Cygwin Utilities
Cygwin comes with a number of command-line utilities that are used to
manage the UNIX emulation portion of the Cygwin environment. While many of
these reflect their UNIX counterparts, each was written specifically for
Cygwin. You may use the long or short option names interchangeably; for
example, --help and -h function
identically. All of the Cygwin command-line utilities support the
--help and --version options.
chattr
1
Cygwin Utilities
chattr
Change file attributes
chattr [-RVfhv] [+-=mode]... [file]...
Options
-R, --recursive recursively list attributes of directories and their
contents
-V, --verbose Be verbose during operation
-f, --force suppress error messages
-h, --help this help text
-v, --version display the program version
Description
The chattr program allows to change file
attributes, namely DOS attributes, as well as making files sparse,
encrypt or compress them on FS level, or setting directories'
case sensitivity.
The format of 'mode' is {+-=}[acCehnrsSt]
The operator '+' causes the selected attributes to be added to the
existing attributes of the files; '-' causes them to be removed; and
'=' causes them to be the only attributes that the files have.
Supported attributes:
'r', 'Readonly': file is read-only
'h', 'Hidden': file or directory is hidden
's', 'System': file or directory that the operating system uses
'a', 'Archive': file or directory has the archive marker set
't', 'Temporary': file is being used for temporary storage
'S', 'Sparse': file is sparse
'c', 'Compressed': file or directory is compressed
'n', 'Notindexed': file or directory is not to be indexed by the
content indexing service
'e', 'Encrypted': file is encrypted
'C', 'Casesensitive': directory is handled case sensitive
(Windows 10 1803 or later, local NTFS only,
WSL must be installed)
cygcheck
1
Cygwin Utilities
cygcheck
List system information, check installed packages, or query package database
cygcheck [-v] [-h] PROGRAM
cygcheck -c [-d] [PACKAGE]
cygcheck -s [-r] [-v] [-h]
cygcheck -k
cygcheck -f FILE [FILE]...
cygcheck -l [PACKAGE]...
cygcheck -p REGEXP
cygcheck --delete-orphaned-installation-keys
cygcheck -h
Options
At least one command option or a PROGRAM is required, as shown above.
PROGRAM list library (DLL) dependencies of PROGRAM
-c, --check-setup show installed version of PACKAGE and verify integrity
(or for all installed packages if none specified)
-d, --dump-only just list packages, do not verify (with -c)
-s, --sysinfo produce diagnostic system information (implies -c -d)
-r, --registry also scan registry for Cygwin settings (with -s)
-k, --keycheck perform a keyboard check session (must be run from a
plain console only, not from a pty/rxvt/xterm)
-f, --find-package find the package to which FILE belongs
-l, --list-package list contents of PACKAGE (or all packages if none given)
-p, --package-query search for REGEXP in the entire cygwin.com package
repository (requires internet connectivity)
--delete-orphaned-installation-keys
Delete installation keys of old, now unused
installations from the registry. Requires the right
to change the registry.
-v, --verbose produce more verbose output
-h, --help annotate output with explanatory comments when given
with another command, otherwise print this help
-V, --version print the version of cygcheck and exit
Note: -c, -f, and -l only report on packages that are currently installed. To
search all official Cygwin packages use -p instead. The -p REGEXP matches
package names, descriptions, and names of files/paths within all packages.
Description
The cygcheck program is a diagnostic utility for
dealing with Cygwin programs. If you are familiar with
dpkg or rpm,
cygcheck is similar in many ways. (The major
difference is that setup.exe handles installing and
uninstalling packages; see for more
information.)
The -c option checks the version and status of
installed Cygwin packages. If you specify one or more package names,
cygcheck will limit its output to those packages, or
with no arguments it lists all packages. A package will be marked
Incomplete if files originally installed are no longer
present. The best thing to do in that situation is reinstall the package
with setup.exe. To see which files are missing, use
the -v option. If you do not need to know the status
of each package and want cygcheck to run faster, add
the -d option and cygcheck will
only output the name and version for each package.
If you list one or more programs on the command line,
cygcheck will diagnose the runtime environment of that
program or programs, providing the names of DLL files on which the
program depends. If you specify the -s option,
cygcheck will give general system information. If you
list one or more programs on the command line and specify
-s, cygcheck will report on
both.
The -f option helps you to track down which
package a file came from, and -l lists all files in a
package. For example, to find out about
/usr/bin/less and its package:
Example cygcheck
usage
$ cygcheck -f /usr/bin/less
less-381-1
$ cygcheck -l less
/usr/bin/less.exe
/usr/bin/lessecho.exe
/usr/bin/lesskey.exe
/usr/man/man1/less.1
/usr/man/man1/lesskey.1
The -h option prints additional helpful messages
in the report, at the beginning of each section. It also adds table
column headings. While this is useful information, it also adds some to
the size of the report, so if you want a compact report or if you know
what everything is already, just leave this out.
The -v option causes the output to be more
verbose. What this means is that additional information will be reported
which is usually not interesting, such as the internal version numbers of
DLLs, additional information about recursive DLL usage, and if a file in
one directory in the PATH also occurs in other directories on the PATH.
The -r option causes cygcheck
to search your registry for information that is relevant to Cygwin
programs. These registry entries are the ones that have "Cygwin" in the
name. If you are paranoid about privacy, you may remove information from
this report, but please keep in mind that doing so makes it harder to
diagnose your problems.
In contrast to the other options that search the packages that are
installed on your local system, the -p option can be
used to search the entire official Cygwin package repository. It takes as
argument a Perl-compatible regular expression which is used to match
package names, package descriptions, and path/filenames of the contents
of packages. This feature requires an active internet connection, since
it must query the cygwin.com web site. In fact, it is
equivalent to the search that is available on the Cygwin package listing
page.
For example, perhaps you are getting an error because you are missing
a certain DLL and you want to know which package includes that file:
Searching all packages for a
file
$ cygcheck -p 'cygintl-2\.dll'
Found 1 matches for 'cygintl-2\.dll'.
libintl2-0.12.1-3 GNU Internationalization runtime library
$ cygcheck -p 'libexpat.*\.a'
Found 2 matches for 'libexpat.*\.a'.
expat-1.95.7-1 XML parser library written in C
expat-1.95.8-1 XML parser library written in C
$ cygcheck -p '/ls\.exe'
Found 2 matches for '/ls\.exe'.
coreutils-5.2.1-5 GNU core utilities (includes fileutils, sh-utils and textutils)
coreutils-5.3.0-6 GNU core utilities (includes fileutils, sh-utils and textutils)
Note that this option takes a regular expression, not a glob or
wildcard. This means that you need to use .* if you
want something similar to the wildcard * commonly used
in filename globbing. Similarly, to match the period character you should
use \. since the . character in a
regexp is a metacharacter that will match any character. Also be aware
that the characters such as \ and *
are shell metacharacters, so they must be either escaped or quoted, as in
the example above.
The third example above illustrates that if you want to match a whole
filename, you should include the / path seperator. In
the given example this ensures that filenames that happen to end in
ls.exe such as ncftpls.exe are not
shown. Note that this use does not mean "look for packages with
ls in the root directory," since the
/ can match anywhere in the path. It's just there to
anchor the match so that it matches a full filename.
