not yet implemented.
|
|
|
|
.It Ev EXECSHELL
|
|
|
|
If set, this parameter is assumed to contain the shell that is to be used to
|
|
|
|
execute commands that
|
|
|
|
.Xr execve 2
|
|
|
|
fails to execute and which do not start with a
|
|
|
|
.Dq #! Ns Ar shell
|
|
|
|
sequence.
|
|
|
|
.It Ev FCEDIT
|
|
|
|
The editor used by the
|
|
|
|
.Ic fc
|
|
|
|
command (see below).
|
|
|
|
.It Ev FPATH
|
|
|
|
Like
|
|
|
|
.Ev PATH ,
|
|
|
|
but used when an undefined function is executed to locate the file defining the
|
|
|
|
function.
|
|
|
|
It is also searched when a command can't be found using
|
|
|
|
.Ev PATH .
|
|
|
|
See
|
|
|
|
.Sx Functions
|
|
|
|
below for more information.
|
|
|
|
.It Ev HISTFILE
|
|
|
|
The name of the file used to store command history.
|
|
|
|
When assigned to, history is loaded from the specified file.
|
|
|
|
Also, several invocations of the shell
|
|
|
|
running on the same machine will share history if their
|
|
|
|
.Ev HISTFILE
|
|
|
|
parameters all point to the same file.
|
|
|
|
.Pp
|
|
|
|
.Sy Note :
|
|
|
|
If
|
|
|
|
.Ev HISTFILE
|
|
|
|
isn't set, no history file is used.
|
|
|
|
This is different from the original Korn shell.
|
|
|
|
.It Ev HISTSIZE
|
|
|
|
The number of commands normally stored for history.
|
|
|
|
The default is 500.
|
|
|
|
.It Ev HOME
|
|
|
|
The default directory for the
|
|
|
|
.Ic cd
|
|
|
|
command and the value substituted for an unqualified
|
|
|
|
.Ic ~
|
|
|
|
(see
|
|
|
|
.Sx Tilde expansion
|
|
|
|
below).
|
|
|
|
.It Ev IFS
|
|
|
|
Internal field separator, used during substitution and by the
|
|
|
|
.Ic read
|
|
|
|
command, to split values into distinct arguments; normally set to space, tab,
|
|
|
|
and newline.
|
|
|
|
See
|
|
|
|
.Sx Substitution
|
|
|
|
above for details.
|
|
|
|
.Pp
|
|
|
|
.Sy Note :
|
|
|
|
This parameter is not imported from the environment when the shell is
|
|
|
|
started.
|
|
|
|
.It Ev KSH_VERSION
|
|
|
|
The name and version of the shell (read-only).
|
2006-08-01 14:44:17 +02:00
|
|
|
See also the version commands in
|
|
|
|
.Sx Emacs editing mode
|
|
|
|
and
|
|
|
|
.Sx Vi editing mode
|
|
|
|
sections, below.
|
2005-05-23 05:06:10 +02:00
|
|
|
.It Ev LINENO
|
|
|
|
The line number of the function or shell script that is currently being
|
|
|
|
executed.
|
|
|
|
.It Ev LINES
|
|
|
|
Set to the number of lines on the terminal or window.
|
|
|
|
.It Ev OLDPWD
|
|
|
|
The previous working directory.
|
|
|
|
Unset if
|
|
|
|
.Ic cd
|
|
|
|
has not successfully changed directories since the shell started, or if the
|
|
|
|
shell doesn't know where it is.
|
|
|
|
.It Ev OPTARG
|
|
|
|
When using
|
|
|
|
.Ic getopts ,
|
|
|
|
it contains the argument for a parsed option, if it requires one.
|
|
|
|
.It Ev OPTIND
|
2006-08-01 16:09:20 +02:00
|
|
|
The index of the next argument to be processed when using
|
2005-05-23 05:06:10 +02:00
|
|
|
.Ic getopts .
|
|
|
|
Assigning 1 to this parameter causes
|
|
|
|
.Ic getopts
|
|
|
|
to process arguments from the beginning the next time it is invoked.
|
|
|
|
.It Ev PATH
|
|
|
|
A colon separated list of directories that are searched when looking for
|
|
|
|
commands and files sourced using the
|
|
|
|
.Sq \&.
|
|
|
|
command (see below).
|
|
|
|
An empty string resulting from a leading or trailing
|
|
|
|
colon, or two adjacent colons, is treated as a
|
|
|
|
.Sq \&.
|
|
|
|
(the current directory).
|
|
|
|
.It Ev PPID
|
|
|
|
The process ID of the shell's parent (read-only).
|
|
|
|
.It Ev PS1
|
|
|
|
The primary prompt for interactive shells.
|
|
|
|
Parameter, command, and arithmetic
|
|
|
|
substitutions are performed, and
|
|
|
|
.Ql \&!
|
|
|
|
is replaced with the current command number (see the
|
|
|
|
.Ic fc
|
|
|
|
command below).
|
|
|
|
A literal
|
|
|
|
.Ql \&!
|
|
|
|
can be put in the prompt by placing
|
|
|
|
.Ql !!
|
|
|
|
in
|
|
|
|
.Ev PS1 .
|
2006-08-02 15:34:03 +02:00
|
|
|
.Pp
|
2006-08-02 13:50:30 +02:00
|
|
|
The default prompt is
|
|
|
|
.Sq $\ \&
|
|
|
|
for non-root users,
|
|
|
|
.Sq #\ \&
|
|
|
|
for root.
|
|
|
|
If
|
|
|
|
.Nm
|
|
|
|
is invoked by root and
|
|
|
|
.Ev PS1
|
|
|
|
does not contain a
|
|
|
|
.Sq #
|
|
|
|
character, the default value will be used even if
|
|
|
|
.Ev PS1
|
|
|
|
already exists in the environment.
|
2005-05-23 05:06:10 +02:00
|
|
|
.Pp
|
2006-08-02 13:50:30 +02:00
|
|
|
The
|
|
|
|
.Nm
|
|
|
|
distribution comes with a sample
|
|
|
|
.Pa dot.mkshrc
|
|
|
|
containing a sophisticated example, but you might like the following one
|
|
|
|
(note that ${HOSTNAME:=$(hostname -s)} and the
|
2006-05-08 14:12:36 +02:00
|
|
|
root-vs-user distinguishing clause are (in this example) executed at
|
|
|
|
.Ev PS1
|
|
|
|
assignment time, while the $USER and $PWD are escaped
|
|
|
|
and thus will be evaluated each time a prompt is displayed):
|
2006-08-02 13:50:30 +02:00
|
|
|
.Bd -literal
|
|
|
|
PS1='${USER:=$(id -un)}'"@${HOSTNAME:=$(hostname -s)}:\e$PWD $(
|
|
|
|
if (( $(id -u) )); then print \e$; else print \e#; fi) "
|
2006-05-08 14:12:36 +02:00
|
|
|
.Ed
|
|
|
|
.Pp
|
2005-05-23 05:06:10 +02:00
|
|
|
Note that since the command-line editors try to figure out how long the prompt
|
|
|
|
is (so they know how far it is to the edge of the screen), escape codes in
|
|
|
|
the prompt tend to mess things up.
|
|
|
|
You can tell the shell not to count certain
|
2006-08-02 12:41:03 +02:00
|
|
|
sequences (such as escape codes) by prefixing your prompt with a
|
2005-05-23 05:06:10 +02:00
|
|
|
character (such as control-A) followed by a carriage return and then delimiting
|
2006-08-02 12:41:03 +02:00
|
|
|
the escape codes with this character.
|
|
|
|
Any occurences of that character in the prompt are not printed.
|
2005-05-23 05:06:10 +02:00
|
|
|
By the way, don't blame me for
|
2006-08-02 12:41:03 +02:00
|
|
|
this hack; it's derived from the original
|
|
|
|
.Xr ksh88 1 ,
|
|
|
|
which did print the delimiter character so you were out of luck
|
|
|
|
if you did not have any non-printing characters.
|
2005-05-23 05:06:10 +02:00
|
|
|
.Pp
|
|
|
|
Since Backslashes and other special characters may be
|
|
|
|
interpreted by the shell, to set
|
|
|
|
.Ev PS1
|
|
|
|
either escape the backslash itself,
|
|
|
|
or use double quotes.
|
|
|
|
The latter is more practical.
|
|
|
|
This is a more complex example,
|
|
|
|
avoiding to directly enter special characters (for example with
|
2006-08-02 13:50:30 +02:00
|
|
|
.Ic ^V
|
2005-05-23 05:06:10 +02:00
|
|
|
in the emacs editing mode),
|
|
|
|
which embeds the current working directory,
|
|
|
|
in reverse video,
|
|
|
|
in the prompt string:
|
|
|
|
.Bd -literal -offset indent
|
|
|
|
x=$(print \e\e001)
|
2006-08-02 13:50:30 +02:00
|
|
|
PS1="$x$(print \e\er)$x$(tput smso)$x\e$PWD$x$(tput rmso)$x\*(Gt "
|
2005-05-23 05:06:10 +02:00
|
|
|
.Ed
|
|
|
|
.It Ev PS2
|
|
|
|
Secondary prompt string, by default
|
|
|
|
.Sq \*(Gt\ \& ,
|
|
|
|
used when more input is needed to complete a command.
|
|
|
|
.It Ev PS3
|
|
|
|
Prompt used by the
|
|
|
|
.Ic select
|
|
|
|
statement when reading a menu selection.
|
|
|
|
The default is
|
|
|
|
.Sq #?\ \& .
|
|
|
|
.It Ev PS4
|
|
|
|
Used to prefix commands that are printed during execution tracing (see the
|
|
|
|
.Ic set Fl x
|
|
|
|
command below).
|
|
|
|
Parameter, command, and arithmetic substitutions are performed
|
|
|
|
before it is printed.
|
|
|
|
The default is
|
|
|
|
.Sq +\ \& .
|
|
|
|
.It Ev PWD
|
|
|
|
The current working directory.
|
|
|
|
May be unset or
|
|
|
|
.Dv NULL
|
|
|
|
if the shell doesn't know where it is.
|
|
|
|
.It Ev RANDOM
|
|
|
|
Every time
|
|
|
|
.Ev RANDOM
|
2006-09-13 18:14:29 +02:00
|
|
|
is referenced, it is assigned a pseudo-random number first.
|
|
|
|
By default, if available,
|
2005-05-23 05:06:10 +02:00
|
|
|
.Xr arc4random 3
|
2006-09-13 18:14:29 +02:00
|
|
|
is used to produce unsigned 31\-bit values (0\-2147483647)
|
|
|
|
whose quality depends on the operating environment.
|
|
|
|
If
|
2005-05-23 05:06:10 +02:00
|
|
|
.Ev RANDOM
|
2006-09-13 18:14:29 +02:00
|
|
|
is assigned a value, it is used as the seed to
|
2005-05-23 05:06:10 +02:00
|
|
|
.Xr srand 3
|
2006-09-13 18:14:29 +02:00
|
|
|
and subsequent references yield a semi-predictable sequence
|
|
|
|
of unsigned 15\-bit results (0\-32767) employing
|
|
|
|
.Xr rand 3 .
|
2005-05-23 05:06:10 +02:00
|
|
|
.It Ev REPLY
|
|
|
|
Default parameter for the
|
|
|
|
.Ic read
|
|
|
|
command if no names are given.
|
|
|
|
Also used in
|
|
|
|
.Ic select
|
|
|
|
loops to store the value that is read from standard input.
|
|
|
|
.It Ev SECONDS
|
|
|
|
The number of seconds since the shell started or, if the parameter has been
|
|
|
|
assigned an integer value, the number of seconds since the assignment plus the
|
|
|
|
value that was assigned.
|
|
|
|
.It Ev TMOUT
|
|
|
|
If set to a positive integer in an interactive shell, it specifies the maximum
|
|
|
|
number of seconds the shell will wait for input after printing the primary
|
|
|
|
prompt
|
|
|
|
.Pq Ev PS1 .
|
|
|
|
If the time is exceeded, the shell exits.
|
|
|
|
.It Ev TMPDIR
|
|
|
|
The directory temporary shell files are created in.
|
|
|
|
If this parameter is not
|
|
|
|
set, or does not contain the absolute path of a writable directory, temporary
|
|
|
|
files are created in
|
|
|
|
.Pa /tmp .
|
|
|
|
.El
|
|
|
|
.Ss Tilde expansion
|
2006-01-30 13:37:24 +01:00
|
|
|
Tilde expansion which is done in parallel with parameter substitution, is done
|
2005-05-23 05:06:10 +02:00
|
|
|
on words starting with an unquoted
|
|
|
|
.Ql ~ .
|
|
|
|
The characters following the tilde, up to the first
|
|
|
|
.Ql / ,
|
|
|
|
if any, are assumed to be a login name.
|
|
|
|
If the login name is empty,
|
|
|
|
.Ql + ,
|
|
|
|
or
|
|
|
|
.Ql - ,
|
|
|
|
the value of the
|
|
|
|
.Ev HOME ,
|
|
|
|
.Ev PWD ,
|
|
|
|
or
|
|
|
|
.Ev OLDPWD
|
|
|
|
parameter is substituted, respectively.
|
|
|
|
Otherwise, the password file is
|
|
|
|
searched for the login name, and the tilde expression is substituted with the
|
|
|
|
user's home directory.
|
|
|
|
If the login name is not found in the password file or
|
|
|
|
if any quoting or parameter substitution occurs in the login name, no
|
|
|
|
substitution is performed.
|
|
|
|
.Pp
|
|
|
|
In parameter assignments
|
|
|
|
(such as those preceding a simple-command or those occurring
|
|
|
|
in the arguments of
|
|
|
|
.Ic alias ,
|
|
|
|
.Ic export ,
|
|
|
|
.Ic readonly ,
|
|
|
|
and
|
|
|
|
.Ic typeset ) ,
|
|
|
|
tilde expansion is done after any assignment
|
|
|
|
(i.e. after the equals sign)
|
|
|
|
or after an unquoted colon
|
|
|
|
.Pq Sq \&: ;
|
|
|
|
login names are also delimited by colons.
|
|
|
|
.Pp
|
|
|
|
The home directory of previously expanded login names are cached and re-used.
|
|
|
|
The
|
|
|
|
.Ic alias -d
|
|
|
|
command may be used to list, change, and add to this cache (e.g.\&
|
|
|
|
.Ic alias -d fac=/usr/local/facilities; cd ~fac/bin ) .
|
|
|
|
.Ss Brace expansion (alteration)
|
|
|
|
Brace expressions take the following form:
|
|
|
|
.Bd -unfilled -offset indent
|
|
|
|
.Sm off
|
|
|
|
.Xo
|
|
|
|
.Ar prefix No { Ar str1 No ,...,
|
|
|
|
.Ar strN No } Ar suffix
|
|
|
|
.Xc
|
|
|
|
.Sm on
|
|
|
|
.Ed
|
|
|
|
.Pp
|
|
|
|
The expressions are expanded to
|
|
|
|
.Ar N
|
|
|
|
words, each of which is the concatenation of
|
|
|
|
.Ar prefix ,
|
|
|
|
.Ar str Ns i ,
|
|
|
|
and
|
|
|
|
.Ar suffix
|
|
|
|
(e.g.\&
|
|
|
|
.Dq a{c,b{X,Y},d}e
|
|
|
|
expands to four words:
|
|
|
|
.Dq ace ,
|
|
|
|
.Dq abXe ,
|
|
|
|
.Dq abYe ,
|
|
|
|
and
|
|
|
|
.Dq ade ) .
|
|
|
|
As noted in the example, brace expressions can be nested and the resulting
|
|
|
|
words are not sorted.
|
|
|
|
Brace expressions must contain an unquoted comma
|
|
|
|
.Pq Sq \&,
|
|
|
|
for expansion to occur (e.g.\&
|
|
|
|
.Ic {}
|
|
|
|
and
|
|
|
|
.Ic {foo}
|
|
|
|
are not expanded).
|
|
|
|
Brace expansion is carried out after parameter substitution
|
|
|
|
and before file name generation.
|
|
|
|
.Ss File name patterns
|
|
|
|
A file name pattern is a word containing one or more unquoted
|
|
|
|
.Ql \&? ,
|
|
|
|
.Ql * ,
|
|
|
|
.Ql + ,
|
|
|
|
.Ql @ ,
|
|
|
|
or
|
|
|
|
.Ql \&!
|
|
|
|
characters or
|
|
|
|
.Dq [..]
|
|
|
|
sequences.
|
|
|
|
Once brace expansion has been performed, the shell replaces file
|
|
|
|
name patterns with the sorted names of all the files that match the pattern
|
|
|
|
(if no files match, the word is left unchanged).
|
|
|
|
The pattern elements have the following meaning:
|
|
|
|
.Bl -tag -width Ds
|
|
|
|
.It \&?
|
|
|
|
Matches any single character.
|
|
|
|
.It \&*
|
|
|
|
Matches any sequence of characters.
|
|
|
|
.It [..]
|
|
|
|
Matches any of the characters inside the brackets.
|
|
|
|
Ranges of characters can be
|
|
|
|
specified by separating two characters by a
|
|
|
|
.Ql -
|
|
|
|
(e.g.\&
|
|
|
|
.Dq [a0-9]
|
|
|
|
matches the letter
|
|
|
|
.Sq a
|
|
|
|
or any digit).
|
|
|
|
In order to represent itself, a
|
|
|
|
.Ql -
|
|
|
|
must either be quoted or the first or last character in the character list.
|
|
|
|
Similarly, a
|
|
|
|
.Ql \&]
|
|
|
|
must be quoted or the first character in the list if it is to represent itself
|
|
|
|
instead of the end of the list.
|
|
|
|
Also, a
|
|
|
|
.Ql \&!
|
|
|
|
appearing at the start of the list has special meaning (see below), so to
|
|
|
|
represent itself it must be quoted or appear later in the list.
|
|
|
|
.It [!..]
|
|
|
|
Like [..],
|
|
|
|
except it matches any character not inside the brackets.
|
|
|
|
.Sm off
|
|
|
|
.It *( Ar pattern\*(Ba No ...\*(Ba Ar pattern )
|
|
|
|
.Sm on
|
|
|
|
Matches any string of characters that matches zero or more occurrences of the
|
|
|
|
specified patterns.
|
|
|
|
Example: The pattern
|
2006-01-27 11:58:36 +01:00
|
|
|
.Ic *(foo\*(Babar)
|
2005-05-23 05:06:10 +02:00
|
|
|
matches the strings
|
|
|
|
.Dq ,
|
|
|
|
.Dq foo ,
|
|
|
|
.Dq bar ,
|
|
|
|
.Dq foobarfoo ,
|
|
|
|
etc.
|
|
|
|
.Sm off
|
|
|
|
.It +( Ar pattern\*(Ba No ...\*(Ba Ar pattern )
|
|
|
|
.Sm on
|
|
|
|
Matches any string of characters that matches one or more occurrences of the
|
|
|
|
specified patterns.
|
|
|
|
Example: The pattern
|
2006-01-27 11:58:36 +01:00
|
|
|
.Ic +(foo\*(Babar)
|
2005-05-23 05:06:10 +02:00
|
|
|
matches the strings
|
|
|
|
.Dq foo ,
|
|
|
|
.Dq bar ,
|
|
|
|
.Dq foobar ,
|
|
|
|
etc.
|
|
|
|
.Sm off
|
|
|
|
.It ?( Ar pattern\*(Ba No ...\*(Ba Ar pattern )
|
|
|
|
.Sm on
|
|
|
|
Matches the empty string or a string that matches one of the specified
|
|
|
|
patterns.
|
|
|
|
Example: The pattern
|
2006-01-27 11:58:36 +01:00
|
|
|
.Ic ?(foo\*(Babar)
|
2005-05-23 05:06:10 +02:00
|
|
|
only matches the strings
|
|
|
|
.Dq ,
|
|
|
|
.Dq foo ,
|
|
|
|
and
|
|
|
|
.Dq bar .
|
|
|
|
.Sm off
|
|
|
|
.It @( Ar pattern\*(Ba No ...\*(Ba Ar pattern )
|
|
|
|
.Sm on
|
|
|
|
Matches a string that matches one of the specified patterns.
|
|
|
|
Example: The pattern
|
2006-01-27 11:58:36 +01:00
|
|
|
.Ic @(foo\*(Babar)
|
2005-05-23 05:06:10 +02:00
|
|
|
only matches the strings
|
|
|
|
.Dq foo
|
|
|
|
and
|
|
|
|
.Dq bar .
|
|
|
|
.Sm off
|
|
|
|
.It !( Ar pattern\*(Ba No ...\*(Ba Ar pattern )
|
|
|
|
.Sm on
|
|
|
|
Matches any string that does not match one of the specified patterns.
|
|
|
|
Examples: The pattern
|
2006-01-27 11:58:36 +01:00
|
|
|
.Ic !(foo\*(Babar)
|
2005-05-23 05:06:10 +02:00
|
|
|
matches all strings except
|
|
|
|
.Dq foo
|
|
|
|
and
|
|
|
|
.Dq bar ;
|
|
|
|
the pattern
|
|
|
|
.Ic !(*)
|
|
|
|
matches no strings; the pattern
|
|
|
|
.Ic !(?)*\&
|
|
|
|
matches all strings (think about it).
|
|
|
|
.El
|
|
|
|
.Pp
|
|
|
|
Note that
|
|
|
|
.Nm mksh
|
2006-08-28 05:31:01 +02:00
|
|
|
.Po and Nm pdksh Pc
|
2005-05-23 05:06:10 +02:00
|
|
|
never matches
|
|
|
|
.Sq \&.
|
|
|
|
and
|
|
|
|
.Sq .. ,
|
2006-08-28 05:31:01 +02:00
|
|
|
but
|
|
|
|
.At
|
2005-05-23 05:06:10 +02:00
|
|
|
.Nm ksh ,
|
|
|
|
Bourne
|
|
|
|
.Nm sh ,
|
|
|
|
and GNU
|
|
|
|
.Nm bash
|
|
|
|
do.
|
|
|
|
.Pp
|
|
|
|
Note that none of the above pattern elements match either a period
|
|
|
|
.Pq Sq \&.
|
|
|
|
at the start of a file name or a slash
|
|
|
|
.Pq Sq / ,
|
|
|
|
even if they are explicitly used in a [..] sequence; also, the names
|
|
|
|
.Sq \&.
|
|
|
|
and
|
|
|
|
.Sq ..
|
|
|
|
are never matched, even by the pattern
|
|
|
|
.Sq .* .
|
|
|
|
.Pp
|
|
|
|
If the
|
|
|
|
.Ic markdirs
|
|
|
|
option is set, any directories that result from file name generation are marked
|
|
|
|
with a trailing
|
|
|
|
.Ql / .