By default the matching is case-sensitive. To get a case insensitive
match, begin your regexp with (?i) which is a
PCRE-specific feature. For complete documentation on Perl-compatible
regular expression syntax and options, read the perlre
manpage, or one of many websites such as perldoc.com
that document the Perl language.
The cygcheck program should be used to send
information about your system for troubleshooting when requested. When
asked to run this command save the output so that you can email it, for
example:
$ cygcheck -s -v -r -h > cygcheck_output.txt
Each Cygwin DLL stores its path and installation key in the
registry. This allows troubleshooting of problems which could be a result
of having multiple concurrent Cygwin installations. However, if you're
experimenting a lot with different Cygwin installation paths, your
registry could accumulate a lot of old Cygwin installation entries for
which the installation doesn't exist anymore. To get rid of these
orphaned registry entries, use the cygcheck
--delete-orphaned-installation-keys command.
cygpath
1
Cygwin Utilities
cygpath
Convert Unix and Windows format paths, or output system path information
cygpath (-d|-m|-u|-w|-t TYPE) [-f FILE] [OPTION]... NAME...
cygpath [-c HANDLE]
cygpath [-ADHOPSW]
cygpath [-F ID]
Options
Output type options:
-d, --dos print DOS (short) form of NAMEs (C:\PROGRA~1\)
-m, --mixed like --windows, but with regular slashes (C:/WINNT)
-M, --mode report on mode of file (currently binmode or textmode)
-u, --unix (default) print Unix form of NAMEs (/cygdrive/c/winnt)
-w, --windows print Windows form of NAMEs (C:\WINNT)
-t, --type TYPE print TYPE form: 'dos', 'mixed', 'unix', or 'windows'
Path conversion options:
-a, --absolute output absolute path
-l, --long-name print Windows long form of NAMEs (with -w, -m only)
-p, --path NAME is a PATH list (i.e., '/bin:/usr/bin')
-U, --proc-cygdrive Emit /proc/cygdrive path instead of cygdrive prefix
when converting Windows path to UNIX path.
-s, --short-name print DOS (short) form of NAMEs (with -w, -m only)
-C, --codepage CP print DOS, Windows, or mixed pathname in Windows
codepage CP. CP can be a numeric codepage identifier,
or one of the reserved words ANSI, OEM, or UTF8.
If this option is missing, cygpath defaults to the
character set defined by the current locale.
System information:
-A, --allusers use `All Users' instead of current user for -D, -P
-D, --desktop output `Desktop' directory and exit
-H, --homeroot output `Profiles' directory (home root) and exit
-O, --mydocs output `My Documents' directory and exit
-P, --smprograms output Start Menu `Programs' directory and exit
-S, --sysdir output system directory and exit
-W, --windir output `Windows' directory and exit
-F, --folder ID output special folder with numeric ID and exit
Other options:
-f, --file FILE read FILE for input; use - to read from STDIN
-o, --option read options from FILE as well (for use with --file)
-c, --close HANDLE close HANDLE (for use in captured process)
-i, --ignore ignore missing argument
-h, --help output usage information and exit
-V, --version output version information and exit
Description
The cygpath program is a utility that converts
Windows native filenames to Cygwin POSIX-style pathnames and vice versa.
It can be used when a Cygwin program needs to pass a file name to a
native Windows program, or expects to get a file name from a native
Windows program. Alternatively, cygpath can output
information about the location of important system directories in either
format.
The -u and -w options indicate
whether you want a conversion to UNIX (POSIX) format
(-u) or to Windows format (-w). Use
the -d to get DOS-style (8.3) file and path names. The
-m option will output Windows-style format but with
forward slashes instead of backslashes. This option is especially useful
in shell scripts, which use backslashes as an escape character.
In combination with the -w option, you can use
the -l and -s options to use normal
(long) or DOS-style (short) form. The -d option is
identical to -w and -s together.
The -C option allows to specify a Windows codepage
to print DOS and Windows paths created with one of the
-d, -m, or -w
options. The default is to use the character set of the current locale
defined by one of the internationalization environment variables
LC_ALL, LC_CTYPE, or LANG,
see . This is sometimes not sufficient for
interaction with native Windows tools, which might expect native,
non-ASCII characters in a specific Windows codepage. Console tools, for
instance, might expect pathnames in the current OEM codepage, while
graphical tools like Windows Explorer might expect pathnames in the
current ANSI codepage.
The -U option allows to use cygpath to create
unambiguous Unix paths pointing outside the Cygwin tree andf thus having
no explicit POSIX path. Those paths usually use the cygdrive prefix.
However, the cygdrive prefix can be changed by the user, so symbolic links
created using the cygdrive prefix are not foolproof. With
-U cygpath will generate such paths prepended by the
virtual /proc/cygdrive symbolic link, which will
never change, so the created path is safe against changing the cygdrive
prefix.
The -C option takes a single parameter:
ANSI, to specify the current ANSI
codepage
OEM, to specify the current OEM (console)
codepage
UTF8, to specify UTF-8.
A numerical, decimal codepage number, for instance 936 for GBK,
28593 for ISO-8859-3, etc. A full list of supported codepages is
listed on the Microsoft MSDN page Code Page Identifiers. A codepage of 0 is the same as if the
-C hasn't been specified at all.
The -p option means that you want to convert a
path-style string rather than a single filename. For example, the PATH
environment variable is semicolon-delimited in Windows, but
colon-delimited in UNIX. By giving -p you are
instructing cygpath to convert between these
formats.
The -i option supresses the print out of the usage
message if no filename argument was given. It can be used in make file
rules converting variables that may be omitted to a proper format. Note
that cygpath output may contain spaces (C:\Program
Files) so should be enclosed in quotes.
Example cygpath usage
The capital options -D, -H,
-P, -S, and -W
output directories used by Windows that are not the same on all systems,
for example -S might output C:\WINNT\system32 or
C:\Windows\System32. The -H shows the Windows profiles
directory that can be used as root of home. The -A
option forces use of the "All Users" directories instead of the current
user for the -D, -O and
-P options. The -F outputs other
special folders specified by their internal numeric code (decimal or
0x-prefixed hex). For valid codes and symbolic names, see the CSIDL_*
definitions in the include file /usr/include/w32api/shlobj.h from package
w32api. The current valid range of codes for folders is 0 (Desktop) to 59
(CDBurn area). By default the output is in UNIX (POSIX) format; use the
-w or -d options to get other
formats.
dumper
1
Cygwin Utilities
dumper
Dump core from WIN32PID to FILENAME.core
dumper [OPTION] FILENAME WIN32PID
Options
-d, --verbose be verbose while dumping
-h, --help output help information and exit
-q, --quiet be quiet while dumping (default)
-V, --version output version information and exit
Description
The dumper utility can be used to create a core
dump of running Windows process. This core dump can be later loaded to
gdb and analyzed. One common way to use
dumper is to plug it into cygwin's Just-In-Time
debugging facility by adding
error_start=x:\path\to\dumper.exe
to the
CYGWIN environment variable. Please note that
x:\path\to\dumper.exe is Windows-style and not cygwin
path. If error_start is set this way, then dumper will
be started whenever some program encounters a fatal error.
dumper can be also be started from the command
line to create a core dump of any running process. Unfortunately, because
of a Windows API limitation, when a core dump is created and
dumper exits, the target process is terminated too.