|
|
|
|
.Pp
|
|
|
|
The POSIX character classes (i.e.\&
|
|
|
|
.Pf [: Ns Ar class-name Ns :]
|
|
|
|
inside a [..] expression) are not yet implemented.
|
|
|
|
.Ss Input/output redirection
|
|
|
|
When a command is executed, its standard input, standard output, and standard
|
|
|
|
error (file descriptors 0, 1, and 2, respectively) are normally inherited from
|
|
|
|
the shell.
|
|
|
|
Three exceptions to this are commands in pipelines, for which
|
|
|
|
standard input and/or standard output are those set up by the pipeline,
|
|
|
|
asynchronous commands created when job control is disabled, for which standard
|
|
|
|
input is initially set to be from
|
|
|
|
.Pa /dev/null ,
|
|
|
|
and commands for which any of the following redirections have been specified:
|
|
|
|
.Bl -tag -width Ds
|
|
|
|
.It \*(Gt Ar file
|
|
|
|
Standard output is redirected to
|
|
|
|
.Ar file .
|
|
|
|
If
|
|
|
|
.Ar file
|
|
|
|
does not exist, it is created; if it does exist, is a regular file, and the
|
|
|
|
.Ic noclobber
|
|
|
|
option is set, an error occurs; otherwise, the file is truncated.
|
|
|
|
Note that this means the command
|
|
|
|
.Ic cmd \*(Lt foo \*(Gt foo
|
|
|
|
will open
|
|
|
|
.Ar foo
|
|
|
|
for reading and then truncate it when it opens it for writing, before
|
|
|
|
.Ar cmd
|
|
|
|
gets a chance to actually read
|
|
|
|
.Ar foo .
|
|
|
|
.It \*(Gt\*(Ba Ar file
|
|
|
|
Same as
|
|
|
|
.Ic \*(Gt ,
|
|
|
|
except the file is truncated, even if the
|
|
|
|
.Ic noclobber
|
|
|
|
option is set.
|
|
|
|
.It \*(Gt\*(Gt Ar file
|
|
|
|
Same as
|
|
|
|
.Ic \*(Gt ,
|
|
|
|
except if
|
|
|
|
.Ar file
|
|
|
|
exists it is appended to instead of being truncated.
|
|
|
|
Also, the file is opened
|
|
|
|
in append mode, so writes always go to the end of the file (see
|
|
|
|
.Xr open 2 ) .
|
|
|
|
.It \*(Lt Ar file
|
|
|
|
Standard input is redirected from
|
|
|
|
.Ar file ,
|
|
|
|
which is opened for reading.
|
|
|
|
.It \*(Lt\*(Gt Ar file
|
|
|
|
Same as
|
|
|
|
.Ic \*(Lt ,
|
|
|
|
except the file is opened for reading and writing.
|
|
|
|
.It \*(Lt\*(Lt Ar marker
|
|
|
|
After reading the command line containing this kind of redirection (called a
|
|
|
|
.Dq here document ) ,
|
|
|
|
the shell copies lines from the command source into a temporary file until a
|
|
|
|
line matching
|
|
|
|
.Ar marker
|
|
|
|
is read.
|
|
|
|
When the command is executed, standard input is redirected from the
|
|
|
|
temporary file.
|
|
|
|
If
|
|
|
|
.Ar marker
|
|
|
|
contains no quoted characters, the contents of the temporary file are processed
|
|
|
|
as if enclosed in double quotes each time the command is executed, so
|
|
|
|
parameter, command, and arithmetic substitutions are performed, along with
|
|
|
|
backslash
|
|
|
|
.Pq Sq \e
|
|
|
|
escapes for
|
|
|
|
.Ql $ ,
|
|
|
|
.Ql ` ,
|
|
|
|
.Ql \e ,
|
|
|
|
and
|
2006-02-16 12:48:32 +01:00
|
|
|
.Ql \enewline ,
|
|
|
|
but not for
|
|
|
|
.Ql \&" .
|
2005-05-23 05:06:10 +02:00
|
|
|
If multiple here documents are used on the same command line, they are saved in
|
|
|
|
order.
|
|
|
|
.It \*(Lt\*(Lt- Ar marker
|
|
|
|
Same as
|
|
|
|
.Ic \*(Lt\*(Lt ,
|
|
|
|
except leading tabs are stripped from lines in the here document.
|
|
|
|
.It \*(Lt& Ar fd
|
|
|
|
Standard input is duplicated from file descriptor
|
|
|
|
.Ar fd .
|
|
|
|
.Ar fd
|
|
|
|
can be a single digit, indicating the number of an existing file descriptor;
|
|
|
|
the letter
|
|
|
|
.Ql p ,
|
|
|
|
indicating the file descriptor associated with the output of the current
|
|
|
|
co-process; or the character
|
|
|
|
.Ql - ,
|
|
|
|
indicating standard input is to be closed.
|
|
|
|
.It \*(Gt& Ar fd
|
|
|
|
Same as
|
|
|
|
.Ic \*(Lt& ,
|
|
|
|
except the operation is done on standard output.
|
|
|
|
.El
|
|
|
|
.Pp
|
|
|
|
In any of the above redirections, the file descriptor that is redirected
|
|
|
|
(i.e. standard input or standard output)
|
|
|
|
can be explicitly given by preceding the
|
|
|
|
redirection with a single digit.
|
|
|
|
Parameter, command, and arithmetic
|
|
|
|
substitutions, tilde substitutions, and (if the shell is interactive)
|
|
|
|
file name generation are all performed on the
|
|
|
|
.Ar file ,
|
|
|
|
.Ar marker ,
|
|
|
|
and
|
|
|
|
.Ar fd
|
|
|
|
arguments of redirections.
|
|
|
|
Note, however, that the results of any file name
|
|
|
|
generation are only used if a single file is matched; if multiple files match,
|
|
|
|
the word with the expanded file name generation characters is used.
|
|
|
|
Note
|
|
|
|
that in restricted shells, redirections which can create files cannot be used.
|
|
|
|
.Pp
|
|
|
|
For simple-commands, redirections may appear anywhere in the command; for
|
|
|
|
compound-commands
|
|
|
|
.Po
|
|
|
|
.Ic if
|
|
|
|
statements, etc.
|
|
|
|
.Pc ,
|
|
|
|
any redirections must appear at the end.
|
|
|
|
Redirections are processed after
|
|
|
|
pipelines are created and in the order they are given, so the following
|
|
|
|
will print an error with a line number prepended to it:
|
|
|
|
.Pp
|
|
|
|
.D1 $ cat /foo/bar 2\*(Gt&1 \*(Gt /dev/null \*(Ba cat -n
|
|
|
|
.Ss Arithmetic expressions
|
|
|
|
Integer arithmetic expressions can be used with the
|
|
|
|
.Ic let
|
|
|
|
command, inside $((..)) expressions, inside array references (e.g.\&
|
|
|
|
.Ar name Ns Bq Ar expr ) ,
|
|
|
|
as numeric arguments to the
|
|
|
|
.Ic test
|
|
|
|
command, and as the value of an assignment to an integer parameter.
|
|
|
|
.Pp
|
|
|
|
Expressions may contain alpha-numeric parameter identifiers, array references,
|
|
|
|
and integer constants and may be combined with the following C operators
|
|
|
|
(listed and grouped in increasing order of precedence):
|
|
|
|
.Pp
|
|
|
|
Unary operators:
|
|
|
|
.Bd -literal -offset indent
|
|
|
|
+ - ! ~ ++ --
|
|
|
|
.Ed
|
|
|
|
.Pp
|
|
|
|
Binary operators:
|
|
|
|
.Bd -literal -offset indent
|
|
|
|
,
|
|
|
|
= *= /= %= += -= \*(Lt\*(Lt= \*(Gt\*(Gt= &= ^= \*(Ba=
|
|
|
|
\*(Ba\*(Ba
|
|
|
|
&&
|
|
|
|
\*(Ba
|
|
|
|
^
|
|
|
|
&
|
|
|
|
== !=
|
|
|
|
\*(Lt \*(Lt= \*(Gt= \*(Gt
|
|
|
|
\*(Lt\*(Lt \*(Gt\*(Gt
|
|
|
|
+ -
|
|
|
|
* / %
|
|
|
|
.Ed
|
|
|
|
.Pp
|
|
|
|
Ternary operators:
|
|
|
|
.Bd -literal -offset indent
|
|
|
|
?: (precedence is immediately higher than assignment)
|
|
|
|
.Ed
|
|
|
|
.Pp
|
|
|
|
Grouping operators:
|
|
|
|
.Bd -literal -offset indent
|
|
|
|
( )
|
|
|
|
.Ed
|
|
|
|
.Pp
|
|
|
|
Integer constants may be specified with arbitrary bases using the notation
|
|
|
|
.Ar base Ns # Ns Ar number ,
|
|
|
|
where
|
|
|
|
.Ar base
|
|
|
|
is a decimal integer specifying the base, and
|
|
|
|
.Ar number
|
|
|
|
is a number in the specified base.
|
|
|
|
Additionally,
|
|
|
|
integers may be prefixed with
|
|
|
|
.Sq 0X
|
|
|
|
or
|
|
|
|
.Sq 0x
|
2006-08-28 05:31:01 +02:00
|
|
|
(specifying base 16), similar to
|
|
|
|
.At
|
2005-05-26 01:31:08 +02:00
|
|
|
.Nm ksh ,
|
2005-05-23 05:06:10 +02:00
|
|
|
or
|
|
|
|
.Sq 0
|
2005-05-26 01:31:08 +02:00
|
|
|
(base 8), as an
|
|
|
|
.Nm
|
|
|
|
extension, in all forms of arithmetic expressions,
|
2005-05-23 05:06:10 +02:00
|
|
|
except as numeric arguments to the
|
|
|
|
.Ic test
|
|
|
|
command.
|
|
|
|
.Pp
|
|
|
|
The operators are evaluated as follows:
|
|
|
|
.Bl -tag -width Ds -offset indent
|
|
|
|
.It unary +
|
|
|
|
Result is the argument (included for completeness).
|
|
|
|
.It unary -
|
|
|
|
Negation.
|
|
|
|
.It \&!
|
|
|
|
Logical NOT;
|
|
|
|
the result is 1 if argument is zero, 0 if not.
|
|
|
|
.It ~
|
|
|
|
Arithmetic (bit-wise) NOT.
|
|
|
|
.It ++
|
|
|
|
Increment; must be applied to a parameter (not a literal or other expression).
|
|
|
|
The parameter is incremented by 1.
|
|
|
|
When used as a prefix operator, the result
|
|
|
|
is the incremented value of the parameter; when used as a postfix operator, the
|
|
|
|
result is the original value of the parameter.
|
|
|
|
.It --
|
|
|
|
Similar to
|
|
|
|
.Ic ++ ,
|
|
|
|
except the parameter is decremented by 1.
|
|
|
|
.It \&,
|
|
|
|
Separates two arithmetic expressions; the left-hand side is evaluated first,
|
|
|
|
then the right.
|
|
|
|
The result is the value of the expression on the right-hand side.
|
|
|
|
.It =
|
|
|
|
Assignment; the variable on the left is set to the value on the right.
|
|
|
|
.It Xo
|
|
|
|
.No *= /= += -= \*(Lt\*(Lt=
|
|
|
|
.No \*(Gt\*(Gt= &= ^= \*(Ba=
|
|
|
|
.Xc
|
|
|
|
Assignment operators.
|
|
|
|
.Sm off
|
|
|
|
.Aq Xo Ar var
|
|
|
|
.Aq Ar op
|
|
|
|
.No = Aq Ar expr
|
|
|
|
.Xc
|
|
|
|
.Sm on
|
|
|
|
is the same as
|
|
|
|
.Sm off
|
|
|
|
.Aq Xo Ar var
|
|
|
|
.No = Aq Ar var
|
|
|
|
.Aq Ar op
|
|
|
|
.Aq Ar expr ,
|
|
|
|
.Xc
|
|
|
|
.Sm on
|
|
|
|
with any operator precedence in
|
|
|
|
.Aq Ar expr
|
|
|
|
preserved.
|
|
|
|
For example,
|
|
|
|
.Dq var1 *= 5 + 3
|
|
|
|
is the same as specifying
|
|
|
|
.Dq var1 = var1 * (5 + 3) .
|
|
|
|
.It \*(Ba\*(Ba
|
|
|
|
Logical OR;
|
|
|
|
the result is 1 if either argument is non-zero, 0 if not.
|
|
|
|
The right argument is evaluated only if the left argument is zero.
|
|
|
|
.It &&
|
|
|
|
Logical AND;
|
|
|
|
the result is 1 if both arguments are non-zero, 0 if not.
|
|
|
|
The right argument is evaluated only if the left argument is non-zero.
|
|
|
|
.It \*(Ba
|
|
|
|
Arithmetic (bit-wise) OR.
|
|
|
|
.It ^
|
|
|
|
Arithmetic (bit-wise) XOR
|
|
|
|
(exclusive-OR).
|
|
|
|
.It &
|
|
|
|
Arithmetic (bit-wise) AND.
|
|
|
|
.It ==
|
|
|
|
Equal; the result is 1 if both arguments are equal, 0 if not.
|
|
|
|
.It !=
|
|
|
|
Not equal; the result is 0 if both arguments are equal, 1 if not.
|
|
|
|
.It \*(Lt
|
|
|
|
Less than; the result is 1 if the left argument is less than the right, 0 if
|
|
|
|
not.
|
|
|
|
.It \*(Lt= \*(Gt= \*(Gt
|
|
|
|
Less than or equal, greater than or equal, greater than.
|
|
|
|
See
|
|
|
|
.Ic \*(Lt .
|
|
|
|
.It \*(Lt\*(Lt \*(Gt\*(Gt
|
|
|
|
Shift left (right); the result is the left argument with its bits shifted left
|
|
|
|
(right) by the amount given in the right argument.
|
|
|
|
.It + - * /
|
|
|
|
Addition, subtraction, multiplication, and division.
|
|
|
|
.It %
|
|
|
|
Remainder; the result is the remainder of the division of the left argument by
|
|
|
|
the right.
|
|
|
|
The sign of the result is unspecified if either argument is negative.
|
|
|
|
.It Xo
|
|
|
|
.Sm off
|
|
|
|
.Aq Ar arg1 ?
|
|
|
|
.Aq Ar arg2 :
|
|
|
|
.Aq Ar arg3
|
|
|
|
.Sm on
|
|
|
|
.Xc
|
|
|
|
If
|
|
|
|
.Aq Ar arg1
|
|
|
|
is non-zero, the result is
|
|
|
|
.Aq Ar arg2 ;
|
|
|
|
otherwise the result is
|
|
|
|
.Aq Ar arg3 .
|
|
|
|
.El
|
|
|
|
.Ss Co-processes
|
2006-01-30 13:37:24 +01:00
|
|
|
A co-process (which is a pipeline created with the
|
2005-05-23 05:06:10 +02:00
|
|
|
.Sq \*(Ba&
|
2006-01-30 13:37:24 +01:00
|
|
|
operator) is an asynchronous process that the shell can both write to (using
|
2005-05-23 05:06:10 +02:00
|
|
|
.Ic print -p )
|
|
|
|
and read from (using
|
|
|
|
.Ic read -p ) .
|
|
|
|
The input and output of the co-process can also be manipulated using
|
|
|
|
.Ic \*(Gt&p
|
|
|
|
and
|
|
|
|
.Ic \*(Lt&p
|
|
|
|
redirections, respectively.
|
|
|
|
Once a co-process has been started, another can't
|
|
|
|
be started until the co-process exits, or until the co-process's input has been
|
|
|
|
redirected using an
|
|
|
|
.Ic exec Ar n Ns Ic \*(Gt&p
|
|
|
|
redirection.
|
|
|
|
If a co-process's input is redirected in this way, the next
|
|
|
|
co-process to be started will share the output with the first co-process,
|
|
|
|
unless the output of the initial co-process has been redirected using an
|
|
|
|
.Ic exec Ar n Ns Ic \*(Lt&p
|
|
|
|
redirection.
|
|
|
|
.Pp
|
|
|
|
Some notes concerning co-processes:
|
|
|
|
.Bl -bullet
|
|
|
|
.It
|
|
|
|
The only way to close the co-process's input (so the co-process reads an
|
|
|
|
end-of-file) is to redirect the input to a numbered file descriptor and then
|
2005-05-26 01:31:08 +02:00
|
|
|
close that file descriptor:
|
|
|
|
.Ic exec 3\*(Gt&p; exec 3\*(Gt&-
|
2005-05-23 05:06:10 +02:00
|
|
|
.It
|
|
|
|
In order for co-processes to share a common output, the shell must keep the
|
|
|
|
write portion of the output pipe open.
|
|
|
|
This means that end-of-file will not be
|
|
|
|
detected until all co-processes sharing the co-process's output have exited
|
|
|
|
(when they all exit, the shell closes its copy of the pipe).
|
|
|
|
This can be
|
|
|
|
avoided by redirecting the output to a numbered file descriptor (as this also
|
|
|
|
causes the shell to close its copy).
|
|
|
|
Note that this behaviour is slightly
|
|
|
|
different from the original Korn shell which closes its copy of the write
|
|
|
|
portion of the co-process output when the most recently started co-process
|
|
|
|
(instead of when all sharing co-processes) exits.
|
|
|
|
.It
|
|
|
|
.Ic print -p
|
|
|
|
will ignore
|
|
|
|
.Dv SIGPIPE
|
|
|
|
signals during writes if the signal is not being trapped or ignored; the same
|
|
|
|
is true if the co-process input has been duplicated to another file descriptor
|
|
|
|
and
|
|
|
|
.Ic print -u Ns Ar n
|
|
|
|
is used.
|
|
|
|
.El
|
|
|
|
.Ss Functions
|
|
|
|
Functions are defined using either Korn shell
|
|
|
|
.Ic function Ar function-name
|
|
|
|
syntax or the Bourne/POSIX shell
|
|
|
|
.Ar function-name Ns ()
|
|
|
|
syntax (see below for the difference between the two forms).
|
|
|
|
Functions are like
|
|
|
|
.Li .-scripts
|
|
|
|
(i.e. scripts sourced using the
|
|
|
|
.Sq \&.
|
|
|
|
built-in)
|
|
|
|
in that they are executed in the current environment.
|
|
|
|
However, unlike
|
|
|
|
.Li .-scripts ,
|
|
|
|
shell arguments (i.e. positional parameters $1, $2, etc.)\&
|
|
|
|
are never visible inside them.
|
|
|
|
When the shell is determining the location of a command, functions
|
|
|
|
are searched after special built-in commands, before regular and
|
|
|
|
non-regular built-ins, and before the
|
|
|
|
.Ev PATH
|
|
|
|
is searched.
|
|
|
|
.Pp
|
|
|
|
An existing function may be deleted using
|
|
|
|
.Ic unset Fl f Ar function-name .
|
|
|
|
A list of functions can be obtained using
|
|
|
|
.Ic typeset +f
|
|
|
|
and the function definitions can be listed using
|
|
|
|
.Ic typeset -f .
|
|
|
|
The
|
|
|
|
.Ic autoload
|
|
|
|
command (which is an alias for
|
|
|
|
.Ic typeset -fu )
|
|
|
|
may be used to create undefined functions: when an undefined function is
|
|
|
|
executed, the shell searches the path specified in the
|
|
|
|
.Ev FPATH
|
2006-01-30 13:37:24 +01:00
|
|
|
parameter for a file with the same name as the function which, if found, is
|
2005-05-23 05:06:10 +02:00
|
|
|
read and executed.
|
|
|
|
If after executing the file the named function is found to
|
|
|
|
be defined, the function is executed; otherwise, the normal command search is
|
|
|
|
continued (i.e. the shell searches the regular built-in command table and
|
|
|
|
.Ev PATH ) .
|
|
|
|
Note that if a command is not found using
|
|
|
|
.Ev PATH ,
|
|
|
|
an attempt is made to autoload a function using
|
|
|
|
.Ev FPATH
|
|
|
|
(this is an undocumented feature of the original Korn shell).
|
|
|
|
.Pp
|
|
|
|
Functions can have two attributes,
|
|
|
|
.Dq trace
|
|
|
|
and
|
|
|
|
.Dq export ,
|
|
|
|
which can be set with
|
|
|
|
.Ic typeset -ft
|
|
|
|
and
|
|
|
|
.Ic typeset -fx ,
|
|
|
|
respectively.
|
|
|
|
When a traced function is executed, the shell's
|
|
|
|
.Ic xtrace
|
|
|
|
option is turned on for the function's duration; otherwise, the
|
|
|
|
.Ic xtrace
|
|
|
|
option is turned off.
|
|
|
|
The
|
|
|
|
.Dq export
|
|
|
|
attribute of functions is currently not used.
|
|
|
|
In the original Korn shell,
|
|
|
|
exported functions are visible to shell scripts that are executed.
|
|
|
|
.Pp
|
|
|
|
Since functions are executed in the current shell environment, parameter
|
|
|
|
assignments made inside functions are visible after the function completes.
|
|
|
|
If this is not the desired effect, the
|
|
|
|
.Ic typeset
|
|
|
|
command can be used inside a function to create a local parameter.
|
|
|
|
Note that special parameters (e.g.\&
|
|
|
|
.Ic \&$$ , $! )
|
|
|
|
can't be scoped in this way.
|
|
|
|
.Pp
|
|
|
|
The exit status of a function is that of the last command executed in the
|
|
|
|
function.
|
|
|
|
A function can be made to finish immediately using the
|
|
|
|
.Ic return
|
|
|
|
command; this may also be used to explicitly specify the exit status.
|
|
|
|
.Pp
|
|
|
|
Functions defined with the
|
|
|
|
.Ic function
|
|
|
|
reserved word are treated differently in the following ways from functions
|
|
|
|
defined with the
|
|
|
|
.Ic ()
|
|
|
|
notation:
|
|
|
|
.Bl -bullet
|
|
|
|
.It
|
|
|
|
The $0 parameter is set to the name of the function
|
|
|
|
(Bourne-style functions leave $0 untouched).
|
|
|
|
.It
|
|
|
|
Parameter assignments preceding function calls are not kept in the shell
|
|
|
|
environment (executing Bourne-style functions will keep assignments).
|
|
|
|
.It
|
|
|
|
.Ev OPTIND
|
|
|
|
is saved/reset and restored on entry and exit from the function so
|
|
|
|
.Ic getopts
|
|
|
|
can be used properly both inside and outside the function (Bourne-style
|
|
|
|
functions leave
|
|
|
|
.Ev OPTIND
|
|
|
|
untouched, so using
|
|
|
|
.Ic getopts
|
|
|
|
inside a function interferes with using
|
|
|
|
.Ic getopts
|
|
|
|
outside the function).
|
|
|
|
.El
|
|
|
|
.Pp
|
|
|
|
In the future, the following differences will also be added:
|
|
|
|
.Bl -bullet
|
|
|
|
.It
|
|
|
|
A separate trap/signal environment will be used during the execution of
|
|
|
|
functions.
|
|
|
|
This will mean that traps set inside a function will not affect the
|
|
|
|
shell's traps and signals that are not ignored in the shell (but may be
|
|
|
|
trapped) will have their default effect in a function.
|
|
|
|
.It
|
|
|
|
The EXIT trap, if set in a function, will be executed after the function
|
|
|
|
returns.
|
|
|
|
.El
|
|
|
|
.Ss Command execution
|
|
|
|
After evaluation of command-line arguments, redirections, and parameter
|
|
|
|
assignments, the type of command is determined: a special built-in, a
|
|
|
|
function, a regular built-in, or the name of a file to execute found using the
|
|
|
|
.Ev PATH
|
|
|
|
parameter.
|
|
|
|
The checks are made in the above order.
|
|
|
|
Special built-in commands differ from other commands in that the
|
|
|
|
.Ev PATH
|
|
|
|
parameter is not used to find them, an error during their execution can
|
|
|
|
cause a non-interactive shell to exit, and parameter assignments that are
|
|
|
|
specified before the command are kept after the command completes.
|
|
|
|
Regular built-in commands are different only in that the
|
|
|
|
.Ev PATH
|
|
|
|
parameter is not used to find them.
|
|
|
|
.Pp
|
|
|
|
The original
|
|
|
|
.Nm ksh
|
|
|
|
and POSIX differ somewhat in which commands are considered
|
|
|
|
special or regular:
|
|
|
|
.Pp
|
|
|
|
POSIX special commands
|
|
|
|
.Pp
|
|
|
|
.Ic \&. , \&: , break , continue ,
|
|
|
|
.Ic eval , exec , exit , export ,
|
|
|
|
.Ic readonly , return , set , shift ,
|
|
|
|
.Ic trap , unset
|
|
|
|
.Pp
|
|
|
|
Additional
|
|
|
|
.Nm
|
|
|
|
special commands
|
|
|
|
.Pp
|
|
|
|
.Ic builtin , times , typeset
|
|
|
|
.Pp
|
|
|
|
Very special commands
|
|
|
|
.Pq non-POSIX
|
|
|
|
.Pp
|
|
|
|
.Ic alias , readonly , set , typeset
|
|
|
|
.Pp
|
|
|
|
POSIX regular commands
|
|
|
|
.Pp
|
|
|
|
.Ic alias , bg , cd , command ,
|
|
|
|
.Ic false , fc , fg , getopts ,
|
|
|
|
.Ic jobs , kill , read , true ,
|
|
|
|
.Ic umask , unalias , wait
|
|
|
|
.Pp
|
|
|
|
Additional
|
|
|
|
.Nm
|
|
|
|
regular commands
|
|
|
|
.Pp
|
2005-10-21 14:41:56 +02:00
|
|
|
.Ic \&[ , echo , let , mknod ,
|
|
|
|
.Ic print , pwd , test , ulimit ,
|
|
|
|
.Ic whence
|
2005-05-23 05:06:10 +02:00
|
|
|
.Pp
|
|
|
|
In the future, the additional
|
|
|
|
.Nm
|
|
|
|
special and regular commands may be treated
|
|
|
|
differently from the POSIX special and regular commands.
|
|
|
|
.Pp
|
|
|
|
Once the type of command has been determined, any command-line parameter
|
|
|
|
assignments are performed and exported for the duration of the command.
|
|
|
|
.Pp
|
|
|
|
The following describes the special and regular built-in commands:
|
|
|
|
.Pp
|
|
|
|
.Bl -tag -width Ds -compact
|
|
|
|
.It Ic \&. Ar file Op Ar arg ...
|
|
|
|
Execute the commands in
|
|
|
|
.Ar file
|
|
|
|
in the current environment.
|
|
|
|
The file is searched for in the directories of
|
|
|
|
.Ev PATH .
|
|
|
|
If arguments are given, the positional parameters may be used to access them
|
|
|
|
while
|
|
|
|
.Ar file
|
|
|
|
is being executed.
|
|
|
|
If no arguments are given, the positional parameters are
|
|
|
|
those of the environment the command is used in.
|
|
|
|
.Pp
|
|
|
|
.It Ic \&: Op Ar ...
|
|
|
|
The null command.
|
|
|
|
Exit status is set to zero.
|
|
|
|
.Pp
|
|
|
|
.It Xo Ic alias
|
|
|
|
.Oo Fl d \*(Ba t Oo Fl r Oc \*(Ba
|
|
|
|
.Cm +-x Oc
|
|
|
|
.Op Fl p
|
|
|
|
.Op Cm +
|
|
|
|
.Oo Ar name
|
|
|
|
.Op Ns = Ns Ar value
|
|
|
|
.Ar ... Oc
|
|
|
|
.Xc
|
|
|
|
Without arguments,
|
|
|
|
.Ic alias
|
|
|
|
lists all aliases.
|
|
|
|
For any name without a value, the existing alias is listed.
|
|
|
|
Any name with a value defines an alias (see
|
|
|
|
.Sx Aliases
|
|
|
|
above).
|
|
|
|
.Pp
|
|
|
|
When listing aliases, one of two formats is used.
|
|
|
|
Normally, aliases are listed as
|
|
|
|
.Ar name Ns = Ns Ar value ,
|
|
|
|
where
|
|
|
|
.Ar value
|
|
|
|
is quoted.
|
|
|
|
If options were preceded with
|
|
|
|
.Ql + ,
|
|
|
|
or a lone
|
|
|
|
.Ql +
|
|
|
|
is given on the command line, only
|
|
|
|
.Ar name
|
|
|
|
is printed.
|
|
|
|
.Pp
|
|
|
|
The
|
|
|
|
.Fl d
|
2006-01-30 13:37:24 +01:00
|
|
|
option causes directory aliases which are used in tilde expansion to be
|
2005-05-23 05:06:10 +02:00
|
|
|
listed or set (see
|
|
|
|
.Sx Tilde expansion
|
|
|
|
above).
|
|
|
|
.Pp
|
|
|
|
If the
|
|
|
|
.Fl p
|
|
|
|
option is used, each alias is prefixed with the string
|
|
|
|
.Dq alias\ \& .
|
|
|
|
.Pp
|
|
|
|
The
|
|
|
|
.Fl t
|
|
|
|
option indicates that tracked aliases are to be listed/set (values specified on
|
|
|
|
the command line are ignored for tracked aliases).
|
|
|
|
The
|
|
|
|
.Fl r
|
|
|
|
option indicates that all tracked aliases are to be reset.
|
|
|
|
.Pp
|
|
|
|
The
|
|
|
|
.Fl x
|
|
|
|
option sets
|
|
|
|
.Pq Ic +x No clears
|
|
|
|
the export attribute of an alias, or, if no names are given, lists the aliases
|
|
|
|
with the export attribute (exporting an alias has no effect).
|
|
|
|
.Pp
|
|
|
|
.It Ic bg Op Ar job ...
|
|
|
|
Resume the specified stopped job(s) in the background.
|
|
|
|
If no jobs are specified,
|
|
|
|
.Ic %+
|
|
|
|
is assumed.
|
|
|
|
See
|
|
|
|
.Sx Job control
|
|
|
|
below for more information.
|
|
|
|
.Pp
|
|
|
|
.It Ic bind Op Fl l
|
|
|
|
The current bindings are listed.
|
|
|
|
If the
|
|
|
|
.Fl l
|
|
|
|
flag is given,
|
|
|
|
.Ic bind
|
|
|
|
instead lists the names of the functions to which keys may be bound.
|
|
|
|
See
|
|
|
|
.Sx Emacs editing mode
|
|
|
|
for more information.
|
|
|
|
.Pp
|
|
|
|
.It Xo Ic bind Op Fl m
|
|
|
|
.Ar string Ns = Ns Op Ar substitute
|
|
|
|
.Ar ...
|
|
|
|
.Xc
|
|
|
|
.It Xo Ic bind
|
|
|
|
.Ar string Ns = Ns Op Ar editing-command
|
|
|
|
.Ar ...
|
|
|
|
.Xc
|
|
|
|
The specified editing command is bound to the given
|
|
|
|
.Ar string ,
|
|
|
|
which should consist of a control character
|
2006-08-02 15:32:18 +02:00
|
|
|
optionally preceded by one of the two prefix characters
|
|
|
|
and optionally succeded by a tilde character.
|
2005-05-23 05:06:10 +02:00
|
|
|
Future input of the
|
|
|
|
.Ar string
|
|
|
|
will cause the editing command to be immediately invoked.
|
|
|
|
If the
|
|
|
|
.Fl m
|
|
|
|
flag is given, the specified input
|
|
|
|
.Ar string
|
|
|
|
will afterwards be immediately replaced by the given
|
|
|
|
.Ar substitute
|
2006-01-30 13:37:24 +01:00
|
|
|
string which may contain editing commands.
|
2006-08-02 15:32:18 +02:00
|
|
|
If a tilde postfix is given, a tilde trailing the one or
|
|
|
|
two prefices and the control character is ignored, any
|
|
|
|
other trailing character will be processed afterwards.
|
2005-05-23 05:06:10 +02:00
|
|
|
.Pp
|
|
|
|
Control characters may be written using caret notation
|
|
|
|
i.e. ^X represents Control-X.
|
|
|
|
Note that although only two prefix characters (usually ESC and ^X)
|
|
|
|
are supported, some multi-character sequences can be supported.
|
|
|
|
.Pp
|
2006-08-02 16:00:19 +02:00
|
|
|
The following default bindings show how the arrow keys, the home, end and
|
|
|
|
delete key on a BSD wsvt25, xterm-xfree86 or GNU screen terminal are bound
|
2005-05-23 05:06:10 +02:00
|
|
|
(of course some escape sequences won't work out quite this nicely):
|
|
|
|
.Bd -literal -offset indent
|
|
|
|
bind '^[['=prefix-2
|
|
|
|
bind '^XA'=up-history
|
|
|
|
bind '^XB'=down-history
|
|
|
|
bind '^XC'=forward-char
|
|
|
|
bind '^XD'=backward-char
|
2006-08-02 15:32:18 +02:00
|
|
|
bind '^X1~'=beginning-of-line
|
2006-08-02 16:00:19 +02:00
|
|
|
bind '^X7~'=beginning-of-line
|
|
|
|
bind '^XH'=beginning-of-line
|
2006-08-02 15:32:18 +02:00
|
|
|
bind '^X4~'=end-of-line
|
2006-08-02 16:00:19 +02:00
|
|
|
bind '^X8~'=end-of-line
|
|
|
|
bind '^XF'=end-of-line
|
2006-08-02 16:02:55 +02:00
|
|
|
bind '^X3~'=delete-char-forward
|
2005-05-23 05:06:10 +02:00
|
|
|
.Ed
|
|
|
|
.Pp
|
|
|
|
.It Ic break Op Ar level
|
|
|
|
Exit the
|
|
|
|
.Ar level Ns th
|
|
|
|
inner-most
|
|
|
|
.Ic for ,
|
|
|
|
.Ic select ,
|
|
|
|
.Ic until ,
|
|
|
|
or
|
|
|
|
.Ic while
|
|
|
|
loop.
|
|
|
|
.Ar level
|
|
|
|
defaults to 1.
|
|
|
|
.Pp
|
|
|
|
.It Ic builtin Ar command Op Ar arg ...
|
|
|
|
Execute the built-in command
|
|
|
|
.Ar command .
|
|
|
|
.Pp
|
|
|
|
.It Xo
|
|
|
|
.Ic cd
|
|
|
|
.Op Fl LP
|
|
|
|
.Op Ar dir
|
|
|
|
.Xc
|
|
|
|
Set the working directory to
|
|
|
|
.Ar dir .
|
|
|
|
If the parameter
|
|
|
|
.Ev CDPATH
|
|
|
|
is set, it lists the search path for the directory containing
|
|
|
|
.Ar dir .
|
|
|
|
A
|
|
|
|
.Dv NULL
|
|
|
|
path means the current directory.
|
|
|
|
If
|
|
|
|
.Ar dir
|
|
|
|
is found in any component of the
|
|
|
|
.Ev CDPATH
|
|
|
|
search path other than the
|
|
|
|
.Dv NULL
|
|
|
|
path, the name of the new working directory will be written to standard output.
|
|
|
|
If
|
|
|
|
.Ar dir
|
|
|
|
is missing, the home directory
|
|
|
|
.Ev HOME
|
|
|
|
is used.
|
|
|
|
If
|
|
|
|
.Ar dir
|
|
|
|
is
|
|
|
|
.Ql - ,
|
|
|
|
the previous working directory is used (see the
|
|
|
|
.Ev OLDPWD
|
|
|
|
parameter).
|
|
|
|
.Pp
|
|
|
|
If the
|
|
|
|
.Fl L
|
|
|
|
option (logical path) is used or if the
|
|
|
|
.Ic physical
|
|
|
|
option isn't set (see the
|
|
|
|
.Ic set
|
|
|
|
command below), references to
|
|
|
|
.Sq ..
|
|
|
|
in
|
|
|
|
.Ar dir
|
|
|
|
are relative to the path used to get to the directory.
|
|
|
|
If the
|
|
|
|
.Fl P
|
|
|
|
option (physical path) is used or if the
|
|
|
|
.Ic physical
|
|
|
|
option is set,
|
|
|
|
.Sq ..
|
|
|
|
is relative to the filesystem directory tree.
|
|
|
|
The
|
|
|
|
.Ev PWD
|
|
|
|
and
|
|
|
|
.Ev OLDPWD
|
|
|
|
parameters are updated to reflect the current and old working directory,
|
|
|
|
respectively.
|
|
|
|
.Pp
|
|
|
|
.It Xo
|
|
|
|
.Ic cd
|
|
|
|
.Op Fl LP
|
|
|
|
.Ar old new
|
|
|
|
.Xc
|
|
|
|
The string
|
|
|
|
.Ar new
|
|
|
|
is substituted for
|
|
|
|
.Ar old
|
|
|
|
in the current directory, and the shell attempts to change to the new
|
|
|
|
directory.
|
|
|
|
.Pp
|
|
|
|
.It Xo
|
|
|
|
.Ic command
|
|
|
|
.Op Fl pVv
|
|
|
|
.Ar cmd
|
|
|
|
.Op Ar arg ...
|
|
|
|
.Xc
|
|
|
|
If neither the
|
|
|
|
.Fl v
|
|
|
|
nor
|
|
|
|
.Fl V
|
|
|
|
option is given,
|
|
|
|
.Ar cmd
|
|
|
|
is executed exactly as if
|
|
|
|
.Ic command
|
|
|
|
had not been specified, with two exceptions:
|
|
|
|
firstly,
|
|
|
|
.Ar cmd
|
|
|
|
cannot be a shell function;
|
|
|
|
and secondly, special built-in commands lose their specialness
|
|
|
|
(i.e. redirection and utility errors do not cause the shell to
|
|
|
|
exit, and command assignments are not permanent).
|
|
|
|
.Pp
|
|
|
|
If the
|
|
|
|
.Fl p
|
|
|
|
option is given, a default search path is used instead of the current value of
|
|
|
|
.Ev PATH
|
|
|
|
(the actual value of the default path is system dependent: on
|
|
|
|
POSIX-ish systems, it is the value returned by
|
|
|
|
.Ic getconf CS_PATH ) .
|
|
|
|
.Pp
|
|
|
|
If the
|
|
|
|
.Fl v
|
|
|
|
option is given, instead of executing
|
|
|
|
.Ar cmd ,
|
|
|
|
information about what would be executed is given (and the same is done for
|
|
|
|
.Ar arg ... ) .
|
|
|
|
For special and regular built-in commands and functions, their names are simply
|
|
|
|
printed; for aliases, a command that defines them is printed; and for commands
|
|
|
|
found by searching the
|
|
|
|
.Ev PATH
|
|
|
|
parameter, the full path of the command is printed.
|
|
|
|
If no command is found
|
|
|
|
(i.e. the path search fails), nothing is printed and
|
|
|
|
.Ic command
|
|
|
|
exits with a non-zero status.
|
|
|
|
The
|
|
|
|
.Fl V
|
|
|
|
option is like the
|
|
|
|
.Fl v
|
|
|
|
option, except it is more verbose.
|
|
|
|
.Pp
|
|
|
|
.It Ic continue Op Ar level
|
|
|
|
Jumps to the beginning of the
|
|
|
|
.Ar level Ns th
|
|
|
|
inner-most
|
|
|
|
.Ic for ,
|
|
|
|
.Ic select ,
|
|
|
|
.Ic until ,
|
|
|
|
or
|
|
|
|
.Ic while
|
|
|
|
loop.
|
|
|
|
.Ar level
|
|
|
|
defaults to 1.
|
|
|
|
.Pp
|
|
|
|
.It Xo
|
|
|
|
.Ic echo
|
|
|
|
.Op Fl Een
|
|
|
|
.Op Ar arg ...
|
|
|
|
.Xc
|
|
|
|
Prints its arguments (separated by spaces) followed by a newline, to the
|
|
|
|
standard output.
|
|
|
|
The newline is suppressed if any of the arguments contain the
|
|
|
|
backslash sequence
|
|
|
|
.Ql \ec .
|
|
|
|
See the
|
|
|
|
.Ic print
|
|
|
|
command below for a list of other backslash sequences that are recognised.
|
|
|
|
.Pp
|
|
|
|
The options are provided for compatibility with
|
|
|
|
.Bx
|
|
|
|
shell scripts.
|
|
|
|
The
|
|
|
|
.Fl n
|
|
|
|
option suppresses the trailing newline,
|
|
|
|
.Fl e
|
|
|
|
enables backslash interpretation (a no-op, since this is normally done), and
|
|
|
|
.Fl E
|
|
|
|
suppresses backslash interpretation.
|
|
|
|
.Pp
|
|
|
|
.It Ic eval Ar command ...
|
|
|
|
The arguments are concatenated (with spaces between them) to form a single
|
|
|
|
string which the shell then parses and executes in the current environment.
|
|
|
|
.Pp
|
|
|
|
.It Xo
|
|
|
|
.Ic exec
|
|
|
|
.Op Ar command Op Ar arg ...
|
|
|
|
.Xc
|
|
|
|
The command is executed without forking, replacing the shell process.
|
|
|
|
.Pp
|
|
|
|
If no command is given except for I/O redirection, the I/O redirection is
|
|
|
|
permanent and the shell is
|
|
|
|
not replaced.
|
|
|
|
Any file descriptors greater than 2 which are opened or
|
|
|
|
.Xr dup 2 Ns 'd
|
|
|
|
in this way are not made available to other executed commands (i.e. commands
|
|
|
|
that are not built-in to the shell).
|
|
|
|
Note that the Bourne shell differs here;
|
|
|
|
it does pass these file descriptors on.
|
|
|
|
.Pp
|
|
|
|
.It Ic exit Op Ar status
|
|
|
|
The shell exits with the specified exit status.
|
|
|
|
If
|
|
|
|
.Ar status
|
|
|
|
is not specified, the exit status is the current value of the
|
|
|
|
.Ic $?\&
|
|
|
|
parameter.
|
|
|
|
.Pp
|
|
|
|
.It Xo
|
|
|
|
.Ic export
|
|
|
|
.Op Fl p
|
|
|
|
.Op Ar parameter Ns Op = Ns Ar value
|
|
|
|
.Xc
|
|
|
|
Sets the export attribute of the named parameters.
|
|
|
|
Exported parameters are passed in the environment to executed commands.
|
|
|
|
If values are specified, the named parameters are also assigned.
|
|
|
|
.Pp
|
|
|
|
If no parameters are specified, the names of all parameters with the export
|
|
|
|
attribute are printed one per line, unless the
|
|
|
|
.Fl p
|
|
|
|
option is used, in which case
|
|
|
|
.Ic export
|
|
|
|
commands defining all exported parameters, including their values, are printed.
|
|
|
|
.Pp
|
|
|
|
.It Ic false
|
|
|
|
A command that exits with a non-zero status.
|
|
|
|
.Pp
|
|
|
|
.It Xo
|
|
|
|
.Ic fc
|
|
|
|
.Oo Fl e Ar editor \*(Ba
|
|
|
|
.Fl l Op Fl n Oc
|
|
|
|
.Op Fl r
|
|
|
|
.Op Ar first Op Ar last
|
|
|
|
.Xc
|
|
|
|
.Ar first
|
|
|
|
and
|
|
|
|
.Ar last
|
|
|
|
select commands from the history.
|
|
|
|
Commands can be selected by history number
|
|
|
|
or a string specifying the most recent command starting with that string.
|
|
|
|
The
|
|
|
|
.Fl l
|
|
|
|
option lists the command on standard output, and
|
|
|
|
.Fl n
|
|
|
|
inhibits the default command numbers.
|
|
|
|
The
|
|
|
|
.Fl r
|
|
|
|
option reverses the order of the list.
|
|
|
|
Without
|
|
|
|
.Fl l ,
|
|
|
|
the selected commands are edited by the editor specified with the
|
|
|
|
.Fl e
|
|
|
|
option, or if no
|
|
|
|
.Fl e
|
|
|
|
is specified, the editor specified by the
|
|
|
|
.Ev FCEDIT
|
|
|
|
parameter (if this parameter is not set,
|
|
|
|
.Pa /bin/ed
|
|
|
|
is used), and then executed by the shell.
|
|
|
|
.Pp
|
|
|
|
.It Xo
|
|
|
|
.Ic fc
|
|
|
|
.Cm -e - \*(Ba Fl s
|
|
|
|
.Op Fl g
|
|
|
|
.Op Ar old Ns = Ns Ar new
|
|
|
|
.Op Ar prefix
|
|
|
|
.Xc
|
|
|
|
Re-execute the selected command (the previous command by default) after
|
|
|
|
performing the optional substitution of
|
|
|
|
.Ar old
|
|
|
|
with
|
|
|
|
.Ar new .
|
|
|
|
If
|
|
|
|
.Fl g
|
|
|
|
is specified, all occurrences of
|
|
|
|
.Ar old
|
|
|
|
are replaced with
|
|
|
|
.Ar new .
|
|
|
|
The meaning of
|
|
|
|
.Cm -e -
|
|
|
|
and
|
|
|
|
.Fl s
|
|
|
|
is identical: re-execute the selected command without invoking an editor.
|
|
|
|
This command is usually accessed with the predefined
|
|
|
|
.Ic alias r='fc -e -' .
|
|
|
|
.Pp
|
|
|
|
.It Ic fg Op Ar job ...
|
|
|
|
Resume the specified job(s) in the foreground.
|
|
|
|
If no jobs are specified,
|
|
|
|
.Ic %+
|
|
|
|
is assumed.
|
|
|
|
See
|
|
|
|
.Sx Job control
|
|
|
|
below for more information.
|
|
|
|
.Pp
|
|
|
|
.It Xo
|
|
|
|
.Ic getopts
|
|
|
|
.Ar optstring name
|
|
|
|
.Op Ar arg ...