To save space in the core dump, dumper doesn't
write those portions of target process' memory space that are loaded from
executable and dll files and are unchangeable, such as program code and
debug info. Instead, dumper saves paths to files which
contain that data. When a core dump is loaded into gdb, it uses these
paths to load appropriate files. That means that if you create a core
dump on one machine and try to debug it on another, you'll need to place
identical copies of the executable and dlls in the same directories as on
the machine where the core dump was created.
getconf
1
Cygwin Utilities
getconf
Get configuration values
getconf [-v specification] variable_name [pathname]
getconf -a [pathname]
Options
-v specification Indicate specific version for which configuration
values shall be fetched.
-a, --all Print all known configuration values
Other options:
-h, --help This text
-V, --version Print program version and exit
Description
The getconf utility prints the value of the
configuration variable specified by variable_name. If
no pathname is given, getconf
serves as a wrapper for the confstr and
sysconf functions, supporting the symbolic constants
defined in the limits.h and
unistd.h headers, without their respective
_CS_ or _SC_ prefixes.
If pathname is given, getconf
prints the value of the configuration variable for the specified
pathname. In this form, getconf serves as a wrapper
for the pathconf function, supporting the symbolic
constants defined in the unistd.h header, without the
_PC_ prefix.
If you specify the -v option, the parameter
denotes a specification for which the value of the configuration variable
should be printed. Note that the only specifications supported by Cygwin
are POSIX_V7_ILP32_OFFBIG and the legacy
POSIX_V6_ILP32_OFFBIG and
XBS5_ILP32_OFFBIG equivalents.
Use the -a option to print a list of all available
configuration variables for the system, or given
pathname, and their values.
getfacl
1
Cygwin Utilities
getfacl
Display file and directory access control lists (ACLs)
getfacl [-adceEn] FILE [FILE2...]
Options
-a, --access display the file access control list only
-d, --default display the default access control list only
-c, --omit-header do not display the comment header
-e, --all-effective print all effective rights
-E, --no-effective print no effective rights
-n, --numeric print numeric user/group identifiers
-V, --version print version and exit
-h, --help this help text
When multiple files are specified on the command line, a blank
line separates the ACLs for each file.
Description
For each argument that is a regular file, special file or directory,
getfacl displays the owner, the group, and the ACL.
For directories getfacl displays additionally the
default ACL. With no options specified, getfacl
displays the filename, the owner, the group, the setuid (s), setgid (s),
and sticky (t) bits if available, and both the ACL and the default ACL,
if it exists. For more information on Cygwin and Windows ACLs, see
in the Cygwin User's Guide. The format
for ACL output is as follows:
# file: filename
# owner: name or uid
# group: name or uid
# flags: sst
user::perm
user:name or uid:perm
group::perm
group:name or gid:perm
mask:perm
other:perm
default:user::perm
default:user:name or uid:perm
default:group::perm
default:group:name or gid:perm
default:mask:perm
default:other:perm
kill
1
Cygwin Utilities
kill
Send signals to processes
kill [-f] [-signal] [-s signal] pid1 [pid2 ...]
kill -l [signal]
Options
-f, --force force, using win32 interface if necessary
-l, --list print a list of signal names
-s, --signal send signal (use kill --list for a list)
-W, --winpid specified pids are windows PIDs, not Cygwin PIDs
(use with extreme caution!)
-h, --help output usage information and exit
-V, --version output version information and exit
Description
The kill program allows you to send arbitrary
signals to other Cygwin programs. The usual purpose is to end a running
program from some other window when ^C won't work, but you can also send
program-specified signals such as SIGUSR1 to trigger actions within the
program, like enabling debugging or re-opening log files. Each program
defines the signals they understand.
You may need to specify the full path to use kill
from within some shells, including bash, the default
Cygwin shell. This is because bash defines a
kill builtin function; see the bash
man page under BUILTIN COMMANDS for more
information. To make sure you are using the Cygwin version, try
$ /bin/kill --version
which should give the Cygwin
kill version number and copyright information.
The -f option uses Windows functions to
terminate processes forcefully. Use -f to
terminate native Windows processes not started by Cygwin processes.
-f can also be useful to terminate Cygwin processes
not answering to SIGKILL.
Unless you specific the -W option, the "pid"
values used by kill are the Cygwin pids, not the
Windows pids. To get a list of running programs and their Cygwin pids,
use the Cygwin ps program. ps -W
will display all windows pids.
The kill -l option prints the name of the given
signal, or a list of all signal names if no signal is given.
To send a specific signal, use the -signN option,
either with a signal number or a signal name (minus the "SIG" part), as
shown in these examples:
Using the kill command
$ kill 123
$ kill -1 123
$ kill -HUP 123
$ kill -f 123
Here is a list of available signals, their numbers, and some
commentary on them, from the file
<sys/signal.h>, which should be considered the
official source of this information.
SIGHUP 1 hangup
SIGINT 2 interrupt
SIGQUIT 3 quit
SIGILL 4 illegal instruction (not reset when caught)
SIGTRAP 5 trace trap (not reset when caught)
SIGABRT 6 used by abort
SIGIOT 6 another name for SIGABRT
SIGEMT 7 EMT instruction
SIGFPE 8 floating point exception
SIGKILL 9 kill (cannot be caught or ignored)
SIGBUS 10 bus error
SIGSEGV 11 segmentation violation
SIGSYS 12 bad argument to system call
SIGPIPE 13 write on a pipe with no one to read it
SIGALRM 14 alarm clock
SIGTERM 15 software termination signal from kill
SIGURG 16 urgent condition on IO channel
SIGSTOP 17 sendable stop signal not from tty
SIGTSTP 18 stop signal from tty
SIGCONT 19 continue a stopped process
SIGCHLD 20 to parent on child stop or exit
SIGCLD 20 System V name for SIGCHLD
SIGTTIN 21 to readers pgrp upon background tty read
SIGTTOU 22 like TTIN for output if (tp->t_local<OSTOP)
SIGIO 23 input/output possible
SIGPOLL 23 System V name for SIGIO
SIGXCPU 24 exceeded CPU time limit
SIGXFSZ 25 exceeded file size limit
SIGVTALRM 26 virtual time alarm
SIGPROF 27 profiling time alarm
SIGWINCH 28 window changed
SIGLOST 29 resource lost (eg, record-lock lost)
SIGPWR 29 power failure
SIGUSR1 30 user defined signal 1
SIGUSR2 31 user defined signal 2
ldd
1
Cygwin Utilities
ldd
Print shared library dependencies
ldd [OPTION]... FILE...
Options
-h, --help print this help and exit
-V, --version print version information and exit
-r, --function-relocs process data and function relocations
(currently unimplemented)
-u, --unused print unused direct dependencies
(currently unimplemented)
-v, --verbose print all information
(currently unimplemented)
Description
ldd prints the shared libraries (DLLs) loaded
when running an executable or DLL.
Security
ldd invokes the Windows loader on the file specified,
then uses the Windows debugging interface to report DLLs loaded, and
(for executables) to attempt to stop execution before the entrypoint.
Thus, you should never use ldd on an untrusted file.
locale
1
Cygwin Utilities
locale
Get locale-specific information
locale [-amvhV]
locale [-ck] NAME
locale [-iusfnU]
Options
System information:
-a, --all-locales List all available supported locales
-m, --charmaps List all available character maps
-v, --verbose More verbose output
Modify output format:
-c, --category-name List information about given category NAME
-k, --keyword-name Print information about given keyword NAME
Default locale information:
-i, --input Print current input locale
-u, --user Print locale of user's default UI language
-s, --system Print locale of system default UI language
-f, --format Print locale of user's regional format settings
(time, numeric & monetary)
-n, --no-unicode Print system default locale for non-Unicode programs
-U, --utf Attach \".UTF-8\" to the result
Other options:
-h, --help This text
-V, --version Print program version and exit
Description
locale without parameters prints information about
the current locale environment settings.
The -i, -u,
-s, -f, and -n
options can be used to request the various Windows locale settings. The
purpose is to use this command in scripts to set the POSIX locale
variables.
The -i option prints the current input language.
This is called the "Input language" and basically equivalent to the
current keyboard layout setting.
The -u option prints the current user's Windows UI
locale to stdout. In Windows this setting is called the
"Display Language".
The -s option prints the systems default instead.
The -f option prints the user's setting for time,
date, number and currency. That's equivalent to the setting in the
"Formats" or "Regional Options" tab in the "Region and Language" or
"Regional and Language Options" dialog.
The -n option prints the system's default
language used for applications which don't support Unicode.
With the -U option locale
appends the string ".UTF-8" to enforce using UTF-8. Using UTF-8
as codeset is recommended.
Usage example:
bash$ export LANG=$(locale -uU)
bash$ echo $LANG
en_US.UTF-8
bash$ export LC_TIME=$(locale -fU)
bash$ echo $LC_TIME
de_DE.UTF-8
The -a option is helpful to learn which locales
are supported by your Windows machine. It prints all available locales
and the allowed modifiers. Example:
bash$ locale -a
C
C.utf8
POSIX
af_ZA
af_ZA.utf8
am_ET
am_ET.utf8
...
be_BY
be_BY.utf8
be_BY@latin
...
ca_ES
ca_ES.utf8
ca_ES@euro
catalan
...
The -v option prints more detailed information
about each available locale. Example:
bash$ locale -av
locale: af_ZA archive: /cygdrive/c/Windows/system32/kernel32.dll
-------------------------------------------------------------------------------
language | Afrikaans
territory | South Africa
codeset | ISO-8859-1
locale: af_ZA.utf8 archive: /cygdrive/c/Windows/system32/kernel32.dll
-------------------------------------------------------------------------------
language | Afrikaans
territory | South Africa
codeset | UTF-8
...
locale: ca_ES@euro archive: /cygdrive/c/Windows/system32/kernel32.dll
-------------------------------------------------------------------------------
language | Catalan
territory | Spain
codeset | ISO-8859-15
locale: catalan archive: /usr/share/locale/locale.alias
-------------------------------------------------------------------------------
language | Catalan
territory | Spain
codeset | ISO-8859-1
...
The -m option prints the names of the available
charmaps supported by Cygwin to stdout.
Otherwise, if arguments are given, locale prints
the values assigned to these arguments. Arguments can be names of locale
categories (for instance: LC_CTYPE, LC_MONETARY), or names of keywords
supported in the locale categories (for instance: thousands_sep,
charmap). The -c option prints additionally the name
of the category. The -k option prints additionally the
name of the keyword. Example:
bash$ locale -ck LC_MESSAGES
LC_MESSAGES
yesexpr="^[yY]"
noexpr="^[nN]"
yesstr="yes"
nostr="no"
messages-codeset="UTF-8"
bash$ locale noexpr
^[nN]
lsattr
1
Cygwin Utilities
lsattr
List file attributes
lsattr [-RVadhln] [file]...
Options
-R, --recursive recursively list attributes of directories and their
contents
-V, --version display the program version
-a, --all list all files in directories, including files that
start with '.'
-d, --directory list directories like other files, rather than listing
their contents.
-l, --long print options using long names instead of single
character abbreviations
-n, --no-headers don't print directory headers when recursing
-h, --help this help text
Description
The lsattr program allows to list file
attributes, namely DOS attributes, file sparseness, FS level
encryption and compression state, as well as directories'
case sensitivity setting.
Supported attributes:
'r', 'Readonly': file is read-only, directory is system-marked
'h', 'Hidden': file or directory is hidden
's', 'System': file or directory that the operating system uses
'a', 'Archive': file or directory has the archive marker set
't', 'Temporary': file is being used for temporary storage
'S', 'Sparse': file is sparse
'r', 'Reparse': file or directory that has a reparse point
'c', 'Compressed': file or directory is compressed
'o', 'Offline': the data of a file is moved to offline storage
'n', 'Notindexed': file or directory is not to be indexed by the
content indexing service
'e', 'Encrypted': file is encrypted
'C', 'Casesensitive': directory is handled case sensitive
(Windows 10 1803 or later, local NTFS only,
WSL must be installed)
minidumper
1
Cygwin Utilities
minidumper
Write minidump from WIN32PID to FILENAME.dmp
minidumper [OPTION] FILENAME WIN32PID
Options
-t, --type minidump type flags
-n, --nokill don't terminate the dumped process
-d, --verbose be verbose while dumping
-h, --help output help information and exit
-q, --quiet be quiet while dumping (default)
-V, --version output version information and exit
Description
The minidumper utility can be used to create a
minidump of a running Windows process. This minidump can be later
analysed using breakpad or Windows debugging tools.
minidumper can be used with cygwin's Just-In-Time
debugging facility in exactly the same way as dumper
(See ).
minidumper can also be started from the command line to
create a minidump of any running process. For compatibility with
dumper the target process is terminated after dumping
unless the -n option is given.
mkgroup
1
Cygwin Utilities
mkgroup
Write /etc/group-like output to stdout
mkgroup [OPTION]...
Options
Options:
-l,--local [machine] Print local group accounts of \"machine\",
from local machine if no machine specified.
Automatically adding machine prefix for local
machine depends on settings in /etc/nsswitch.conf.
-L,--Local machine Ditto, but generate groupname with machine prefix.
-d,--domain [domain] Print domain groups,
from current domain if no domain specified.
-c,--current Print current group.
-S,--separator char For -L use character char as domain\\group
separator in groupname instead of default '+'.
-o,--id-offset offset Change the default offset (0x10000) added to gids
-g,--group groupname Only return information for the specified group.
One of -l, -d must be specified, too.
-b,--no-builtin Don't print BUILTIN groups.
-U,--unix grouplist Print UNIX groups when using -l on a UNIX Samba
server. Grouplist is a comma-separated list of
groupnames or gid ranges (root,-25,50-100).
Enumerating large ranges can take a long time!
-h,--help Print this message.
-v,--version Print version information and exit.
Default is to print local groups on stand-alone machines, plus domain
groups on domain controllers and domain member machines.
Description
Don't use this command to generate a local /etc/group file, unless you
really need one. See the Cygwin User's Guide for more information.
The mkgroup program can be used to create a local
/etc/group file. Cygwin doesn't need this file,
because it reads group information from the Windows account databases,
but you can add an /etc/group file for instance, if
your machine is often disconnected from its domain controller.