|
|
|
|
.Xc
|
|
|
|
Used by shell procedures to parse the specified arguments (or positional
|
|
|
|
parameters, if no arguments are given) and to check for legal options.
|
|
|
|
.Ar optstring
|
|
|
|
contains the option letters that
|
|
|
|
.Ic getopts
|
|
|
|
is to recognise.
|
|
|
|
If a letter is followed by a colon, the option is expected to
|
|
|
|
have an argument.
|
|
|
|
Options that do not take arguments may be grouped in a single argument.
|
|
|
|
If an option takes an argument and the option character is not the
|
|
|
|
last character of the argument it is found in, the remainder of the argument is
|
|
|
|
taken to be the option's argument; otherwise, the next argument is the option's
|
|
|
|
argument.
|
|
|
|
.Pp
|
|
|
|
Each time
|
|
|
|
.Ic getopts
|
|
|
|
is invoked, it places the next option in the shell parameter
|
|
|
|
.Ar name
|
2006-08-01 16:09:20 +02:00
|
|
|
and the index of the argument to be processed by the next call to
|
|
|
|
.Ic getopts
|
|
|
|
in the shell parameter
|
2005-05-23 05:06:10 +02:00
|
|
|
.Ev OPTIND .
|
|
|
|
If the option was introduced with a
|
|
|
|
.Ql + ,
|
|
|
|
the option placed in
|
|
|
|
.Ar name
|
|
|
|
is prefixed with a
|
|
|
|
.Ql + .
|
|
|
|
When an option requires an argument,
|
|
|
|
.Ic getopts
|
|
|
|
places it in the shell parameter
|
|
|
|
.Ev OPTARG .
|
|
|
|
.Pp
|
|
|
|
When an illegal option or a missing option argument is encountered, a question
|
|
|
|
mark or a colon is placed in
|
|
|
|
.Ar name
|
|
|
|
(indicating an illegal option or missing argument, respectively) and
|
|
|
|
.Ev OPTARG
|
|
|
|
is set to the option character that caused the problem.
|
|
|
|
Furthermore, if
|
|
|
|
.Ar optstring
|
|
|
|
does not begin with a colon, a question mark is placed in
|
|
|
|
.Ar name ,
|
|
|
|
.Ev OPTARG
|
|
|
|
is unset, and an error message is printed to standard error.
|
|
|
|
.Pp
|
|
|
|
When the end of the options is encountered,
|
|
|
|
.Ic getopts
|
|
|
|
exits with a non-zero exit status.
|
|
|
|
Options end at the first (non-option
|
|
|
|
argument) argument that does not start with a
|
|
|
|
.Ql - ,
|
|
|
|
or when a
|
|
|
|
.Ql --
|
|
|
|
argument is encountered.
|
|
|
|
.Pp
|
|
|
|
Option parsing can be reset by setting
|
|
|
|
.Ev OPTIND
|
|
|
|
to 1 (this is done automatically whenever the shell or a shell procedure is
|
|
|
|
invoked).
|
|
|
|
.Pp
|
|
|
|
Warning: Changing the value of the shell parameter
|
|
|
|
.Ev OPTIND
|
|
|
|
to a value other than 1, or parsing different sets of arguments without
|
|
|
|
resetting
|
|
|
|
.Ev OPTIND ,
|
|
|
|
may lead to unexpected results.
|
|
|
|
.Pp
|
|
|
|
.It Xo
|
|
|
|
.Ic hash
|
|
|
|
.Op Fl r
|
|
|
|
.Op Ar name ...
|
|
|
|
.Xc
|
|
|
|
Without arguments, any hashed executable command pathnames are listed.
|
|
|
|
The
|
|
|
|
.Fl r
|
|
|
|
option causes all hashed commands to be removed from the hash table.
|
|
|
|
Each
|
|
|
|
.Ar name
|
|
|
|
is searched as if it were a command name and added to the hash table if it is
|
|
|
|
an executable command.
|
|
|
|
.Pp
|
|
|
|
.It Xo
|
|
|
|
.Ic jobs
|
|
|
|
.Op Fl lnp
|
|
|
|
.Op Ar job ...
|
|
|
|
.Xc
|
|
|
|
Display information about the specified job(s); if no jobs are specified, all
|
|
|
|
jobs are displayed.
|
|
|
|
The
|
|
|
|
.Fl n
|
|
|
|
option causes information to be displayed only for jobs that have changed
|
|
|
|
state since the last notification.
|
|
|
|
If the
|
|
|
|
.Fl l
|
|
|
|
option is used, the process ID of each process in a job is also listed.
|
|
|
|
The
|
|
|
|
.Fl p
|
|
|
|
option causes only the process group of each job to be printed.
|
|
|
|
See
|
|
|
|
.Sx Job control
|
|
|
|
below for the format of
|
|
|
|
.Ar job
|
|
|
|
and the displayed job.
|
|
|
|
.Pp
|
|
|
|
.It Xo
|
|
|
|
.Ic kill
|
|
|
|
.Oo Fl s Ar signame \*(Ba
|
|
|
|
.No - Ns Ar signum \*(Ba
|
|
|
|
.No - Ns Ar signame Oc
|
|
|
|
.No { Ar job \*(Ba pid \*(Ba pgrp No }
|
|
|
|
.Ar ...
|
|
|
|
.Xc
|
|
|
|
Send the specified signal to the specified jobs, process IDs, or process
|
|
|
|
groups.
|
|
|
|
If no signal is specified, the
|
|
|
|
.Dv TERM
|
|
|
|
signal is sent.
|
|
|
|
If a job is specified, the signal is sent to the job's process group.
|
|
|
|
See
|
|
|
|
.Sx Job control
|
|
|
|
below for the format of
|
|
|
|
.Ar job .
|
|
|
|
.Pp
|
|
|
|
.It Xo
|
|
|
|
.Ic kill
|
|
|
|
.Fl l
|
|
|
|
.Op Ar exit-status ...
|
|
|
|
.Xc
|
|
|
|
Print the signal name corresponding to
|
|
|
|
.Ar exit-status .
|
|
|
|
If no arguments are specified, a list of all the signals, their numbers, and
|
|
|
|
a short description of them are printed.
|
|
|
|
.Pp
|
|
|
|
.It Ic let Op Ar expression ...
|
|
|
|
Each expression is evaluated (see
|
|
|
|
.Sx Arithmetic expressions
|
|
|
|
above).
|
|
|
|
If all expressions are successfully evaluated, the exit status is 0 (1)
|
|
|
|
if the last expression evaluated to non-zero (zero).
|
|
|
|
If an error occurs during
|
|
|
|
the parsing or evaluation of an expression, the exit status is greater than 1.
|
|
|
|
Since expressions may need to be quoted,
|
|
|
|
.No (( Ar expr No ))
|
|
|
|
is syntactic sugar for
|
|
|
|
.No let \&" Ns Ar expr Ns \&" .
|
|
|
|
.Pp
|
|
|
|
.It Xo
|
2005-10-21 14:41:56 +02:00
|
|
|
.Ic mknod
|
|
|
|
.Op Fl m Ar mode
|
|
|
|
.Ar name
|
2006-01-27 11:58:36 +01:00
|
|
|
.Op Cm c \*(Ba Cm b
|
2005-10-21 14:41:56 +02:00
|
|
|
.Ar major minor
|
|
|
|
.Xc
|
|
|
|
.It Xo
|
|
|
|
.Ic mknod
|
|
|
|
.Op Fl m Ar mode
|
|
|
|
.Ar name
|
|
|
|
.Cm p
|
|
|
|
.Xc
|
|
|
|
Create a device special file.
|
|
|
|
The file type may be
|
|
|
|
.Cm b
|
|
|
|
(block type device),
|
|
|
|
.Cm c
|
|
|
|
(character type device),
|
|
|
|
or
|
|
|
|
.Cm p
|
|
|
|
(named pipe).
|
|
|
|
The file created may be modified according to its
|
|
|
|
.Ar mode
|
|
|
|
(via the
|
|
|
|
.Fl m
|
|
|
|
option),
|
|
|
|
.Ar major
|
|
|
|
(major device number),
|
|
|
|
and
|
|
|
|
.Ar minor
|
|
|
|
(minor device number).
|
|
|
|
.Pp
|
|
|
|
See
|
|
|
|
.Xr mknod 8
|
|
|
|
for further information.
|
|
|
|
.Pp
|
|
|
|
.It Xo
|
2005-05-23 05:06:10 +02:00
|
|
|
.Ic print
|
|
|
|
.Oo Fl nprsu Ns Oo Ar n Oc \*(Ba
|
|
|
|
.Fl R Op Fl en Oc
|
|
|
|
.Op Ar argument ...
|
|
|
|
.Xc
|
|
|
|
.Ic print
|
|
|
|
prints its arguments on the standard output, separated by spaces and
|
|
|
|
terminated with a newline.
|
|
|
|
The
|
|
|
|
.Fl n
|
|
|
|
option suppresses the newline.
|
|
|
|
By default, certain C escapes are translated.
|
|
|
|
These include
|
|
|
|
.Ql \eb ,
|
|
|
|
.Ql \ef ,
|
|
|
|
.Ql \en ,
|
|
|
|
.Ql \er ,
|
|
|
|
.Ql \et ,
|
|
|
|
.Ql \ev ,
|
|
|
|
and
|
|
|
|
.Ql \e0###
|
|
|
|
.Po
|
|
|
|
.Ql #
|
|
|
|
is an octal digit, of which there may be 0 to 3
|
|
|
|
.Pc .
|
|
|
|
.Ql \ec
|
|
|
|
is equivalent to using the
|
|
|
|
.Fl n
|
|
|
|
option.
|
|
|
|
.Ql \e
|
|
|
|
expansion may be inhibited with the
|
|
|
|
.Fl r
|
|
|
|
option.
|
|
|
|
The
|
|
|
|
.Fl s
|
|
|
|
option prints to the history file instead of standard output; the
|
|
|
|
.Fl u
|
|
|
|
option prints to file descriptor
|
|
|
|
.Ar n
|
|
|
|
.Po
|
|
|
|
.Ar n
|
|
|
|
defaults to 1 if omitted
|
|
|
|
.Pc ;
|
|
|
|
and the
|
|
|
|
.Fl p
|
|
|
|
option prints to the co-process (see
|
|
|
|
.Sx Co-processes
|
|
|
|
above).
|
|
|
|
.Pp
|
|
|
|
The
|
|
|
|
.Fl R
|
|
|
|
option is used to emulate, to some degree, the
|
|
|
|
.Bx
|
|
|
|
.Xr echo 1
|
2006-01-30 13:37:24 +01:00
|
|
|
command which does not process
|
2005-05-23 05:06:10 +02:00
|
|
|
.Ql \e
|
|
|
|
sequences unless the
|
|
|
|
.Fl e
|
|
|
|
option is given.
|
|
|
|
As above, the
|
|
|
|
.Fl n
|
|
|
|
option suppresses the trailing newline.
|
|
|
|
.Pp
|
|
|
|
.It Ic pwd Op Fl LP
|
|
|
|
Print the present working directory.
|
|
|
|
If the
|
|
|
|
.Fl L
|
|
|
|
option is used or if the
|
|
|
|
.Ic physical
|
|
|
|
option isn't set (see the
|
|
|
|
.Ic set
|
|
|
|
command below), the logical path is printed (i.e. the path used to
|
|
|
|
.Ic cd
|
|
|
|
to the current directory).
|
|
|
|
If the
|
|
|
|
.Fl P
|
|
|
|
option (physical path) is used or if the
|
|
|
|
.Ic physical
|
|
|
|
option is set, the path determined from the filesystem (by following
|
|
|
|
.Sq ..
|
|
|
|
directories to the root directory) is printed.
|
|
|
|
.Pp
|
|
|
|
.It Xo
|
|
|
|
.Ic read
|
|
|
|
.Op Fl prsu Ns Op Ar n
|
|
|
|
.Op Ar parameter ...
|
|
|
|
.Xc
|
|
|
|
Reads a line of input from the standard input, separates the line into fields
|
|
|
|
using the
|
|
|
|
.Ev IFS
|
|
|
|
parameter (see
|
|
|
|
.Sx Substitution
|
|
|
|
above), and assigns each field to the specified parameters.
|
|
|
|
If there are more parameters than fields, the extra parameters are set to
|
|
|
|
.Dv NULL ,
|
|
|
|
or alternatively, if there are more fields than parameters, the last parameter
|
|
|
|
is assigned the remaining fields (inclusive of any separating spaces).
|
|
|
|
If no parameters are specified, the
|
|
|
|
.Ev REPLY
|
|
|
|
parameter is used.
|
|
|
|
If the input line ends in a backslash and the
|
|
|
|
.Fl r
|
|
|
|
option was not used, the backslash and the newline are stripped and more input
|
|
|
|
is read.
|
|
|
|
If no input is read,
|
|
|
|
.Ic read
|
|
|
|
exits with a non-zero status.
|
|
|
|
.Pp
|
|
|
|
The first parameter may have a question mark and a string appended to it, in
|
|
|
|
which case the string is used as a prompt (printed to standard error before
|
|
|
|
any input is read) if the input is a
|
|
|
|
.Xr tty 4
|
|
|
|
(e.g.\&
|
|
|
|
.Ic read nfoo?'number of foos: ' ) .
|
|
|
|
.Pp
|
|
|
|
The
|
|
|
|
.Fl u Ns Ar n
|
|
|
|
and
|
|
|
|
.Fl p
|
|
|
|
options cause input to be read from file descriptor
|
|
|
|
.Ar n
|
|
|
|
.Pf ( Ar n
|
|
|
|
defaults to 0 if omitted)
|
|
|
|
or the current co-process (see
|
|
|
|
.Sx Co-processes
|
|
|
|
above for comments on this), respectively.
|
|
|
|
If the
|
|
|
|
.Fl s
|
|
|
|
option is used, input is saved to the history file.
|
|
|
|
.Pp
|
2006-01-27 11:58:36 +01:00
|
|
|
Another handy set of tricks:
|
|
|
|
If
|
|
|
|
.Ic read
|
|
|
|
is run in a loop such as
|
|
|
|
.Ic while read foo; do ...; done
|
|
|
|
then leading whitespace will be removed (IFS) and backslashes processed
|
|
|
|
.Pf ( Fl r ) .
|
|
|
|
You might want to use
|
|
|
|
.Ic while IFS= read -r foo; do ...; done
|
|
|
|
for pristine I/O (variable splitting, as in
|
|
|
|
.Ic while IFS= read foo bar; do ...; done
|
|
|
|
is not possible though).
|
|
|
|
.Pp
|
|
|
|
The inner loop will be executed in a subshell and variable changes
|
|
|
|
cannot be propagated if executed in a pipeline:
|
|
|
|
.Bd -literal -offset indent
|
|
|
|
foo \*(Ba bar \*(Ba while read foo; do ...; done
|
|
|
|
.Ed
|
|
|
|
.Pp
|
|
|
|
Use co-processes instead:
|
|
|
|
.Bd -literal -offset indent
|
|
|
|
foo \*(Ba bar \*(Ba&
|
|
|
|
while read -p foo; do ...; done
|
|
|
|
exec 3\*(Gt&p; exec 3\*(Gt&-
|
|
|
|
.Ed
|
|
|
|
.Pp
|
2005-05-23 05:06:10 +02:00
|
|
|
.It Xo
|
|
|
|
.Ic readonly
|
|
|
|
.Op Fl p
|
|
|
|
.Oo Ar parameter
|
|
|
|
.Op Ns = Ns Ar value
|
|
|
|
.Ar ... Oc
|
|
|
|
.Xc
|
|
|
|
Sets the read-only attribute of the named parameters.
|
|
|
|
If values are given,
|
|
|
|
parameters are set to them before setting the attribute.
|
|
|
|
Once a parameter is
|
|
|
|
made read-only, it cannot be unset and its value cannot be changed.
|
|
|
|
.Pp
|
|
|
|
If no parameters are specified, the names of all parameters with the read-only
|
|
|
|
attribute are printed one per line, unless the
|
|
|
|
.Fl p
|
|
|
|
option is used, in which case
|
|
|
|
.Ic readonly
|
|
|
|
commands defining all read-only parameters, including their values, are
|
|
|
|
printed.
|
|
|
|
.Pp
|
|
|
|
.It Ic return Op Ar status
|
|
|
|
Returns from a function or
|
|
|
|
.Ic .\&
|
|
|
|
script, with exit status
|
|
|
|
.Ar status .
|
|
|
|
If no
|
|
|
|
.Ar status
|
|
|
|
is given, the exit status of the last executed command is used.
|
|
|
|
If used outside of a function or
|
|
|
|
.Ic .\&
|
|
|
|
script, it has the same effect as
|
|
|
|
.Ic exit .
|
|
|
|
Note that
|
|
|
|
.Nm
|
|
|
|
treats both profile and
|
|
|
|
.Ev ENV
|
|
|
|
files as
|
|
|
|
.Ic .\&
|
|
|
|
scripts, while the original Korn shell only treats profiles as
|
|
|
|
.Ic .\&
|
|
|
|
scripts.
|
|
|
|
.Pp
|
|
|
|
.It Xo
|
|
|
|
.Ic set Op Ic +-abCefhkmnpsuvXx
|
|
|
|
.Op Ic +-o Ar option
|
|
|
|
.Op Ic +-A Ar name
|
|
|
|
.Op Fl -
|
|
|
|
.Op Ar arg ...
|
|
|
|
.Xc
|
|
|
|
The
|
|
|
|
.Ic set
|
|
|
|
command can be used to set
|
|
|
|
.Pq Ic -
|
|
|
|
or clear
|
|
|
|
.Pq Ic +
|
|
|
|
shell options, set the positional parameters, or set an array parameter.
|
|
|
|
Options can be changed using the
|
|
|
|
.Cm +-o Ar option
|
|
|
|
syntax, where
|
|
|
|
.Ar option
|
|
|
|
is the long name of an option, or using the
|
|
|
|
.Cm +- Ns Ar letter
|
|
|
|
syntax, where
|
|
|
|
.Ar letter
|
|
|
|
is the option's single letter name (not all options have a single letter name).
|
|
|
|
The following table lists both option letters (if they exist) and long names
|
|
|
|
along with a description of what the option does:
|
|
|
|
.Bl -tag -width 15n
|
|
|
|
.It Fl A Ar name
|
|
|
|
Sets the elements of the array parameter
|
|
|
|
.Ar name
|
|
|
|
to
|
|
|
|
.Ar arg ...
|
|
|
|
If
|
|
|
|
.Fl A
|
|
|
|
is used, the array is reset (i.e. emptied) first; if
|
|
|
|
.Ic +A
|
|
|
|
is used, the first N elements are set (where N is the number of arguments);
|
|
|
|
the rest are left untouched.
|
|
|
|
.It Fl a \*(Ba Ic allexport
|
|
|
|
All new parameters are created with the export attribute.
|
|
|
|
.It Fl b \*(Ba Ic notify
|
|
|
|
Print job notification messages asynchronously, instead of just before the
|
|
|
|
prompt.
|
|
|
|
Only used if job control is enabled
|
|
|
|
.Pq Fl m .
|
|
|
|
.It Fl C \*(Ba Ic noclobber
|
|
|
|
Prevent \*(Gt redirection from overwriting existing files.
|
|
|
|
Instead, \*(Gt\*(Ba must be used to force an overwrite.
|
|
|
|
.It Fl e \*(Ba Ic errexit
|
|
|
|
Exit (after executing the
|
|
|
|
.Dv ERR
|
|
|
|
trap) as soon as an error occurs or a command fails (i.e. exits with a
|
|
|
|
non-zero status).
|
|
|
|
This does not apply to commands whose exit status is
|
|
|
|
explicitly tested by a shell construct such as
|
|
|
|
.Ic if ,
|
|
|
|
.Ic until ,
|
|
|
|
.Ic while ,
|
|
|
|
.Ic && ,
|
|
|
|
or
|
2006-01-27 11:58:36 +01:00
|
|
|
.Ic \*(Ba\*(Ba
|
2005-05-23 05:06:10 +02:00
|
|
|
statements.
|
|
|
|
.It Fl f \*(Ba Ic noglob
|
|
|
|
Do not expand file name patterns.
|
|
|
|
.It Fl h \*(Ba Ic trackall
|
|
|
|
Create tracked aliases for all executed commands (see
|
|
|
|
.Sx Aliases
|
|
|
|
above).
|
|
|
|
Enabled by default for non-interactive shells.
|
|
|
|
.It Fl k \*(Ba Ic keyword
|
|
|
|
Parameter assignments are recognised anywhere in a command.
|
|
|
|
.It Fl m \*(Ba Ic monitor
|
|
|
|
Enable job control (default for interactive shells).
|
|
|
|
.It Fl n \*(Ba Ic noexec
|
|
|
|
Do not execute any commands.
|
|
|
|
Useful for checking the syntax of scripts
|
|
|
|
(ignored if interactive).
|
|
|
|
.It Fl p \*(Ba Ic privileged
|
|
|
|
The shell is a privileged shell.
|
|
|
|
It is set automatically if, when the shell starts,
|
|
|
|
the real UID or GID does not match
|
|
|
|
the effective UID (EUID) or GID (EGID), respectively.
|
|
|
|
See above for a description of what this means.
|
|
|
|
.It Fl s \*(Ba Ic stdin
|
|
|
|
If used when the shell is invoked, commands are read from standard input.
|
|
|
|
Set automatically if the shell is invoked with no arguments.
|
|
|
|
.Pp
|
|
|
|
When
|
|
|
|
.Fl s
|
|
|
|
is used with the
|
|
|
|
.Ic set
|
|
|
|
command it causes the specified arguments to be sorted before assigning them to
|
|
|
|
the positional parameters (or to array
|
|
|
|
.Ar name ,
|
|
|
|
if
|
|
|
|
.Fl A
|
|
|
|
is used).
|
|
|
|
.It Fl u \*(Ba Ic nounset
|
|
|
|
Referencing of an unset parameter is treated as an error, unless one of the
|
|
|
|
.Ql - ,
|
|
|
|
.Ql + ,
|
|
|
|
or
|
|
|
|
.Ql =
|
|
|
|
modifiers is used.
|
|
|
|
.It Fl v \*(Ba Ic verbose
|
|
|
|
Write shell input to standard error as it is read.
|
|
|
|
.It Fl X \*(Ba Ic markdirs
|
|
|
|
Mark directories with a trailing
|
|
|
|
.Ql /
|
|
|
|
during file name generation.
|
|
|
|
.It Fl x \*(Ba Ic xtrace
|
|
|
|
Print commands and parameter assignments when they are executed, preceded by
|
|
|
|
the value of
|
|
|
|
.Ev PS4 .
|
|
|
|
.It Ic bgnice
|
|
|
|
Background jobs are run with lower priority.