Note that this information is static, in contrast to the information
automatically gathered by Cygwin from the Windows account databases. If
you change the group information on your system, you'll need to regenerate
the group file for it to have the new information.
By default, the information generated by mkgroup
is equivalent to the information generated by Cygwin itself. The
-d and -l/-L options allow you to
specify where the information comes from, some domain, or the local SAM
of a machine. Note that you can only enumerate accounts from trusted
domains. Any non-trusted domain will be ignored. Access-restrictions
of your current account apply. The -l/-L when used
with a machine name, tries to contact that machine to enumerate local
groups of other machines, typically outside of domains. This scenario
cannot be covered by Cygwin's account automatism. If you want to use
the -L option, but you don't like the default
domain/group separator from /etc/nsswitch.conf,
you can specify another separator using the -S option,
for instance:
Setting up group entry for current user with different
domain/group separator
$ mkgroup -L server1 -S= > /etc/group
For very simple needs, an entry for the current user's group can be
created by using the option -c.
The -o option allows for (unlikely) special cases
with multiple machines where the GIDs might match otherwise. The
-g option only prints the information for one group.
The -U option allows you to enumerate the standard
UNIX groups on a Samba machine. It's used together with -l
samba-server or -L samba-server. The normal
UNIX groups are usually not enumerated, but they can show up as a group
in ls -l output.
mkpasswd
1
Cygwin Utilities
mkpasswd
Write /etc/passwd-like output to stdout
mkpasswd [OPTIONS]...
Options
Options:
-l,--local [machine] Print local user accounts of \"machine\",
from local machine if no machine specified.
Automatically adding machine prefix for local
machine depends on settings in /etc/nsswitch.conf.
-L,--Local machine Ditto, but generate username with machine prefix.
-d,--domain [domain] Print domain accounts,
from current domain if no domain specified.
-c,--current Print current user.
-S,--separator char For -L use character char as domain\\user
separator in username instead of the default '+'.
-o,--id-offset offset Change the default offset (0x10000) added to uids
of foreign local machine accounts. Use with -l/-L.
-u,--username username Only return information for the specified user.
One of -l, -d must be specified, too
-b,--no-builtin Don't print BUILTIN users.
-p,--path-to-home path Use specified path instead of user account home dir
or /home prefix.
-U,--unix userlist Print UNIX users when using -l on a UNIX Samba
server. Userlist is a comma-separated list of
usernames or uid ranges (root,-25,50-100).
Enumerating large ranges can take a long time!
-h,--help Displays this message.
-V,--version Version information and exit.
Default is to print local accounts on stand-alone machines, domain accounts
on domain controllers and domain member machines.
Description
Don't use this command to generate a local /etc/passwd file, unless you
really need one. See the Cygwin User's Guide for more information.
The mkpasswd program can be used to create a
/etc/passwd file. Cygwin doesn't need this file,
because it reads user information from the Windows account databases,
but you can add an /etc/passwd file, for instance
if your machine is often disconnected from its domain controller.
Note that this information is static, in contrast to the information
automatically gathered by Cygwin from the Windows account databases. If
you change the user information on your system, you'll need to regenerate
the passwd file for it to have the new information.
By default, the information generated by mkpasswd
is equivalent to the information generated by Cygwin itself. The
-d and -l/-L options allow you to
specify where the information comes from, some domain, or the local SAM
of a machine. Note that you can only enumerate accounts from trusted
domains. Any non-trusted domain will be ignored. Access-restrictions
of your current account apply. The -l/-L when used
with a machine name, tries to contact that machine to enumerate local
groups of other machines, typically outside of domains. This scenario
cannot be covered by Cygwin's account automatism. If you want to use
the -L option, but you don't like the default
domain/group separator from /etc/nsswitch.conf,
you can specify another separator using the -S option,
analog to mkgroup.
For very simple needs, an entry for the current user can be created
by using the option -c.
The -o option allows for special cases (such as
multiple domains) where the UIDs might match otherwise. The
-p option causes mkpasswd to use
the specified prefix instead of the account home dir or /home/
. For example, this command:
Using an alternate home root
$ mkpasswd -l -p "$(cygpath -H)" > /etc/passwd
would put local users' home directories in the Windows
'Profiles' directory. The -u option creates just an
entry for the specified user. The -U option allows you
to enumerate the standard UNIX users on a Samba machine. It's used
together with -l samba-server or -L
samba-server. The normal UNIX users are usually not enumerated,
but they can show up as file owners in ls -l output.
mount
1
Cygwin Utilities
mount
Display information about mounted filesystems, or mount a filesystem
mount [OPTION] [<win32path> <posixpath>]
mount -a
mount <posixpath>
Options
-a, --all mount all filesystems mentioned in fstab
-c, --change-cygdrive-prefix change the cygdrive path prefix to <posixpath>
-f, --force force mount, don't warn about missing mount
point directories
-h, --help output usage information and exit
-m, --mount-entries write fstab entries to replicate mount points
and cygdrive prefixes
-o, --options X[,X...] specify mount options
-p, --show-cygdrive-prefix show user and/or system cygdrive path prefix
-V, --version output version information and exit
Description
The mount program is used to map your drives and
shares onto Cygwin's simulated POSIX directory tree, much like as is done
by mount commands on typical UNIX systems. However, in contrast to mount
points given in /etc/fstab, mount points created or
changed with mount are not persistent. They disappear
immediately after the last process of the current user exited. Please see
for more information on the concepts behind
the Cygwin POSIX file system and strategies for using mounts. To remove
mounts temporarily, use umount
Using mount
If you just type mount with no parameters, it
will display the current mount table for you.
Displaying the current set of mount points
$ mount
C:/cygwin/bin on /usr/bin type ntfs (binary)
C:/cygwin/lib on /usr/lib type ntfs (binary)
C:/cygwin on / type ntfs (binary)
C: on /mnt/c type ntfs (binary,user,noumount)
D: on /mnt/d type fat (binary,user,noumount)
In this example, c:/cygwin is the POSIX root and the D drive is
mapped to /mnt/d. Note that in this case, the root
mount is a system-wide mount point that is visible to all users running
Cygwin programs, whereas the /mnt/d mount is only
visible to the current user.
The mount utility is also the mechanism for
adding new mounts to the mount table in memory. The following example
demonstrates how to mount the directory
//pollux/home/joe/data to
/data for the duration of the current session.
Adding mount points
$ ls /data
ls: /data: No such file or directory
$ mount //pollux/home/joe/data /data
mount: warning - /data does not exist!
$ mount
//pollux/home/joe/data on /data type smbfs (binary)
C:/cygwin/bin on /usr/bin type ntfs (binary)
C:/cygwin/lib on /usr/lib type ntfs (binary)
C:/cygwin on / type ntfs (binary)
C: on /c type ntfs (binary,user,noumount)
D: on /d type fat (binary,user,noumount)
A given POSIX path may only exist once in the mount table. Attempts
to replace the mount will fail with a busy error. The
-f (force) option causes the old mount to be
silently replaced with the new one, provided the old mount point was a
user mount point. It's not valid to replace system-wide mount points.
Additionally, the -f option will silence warnings
about the non-existence of directories at the Win32 path
location.