|
|
|
|
.It Ic braceexpand
|
|
|
|
Enable brace expansion (a.k.a. alternation).
|
2005-07-04 14:27:28 +02:00
|
|
|
This is enabled by default.
|
|
|
|
If disabled, tilde expansion after an equals sign is disabled as a side effect.
|
2005-05-23 05:06:10 +02:00
|
|
|
.It Ic emacs
|
|
|
|
Enable BRL emacs-like command-line editing (interactive shells only); see
|
|
|
|
.Sx Emacs editing mode .
|
|
|
|
.It Ic emacs-usemeta
|
|
|
|
In emacs command-line editing, use the 8th bit as meta (^[) prefix.
|
2005-07-04 14:07:41 +02:00
|
|
|
This is disabled by default, so you can use high-bit7 characters in pathnames.
|
2006-02-16 12:48:32 +01:00
|
|
|
If this option is not set, characters in the range 128\-160 are printed as is,
|
|
|
|
which may cause problems in some locales.
|
2005-05-23 05:06:10 +02:00
|
|
|
.It Ic gmacs
|
|
|
|
Enable gmacs-like command-line editing (interactive shells only).
|
2006-08-08 22:07:53 +02:00
|
|
|
Currently identical to emacs editing except that transpose-chars (^T) acts
|
|
|
|
slightly differently.
|
2005-05-23 05:06:10 +02:00
|
|
|
.It Ic ignoreeof
|
|
|
|
The shell will not (easily) exit when end-of-file is read;
|
|
|
|
.Ic exit
|
|
|
|
must be used.
|
|
|
|
To avoid infinite loops, the shell will exit if
|
|
|
|
.Dv EOF
|
|
|
|
is read 13 times in a row.
|
|
|
|
.It Ic interactive
|
|
|
|
The shell is an interactive shell.
|
|
|
|
This option can only be used when the shell is invoked.
|
|
|
|
See above for a description of what this means.
|
|
|
|
.It Ic login
|
|
|
|
The shell is a login shell.
|
|
|
|
This option can only be used when the shell is invoked.
|
|
|
|
See above for a description of what this means.
|
|
|
|
.It Ic nohup
|
|
|
|
Do not kill running jobs with a
|
|
|
|
.Dv SIGHUP
|
|
|
|
signal when a login shell exits.
|
|
|
|
Currently set by default, but this will
|
|
|
|
change in the future to be compatible with the original Korn shell (which
|
|
|
|
doesn't have this option, but does send the
|
|
|
|
.Dv SIGHUP
|
|
|
|
signal).
|
|
|
|
.It Ic nolog
|
|
|
|
No effect.
|
|
|
|
In the original Korn shell, this prevents function definitions from
|
|
|
|
being stored in the history file.
|
|
|
|
.It Ic physical
|
|
|
|
Causes the
|
|
|
|
.Ic cd
|
|
|
|
and
|
|
|
|
.Ic pwd
|
|
|
|
commands to use
|
|
|
|
.Dq physical
|
|
|
|
(i.e. the filesystem's)
|
|
|
|
.Sq ..
|
|
|
|
directories instead of
|
|
|
|
.Dq logical
|
|
|
|
directories (i.e. the shell handles
|
|
|
|
.Sq .. ,
|
|
|
|
which allows the user to be oblivious of symbolic links to directories).
|
|
|
|
Clear by default.
|
|
|
|
Note that setting this option does not affect the current value of the
|
|
|
|
.Ev PWD
|
|
|
|
parameter; only the
|
|
|
|
.Ic cd
|
|
|
|
command changes
|
|
|
|
.Ev PWD .
|
|
|
|
See the
|
|
|
|
.Ic cd
|
|
|
|
and
|
|
|
|
.Ic pwd
|
|
|
|
commands above for more details.
|
2006-08-09 22:44:16 +02:00
|
|
|
.It Ic posix
|
|
|
|
Enable POSIX mode.
|
|
|
|
Currently, this just turns off
|
|
|
|
.Ic braceexpand
|
|
|
|
mode when turned on, which can be turned back on manually.
|
2005-05-23 05:06:10 +02:00
|
|
|
.It Ic restricted
|
|
|
|
The shell is a restricted shell.
|
|
|
|
This option can only be used when the shell is invoked.
|
|
|
|
See above for a description of what this means.
|
2006-08-09 22:44:16 +02:00
|
|
|
.It Ic sh
|
|
|
|
This flag only exists for
|
|
|
|
.Nm pdksh
|
|
|
|
compatibility and cannot be turned on.
|
2005-05-23 05:06:10 +02:00
|
|
|
.It Ic vi
|
|
|
|
Enable
|
|
|
|
.Xr vi 1 Ns -like
|
|
|
|
command-line editing (interactive shells only).
|
|
|
|
.It Ic vi-esccomplete
|
|
|
|
In vi command-line editing, do command and file name completion when escape
|
|
|
|
(^[) is entered in command mode.
|
|
|
|
.It Ic vi-show8
|
|
|
|
Prefix characters with the eighth bit set with
|
|
|
|
.Sq M- .
|
|
|
|
If this option is not set, characters in the range 128\-160 are printed as is,
|
2006-02-16 12:48:32 +01:00
|
|
|
which may cause problems in some locales.
|
2005-05-23 05:06:10 +02:00
|
|
|
.It Ic vi-tabcomplete
|
|
|
|
In vi command-line editing, do command and file name completion when tab (^I)
|
|
|
|
is entered in insert mode.
|
|
|
|
This is the default.
|
|
|
|
.It Ic viraw
|
|
|
|
No effect.
|
|
|
|
In the original Korn shell, unless
|
|
|
|
.Ic viraw
|
|
|
|
was set, the vi command-line mode would let the
|
|
|
|
.Xr tty 4
|
|
|
|
driver do the work until ESC (^[) was entered.
|
2005-05-25 16:15:40 +02:00
|
|
|
.Nm
|
2005-05-23 05:06:10 +02:00
|
|
|
is always in viraw mode.
|
|
|
|
.El
|
|
|
|
.Pp
|
|
|
|
These options can also be used upon invocation of the shell.
|
|
|
|
The current set of
|
|
|
|
options (with single letter names) can be found in the parameter
|
|
|
|
.Sq $- .
|
|
|
|
.Ic set Fl o
|
|
|
|
with no option name will list all the options and whether each is on or off;
|
|
|
|
.Ic set +o
|
|
|
|
will print the long names of all options that are currently on.
|
|
|
|
.Pp
|
|
|
|
Remaining arguments, if any, are positional parameters and are assigned, in
|
|
|
|
order, to the positional parameters (i.e. $1, $2, etc.).
|
|
|
|
If options end with
|
|
|
|
.Ql --
|
|
|
|
and there are no remaining arguments, all positional parameters are cleared.
|
|
|
|
If no options or arguments are given, the values of all names are printed.
|
|
|
|
For unknown historical reasons, a lone
|
|
|
|
.Ql -
|
|
|
|
option is treated specially \- it clears both the
|
|
|
|
.Fl x
|
|
|
|
and
|
|
|
|
.Fl v
|
|
|
|
options.
|
|
|
|
.Pp
|
|
|
|
.It Ic shift Op Ar number
|
|
|
|
The positional parameters
|
|
|
|
.Ar number Ns +1 ,
|
|
|
|
.Ar number Ns +2 ,
|
|
|
|
etc. are renamed to
|
|
|
|
.Sq 1 ,
|
|
|
|
.Sq 2 ,
|
|
|
|
etc.
|
|
|
|
.Ar number
|
|
|
|
defaults to 1.
|
|
|
|
.Pp
|
|
|
|
.It Ic test Ar expression
|
|
|
|
.It Ic \&[ Ar expression Ic \&]
|
|
|
|
.Ic test
|
|
|
|
evaluates the
|
|
|
|
.Ar expression
|
|
|
|
and returns zero status if true, 1 if false, or greater than 1 if there
|
|
|
|
was an error.
|
|
|
|
It is normally used as the condition command of
|
|
|
|
.Ic if
|
|
|
|
and
|
|
|
|
.Ic while
|
|
|
|
statements.
|
|
|
|
Symbolic links are followed for all
|
|
|
|
.Ar file
|
|
|
|
expressions except
|
|
|
|
.Fl h
|
|
|
|
and
|
|
|
|
.Fl L .
|
|
|
|
.Pp
|
|
|
|
The following basic expressions are available:
|
|
|
|
.Bl -tag -width 17n
|
|
|
|
.It Fl a Ar file
|
|
|
|
.Ar file
|
|
|
|
exists.
|
|
|
|
.It Fl b Ar file
|
|
|
|
.Ar file
|
|
|
|
is a block special device.
|
|
|
|
.It Fl c Ar file
|
|
|
|
.Ar file
|
|
|
|
is a character special device.
|
|
|
|
.It Fl d Ar file
|
|
|
|
.Ar file
|
|
|
|
is a directory.
|
|
|
|
.It Fl e Ar file
|
|
|
|
.Ar file
|
|
|
|
exists.
|
|
|
|
.It Fl f Ar file
|
|
|
|
.Ar file
|
|
|
|
is a regular file.
|
|
|
|
.It Fl G Ar file
|
|
|
|
.Ar file Ns 's
|
|
|
|
group is the shell's effective group ID.
|
|
|
|
.It Fl g Ar file
|
|
|
|
.Ar file Ns 's
|
|
|
|
mode has the setgid bit set.
|
|
|
|
.It Fl h Ar file
|
|
|
|
.Ar file
|
|
|
|
is a symbolic link.
|
|
|
|
.It Fl k Ar file
|
|
|
|
.Ar file Ns 's
|
|
|
|
mode has the
|
|
|
|
.Xr sticky 8
|
|
|
|
bit set.
|
|
|
|
.It Fl L Ar file
|
|
|
|
.Ar file
|
|
|
|
is a symbolic link.
|
|
|
|
.It Fl O Ar file
|
|
|
|
.Ar file Ns 's
|
|
|
|
owner is the shell's effective user ID.
|
|
|
|
.It Fl o Ar option
|
|
|
|
Shell
|
|
|
|
.Ar option
|
|
|
|
is set (see the
|
|
|
|
.Ic set
|
|
|
|
command above for a list of options).
|
|
|
|
As a non-standard extension, if the option starts with a
|
|
|
|
.Ql \&! ,
|
|
|
|
the test is negated; the test always fails if
|
|
|
|
.Ar option
|
|
|
|
doesn't exist (so [ -o foo -o -o !foo ] returns true if and only if option
|
|
|
|
.Ar foo
|
|
|
|
exists).
|
|
|
|
.It Fl p Ar file
|
|
|
|
.Ar file
|
|
|
|
is a named pipe.
|
|
|
|
.It Fl r Ar file
|
|
|
|
.Ar file
|
|
|
|
exists and is readable.
|
|
|
|
.It Fl S Ar file
|
|
|
|
.Ar file
|
|
|
|
is a
|
|
|
|
.Xr unix 4 Ns -domain
|
|
|
|
socket.
|
|
|
|
.It Fl s Ar file
|
|
|
|
.Ar file
|
|
|
|
is not empty.
|
|
|
|
.It Fl t Op Ar fd
|
|
|
|
File descriptor
|
|
|
|
.Ar fd
|
|
|
|
is a
|
|
|
|
.Xr tty 4
|
|
|
|
device.
|
|
|
|
.Ar fd
|
2005-10-08 21:34:39 +02:00
|
|
|
may be left out, in which case it is taken to be 1.
|
2005-05-23 05:06:10 +02:00
|
|
|
.It Fl u Ar file
|
|
|
|
.Ar file Ns 's
|
|
|
|
mode has the setuid bit set.
|
|
|
|
.It Fl w Ar file
|
|
|
|
.Ar file
|
|
|
|
exists and is writable.
|
|
|
|
.It Fl x Ar file
|
|
|
|
.Ar file
|
|
|
|
exists and is executable.
|
|
|
|
.It Ar file1 Fl nt Ar file2
|
|
|
|
.Ar file1
|
|
|
|
is newer than
|
|
|
|
.Ar file2
|
|
|
|
or
|
|
|
|
.Ar file1
|
|
|
|
exists and
|
|
|
|
.Ar file2
|
|
|
|
does not.
|
|
|
|
.It Ar file1 Fl ot Ar file2
|
|
|
|
.Ar file1
|
|
|
|
is older than
|
|
|
|
.Ar file2
|
|
|
|
or
|
|
|
|
.Ar file2
|
|
|
|
exists and
|
|
|
|
.Ar file1
|
|
|
|
does not.
|
|
|
|
.It Ar file1 Fl ef Ar file2
|
|
|
|
.Ar file1
|
|
|
|
is the same file as
|
|
|
|
.Ar file2 .
|
|
|
|
.It Ar string
|
|
|
|
.Ar string
|
|
|
|
has non-zero length.
|
|
|
|
.It Fl n Ar string
|
|
|
|
.Ar string
|
|
|
|
is not empty.
|
|
|
|
.It Fl z Ar string
|
|
|
|
.Ar string
|
|
|
|
is empty.
|
|
|
|
.It Ar string No = Ar string
|
|
|
|
Strings are equal.
|
|
|
|
.It Ar string No == Ar string
|
|
|
|
Strings are equal.
|
2005-10-08 21:31:00 +02:00
|
|
|
.It Ar string No \*(Gt Ar string
|
|
|
|
First string operand is greater than second string operand.
|
|
|
|
.It Ar string No \*(Lt Ar string
|
|
|
|
First string operand is less than second string operand.
|
2005-05-23 05:06:10 +02:00
|
|
|
.It Ar string No != Ar string
|
|
|
|
Strings are not equal.
|
|
|
|
.It Ar number Fl eq Ar number
|
|
|
|
Numbers compare equal.
|
|
|
|
.It Ar number Fl ne Ar number
|
|
|
|
Numbers compare not equal.
|
|
|
|
.It Ar number Fl ge Ar number
|
|
|
|
Numbers compare greater than or equal.
|
|
|
|
.It Ar number Fl gt Ar number
|
|
|
|
Numbers compare greater than.
|
|
|
|
.It Ar number Fl le Ar number
|
|
|
|
Numbers compare less than or equal.
|
|
|
|
.It Ar number Fl \< Ar number
|
|
|
|
Numbers compare less than.
|
|
|
|
.El
|
|
|
|
.Pp
|
|
|
|
The above basic expressions, in which unary operators have precedence over
|
|
|
|
binary operators, may be combined with the following operators (listed in
|
|
|
|
increasing order of precedence):
|
|
|
|
.Bd -literal -offset indent
|
|
|
|
expr -o expr Logical OR.
|
|
|
|
expr -a expr Logical AND.
|
|
|
|
! expr Logical NOT.
|
|
|
|
( expr ) Grouping.
|
|
|
|
.Ed
|
|
|
|
.Pp
|
|
|
|
Note that some special rules are applied (courtesy of POSIX)
|
|
|
|
if the number of
|
|
|
|
arguments to
|
|
|
|
.Ic test
|
|
|
|
or
|
|
|
|
.Ic \&[ ... \&]
|
|
|
|
is less than five: if leading
|
|
|
|
.Ql \&!
|
|
|
|
arguments can be stripped such that only one argument remains then a string
|
|
|
|
length test is performed (again, even if the argument is a unary operator); if
|
|
|
|
leading
|
|
|
|
.Ql \&!
|
|
|
|
arguments can be stripped such that three arguments remain and the second
|
|
|
|
argument is a binary operator, then the binary operation is performed (even
|
|
|
|
if the first argument is a unary operator, including an unstripped
|
|
|
|
.Ql \&! ) .
|
|
|
|
.Pp
|
|
|
|
.Sy Note :
|
|
|
|
A common mistake is to use
|
|
|
|
.Dq if \&[ $foo = bar \&]
|
|
|
|
which fails if parameter
|
|
|
|
.Dq foo
|
|
|
|
is
|
|
|
|
.Dv NULL
|
|
|
|
or unset, if it has embedded spaces (i.e.\&
|
|
|
|
.Ev IFS
|
|
|
|
characters), or if it is a unary operator like
|
|
|
|
.Sq \&!
|
|
|
|
or
|
|
|
|
.Sq Fl n .
|
|
|
|
Use tests like
|
2005-05-26 01:31:08 +02:00
|
|
|
.Dq if \&[ x\&"$foo\&" = x"bar" \&]
|
2005-10-08 21:31:00 +02:00
|
|
|
instead, or the double-bracket operator:
|
|
|
|
.Dq if \&[[ $foo = bar \&]]
|
2005-05-23 05:06:10 +02:00
|
|
|
.Pp
|
|
|
|
.It Xo
|
|
|
|
.Ic time
|
|
|
|
.Op Fl p
|
|
|
|
.Op Ar pipeline
|
|
|
|
.Xc
|
|
|
|
If a
|
|
|
|
.Ar pipeline
|
|
|
|
is given, the times used to execute the pipeline are reported.
|
|
|
|
If no pipeline
|
|
|
|
is given, then the user and system time used by the shell itself, and all the
|
|
|
|
commands it has run since it was started, are reported.
|
|
|
|
The times reported are the real time (elapsed time from start to finish),
|
|
|
|
the user CPU time (time spent running in user mode), and the system CPU time
|
|
|
|
(time spent running in kernel mode).
|
|
|
|
Times are reported to standard error; the format of the output is:
|
|
|
|
.Pp
|
|
|
|
.Dl "0m0.00s real 0m0.00s user 0m0.00s system"
|
|
|
|
.Pp
|
|
|
|
If the
|
|
|
|
.Fl p
|
|
|
|
option is given the output is slightly longer:
|
|
|
|
.Bd -literal -offset indent
|
|
|
|
real 0.00
|
|
|
|
user 0.00
|
|
|
|
sys 0.00
|
|
|
|
.Ed
|
|
|
|
.Pp
|
|
|
|
It is an error to specify the
|
|
|
|
.Fl p
|
|
|
|
option unless
|
|
|
|
.Ar pipeline
|
|
|
|
is a simple command.
|
|
|
|
.Pp
|
|
|
|
Simple redirections of standard error do not affect the output of the
|
|
|
|
.Ic time
|
|
|
|
command:
|
|
|
|
.Pp
|
|
|
|
.Dl $ time sleep 1 2\*(Gt afile
|
|
|
|
.Dl $ { time sleep 1; } 2\*(Gt afile
|
|
|
|
.Pp
|
|
|
|
Times for the first command do not go to
|
|
|
|
.Dq afile ,
|
|
|
|
but those of the second command do.
|
|
|
|
.Pp
|
|
|
|
.It Ic times
|
|
|
|
Print the accumulated user and system times used both by the shell
|
|
|
|
and by processes that the shell started which have exited.
|
|
|
|
The format of the output is:
|
|
|
|
.Bd -literal -offset indent
|
|
|
|
0m0.00s 0m0.00s
|
|
|
|
0m0.00s 0m0.00s
|
|
|
|
.Ed
|
|
|
|
.Pp
|
|
|
|
.It Ic trap Op Ar handler signal ...
|
|
|
|
Sets a trap handler that is to be executed when any of the specified signals are
|
|
|
|
received.
|
|
|
|
.Ar handler
|
|
|
|
is either a
|
|
|
|
.Dv NULL
|
|
|
|
string, indicating the signals are to be ignored, a minus sign
|
|
|
|
.Pq Sq - ,
|
|
|
|
indicating that the default action is to be taken for the signals (see
|
|
|
|
.Xr signal 3 ) ,
|
|
|
|
or a string containing shell commands to be evaluated and executed at the first
|
|
|
|
opportunity (i.e. when the current command completes, or before printing the
|
|
|
|
next
|
|
|
|
.Ev PS1
|
|
|
|
prompt) after receipt of one of the signals.
|
|
|
|
.Ar signal
|
|
|
|
is the name of a signal (e.g.\&
|
|
|
|
.Dv PIPE
|
|
|
|
or
|
|
|
|
.Dv ALRM )
|
|
|
|
or the number of the signal (see the
|
|
|
|
.Ic kill -l
|
|
|
|
command above).
|
|
|
|
.Pp
|
|
|
|
There are two special signals:
|
|
|
|
.Dv EXIT
|
2006-01-30 13:37:24 +01:00
|
|
|
(also known as 0) which is executed when the shell is about to exit, and
|
2005-05-23 05:06:10 +02:00
|
|
|
.Dv ERR ,
|
|
|
|
which is executed after an error occurs (an error is something that would cause
|
|
|
|
the shell to exit if the
|
|
|
|
.Fl e
|
|
|
|
or
|
|
|
|
.Ic errexit
|
|
|
|
option were set \- see the
|
|
|
|
.Ic set
|
|
|
|
command above).
|
|
|
|
.Dv EXIT
|
|
|
|
handlers are executed in the environment of the last executed command.
|
|
|
|
Note
|
|
|
|
that for non-interactive shells, the trap handler cannot be changed for signals
|
|
|
|
that were ignored when the shell started.
|
|
|
|
.Pp
|
|
|
|
With no arguments,
|
|
|
|
.Ic trap
|
|
|
|
lists, as a series of
|
|
|
|
.Ic trap
|
|
|
|
commands, the current state of the traps that have been set since the shell
|
|
|
|
started.
|
|
|
|
Note that the output of
|
|
|
|
.Ic trap
|
|
|
|
cannot be usefully piped to another process (an artifact of the fact that
|
|
|
|
traps are cleared when subprocesses are created).
|
|
|
|
.Pp
|
|
|
|
The original Korn shell's
|
|
|
|
.Dv DEBUG
|
|
|
|
trap and the handling of
|
|
|
|
.Dv ERR
|
|
|
|
and
|
|
|
|
.Dv EXIT
|
|
|
|
traps in functions are not yet implemented.
|
|
|
|
.Pp
|
|
|
|
.It Ic true
|
|
|
|
A command that exits with a zero value.
|
|
|
|
.Pp
|
|
|
|
.It Xo
|
|
|
|
.Ic typeset
|
|
|
|
.Oo Op Ic +-lprtUux
|
|
|
|
.Op Fl L Ns Op Ar n
|
|
|
|
.Op Fl R Ns Op Ar n
|
|
|
|
.Op Fl Z Ns Op Ar n
|
|
|
|
.Op Fl i Ns Op Ar n
|
|
|
|
.No \*(Ba Fl f Op Fl tux Oc
|
|
|
|
.Oo Ar name
|
|
|
|
.Op Ns = Ns Ar value
|
|
|
|
.Ar ... Oc
|
|
|
|
.Xc
|
|
|
|
Display or set parameter attributes.
|
|
|
|
With no
|
|
|
|
.Ar name
|
|
|
|
arguments, parameter attributes are displayed; if no options are used, the
|
|
|
|
current attributes of all parameters are printed as
|
|
|
|
.Ic typeset
|
|
|
|
commands; if an option is given (or
|
|
|
|
.Ql -
|
|
|
|
with no option letter), all parameters and their values with the specified
|
|
|
|
attributes are printed; if options are introduced with
|
|
|
|
.Ql + ,
|
|
|
|
parameter values are not printed.
|
|
|
|
.Pp
|
|
|
|
If
|
|
|
|
.Ar name
|
|
|
|
arguments are given, the attributes of the named parameters are set
|
|
|
|
.Pq Ic -
|
|
|
|
or cleared
|
|
|
|
.Pq Ic + .
|
|
|
|
Values for parameters may optionally be specified.
|
|
|
|
If
|
|
|
|
.Ic typeset
|
|
|
|
is used inside a function, any newly created parameters are local to the
|
|
|
|
function.
|
|
|
|
.Pp
|
|
|
|
When
|
|
|
|
.Fl f
|
|
|
|
is used,
|
|
|
|
.Ic typeset
|
|
|
|
operates on the attributes of functions.
|
|
|
|
As with parameters, if no
|
|
|
|
.Ar name
|
|
|
|
arguments are given,
|
|
|
|
functions are listed with their values (i.e. definitions) unless
|
|
|
|
options are introduced with
|
|
|
|
.Ql + ,
|
|
|
|
in which case only the function names are reported.
|
|
|
|
.Bl -tag -width Ds
|
|
|
|
.It Fl f
|
|
|
|
Function mode.
|
|
|
|
Display or set functions and their attributes, instead of parameters.
|
|
|
|
.It Fl i Ns Op Ar n
|
|
|
|
Integer attribute.
|
|
|
|
.Ar n
|
|
|
|
specifies the base to use when displaying the integer (if not specified, the
|
|
|
|
base given in the first assignment is used).
|
|
|
|
Parameters with this attribute may
|
|
|
|
be assigned values containing arithmetic expressions.
|
|
|
|
.It Fl L Ns Op Ar n
|
|
|
|
Left justify attribute.
|
|
|
|
.Ar n
|
|
|
|
specifies the field width.
|
|
|
|
If
|
|
|
|
.Ar n
|
|
|
|
is not specified, the current width of a parameter (or the width of its first
|
|
|
|
assigned value) is used.
|
|
|
|
Leading whitespace (and zeros, if used with the
|
|
|
|
.Fl Z
|
|
|
|
option) is stripped.
|
|
|
|
If necessary, values are either truncated or space padded
|
|
|
|
to fit the field width.
|
|
|
|
.It Fl l
|
|
|
|
Lower case attribute.
|
|
|
|
All upper case characters in values are converted to lower case.
|
|
|
|
(In the original Korn shell, this parameter meant
|
|
|
|
.Dq long integer
|
|
|
|
when used with the
|
|
|
|
.Fl i
|
|
|
|
option.)
|
|
|
|
.It Fl p
|
|
|
|
Print complete
|
|
|
|
.Ic typeset
|
|
|
|
commands that can be used to re-create the attributes (but not the values) of
|
|
|
|
parameters.
|
|
|
|
This is the default action (option exists for ksh93 compatibility).
|
|
|
|
.It Fl R Ns Op Ar n
|
|
|
|
Right justify attribute.
|
|
|
|
.Ar n
|
|
|
|
specifies the field width.
|
|
|
|
If
|
|
|
|
.Ar n
|
|
|
|
is not specified, the current width of a parameter (or the width of its first
|
|
|
|
assigned value) is used.
|
|
|
|
Trailing whitespace is stripped.
|
|
|
|
If necessary, values are either stripped of leading characters or space
|
|
|
|
padded to make them fit the field width.
|
|
|
|
.It Fl r
|
|
|
|
Read-only attribute.
|
|
|
|
Parameters with this attribute may not be assigned to or unset.
|
|
|
|
Once this attribute is set, it cannot be turned off.
|
|
|
|
.It Fl t
|
|
|
|
Tag attribute.
|
|
|
|
Has no meaning to the shell; provided for application use.
|
|
|
|
.Pp
|
|
|
|
For functions,
|
|
|
|
.Fl t
|
|
|
|
is the trace attribute.
|
|
|
|
When functions with the trace attribute are executed, the
|
|
|
|
.Ic xtrace
|
|
|
|
.Pq Fl x
|
|
|
|
shell option is temporarily turned on.
|
|
|
|
.It Fl U
|
|
|
|
Unsigned integer attribute.
|
|
|
|
Integers are printed as unsigned values (only
|
|
|
|
useful when combined with the
|
|
|
|
.Fl i
|
|
|
|
option).
|
|
|
|
This option is not in the original Korn shell.
|
|
|
|
.It Fl u
|
|
|
|
Upper case attribute.
|
|
|
|
All lower case characters in values are converted to upper case.
|
|
|
|
(In the original Korn shell, this parameter meant
|
|
|
|
.Dq unsigned integer
|
|
|
|
when used with the
|
|
|
|
.Fl i
|
2006-01-30 13:37:24 +01:00
|
|
|
option which meant upper case letters would never be used for bases greater
|
2005-05-23 05:06:10 +02:00
|
|
|
than 10.
|
|
|
|
See the
|
|
|
|
.Fl U
|
|
|
|
option.)
|
|
|
|
.Pp
|
|
|
|
For functions,
|
|
|
|
.Fl u
|
|
|
|
is the undefined attribute.
|
|
|
|
See
|
|
|
|
.Sx Functions
|
|
|
|
above for the implications of this.
|
|
|
|
.It Fl x
|
|
|
|
Export attribute.
|
|
|
|
Parameters (or functions) are placed in the environment of
|
|
|
|
any executed commands.
|
|
|
|
Exported functions are not yet implemented.
|
|
|
|
.It Fl Z Ns Op Ar n
|
|
|
|
Zero fill attribute.
|
|
|
|
If not combined with
|
|
|
|
.Fl L ,
|
|
|
|
this is the same as
|
|
|
|
.Fl R ,
|
|
|
|
except zero padding is used instead of space padding.
|
|
|
|
.El
|
|
|
|
.Pp
|
|
|
|
.It Xo
|
|
|
|
.Ic ulimit
|
2005-05-26 01:31:08 +02:00
|
|
|
.Op Fl acdfHLlmnpSsTtvw
|
2005-05-23 05:06:10 +02:00
|
|
|
.Op Ar value
|
|
|
|
.Xc
|
|
|
|
Display or set process limits.
|
|
|
|
If no options are used, the file size limit
|
|
|
|
.Pq Fl f
|
|
|
|
is assumed.
|
|
|
|
.Ar value ,
|
|
|
|
if specified, may be either an arithmetic expression or the word
|
|
|
|
.Dq unlimited .
|
|
|
|
The limits affect the shell and any processes created by the shell after a
|
|
|
|
limit is imposed.
|
|
|
|
Note that some systems may not allow limits to be increased
|
|
|
|
once they are set.
|
|
|
|
Also note that the types of limits available are system
|
|
|
|
dependent \- some systems have only the
|
|
|
|
.Fl f
|
|
|
|
limit.
|
|
|
|
.Bl -tag -width 5n
|
|
|
|
.It Fl a
|
|
|
|
Display all limits; unless
|
|
|
|
.Fl H
|
|
|
|
is used, soft limits are displayed.
|
|
|
|
.It Fl c Ar n
|
|
|
|
Impose a size limit of
|
|
|
|
.Ar n
|
|
|
|
blocks on the size of core dumps.
|
|
|
|
.It Fl d Ar n
|
|
|
|
Impose a size limit of
|
|
|
|
.Ar n
|
|
|
|
kibibytes on the size of the data area.
|
|
|
|
.It Fl f Ar n
|
|
|
|
Impose a size limit of
|
|
|
|
.Ar n
|
|
|
|
blocks on files written by the shell and its child processes (files of any
|
|
|
|
size may be read).
|
|
|
|
.It Fl H
|
|
|
|
Set the hard limit only (the default is to set both hard and soft limits).
|
2005-05-26 01:31:08 +02:00
|
|
|
.It Fl L Ar n
|
|
|
|
Control flocks; documentation is missing.
|
2005-05-23 05:06:10 +02:00
|
|
|
.It Fl l Ar n
|
|
|
|
Impose a limit of
|
|
|
|
.Ar n
|
|
|
|
kibibytes on the amount of locked (wired) physical memory.
|
|
|
|
.It Fl m Ar n
|
|
|
|
Impose a limit of
|
|
|
|
.Ar n
|
|
|
|
kibibytes on the amount of physical memory used.
|
|
|
|
.It Fl n Ar n
|
|
|
|
Impose a limit of
|
|
|
|
.Ar n
|
|
|
|
file descriptors that can be open at once.
|
|
|
|
.It Fl p Ar n
|
|
|
|
Impose a limit of
|
|
|
|
.Ar n
|
|
|
|
processes that can be run by the user at any one time.
|
|
|
|
.It Fl S
|
|
|
|
Set the soft limit only (the default is to set both hard and soft limits).
|
|
|
|
.It Fl s Ar n
|
|
|
|
Impose a size limit of
|
|
|
|
.Ar n
|
|
|
|
kibibytes on the size of the stack area.
|
|
|
|
.It Fl T Ar n
|
|
|
|
Impose a time limit of
|
|
|
|
.Ar n
|
|
|
|
real seconds to be used by each process.
|
|
|
|
.It Fl t Ar n
|
|
|
|
Impose a time limit of
|
|
|
|
.Ar n
|
|
|
|
CPU seconds spent in user mode to be used by each process.
|
|
|
|
.It Fl v Ar n
|
|
|
|
Impose a limit of
|
|
|
|
.Ar n
|
2005-06-08 12:25:40 +02:00
|
|
|
kibibytes on the amount of virtual memory (on some
|
|
|
|
operating systems: total address space) used.
|
2005-05-26 01:31:08 +02:00
|
|
|
.It Fl w Ar n
|
|
|
|
Impose a limit of
|
|
|
|
.Ar n
|
|
|
|
kibibytes on the amount of swap space used.
|
2005-05-23 05:06:10 +02:00
|
|
|
.El
|
|
|
|
.Pp
|
|
|
|
As far as
|
|
|
|
.Ic ulimit
|
|
|
|
is concerned, a block is 512 bytes.
|
|
|
|
.Pp
|
|
|
|
.It Xo
|
|
|
|
.Ic umask
|
|
|
|
.Op Fl S
|
|
|
|
.Op Ar mask
|
|
|
|
.Xc
|
|
|
|
Display or set the file permission creation mask, or umask (see
|
|
|
|
.Xr umask 2 ) .
|
|
|
|
If the
|
|
|
|
.Fl S
|
|
|
|
option is used, the mask displayed or set is symbolic; otherwise, it is an
|
|
|
|
octal number.
|
|
|
|
.Pp
|
|
|
|
Symbolic masks are like those used by
|
|
|
|
.Xr chmod 1 .
|
|
|
|
When used, they describe what permissions may be made available (as opposed to
|
|
|
|
octal masks in which a set bit means the corresponding bit is to be cleared).
|
|
|
|
For example,
|
|
|
|
.Dq ug=rwx,o=
|
|
|
|
sets the mask so files will not be readable, writable, or executable by
|
|
|
|
.Dq others ,
|
|
|
|
and is equivalent (on most systems) to the octal mask
|
|
|
|
.Dq 007 .
|
|
|
|
.Pp
|
|
|
|
.It Xo
|
|
|
|
.Ic unalias
|
|
|
|
.Op Fl adt
|
|
|
|
.Op Ar name ...
|
|
|
|
.Xc
|
|
|
|
The aliases for the given names are removed.
|
|
|
|
If the
|
|
|
|
.Fl a
|
|
|
|
option is used, all aliases are removed.
|
|
|
|
If the
|
|
|
|
.Fl t
|
|
|
|
or
|
|
|
|
.Fl d
|
|
|
|
options are used, the indicated operations are carried out on tracked or
|
|
|
|
directory aliases, respectively.
|
|
|
|
.Pp
|
|
|
|
.It Xo
|
|
|
|
.Ic unset
|
|
|
|
.Op Fl fv
|
|
|
|
.Ar parameter ...
|
|
|
|
.Xc
|
|
|
|
Unset the named parameters
|
|
|
|
.Po
|
|
|
|
.Fl v ,
|
|
|
|
the default
|
|
|
|
.Pc
|
|
|
|
or functions
|
|
|
|
.Pq Fl f .
|
|
|
|
The exit status is non-zero if any of the parameters were already unset, zero
|
|
|
|
otherwise.
|
|
|
|
.Pp
|
|
|
|
.It Ic wait Op Ar job ...
|
|
|
|
Wait for the specified job(s) to finish.
|
|
|
|
The exit status of
|
|
|
|
.Ic wait
|
|
|
|
is that of the last specified job; if the last job is killed by a signal, the
|
|
|
|
exit status is 128 + the number of the signal (see
|
|
|
|
.Ic kill -l Ar exit-status
|
|
|
|
above); if the last specified job can't be found (because it never existed, or
|
|
|
|
had already finished), the exit status of
|
|
|
|
.Ic wait
|
|
|
|
is 127.
|
|
|
|
See
|
|
|
|
.Sx Job control
|
|
|
|
below for the format of
|
|
|
|
.Ar job .
|
|
|
|
.Ic wait
|
|
|
|
will return if a signal for which a trap has been set is received, or if a
|
|
|
|
.Dv SIGHUP ,
|
|
|
|
.Dv SIGINT ,
|
|
|
|
or
|
|
|
|
.Dv SIGQUIT
|
|
|
|
signal is received.
|
|
|
|
.Pp
|
|
|
|
If no jobs are specified,
|
|
|
|
.Ic wait
|
|
|
|
waits for all currently running jobs (if any) to finish and exits with a zero
|
|
|
|
status.
|
|
|
|
If job monitoring is enabled, the completion status of jobs is printed
|
|
|
|
(this is not the case when jobs are explicitly specified).
|
|
|
|
.Pp
|
|
|
|
.It Xo
|
|
|
|
.Ic whence
|
|
|
|
.Op Fl pv
|
|
|
|
.Op Ar name ...
|
|
|
|
.Xc
|
|
|
|
For each
|
|
|
|
.Ar name ,
|
|
|
|
the type of command is listed (reserved word, built-in, alias,
|
|
|
|
function, tracked alias, or executable).
|
|
|
|
If the
|
|
|
|
.Fl p
|
|
|
|
option is used, a path search is performed even if
|
|
|
|
.Ar name
|
|
|
|
is a reserved word, alias, etc.
|
|
|
|
Without the
|
|
|
|
.Fl v
|
|
|
|
option,
|
|
|
|
.Ic whence
|
|
|
|
is similar to
|
|
|
|
.Ic command Fl v
|
|
|
|
except that
|
|
|
|
.Ic whence
|
|
|
|
will find reserved words and won't print aliases as alias commands.
|
|
|
|
With the
|
|
|
|
.Fl v
|
|
|
|
option,
|
|
|
|
.Ic whence
|
|
|
|
is the same as
|
|
|
|
.Ic command Fl V .
|
|
|
|
Note that for
|
|
|
|
.Ic whence ,
|
|
|
|
the
|
|
|
|
.Fl p
|
|
|
|
option does not affect the search path used, as it does for
|
|
|
|
.Ic command .
|
|
|
|
If the type of one or more of the names could not be determined, the exit
|
|
|
|
status is non-zero.
|
|
|
|
.El
|
|
|
|
.Ss Job control
|
2006-01-30 13:37:24 +01:00
|
|
|
Job control refers to the shell's ability to monitor and control jobs which
|
2005-05-23 05:06:10 +02:00
|
|
|
are processes or groups of processes created for commands or pipelines.
|
|
|
|
At a minimum, the shell keeps track of the status of the background (i.e.\&
|
|
|
|
asynchronous) jobs that currently exist; this information can be displayed
|
|
|
|
using the
|
|
|
|
.Ic jobs
|
|
|
|
commands.
|
|
|
|
If job control is fully enabled (using
|
|
|
|
.Ic set -m
|
|
|
|
or
|
|
|
|
.Ic set -o monitor ) ,
|
|
|
|
as it is for interactive shells, the processes of a job are placed in their
|
|
|
|
own process group.
|
|
|
|
Foreground jobs can be stopped by typing the suspend
|
|
|
|
character from the terminal (normally ^Z), jobs can be restarted in either the
|
|
|
|
foreground or background using the
|
|
|
|
.Ic fg
|
|
|
|
and
|
|
|
|
.Ic bg
|
|
|
|
commands, and the state of the terminal is saved or restored when a foreground
|
|
|
|
job is stopped or restarted, respectively.
|
|
|
|
.Pp
|
|
|
|
Note that only commands that create processes (e.g. asynchronous commands,
|
|
|
|
subshell commands, and non-built-in, non-function commands) can be stopped;
|
|
|
|
commands like
|
|
|
|
.Ic read
|
|
|
|
cannot be.
|
|
|
|
.Pp
|
|
|
|
When a job is created, it is assigned a job number.
|
|
|
|
For interactive shells, this number is printed inside
|
|
|
|
.Dq [..] ,
|
|
|
|
followed by the process IDs of the processes in the job when an asynchronous
|
|
|
|
command is run.
|
|
|
|
A job may be referred to in the
|
|
|
|
.Ic bg ,
|
|
|
|
.Ic fg ,
|
|
|
|
.Ic jobs ,
|
|
|
|
.Ic kill ,
|
|
|
|
and
|
|
|
|
.Ic wait
|
|
|
|
commands either by the process ID of the last process in the command pipeline
|
|
|
|
(as stored in the
|
|
|
|
.Ic $!\&
|
|
|
|
parameter) or by prefixing the job number with a percent
|
|
|
|
sign
|
|
|
|
.Pq Sq % .
|
|
|
|
Other percent sequences can also be used to refer to jobs:
|
|
|
|
.Bl -tag -width "%+ | %% | %XX"
|
|
|
|
.It %+ \*(Ba %% \*(Ba %
|
|
|
|
The most recently stopped job, or, if there are no stopped jobs, the oldest
|
|
|
|
running job.
|
|
|
|
.It %-
|
|
|
|
The job that would be the
|
|
|
|
.Ic %+
|
|
|
|
job if the latter did not exist.
|
|
|
|
.It % Ns Ar n
|
|
|
|
The job with job number
|
|
|
|
.Ar n .
|
|
|
|
.It %? Ns Ar string
|
|
|
|
The job with its command containing the string
|
|
|
|
.Ar string
|
|
|
|
(an error occurs if multiple jobs are matched).
|
|
|
|
.It % Ns Ar string
|
|
|
|
The job with its command starting with the string
|
|
|
|
.Ar string
|
|
|
|
(an error occurs if multiple jobs are matched).
|
|
|
|
.El
|
|
|
|
.Pp
|
|
|
|
When a job changes state (e.g. a background job finishes or foreground job is
|
|
|
|
stopped), the shell prints the following status information:
|
|
|
|
.Pp
|
|
|
|
.D1 [ Ns Ar number ] Ar flag status command
|
|
|
|
.Pp
|
|
|
|
where...
|
|
|
|
.Bl -tag -width "command"
|
|
|
|
.It Ar number
|
|
|
|
is the job number of the job;
|
|
|
|
.It Ar flag
|
|
|
|
is the
|
|
|
|
.Ql +
|
|
|
|
or
|
|
|
|
.Ql -
|
|
|
|
character if the job is the
|
|
|
|
.Ic %+
|
|
|
|
or
|
|
|
|
.Ic %-
|
|
|
|
job, respectively, or space if it is neither;
|
|
|
|
.It Ar status
|
|
|
|
indicates the current state of the job and can be:
|
|
|
|
.Bl -tag -width "RunningXX"
|
|
|
|
.It Done Op Ar number
|
|
|
|
The job exited.
|
|
|
|
.Ar number
|
2006-01-30 13:37:24 +01:00
|
|
|
is the exit status of the job which is omitted if the status is zero.
|
2005-05-23 05:06:10 +02:00
|
|
|
.It Running
|
|
|
|
The job has neither stopped nor exited (note that running does not necessarily
|
|
|
|
mean consuming CPU time \-
|
|
|
|
the process could be blocked waiting for some event).
|
|
|
|
.It Stopped Op Ar signal
|
|
|
|
The job was stopped by the indicated
|
|
|
|
.Ar signal
|
|
|
|
(if no signal is given, the job was stopped by
|
|
|
|
.Dv SIGTSTP ) .
|
|
|
|
.It Ar signal-description Op Dq core dumped
|
|
|
|
The job was killed by a signal (e.g. memory fault, hangup); use
|
|
|
|
.Ic kill -l
|
|
|
|
for a list of signal descriptions.
|
|
|
|
The
|
|
|
|
.Dq core dumped
|
|
|
|
message indicates the process created a core file.
|
|
|
|
.El
|
|
|
|
.It Ar command
|
|
|
|
is the command that created the process.
|
|
|
|
If there are multiple processes in
|
|
|
|
the job, each process will have a line showing its
|
|
|
|
.Ar command
|
|
|
|
and possibly its
|
|
|
|
.Ar status ,
|
|
|
|
if it is different from the status of the previous process.
|
|
|
|
.El
|
|
|
|
.Pp
|
|
|
|
When an attempt is made to exit the shell while there are jobs in the stopped
|
|
|
|
state, the shell warns the user that there are stopped jobs and does not exit.
|
|
|
|
If another attempt is immediately made to exit the shell, the stopped jobs are
|
|
|
|
sent a
|
|
|
|
.Dv SIGHUP
|
|
|
|
signal and the shell exits.
|
|
|
|
Similarly, if the
|
|
|
|
.Ic nohup
|
|
|
|
option is not set and there are running jobs when an attempt is made to exit
|
|
|
|
a login shell, the shell warns the user and does not exit.
|
|
|
|
If another attempt
|
|
|
|
is immediately made to exit the shell, the running jobs are sent a
|
|
|
|
.Dv SIGHUP
|
|
|
|
signal and the shell exits.
|
|
|
|
.Ss Interactive input line editing
|
|
|
|
The shell supports three modes of reading command lines from a
|
|
|
|
.Xr tty 4
|
|
|
|
in an interactive session, controlled by the
|
|
|
|
.Ic emacs ,
|
|
|
|
.Ic gmacs ,
|
|
|
|
and
|
|
|
|
.Ic vi
|
|
|
|
options (at most one of these can be set at once).
|
|
|
|
The default is
|
|
|
|
.Ic emacs .
|
|
|
|
Editing modes can be set explicitly using the
|
|
|
|
.Ic set
|
2005-07-04 14:07:41 +02:00
|
|
|
built-in.
|
2005-05-23 05:06:10 +02:00
|
|
|
If none of these options are enabled,
|
|
|
|
the shell simply reads lines using the normal
|
|
|
|
.Xr tty 4
|
|
|
|
driver.
|
|
|
|
If the
|
|
|
|
.Ic emacs
|
|
|
|
or
|
|
|
|
.Ic gmacs
|
|
|
|
option is set, the shell allows emacs-like editing of the command; similarly,
|
|
|
|
if the
|
|
|
|
.Ic vi
|
|
|
|
option is set, the shell allows vi-like editing of the command.