The -o option is the method via which various
options about the mount point may be recorded. The following options
are available (note that most of the options are duplicates of other
mount flags):
acl - Use the filesystem's access control lists (ACLs) to
implement real POSIX permissions (default).
binary - Files default to binary mode (default).
bind - Allows to remount part of the file hierarchy somewhere else.
Different from other mount calls, the first argument
specifies an absolute POSIX path, rather than a Win32 path.
This POSIX path is remounted to the POSIX path specified as
the second parameter. The conversion to a Win32 path is done
within Cygwin immediately at the time of the call. Note that
symlinks are ignored while performing this path conversion.
cygexec - Treat all files below mount point as cygwin executables.
dos - Always convert leading spaces and trailing dots and spaces to
characters in the UNICODE private use area. This allows to use
broken filesystems which only allow DOS filenames, even if they
are not recognized as such by Cygwin.
exec - Treat all files below mount point as executable.
ihash - Always fake inode numbers rather than using the ones returned
by the filesystem. This allows to use broken filesystems which
don't return unambiguous inode numbers, even if they are not
recognized as such by Cygwin.
noacl - Ignore ACLs and fake POSIX permissions.
nosuid - No suid files are allowed (currently unimplemented)
notexec - Treat all files below mount point as not executable.
override - Override immutable mount points.
posix=0 - Switch off case sensitivity for paths under this mount point.
posix=1 - Switch on case sensitivity for paths under this mount point
(default).
sparse - Switch on support for sparse files. This option only makes
sense on NTFS and then only if you really need sparse files.
text - Files default to CRLF text mode line endings.
For a more complete description of the mount options and the
/etc/fstab file, see .
Note that all mount points added with mount are
user mount points. System mount points can only be specified in the
/etc/fstab file.
If you added mount points to /etc/fstab or
your /etc/fstab.d/<username> file, you can
add these mount points to your current user session using the
-a/--all option, or by specifing the posix path
alone on the command line. As an example, consider you added a mount
point with the POSIX path /my/mount. You can add
this mount point with either one of the following two commands to your
current user session.
$ mount /my/mount
$ mount -a
The first command just adds the /my/mount
mount point to your current session, the mount -a
adds all new mount points to your user session.
If you change a mount point to point to another native path, or if
you changed the flags of a mount point, you have to
umount the mount point first, before you can add it
again. Please note that all such added mount points are added as user
mount points, and that the rule that system mount points can't be
removed or replaced in a running session still applies.
To bind a POSIX path to another POSIX path, use the
bind mount flag.
$ mount -o bind /var /usr/var
This command makes the file hirarchy under
/var additionally available under
/usr/var.
The -m option causes the
mount utility to output the current mount table in a
series of fstab entries. You can save this output as a backup when
experimenting with the mount table. Copy the output to
/etc/fstab to restore the old state. It also makes
moving your settings to a different machine much easier.
Cygdrive mount points
Whenever Cygwin cannot use any of the existing mounts to convert
from a particular Win32 path to a POSIX one, Cygwin will, instead,
convert to a POSIX path using a default mount point:
/cygdrive. For example, if Cygwin accesses
z:\foo and the z drive is not currently in the
mount table, then z:\ will be accessible as
/cygdrive/z. The mount utility
can be used to change this default automount prefix through the use of
the "--change-cygdrive-prefix" option. In the following example, we
will set the automount prefix to /mnt:
Changing the default prefix
$ mount --change-cygdrive-prefix /mnt
Note that the cygdrive prefix can be set both per-user and
system-wide, and that as with all mounts, a user-specific mount takes
precedence over the system-wide setting. The mount
utility creates system-wide mounts by default if you do not specify a
type. You can always see the user and system cygdrive prefixes with the
-p option. Using the --options
flag with --change-cygdrive-prefix makes all new
automounted filesystems default to this set of options. For instance
(using the short form of the command line flags)
Changing the default prefix with specific mount options
$ mount -c /mnt -o binary,noacl
Limitations
Limitations: there is a hard-coded limit of 64 mount points.
Also, although you can mount to pathnames that do not start with "/",
there is no way to make use of such mount points.
Normally the POSIX mount point in Cygwin is an existing empty
directory, as in standard UNIX. If this is the case, or if there is a
place-holder for the mount point (such as a file, a symbolic link
pointing anywhere, or a non-empty directory), you will get the expected
behavior. Files present in a mount point directory before the mount
become invisible to Cygwin programs.
It is sometimes desirable to mount to a non-existent directory, for
example to avoid cluttering the root directory with names such as
a, b, c
pointing to disks. Although mount will give you a
warning, most everything will work properly when you refer to the mount
point explicitly. Some strange effects can occur however. For example
if your current working directory is /dir, say,
and /dir/mtpt is a mount point, then
mtpt will not show up in an ls
or echo * command and find . will
not find mtpt.
passwd
1
Cygwin Utilities
passwd
Change USER's password or password attributes.
passwd [OPTION] [USER]
Options
User operations:
-l, --lock lock USER's account.
-u, --unlock unlock USER's account.
-c, --cannot-change USER can't change password.
-C, --can-change USER can change password.
-e, --never-expires USER's password never expires.
-E, --expires USER's password expires according to system's
password aging rule.
-p, --pwd-not-required no password required for USER.
-P, --pwd-required password is required for USER.
-R, --reg-store-pwd enter password to store it in the registry for
later usage by services to be able to switch
to this user context with network credentials.
System operations:
-i, --inactive NUM set NUM of days before inactive accounts are disabled
(inactive accounts are those with expired passwords).
-n, --minage MINDAYS set system minimum password age to MINDAYS days.
-x, --maxage MAXDAYS set system maximum password age to MAXDAYS days.
-L, --length LEN set system minimum password length to LEN.
Other options:
-d, --logonserver SERVER connect to SERVER (e.g. domain controller).
Usually not required.
-S, --status display password status for USER (locked, expired,
etc.) plus global system password settings.
-h, --help output usage information and exit.
-V, --version output version information and exit.
If no option is given, change USER's password. If no user name is given,
operate on current user. System operations must not be mixed with user
operations. Don't specify a USER when triggering a system operation.
Don't specify a user or any other option together with the -R option.
Non-Admin users can only store their password if cygserver is running.
Note that storing even obfuscated passwords in the registry is not overly
secure. Use this feature only if the machine is adequately locked down.
Don't use this feature if you don't need network access within a remote
session. You can delete your stored password by using `passwd -R' and
specifying an empty password.
Description
passwd changes passwords for user accounts. A
normal user may only change the password for their own account, but
administrators may change passwords on any account.
passwd also changes account information, such as
password expiry dates and intervals.
For password changes, the user is first prompted for their old
password, if one is present. This password is then encrypted and compared
against the stored password. The user has only one chance to enter the
correct password. The administrators are permitted to bypass this step so
that forgotten passwords may be changed.
The user is then prompted for a replacement password.
passwd will prompt twice for this replacement and
compare the second entry against the first. Both entries are required to
match in order for the password to be changed.
After the password has been entered, password aging information is
checked to see if the user is permitted to change their password at this
time. If not, passwd refuses to change the password
and exits.