|
|
|
|
These modes are described in detail in the following sections.
|
|
|
|
.Pp
|
|
|
|
In these editing modes, if a line is longer than the screen width (see the
|
|
|
|
.Ev COLUMNS
|
|
|
|
parameter),
|
|
|
|
a
|
|
|
|
.Ql \*(Gt ,
|
|
|
|
.Ql + ,
|
|
|
|
or
|
|
|
|
.Ql \*(Lt
|
|
|
|
character is displayed in the last column indicating that there are more
|
|
|
|
characters after, before and after, or before the current position,
|
|
|
|
respectively.
|
|
|
|
The line is scrolled horizontally as necessary.
|
|
|
|
.Ss Emacs editing mode
|
|
|
|
When the
|
|
|
|
.Ic emacs
|
|
|
|
option is set, interactive input line editing is enabled.
|
|
|
|
Warning: This mode is
|
|
|
|
slightly different from the emacs mode in the original Korn shell.
|
|
|
|
In this mode, various editing commands
|
|
|
|
(typically bound to one or more control characters) cause immediate actions
|
|
|
|
without waiting for a newline.
|
|
|
|
Several editing commands are bound to particular
|
|
|
|
control characters when the shell is invoked; these bindings can be changed
|
|
|
|
using the
|
|
|
|
.Ic bind
|
|
|
|
command.
|
|
|
|
.Pp
|
|
|
|
The following is a list of available editing commands.
|
|
|
|
Each description starts with the name of the command,
|
|
|
|
suffixed with a colon;
|
|
|
|
an
|
|
|
|
.Op Ar n
|
|
|
|
(if the command can be prefixed with a count); and any keys the command is
|
|
|
|
bound to by default, written using caret notation
|
|
|
|
e.g. the ASCII ESC character is written as ^[.
|
2005-05-26 01:31:08 +02:00
|
|
|
These control sequences are not case sensitive.
|
2005-05-23 05:06:10 +02:00
|
|
|
A count prefix for a command is entered using the sequence
|
|
|
|
.Pf ^[ Ns Ar n ,
|
|
|
|
where
|
|
|
|
.Ar n
|
|
|
|
is a sequence of 1 or more digits.
|
|
|
|
Unless otherwise specified, if a count is
|
|
|
|
omitted, it defaults to 1.
|
|
|
|
.Pp
|
|
|
|
Note that editing command names are used only with the
|
|
|
|
.Ic bind
|
|
|
|
command.
|
|
|
|
Furthermore, many editing commands are useful only on terminals with
|
|
|
|
a visible cursor.
|
|
|
|
The default bindings were chosen to resemble corresponding
|
|
|
|
Emacs key bindings.
|
|
|
|
The user's
|
|
|
|
.Xr tty 4
|
|
|
|
characters (e.g.\&
|
|
|
|
.Dv ERASE )
|
|
|
|
are bound to
|
|
|
|
reasonable substitutes and override the default bindings.
|
|
|
|
.Bl -tag -width Ds
|
|
|
|
.It abort: ^C, ^G
|
2006-08-08 22:19:14 +02:00
|
|
|
Abort the current command, empty the line buffer and
|
|
|
|
set the exit state to interrupted.
|
2005-05-23 05:06:10 +02:00
|
|
|
.It auto-insert: Op Ar n
|
|
|
|
Simply causes the character to appear as literal input.
|
|
|
|
Most ordinary characters are bound to this.
|
|
|
|
.It Xo backward-char:
|
|
|
|
.Op Ar n
|
|
|
|
.No ^B , ^XD
|
|
|
|
.Xc
|
|
|
|
Moves the cursor backward
|
|
|
|
.Ar n
|
|
|
|
characters.
|
|
|
|
.It Xo backward-word:
|
|
|
|
.Op Ar n
|
|
|
|
.No ^[b
|
|
|
|
.Xc
|
|
|
|
Moves the cursor backward to the beginning of the word; words consist of
|
|
|
|
alphanumerics, underscore
|
|
|
|
.Pq Sq _ ,
|
|
|
|
and dollar sign
|
|
|
|
.Pq Sq $
|
|
|
|
characters.
|
|
|
|
.It beginning-of-history: ^[\*(Lt
|
|
|
|
Moves to the beginning of the history.
|
|
|
|
.It beginning-of-line: ^A
|
|
|
|
Moves the cursor to the beginning of the edited input line.
|
|
|
|
.It Xo capitalise-word:
|
|
|
|
.Op Ar n
|
|
|
|
.No ^[C , ^[c
|
|
|
|
.Xc
|
|
|
|
Uppercase the first character in the next
|
|
|
|
.Ar n
|
|
|
|
words, leaving the cursor past the end of the last word.
|
|
|
|
.It comment: ^[#
|
|
|
|
If the current line does not begin with a comment character, one is added at
|
|
|
|
the beginning of the line and the line is entered (as if return had been
|
|
|
|
pressed); otherwise, the existing comment characters are removed and the cursor
|
|
|
|
is placed at the beginning of the line.
|
|
|
|
.It complete: ^[^[
|
|
|
|
Automatically completes as much as is unique of the command name or the file
|
|
|
|
name containing the cursor.
|
|
|
|
If the entire remaining command or file name is
|
|
|
|
unique, a space is printed after its completion, unless it is a directory name
|
|
|
|
in which case
|
|
|
|
.Ql /
|
|
|
|
is appended.
|
|
|
|
If there is no command or file name with the current partial word
|
|
|
|
as its prefix, a bell character is output (usually causing a beep to be
|
|
|
|
sounded).
|
|
|
|
.It complete-command: ^X^[
|
|
|
|
Automatically completes as much as is unique of the command name having the
|
|
|
|
partial word up to the cursor as its prefix, as in the
|
|
|
|
.Ic complete
|
|
|
|
command above.
|
|
|
|
.It complete-file: ^[^X
|
|
|
|
Automatically completes as much as is unique of the file name having the
|
|
|
|
partial word up to the cursor as its prefix, as in the
|
|
|
|
.Ic complete
|
|
|
|
command described above.
|
|
|
|
.It complete-list: ^I, ^[=
|
|
|
|
Complete as much as is possible of the current word,
|
|
|
|
and list the possible completions for it.
|
|
|
|
If only one completion is possible,
|
|
|
|
match as in the
|
|
|
|
.Ic complete
|
|
|
|
command above.
|
2005-05-26 01:31:08 +02:00
|
|
|
Note that ^I is usually generated by the TAB (tabulator) key.
|
2005-05-23 05:06:10 +02:00
|
|
|
.It Xo delete-char-backward:
|
|
|
|
.Op Ar n
|
|
|
|
.No ERASE , ^? , ^H
|
|
|
|
.Xc
|
|
|
|
Deletes
|
|
|
|
.Ar n
|
|
|
|
characters before the cursor.
|
|
|
|
.It delete-char-forward: Op Ar n
|
|
|
|
Deletes
|
|
|
|
.Ar n
|
|
|
|
characters after the cursor.
|
|
|
|
.It Xo delete-word-backward:
|
|
|
|
.Op Ar n
|
|
|
|
.No ERASE , ^[^? , ^[^H , ^[h
|
|
|
|
.Xc
|
|
|
|
Deletes
|
|
|
|
.Ar n
|
|
|
|
words before the cursor.
|
|
|
|
.It Xo delete-word-forward:
|
|
|
|
.Op Ar n
|
|
|
|
.No ^[d
|
|
|
|
.Xc
|
|
|
|
Deletes characters after the cursor up to the end of
|
|
|
|
.Ar n
|
|
|
|
words.
|
|
|
|
.It Xo down-history:
|
|
|
|
.Op Ar n
|
|
|
|
.No ^N , ^XB
|
|
|
|
.Xc
|
|
|
|
Scrolls the history buffer forward
|
|
|
|
.Ar n
|
|
|
|
lines (later).
|
|
|
|
Each input line originally starts just after the last entry
|
|
|
|
in the history buffer, so
|
|
|
|
.Ic down-history
|
|
|
|
is not useful until either
|
|
|
|
.Ic search-history
|
|
|
|
or
|
|
|
|
.Ic up-history
|
|
|
|
has been performed.
|
|
|
|
.It Xo downcase-word:
|
|
|
|
.Op Ar n
|
|
|
|
.No ^[L , ^[l
|
|
|
|
.Xc
|
|
|
|
Lowercases the next
|
|
|
|
.Ar n
|
|
|
|
words.
|
|
|
|
.It end-of-history: ^[\*(Gt
|
|
|
|
Moves to the end of the history.
|
|
|
|
.It end-of-line: ^E
|
|
|
|
Moves the cursor to the end of the input line.
|
|
|
|
.It eot: ^_
|
|
|
|
Acts as an end-of-file; this is useful because edit-mode input disables
|
|
|
|
normal terminal input canonicalization.
|
|
|
|
.It Xo eot-or-delete:
|
|
|
|
.Op Ar n
|
|
|
|
.No ^D
|
|
|
|
.Xc
|
|
|
|
Acts as
|
|
|
|
.Ic eot
|
|
|
|
if alone on a line; otherwise acts as
|
|
|
|
.Ic delete-char-forward .
|
|
|
|
.It error:
|
|
|
|
Error (ring the bell).
|
|
|
|
.It exchange-point-and-mark: ^X^X
|
|
|
|
Places the cursor where the mark is and sets the mark to where the cursor was.
|
|
|
|
.It expand-file: ^[*
|
|
|
|
Appends a
|
|
|
|
.Ql *
|
|
|
|
to the current word and replaces the word with the result of performing file
|
|
|
|
globbing on the word.
|
|
|
|
If no files match the pattern, the bell is rung.
|
|
|
|
.It Xo forward-char:
|
|
|
|
.Op Ar n
|
|
|
|
.No ^F , ^XC
|
|
|
|
.Xc
|
|
|
|
Moves the cursor forward
|
|
|
|
.Ar n
|
|
|
|
characters.
|
|
|
|
.It Xo forward-word:
|
|
|
|
.Op Ar n
|
|
|
|
.No ^[f
|
|
|
|
.Xc
|
|
|
|
Moves the cursor forward to the end of the
|
|
|
|
.Ar n Ns th
|
|
|
|
word.
|
|
|
|
.It Xo goto-history:
|
|
|
|
.Op Ar n
|
|
|
|
.No ^[g
|
|
|
|
.Xc
|
|
|
|
Goes to history number
|
|
|
|
.Ar n .
|
|
|
|
.It kill-line: KILL
|
|
|
|
Deletes the entire input line.
|
|
|
|
.It kill-region: ^W
|
|
|
|
Deletes the input between the cursor and the mark.
|
|
|
|
.It Xo kill-to-eol:
|
|
|
|
.Op Ar n
|
|
|
|
.No ^K
|
|
|
|
.Xc
|
|
|
|
Deletes the input from the cursor to the end of the line if
|
|
|
|
.Ar n
|
|
|
|
is not specified; otherwise deletes characters between the cursor and column
|
|
|
|
.Ar n .
|
|
|
|
.It list: ^[?
|
|
|
|
Prints a sorted, columnated list of command names or file names (if any) that
|
|
|
|
can complete the partial word containing the cursor.
|
|
|
|
Directory names have
|
|
|
|
.Ql /
|
|
|
|
appended to them.
|
|
|
|
.It list-command: ^X?
|
|
|
|
Prints a sorted, columnated list of command names (if any) that can complete
|
|
|
|
the partial word containing the cursor.
|
|
|
|
.It list-file: ^X^Y
|
|
|
|
Prints a sorted, columnated list of file names (if any) that can complete the
|
|
|
|
partial word containing the cursor.
|
|
|
|
File type indicators are appended as described under
|
|
|
|
.Ic list
|
|
|
|
above.
|
|
|
|
.It newline: ^J , ^M
|
|
|
|
Causes the current input line to be processed by the shell.
|
|
|
|
The current cursor position may be anywhere on the line.
|
|
|
|
.It newline-and-next: ^O
|
|
|
|
Causes the current input line to be processed by the shell, and the next line
|
|
|
|
from history becomes the current line.
|
|
|
|
This is only useful after an
|
|
|
|
.Ic up-history
|
|
|
|
or
|
|
|
|
.Ic search-history .
|
|
|
|
.It no-op: QUIT
|
|
|
|
This does nothing.
|
|
|
|
.It prefix-1: ^[
|
|
|
|
Introduces a 2-character command sequence.
|
|
|
|
.It prefix-2: ^X , ^[[ , ^[O
|
|
|
|
Introduces a 2-character command sequence.
|
|
|
|
.It Xo prev-hist-word:
|
|
|
|
.Op Ar n
|
|
|
|
.No ^[. , ^[_
|
|
|
|
.Xc
|
|
|
|
The last
|
|
|
|
.Pq Ar n Ns th
|
|
|
|
word of the previous command is inserted at the cursor.
|
2006-08-01 14:44:17 +02:00
|
|
|
.It quote: ^^ , ^V
|
2005-05-23 05:06:10 +02:00
|
|
|
The following character is taken literally rather than as an editing command.
|
|
|
|
.It redraw: ^L
|
2006-08-02 13:50:30 +02:00
|
|
|
Reprints the last line of the prompt string and the current input line.
|
2005-05-23 05:06:10 +02:00
|
|
|
.It Xo search-character-backward:
|
|
|
|
.Op Ar n
|
|
|
|
.No ^[^]
|
|
|
|
.Xc
|
|
|
|
Search backward in the current line for the
|
|
|
|
.Ar n Ns th
|
|
|
|
occurrence of the next character typed.
|
|
|
|
.It Xo search-character-forward:
|
|
|
|
.Op Ar n
|
|
|
|
.No ^]
|
|
|
|
.Xc
|
|
|
|
Search forward in the current line for the
|
|
|
|
.Ar n Ns th
|
|
|
|
occurrence of the next character typed.
|
|
|
|
.It search-history: ^R
|
|
|
|
Enter incremental search mode.
|
|
|
|
The internal history list is searched
|
|
|
|
backwards for commands matching the input.
|
|
|
|
An initial
|
|
|
|
.Ql ^
|
|
|
|
in the search string anchors the search.
|
2006-08-08 22:19:14 +02:00
|
|
|
The escape key will leave search mode.
|
2005-05-23 05:06:10 +02:00
|
|
|
Other commands will be executed after leaving search mode.
|
|
|
|
Successive
|
|
|
|
.Ic search-history
|
|
|
|
commands continue searching backward to the next previous occurrence of the
|
|
|
|
pattern.
|
|
|
|
The history buffer retains only a finite number of lines; the oldest
|
|
|
|
are discarded as necessary.
|
|
|
|
.It set-mark-command: ^[ Ns Aq space
|
|
|
|
Set the mark at the cursor position.
|
|
|
|
.It transpose-chars: ^T
|
|
|
|
If at the end of line, or if the
|
|
|
|
.Ic gmacs
|
|
|
|
option is set, this exchanges the two previous characters; otherwise, it
|
|
|
|
exchanges the previous and current characters and moves the cursor one
|
|
|
|
character to the right.
|
|
|
|
.It Xo up-history:
|
|
|
|
.Op Ar n
|
|
|
|
.No ^P , ^XA
|
|
|
|
.Xc
|
|
|
|
Scrolls the history buffer backward
|
|
|
|
.Ar n
|
|
|
|
lines (earlier).
|
|
|
|
.It Xo upcase-word:
|
|
|
|
.Op Ar n
|
|
|
|
.No ^[U , ^[u
|
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.Xc
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Uppercase the next
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.Ar n
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words.
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2006-08-01 14:44:17 +02:00
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.It version: ^[^V
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Display the version of
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.Nm .
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The current edit buffer is restored as soon as a key is pressed.
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The restoring keypress is processed, unless it is a space.
|
2005-05-23 05:06:10 +02:00
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.It yank: ^Y
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Inserts the most recently killed text string at the current cursor position.
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.It yank-pop: ^[y
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Immediately after a
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.Ic yank ,
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replaces the inserted text string with the next previously killed text string.
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.El
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.Ss Vi editing mode
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The vi command-line editor in
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.Nm
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has basically the same commands as the
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.Xr vi 1
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editor with the following exceptions:
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.Bl -bullet
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.It
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You start out in insert mode.
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.It
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There are file name and command completion commands:
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=, \e, *, ^X, ^E, ^F, and, optionally,
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.Aq tab
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and
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.Aq esc .
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.It
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The
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.Ic _
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command is different (in
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.Nm
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it is the last argument command; in
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.Xr vi 1
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it goes to the start of the current line).
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.It
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The
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.Ic /
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and
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.Ic G
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commands move in the opposite direction to the
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.Ic j
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command.
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.It
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Commands which don't make sense in a single line editor are not available
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(e.g. screen movement commands and
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.Xr ex 1 Ns -style
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colon
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.Pq Ic \&:
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commands).
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.El
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.Pp
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Like
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.Xr vi 1 ,
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there are two modes:
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.Dq insert
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mode and
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.Dq command
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mode.
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In insert mode, most characters are simply put in the buffer at the
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current cursor position as they are typed; however, some characters are
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treated specially.
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In particular, the following characters are taken from current
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.Xr tty 4
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settings
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(see
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.Xr stty 1 )
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and have their usual meaning (normal values are in parentheses): kill (^U),
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erase (^?), werase (^W), eof (^D), intr (^C), and quit (^\e).
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In addition to
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the above, the following characters are also treated specially in insert mode:
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.Bl -tag -width 10n
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.It ^E
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Command and file name enumeration (see below).
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.It ^F
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Command and file name completion (see below).
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If used twice in a row, the
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list of possible completions is displayed; if used a third time, the completion
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is undone.
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.It ^H
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Erases previous character.
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.It ^J \*(Ba ^M
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End of line.
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The current line is read, parsed, and executed by the shell.
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.It ^V
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Literal next.
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The next character typed is not treated specially (can be used
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to insert the characters being described here).
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.It ^X
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Command and file name expansion (see below).
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.It Aq esc
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Puts the editor in command mode (see below).
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.It Aq tab
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Optional file name and command completion (see
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.Ic ^F
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above), enabled with
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.Ic set -o vi-tabcomplete .
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.El
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.Pp
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In command mode, each character is interpreted as a command.
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Characters that
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don't correspond to commands, are illegal combinations of commands, or are
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commands that can't be carried out, all cause beeps.
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In the following command descriptions, an
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.Op Ar n
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indicates the command may be prefixed by a number (e.g.\&
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.Ic 10l
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moves right 10 characters); if no number prefix is used,
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.Ar n
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is assumed to be 1 unless otherwise specified.
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The term
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.Dq current position
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refers to the position between the cursor and the character preceding the
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cursor.
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A
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.Dq word
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is a sequence of letters, digits, and underscore characters or a sequence of
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non-letter, non-digit, non-underscore, and non-whitespace characters (e.g.\&
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.Dq ab2*&^
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contains two words) and a
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.Dq big-word
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is a sequence of non-whitespace characters.
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.Pp
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Special
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.Nm
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vi commands:
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.Pp
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The following commands are not in, or are different from, the normal vi file
|
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editor:
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.Bl -tag -width 10n
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.It Xo
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.Oo Ar n Oc Ns _
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.Xc
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Insert a space followed by the
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.Ar n Ns th
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big-word from the last command in the history at the current position and enter
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insert mode; if
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.Ar n
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is not specified, the last word is inserted.
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.It #
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Insert the comment character
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.Pq Sq #
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at the start of the current line and return the line to the shell (equivalent
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to
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.Ic I#^J ) .
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.It Xo
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.Oo Ar n Oc Ns g
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.Xc
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Like
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.Ic G ,
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except if
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.Ar n
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is not specified, it goes to the most recent remembered line.
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.It Xo
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.Oo Ar n Oc Ns v
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.Xc
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Edit line
|
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.Ar n
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using the
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.Xr vi 1
|
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|
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editor; if
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.Ar n
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is not specified, the current line is edited.
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The actual command executed is
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|
.Ic fc -e ${VISUAL:-${EDITOR:-vi}} Ar n .
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.It * and ^X
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Command or file name expansion is applied to the current big-word (with an
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appended
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.Ql *
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if the word contains no file globbing characters) \- the big-word is replaced
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with the resulting words.
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|
If the current big-word is the first on the line (or
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|
follows one of the following characters:
|
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|
.Ql \&; ,
|
2006-01-27 11:58:36 +01:00
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.Ql \*(Ba ,
|
2005-05-23 05:06:10 +02:00
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.Ql & ,
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.Ql ( ,
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or
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|
.Ql \&)
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|
and does not contain a slash
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|
.Pq Sq /
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then command expansion is done; otherwise file name expansion is done.
|
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|
Command expansion will match the big-word against all aliases, functions, and
|
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|
|
built-in commands as well as any executable files found by searching the
|
|
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|
directories in the
|
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|
.Ev PATH
|
|
|
|
parameter.
|
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|
File name expansion matches the big-word against the files in the
|
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current directory.
|
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|
After expansion, the cursor is placed just past the last
|
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word and the editor is in insert mode.