To get current password status information, use the
-S option. Administrators can use
passwd to perform several account maintenance
functions (users may perform some of these functions on their own
accounts). Accounts may be locked with the -l flag and
unlocked with the -u flag. Similarly,
-c disables a user's ability to change passwords, and
-C allows a user to change passwords. For password
expiry, the -e option disables expiration, while the
-E option causes the password to expire according to
the system's normal aging rules. Use -p to disable the
password requirement for a user, or -P to require a
password.
Administrators can also use passwd to change
system-wide password expiry and length requirements with the
-i, -n, -x, and
-L options. The -i option is used
to disable an account after the password has been expired for a number of
days. After a user account has had an expired password for
NUM days, the user may no longer sign on to the
account. The -n option is used to set the minimum
number of days before a password may be changed. The user will not be
permitted to change the password until MINDAYS days
have elapsed. The -x option is used to set the maximum
number of days a password remains valid. After
MAXDAYS days, the password is required to be
changed. Allowed values for the above options are 0 to 999. The
-L option sets the minimum length of allowed passwords
for users who don't belong to the administrators group to
LEN characters. Allowed values for the minimum
password length are 0 to 14. In any of the above cases, a value of 0
means `no restrictions'.
All operations affecting the current user are by default run against
the logon server of the current user (taken from the environment variable
LOGONSERVER. When password or account information of other
users should be changed, the logon server is evaluated automatically.
In rare cases, it might be necessary to switch to another domain
controller to perform the action. In this case, use the
-d option to specify the machine to run the command
against. Note that the current user must have account operator permissions
to perform user account changes in a domain.
Users can use the passwd -R to enter a password
which then gets stored in a special area of the registry on the local
system, which is also used by Windows to store passwords of accounts
running Windows services. When a privileged Cygwin application calls the
set{e}uid(user_id) system call, Cygwin checks if a
password for that user has been stored in this registry area. If so, it
uses this password to switch to this user account using that password.
This allows you to logon through, for instance, ssh
with public key authentication and get a full qualified user token with
all credentials for network access. However, the method has some
drawbacks security-wise. This is explained in more detail in .
Please note that storing passwords in that registry area is a
privileged operation which only administrative accounts are allowed to
do. Administrators can enter the password for other user accounts into
the registry by specifying the username on the commandline. If normal,
non-admin users should be allowed to enter their passwords using
passwd -R, it's required to run
cygserver as a service under the LocalSystem account
before running passwd -R. This only affects storing
passwords. Using passwords in privileged processes does not require
cygserver to run.
Limitations: Users may not be able to change their password on some
systems.
pldd
1
Cygwin Utilities
pldd
List dynamic shared objects loaded into a process
pldd [OPTION...] PID
Options
-?, --help Give this help list
--usage Give a short usage message
-V, --version Print program version
Description
pldd prints the shared libraries (DLLs) loaded by
the process with the given PID.
ps
1
Cygwin Utilities
ps
Report process status
ps [-aefls] [-u UID]
Options
-a, --all show processes of all users
-e, --everyone show processes of all users
-f, --full show process uids, ppids
-h, --help output usage information and exit
-l, --long show process uids, ppids, pgids, winpids
-p, --process show information for specified PID
-s, --summary show process summary
-u, --user list processes owned by UID
-V, --version output version information and exit
-W, --windows show windows as well as cygwin processes
With no options, ps outputs the long format by default
Description
The ps program gives the status of all the Cygwin
processes running on the system (ps = "process status"). Due to the
limitations of simulating a POSIX environment under Windows, there is
little information to give.
The PID column is the process ID you need to give to the
kill command. The PPID is the parent process ID, and
PGID is the process group ID. The WINPID column is the process ID
displayed by NT's Task Manager program. The TTY column gives which
pseudo-terminal a process is running on, or a '?' for
services. The UID column shows which user owns each process. STIME is the
time the process was started, and COMMAND gives the name of the program
running. Listings may also have a status flag in column zero;
S means stopped or suspended (in other words, in the
background), I means waiting for input or interactive
(foreground), and O means waiting to output.
By default, ps will only show processes owned by
the current user. With either the -a or
-e option, all user's processes (and system processes)
are listed. There are historical UNIX reasons for the synonomous options,
which are functionally identical. The -f option
outputs a "full" listing with usernames for UIDs. The
-l option is the default display mode, showing a
"long" listing with all the above columns. The other display option is
-s, which outputs a shorter listing of just PID, TTY,
STIME, and COMMAND. The -u option allows you to show
only processes owned by a specific user. The -p option
allows you to show information for only the process with the specified
PID. The -W option causes ps show
non-Cygwin Windows processes as well as Cygwin processes. The WINPID is
also the PID, and they can be killed with the Cygwin
kill command's -f option.
regtool
1
Cygwin Utilities
regtool
View or edit the Windows registry
regtool [OPTION] (add|check|get|list|remove|unset|load|unload|save) KEY
Options
Actions:
add KEY\SUBKEY add new SUBKEY
check KEY exit 0 if KEY exists, 1 if not
get KEY\VALUE prints VALUE to stdout
list KEY list SUBKEYs and VALUEs
remove KEY remove KEY
set KEY\VALUE [data ...] set VALUE
unset KEY\VALUE removes VALUE from KEY
load KEY\SUBKEY PATH load hive from PATH into new SUBKEY
unload KEY\SUBKEY unload hive and remove SUBKEY
save KEY\SUBKEY PATH save SUBKEY into new file PATH
restore KEY\SUBKEY PATH restore SUBKEY from file PATH
Options for 'list' Action:
-k, --keys print only KEYs
-l, --list print only VALUEs
-p, --postfix like ls -p, appends '\' postfix to KEY names
Options for 'get' Action:
-b, --binary print REG_BINARY data as hex bytes
-n, --none print data as stream of bytes as stored in registry
-x, --hex print numerical data as hex numbers
Options for 'set' Action:
-b, --binary set type to REG_BINARY (hex args or '-')
-D, --dword-be set type to REG_DWORD_BIG_ENDIAN
-e, --expand-string set type to REG_EXPAND_SZ
-i, --integer set type to REG_DWORD
-m, --multi-string set type to REG_MULTI_SZ
-n, --none set type to REG_NONE
-Q, --qword set type to REG_QWORD
-s, --string set type to REG_SZ
Options for 'set' and 'unset' Actions:
-K<c>, --key-separator[=]<c> set key separator to <c> instead of '\'
Options for 'restore' action:
-f, --force restore even if open handles exist at or beneath the location
in the registry hierarchy to which KEY\SUBKEY points
Other Options:
-h, --help output usage information and exit
-q, --quiet no error output, just nonzero return if KEY/VALUE missing
-v, --verbose verbose output, including VALUE contents when applicable
-w, --wow64 access 64 bit registry view (ignored on 32 bit Windows)
-W, --wow32 access 32 bit registry view (ignored on 32 bit Windows)
-V, --version output version information and exit
KEY is in the format [host]\prefix\KEY\KEY\VALUE, where host is optional
remote host in either \\hostname or hostname: format and prefix is any of:
root HKCR HKEY_CLASSES_ROOT (local only)
config HKCC HKEY_CURRENT_CONFIG (local only)
user HKCU HKEY_CURRENT_USER (local only)
machine HKLM HKEY_LOCAL_MACHINE
users HKU HKEY_USERS
You can use forward slash ('/') as a separator instead of backslash, in
that case backslash is treated as an escape character.