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.It Xo
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.Oo Ar n Oc Ns \e ,
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.Oo Ar n Oc Ns ^F ,
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.Oo Ar n Oc Ns Aq tab ,
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.No and
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.Oo Ar n Oc Ns Aq esc
|
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.Xc
|
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|
Command/file name completion.
|
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|
|
Replace the current big-word with the
|
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|
|
longest unique match obtained after performing command and file name expansion.
|
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|
.Aq tab
|
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|
is only recognised if the
|
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|
.Ic vi-tabcomplete
|
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|
|
option is set, while
|
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|
.Aq esc
|
|
|
|
is only recognised if the
|
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|
|
.Ic vi-esccomplete
|
|
|
|
option is set (see
|
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|
.Ic set -o ) .
|
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|
If
|
|
|
|
.Ar n
|
|
|
|
is specified, the
|
|
|
|
.Ar n Ns th
|
|
|
|
possible completion is selected (as reported by the command/file name
|
|
|
|
enumeration command).
|
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|
.It = and ^E
|
|
|
|
Command/file name enumeration.
|
|
|
|
List all the commands or files that match the current big-word.
|
2006-08-01 14:44:17 +02:00
|
|
|
.It ^V
|
|
|
|
Display the version of
|
|
|
|
.Nm .
|
|
|
|
The current edit buffer is restored as soon as a key is pressed.
|
|
|
|
The restoring keypress is ignored.
|
2005-05-23 05:06:10 +02:00
|
|
|
.It @ Ns Ar c
|
|
|
|
Macro expansion.
|
|
|
|
Execute the commands found in the alias
|
|
|
|
.Ar c .
|
|
|
|
.El
|
|
|
|
.Pp
|
|
|
|
Intra-line movement commands:
|
|
|
|
.Bl -tag -width Ds
|
|
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|
.It Xo
|
|
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|
.Oo Ar n Oc Ns h and
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|
.Oo Ar n Oc Ns ^H
|
|
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|
.Xc
|
|
|
|
Move left
|
|
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|
.Ar n
|
|
|
|
characters.
|
|
|
|
.It Xo
|
|
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|
.Oo Ar n Oc Ns l and
|
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|
.Oo Ar n Oc Ns Aq space
|
|
|
|
.Xc
|
|
|
|
Move right
|
|
|
|
.Ar n
|
|
|
|
characters.
|
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|
.It 0
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|
Move to column 0.
|
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|
.It ^
|
|
|
|
Move to the first non-whitespace character.
|
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|
.It Xo
|
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|
.Oo Ar n Oc Ns \*(Ba
|
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.Xc
|
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|
|
Move to column
|
|
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|
.Ar n .
|
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|
.It $
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|
Move to the last character.
|
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|
.It Xo
|
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|
.Oo Ar n Oc Ns b
|
|
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|
.Xc
|
|
|
|
Move back
|
|
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|
.Ar n
|
|
|
|
words.
|
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|
.It Xo
|
|
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|
.Oo Ar n Oc Ns B
|
|
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|
.Xc
|
|
|
|
Move back
|
|
|
|
.Ar n
|
|
|
|
big-words.
|
|
|
|
.It Xo
|
|
|
|
.Oo Ar n Oc Ns e
|
|
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|
.Xc
|
|
|
|
Move forward to the end of the word,
|
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|
|
.Ar n
|
|
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|
times.
|
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|
.It Xo
|
|
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|
.Oo Ar n Oc Ns E
|
|
|
|
.Xc
|
|
|
|
Move forward to the end of the big-word,
|
|
|
|
.Ar n
|
|
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|
times.
|
|
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|
.It Xo
|
|
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|
.Oo Ar n Oc Ns w
|
|
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|
.Xc
|
|
|
|
Move forward
|
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|
.Ar n
|
|
|
|
words.
|
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|
.It Xo
|
|
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|
.Oo Ar n Oc Ns W
|
|
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|
.Xc
|
|
|
|
Move forward
|
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|
.Ar n
|
|
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|
big-words.
|
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|
.It %
|
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|
Find match.
|
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|
|
The editor looks forward for the nearest parenthesis, bracket, or
|
|
|
|
brace and then moves the cursor to the matching parenthesis, bracket, or brace.
|
|
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|
.It Xo
|
|
|
|
.Oo Ar n Oc Ns f Ns Ar c
|
|
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|
.Xc
|
|
|
|
Move forward to the
|
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|
.Ar n Ns th
|
|
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|
occurrence of the character
|
|
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|
.Ar c .
|
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|
.It Xo
|
|
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|
.Oo Ar n Oc Ns F Ns Ar c
|
|
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|
.Xc
|
|
|
|
Move backward to the
|
|
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|
.Ar n Ns th
|
|
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|
occurrence of the character
|
|
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|
.Ar c .
|
|
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|
.It Xo
|
|
|
|
.Oo Ar n Oc Ns t Ns Ar c
|
|
|
|
.Xc
|
|
|
|
Move forward to just before the
|
|
|
|
.Ar n Ns th
|
|
|
|
occurrence of the character
|
|
|
|
.Ar c .
|
|
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|
.It Xo
|
|
|
|
.Oo Ar n Oc Ns T Ns Ar c
|
|
|
|
.Xc
|
|
|
|
Move backward to just before the
|
|
|
|
.Ar n Ns th
|
|
|
|
occurrence of the character
|
|
|
|
.Ar c .
|
|
|
|
.It Xo
|
|
|
|
.Oo Ar n Oc Ns \&;
|
|
|
|
.Xc
|
|
|
|
Repeats the last
|
|
|
|
.Ic f , F , t ,
|
|
|
|
or
|
|
|
|
.Ic T
|
|
|
|
command.
|
|
|
|
.It Xo
|
|
|
|
.Oo Ar n Oc Ns \&,
|
|
|
|
.Xc
|
|
|
|
Repeats the last
|
|
|
|
.Ic f , F , t ,
|
|
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|
or
|
|
|
|
.Ic T
|
|
|
|
command, but moves in the opposite direction.
|
|
|
|
.El
|
|
|
|
.Pp
|
|
|
|
Inter-line movement commands:
|
|
|
|
.Bl -tag -width Ds
|
|
|
|
.It Xo
|
|
|
|
.Oo Ar n Oc Ns j ,
|
|
|
|
.Oo Ar n Oc Ns + ,
|
|
|
|
.No and
|
|
|
|
.Oo Ar n Oc Ns ^N
|
|
|
|
.Xc
|
|
|
|
Move to the
|
|
|
|
.Ar n Ns th
|
|
|
|
next line in the history.
|
|
|
|
.It Xo
|
|
|
|
.Oo Ar n Oc Ns k ,
|
|
|
|
.Oo Ar n Oc Ns - ,
|
|
|
|
.No and
|
|
|
|
.Oo Ar n Oc Ns ^P
|
|
|
|
.Xc
|
|
|
|
Move to the
|
|
|
|
.Ar n Ns th
|
|
|
|
previous line in the history.
|
|
|
|
.It Xo
|
|
|
|
.Oo Ar n Oc Ns G
|
|
|
|
.Xc
|
|
|
|
Move to line
|
|
|
|
.Ar n
|
|
|
|
in the history; if
|
|
|
|
.Ar n
|
|
|
|
is not specified, the number of the first remembered line is used.
|
|
|
|
.It Xo
|
|
|
|
.Oo Ar n Oc Ns g
|
|
|
|
.Xc
|
|
|
|
Like
|
|
|
|
.Ic G ,
|
|
|
|
except if
|
|
|
|
.Ar n
|
|
|
|
is not specified, it goes to the most recent remembered line.
|
|
|
|
.It Xo
|
|
|
|
.Oo Ar n Oc Ns / Ns Ar string
|
|
|
|
.Xc
|
|
|
|
Search backward through the history for the
|
|
|
|
.Ar n Ns th
|
|
|
|
line containing
|
|
|
|
.Ar string ;
|
|
|
|
if
|
|
|
|
.Ar string
|
|
|
|
starts with
|
|
|
|
.Ql ^ ,
|
|
|
|
the remainder of the string must appear at the start of the history line for
|
|
|
|
it to match.
|
|
|
|
.It Xo
|
|
|
|
.Oo Ar n Oc Ns \&? Ns Ar string
|
|
|
|
.Xc
|
|
|
|
Same as
|
|
|
|
.Ic / ,
|
|
|
|
except it searches forward through the history.
|
|
|
|
.It Xo
|
|
|
|
.Oo Ar n Oc Ns n
|
|
|
|
.Xc
|
|
|
|
Search for the
|
|
|
|
.Ar n Ns th
|
|
|
|
occurrence of the last search string; the directory of the search is the same
|
|
|
|
as the last search.
|
|
|
|
.It Xo
|
|
|
|
.Oo Ar n Oc Ns N
|
|
|
|
.Xc
|
|
|
|
Search for the
|
|
|
|
.Ar n Ns th
|
|
|
|
occurrence of the last search string; the directory of the search is the
|
|
|
|
opposite of the last search.
|
|
|
|
.El
|
|
|
|
.Pp
|
|
|
|
Edit commands
|
|
|
|
.Bl -tag -width Ds
|
|
|
|
.It Xo
|
|
|
|
.Oo Ar n Oc Ns a
|
|
|
|
.Xc
|
|
|
|
Append text
|
|
|
|
.Ar n
|
|
|
|
times; goes into insert mode just after the current position.
|
|
|
|
The append is
|
|
|
|
only replicated if command mode is re-entered i.e.\&
|
|
|
|
.Aq esc
|
|
|
|
is used.
|
|
|
|
.It Xo
|
|
|
|
.Oo Ar n Oc Ns A
|
|
|
|
.Xc
|
|
|
|
Same as
|
|
|
|
.Ic a ,
|
|
|
|
except it appends at the end of the line.
|
|
|
|
.It Xo
|
|
|
|
.Oo Ar n Oc Ns i
|
|
|
|
.Xc
|
|
|
|
Insert text
|
|
|
|
.Ar n
|
|
|
|
times; goes into insert mode at the current position.
|
|
|
|
The insertion is only
|
|
|
|
replicated if command mode is re-entered i.e.\&
|
|
|
|
.Aq esc
|
|
|
|
is used.
|
|
|
|
.It Xo
|
|
|
|
.Oo Ar n Oc Ns I
|
|
|
|
.Xc
|
|
|
|
Same as
|
|
|
|
.Ic i ,
|
|
|
|
except the insertion is done just before the first non-blank character.
|
|
|
|
.It Xo
|
|
|
|
.Oo Ar n Oc Ns s
|
|
|
|
.Xc
|
|
|
|
Substitute the next
|
|
|
|
.Ar n
|
|
|
|
characters (i.e. delete the characters and go into insert mode).
|
|
|
|
.It S
|
|
|
|
Substitute whole line.
|
|
|
|
All characters from the first non-blank character to the
|
|
|
|
end of the line are deleted and insert mode is entered.
|
|
|
|
.It Xo
|
|
|
|
.Oo Ar n Oc Ns c Ns Ar move-cmd
|
|
|
|
.Xc
|
|
|
|
Change from the current position to the position resulting from
|
|
|
|
.Ar n move-cmd Ns s
|
|
|
|
(i.e. delete the indicated region and go into insert mode); if
|
|
|
|
.Ar move-cmd
|
|
|
|
is
|
|
|
|
.Ic c ,
|
|
|
|
the line starting from the first non-blank character is changed.
|
|
|
|
.It C
|
|
|
|
Change from the current position to the end of the line (i.e. delete to the
|
|
|
|
end of the line and go into insert mode).
|
|
|
|
.It Xo
|
|
|
|
.Oo Ar n Oc Ns x
|
|
|
|
.Xc
|
|
|
|
Delete the next
|
|
|
|
.Ar n
|
|
|
|
characters.
|
|
|
|
.It Xo
|
|
|
|
.Oo Ar n Oc Ns X
|
|
|
|
.Xc
|
|
|
|
Delete the previous
|
|
|
|
.Ar n
|
|
|
|
characters.
|
|
|
|
.It D
|
|
|
|
Delete to the end of the line.
|
|
|
|
.It Xo
|
|
|
|
.Oo Ar n Oc Ns d Ns Ar move-cmd
|
|
|
|
.Xc
|
|
|
|
Delete from the current position to the position resulting from
|
|
|
|
.Ar n move-cmd Ns s ;
|
|
|
|
.Ar move-cmd
|
|
|
|
is a movement command (see above) or
|
|
|
|
.Ic d ,
|
|
|
|
in which case the current line is deleted.
|
|
|
|
.It Xo
|
|
|
|
.Oo Ar n Oc Ns r Ns Ar c
|
|
|
|
.Xc
|
|
|
|
Replace the next
|
|
|
|
.Ar n
|
|
|
|
characters with the character
|
|
|
|
.Ar c .
|
|
|
|
.It Xo
|
|
|
|
.Oo Ar n Oc Ns R
|
|
|
|
.Xc
|
|
|
|
Replace.
|
|
|
|
Enter insert mode but overwrite existing characters instead of
|
|
|
|
inserting before existing characters.
|
|
|
|
The replacement is repeated
|
|
|
|
.Ar n
|
|
|
|
times.
|
|
|
|
.It Xo
|
|
|
|
.Oo Ar n Oc Ns ~
|
|
|
|
.Xc
|
|
|
|
Change the case of the next
|
|
|
|
.Ar n
|
|
|
|
characters.
|
|
|
|
.It Xo
|
|
|
|
.Oo Ar n Oc Ns y Ns Ar move-cmd
|
|
|
|
.Xc
|
|
|
|
Yank from the current position to the position resulting from
|
|
|
|
.Ar n move-cmd Ns s
|
|
|
|
into the yank buffer; if
|
|
|
|
.Ar move-cmd
|
|
|
|
is
|
|
|
|
.Ic y ,
|
|
|
|
the whole line is yanked.
|
|
|
|
.It Y
|
|
|
|
Yank from the current position to the end of the line.
|
|
|
|
.It Xo
|
|
|
|
.Oo Ar n Oc Ns p
|
|
|
|
.Xc
|
|
|
|
Paste the contents of the yank buffer just after the current position,
|
|
|
|
.Ar n
|
|
|
|
times.
|
|
|
|
.It Xo
|
|
|
|
.Oo Ar n Oc Ns P
|
|
|
|
.Xc
|
|
|
|
Same as
|
|
|
|
.Ic p ,
|
|
|
|
except the buffer is pasted at the current position.
|
|
|
|
.El
|
|
|
|
.Pp
|
|
|
|
Miscellaneous vi commands
|
|
|
|
.Bl -tag -width Ds
|
|
|
|
.It ^J and ^M
|
|
|
|
The current line is read, parsed, and executed by the shell.
|
|
|
|
.It ^L and ^R
|
|
|
|
Redraw the current line.
|
|
|
|
.It Xo
|
|
|
|
.Oo Ar n Oc Ns \&.
|
|
|
|
.Xc
|
|
|
|
Redo the last edit command
|
|
|
|
.Ar n
|
|
|
|
times.
|
|
|
|
.It u
|
|
|
|
Undo the last edit command.
|
|
|
|
.It U
|
|
|
|
Undo all changes that have been made to the current line.
|
|
|
|
.It Ar intr No and Ar quit
|
|
|
|
The interrupt and quit terminal characters cause the current line to be
|
|
|
|
deleted and a new prompt to be printed.
|
|
|
|
.El
|
|
|
|
.Sh FILES
|
|
|
|
.Bl -tag -width "/etc/suid_profileXX" -compact
|
2006-05-08 13:42:36 +02:00
|
|
|
.It Pa ~/.mkshrc
|
2006-06-21 21:27:35 +02:00
|
|
|
User's startup script (interactive shells).
|
2006-05-08 13:42:36 +02:00
|
|
|
Used only if
|
|
|
|
.Ev ENV
|
2006-05-08 13:59:41 +02:00
|
|
|
is unset or empty.
|
2005-05-23 05:06:10 +02:00
|
|
|
.It Pa ~/.profile
|
|
|
|
User's login profile.
|
|
|
|
.It Pa /etc/profile
|
|
|
|
System login profile.
|
|
|
|
.It Pa /etc/shells
|
|
|
|
Shell database.
|
2005-11-22 19:09:18 +01:00
|
|
|
.It Pa /etc/suid_profile
|
|
|
|
Privileged shell profile.
|
2005-05-23 05:06:10 +02:00
|
|
|
.El
|
|
|
|
.Sh SEE ALSO
|
|
|
|
.Xr arc4random 1 ,
|
|
|
|
.Xr awk 1 ,
|
|
|
|
.Xr ed 1 ,
|
|
|
|
.Xr getconf 1 ,
|
|
|
|
.Xr getopt 1 ,
|
|
|
|
.Xr sed 1 ,
|
|
|
|
.Xr sh 1 ,
|
|
|
|
.Xr stty 1 ,
|
|
|
|
.Xr dup 2 ,
|
|
|
|
.Xr execve 2 ,
|
|
|
|
.Xr getgid 2 ,
|
|
|
|
.Xr getuid 2 ,
|
2005-10-21 14:41:56 +02:00
|
|
|
.Xr mknod 2 ,
|
|
|
|
.Xr mkfifo 2 ,
|
2005-05-23 05:06:10 +02:00
|
|
|
.Xr open 2 ,
|
|
|
|
.Xr pipe 2 ,
|
|
|
|
.Xr wait 2 ,
|
|
|
|
.Xr getopt 3 ,
|
|
|
|
.Xr rand 3 ,
|
|
|
|
.Xr signal 3 ,
|
|
|
|
.Xr srand 3 ,
|
|
|
|
.Xr system 3 ,
|
|
|
|
.Xr tty 4 ,
|
|
|
|
.Xr shells 5 ,
|
|
|
|
.Xr environ 7 ,
|
2005-10-21 14:41:56 +02:00
|
|
|
.Xr script 7 ,
|
|
|
|
.Xr mknod 8
|
2005-05-23 05:06:10 +02:00
|
|
|
.Pp
|
|
|
|
.Pa http://docsrv.sco.com:507/en/man/html.C/sh.C.html
|
|
|
|
.Rs
|
|
|
|
.%A Morris Bolsky
|
2006-07-27 16:45:30 +02:00
|
|
|
.%B "The KornShell Command and Programming Language"
|
|
|
|
.%D 1989
|
|
|
|
.%I "Prentice Hall PTR"
|
|
|
|
.%P "xvi\ +\ 356 pages"
|
|
|
|
.%O "ISBN 978\-0\-13\-516972\-8 (0\-13\-516972\-0)"
|
|
|
|
.Re
|
|
|
|
.Rs
|
|
|
|
.%A Morris I. Bolsky
|
|
|
|
.%A David G. Korn
|
|
|
|
.%B "The New KornShell Command and Programming Language (2nd Edition)"
|
|
|
|
.%D 1995
|
|
|
|
.%I "Prentice Hall PTR"
|
|
|
|
.%P "xvi\ +\ 400 pages"
|
|
|
|
.%O "ISBN 978\-0\-13\-182700\-4 (0\-13\-182700\-6)"
|
2005-05-23 05:06:10 +02:00
|
|
|
.Re
|
|
|
|
.Rs
|
|
|
|
.%A Stephen G. Kochan
|
|
|
|
.%A Patrick H. Wood
|
2006-07-27 16:45:30 +02:00
|
|
|
.%B "UNIX Shell Programming"
|
|
|
|
.%V "Revised Edition"
|
|
|
|
.%D 1990
|
|
|
|
.%I "Hayden"
|
|
|
|
.%P "xi\ +\ 490 pages"
|
|
|
|
.%O "ISBN 978\-0\-672\-48448\-3 (0\-672\-48448\-X)"
|
2005-05-23 05:06:10 +02:00
|
|
|
.Re
|
|
|
|
.Rs
|
|
|
|
.%A "IEEE Inc."
|
2006-07-27 16:45:30 +02:00
|
|
|
.%B "IEEE Standard for Information Technology \- Portable Operating System Interface (POSIX)"
|
|
|
|
.%V "Part 2: Shell and Utilities"
|
2005-05-23 05:06:10 +02:00
|
|
|
.%D 1993
|
2006-07-27 16:45:30 +02:00
|
|
|
.%I "IEEE Press"
|
|
|
|
.%P "xvii\ +\ 1195 pages"
|
|
|
|
.%O "ISBN 978\-1\-55937\-255\-8 (1\-55937\-255\-9)"
|
2005-05-23 05:06:10 +02:00
|
|
|
.Re
|
2006-05-10 21:30:33 +02:00
|
|
|
.Rs
|
|
|
|
.%A Bill Rosenblatt
|
2006-07-27 16:45:30 +02:00
|
|
|
.%B "Learning the Korn Shell"
|
2006-05-10 21:30:33 +02:00
|
|
|
.%D 1993
|
2006-07-27 16:45:30 +02:00
|
|
|
.%I "O'Reilly"
|
|
|
|
.%P "360 pages"
|
|
|
|
.%O "ISBN 978\-1\-56592\-054\-5 (1\-56592\-054\-6)"
|
2006-05-10 21:30:33 +02:00
|
|
|
.Re
|
|
|
|
.Rs
|
|
|
|
.%A Bill Rosenblatt
|
|
|
|
.%A Arnold Robbins
|
2006-07-27 16:45:30 +02:00
|
|
|
.%B "Learning the Korn Shell, Second Edition"
|
2006-05-10 21:30:33 +02:00
|
|
|
.%D 2002
|
2006-07-27 16:45:30 +02:00
|
|
|
.%I "O'Reilly"
|
|
|
|
.%P "432 pages"
|
|
|
|
.%O "ISBN 978\-0\-596\-00195\-7 (0\-596\-00195\-9)"
|
|
|
|
.Re
|
|
|
|
.Rs
|
|
|
|
.%A Barry Rosenberg
|
|
|
|
.%B "KornShell Programming Tutorial"
|
|
|
|
.%D 1991
|
|
|
|
.%I "Addison\-Wesley Professional"
|
|
|
|
.%P "xxi\ +\ 324 pages"
|
|
|
|
.%O "ISBN 978\-0\-201\-56324\-5 (0\-201\-56324\-X)"
|
2006-05-10 21:30:33 +02:00
|
|
|
.Re
|
2005-05-23 05:06:10 +02:00
|
|
|
.Sh AUTHORS
|
2006-07-27 16:45:30 +02:00
|
|
|
This shell was based on the public domain korn shell
|
|
|
|
and is currently maintained by
|
|
|
|
.An Thorsten Glaser Aq tg@mirbsd.de .
|
2005-05-23 05:06:10 +02:00
|
|
|
It has been developed further by the MirOS project
|
2005-11-22 19:36:20 +01:00
|
|
|
incorporating changes from the Debian and OpenBSD
|
2006-07-27 16:45:30 +02:00
|
|
|
projects and patches and suggestions from users
|
|
|
|
and many other persons.
|
2005-05-23 05:06:10 +02:00
|
|
|
.Sh BUGS
|
2006-05-10 21:30:33 +02:00
|
|
|
This document attempts to describe
|
2006-08-02 15:32:18 +02:00
|
|
|
.Nm "" R28 .
|
2005-05-23 05:06:10 +02:00
|
|
|
Please report bugs in
|
|
|
|
.Nm
|
2006-08-23 00:49:38 +02:00
|
|
|
to the
|
2006-08-11 15:46:32 +02:00
|
|
|
.Aq miros-discuss@mirbsd.org
|
2006-08-23 00:49:38 +02:00
|
|
|
mailing list or in the
|
2006-08-11 15:46:32 +02:00
|
|
|
.Li \&#mksh
|
2006-08-23 00:49:38 +02:00
|
|
|
or
|
|
|
|
.Li \&#ksh
|
|
|
|
IRC channel at
|
|
|
|
.Pa irc.freenode.net .
|
2005-05-23 05:06:10 +02:00
|
|
|
.Pp
|
|
|
|
By the way, the most frequently reported bug is:
|
|
|
|
.Bd -literal -offset indent
|
2006-01-27 11:58:36 +01:00
|
|
|
$ print hi \*(Ba read a; print $a # Does not show hi
|
2005-05-23 05:06:10 +02:00
|
|
|
.Ed
|
|
|
|
.Pp
|
|
|
|
This does not work because the last command of a pipe sequence
|
2006-08-23 00:49:38 +02:00
|
|
|
is executed in a subshell.
|
2006-08-28 05:31:01 +02:00
|
|
|
This is an
|
2006-08-23 00:49:38 +02:00
|
|
|
.Nm
|
|
|
|
feature which can be depended on by scripts.
|
2006-08-14 22:41:21 +02:00
|
|
|
Use co-routines to work around if necessary and possible.
|