You can also supply the registry path prefix /proc/registry{,32,64}/ to
use path completion.
Example:
regtool list '/HKLM/SOFTWARE/Classes/MIME/Database/Content Type/audio\\/wav'
Description
The regtool program allows shell scripts to access
and modify the Windows registry. Note that modifying the Windows registry
is dangerous, and carelessness here can result in an unusable system. Be
careful.
The -v option means "verbose". For most commands,
this causes additional or lengthier messages to be printed. Conversely,
the -q option supresses error messages, so you can use
the exit status of the program to detect if a key exists or not (for
example).
The -w option allows you to access the 64 bit view
of the registry. Several subkeys exist in a 32 bit and a 64 bit version
when running on Windows 64. Since Cygwin is running in 32 bit mode, it
only has access to the 32 bit view of these registry keys. When using the
-w switch, the 64 bit view is used and
regtool can access the entire registry. This option is
simply ignored when running on 32 bit Windows versions.
The -W option allows you to access the 32 bit view
on the registry. The purpose of this option is mainly for symmetry. It
permits creation of OS agnostic scripts which would also work in a
hypothetical 64 bit version of Cygwin.
You must provide regtool with an
action following options (if any). Currently, the
action must be add, set,
check, get,
list, remove,
set, or unset.
The add action adds a new key. The
check action checks to see if a key exists (the exit
code of the program is zero if it does, nonzero if it does not). The
get action gets the value of a key, and prints it (and
nothing else) to stdout. Note: if the value doesn't exist, an error
message is printed and the program returns a non-zero exit code. If you
give -q, it doesn't print the message but does return
the non-zero exit code.
The list action lists the subkeys and values
belonging to the given key. With list, the
-k option instructs regtool to
print only KEYs, and the -l option to print only
VALUEs. The -p option postfixes a
'/' to each KEY, but leave VALUEs with no postfix. The
remove action removes a key. Note that you may need to
remove everything in the key before you may remove it, but don't rely on
this stopping you from accidentally removing too much.
The get action prints a value within a key. With
the -b option, data is printed as hex bytes.
-n allows to print the data as a typeless stream of
bytes. Integer values (REG_DWORD, REG_QWORD) are usually printed as
decimal values. The -x option allows to print the
numbers as hexadecimal values.
The set action sets a value within a key.
-b means it's binary data (REG_BINARY). The binary
values are specified as hex bytes in the argument list. If the argument
is '-', binary data is read from stdin instead.
-d or -i means the value is a 32
bit integer value (REG_DWORD). -D means the value is a
32 bit integer value in Big Endian representation (REG_DWORD_BIG_ENDIAN).
-Q means the value is a 64 bit integer value
(REG_QWORD). -s means the value is a string (REG_SZ).
-e means it's an expanding string (REG_EXPAND_SZ) that
contains embedded environment variables. -m means it's
a multi-string (REG_MULTI_SZ). If you don't specify one of these,
regtool tries to guess the type based on the value you
give. If it looks like a number, it's a DWORD, unless it's value doesn't
fit into 32 bit, in which case it's a QWORD. If it starts with a percent,
it's an expanding string. If you give multiple values, it's a
multi-string. Else, it's a regular string.
The unset action removes a value from a
key.
The load action adds a new subkey and loads the
contents of a registry hive into it. The parent key must be
HKEY_LOCAL_MACHINE or HKEY_USERS. The unload action
unloads the file and removes the subkey.
The save action saves a subkey into a registry
file. Ideally you append the suffix .reg to the file
so it gets automatically recognized as registry file by
Windows Explorer.
The restore action restores a registry subkey
from a file saved via the aforementioned save action.
By default, the last "\" or "/" is assumed to be the separator
between the key and the value. You can use the -K
option to provide an alternate key/value separator character.
setfacl
1
Cygwin Utilities
setfacl
Modify file and directory access control lists (ACLs)
setfacl [-n] {-f ACL_FILE | -s acl_entries} FILE...
setfacl [-n] {[-bk]|[-x acl_entries] [-m acl_entries]} FILE...
Options
-b, --remove-all remove all extended ACL entries\n"
-x, --delete delete one or more specified ACL entries\n"
-f, --set-file set ACL entries for FILE to ACL entries read\n"
from ACL_FILE\n"
-k, --remove-default remove all default ACL entries\n"
-m, --modify modify one or more specified ACL entries\n"
-n, --no-mask don't recalculate the effective rights mask\n"
--mask do recalculate the effective rights mask\n"
-s, --set set specified ACL entries on FILE\n"
-V, --version print version and exit\n"
-h, --help this help text\n"
At least one of (-b, -x, -f, -k, -m, -s) must be specified\n"
Description
For each file given as parameter, setfacl will
either replace its complete ACL (-s,
-f), or it will add, modify, or delete ACL entries.
For more information on Cygwin and Windows ACLs, see
in the Cygwin User's Guide.
Acl_entries are one or more comma-separated ACL entries from the
following list:
u[ser]::perm
u[ser]:uid:perm
g[roup]::perm
g[roup]:gid:perm
m[ask]::perm
o[ther]::perm
Default entries are like the above with the additional default
identifier. For example:
d[efault]:u[ser]:uid:perm
perm is either a 3-char permissions string in
the form "rwx" with the character '-' for no
permission or it is the octal representation of the permissions, a value
from 0 (equivalent to "---") to 7 ("rwx"). uid is a
user name or a numerical uid. gid is a group name or
a numerical gid.
The following options are supported:
-b,--remove-all Remove all
extended ACL entries. The base ACL entries of the owner, group and
others are retained. This option can be combined with the
-k,--remove-default option
to delete all non-standard POSIX permissions.
-x,--delete Delete one or
more specified entries from the file's ACL. The owner, group and others
entries must not be deleted. Acl_entries to be deleted should be
specified without permissions, as in the following list:
u[ser]:uid[:]
g[roup]:gid[:]
m[ask][:]
d[efault]:u[ser][:uid]
d[efault]:g[roup][:gid]
d[efault]:m[ask][:]
d[efault]:o[ther][:]
-f,--set-file Take the Acl_entries
from ACL_FILE one per line. Whitespace characters are ignored, and the
character "#" may be used to start a comment. The special filename "-"
indicates reading from stdin. Note that you can use this with
getfacl and setfacl to copy ACLs
from one file to another:
$ getfacl source_file | setfacl -f - target_file
Required entries are: one user entry for the owner of the file, one
group entry for the group of the file, and one other entry.
If additional user and group entries are given: a mask entry for the
file group class of the file, and no duplicate user or group entries with
the same uid/gid.
If it is a directory: one default user entry for the owner of the
file, one default group entry for the group of the file, one default mask
entry for the file group class, and one default other entry.
-k,--remove-default Remove all
default ACL entries. If no default ACL entries exist, no warnings are
issued. This option can be combined with the
-b,--remove-all option
to delete all non-standard POSIX permissions.
-m,--modify Add or modify one
or more specified ACL entries. Acl_entries is a comma-separated list of
entries from the same list as above.
-n,--no-mask Valid in
conjunction with -m. Do not recalculate the effective rights mask.
The default behavior of setfacl is to recalculate the ACL mask entry,
unless a mask entry was explicitly given. The mask entry is set to
the union of all permissions of the owning group, and all named user
and group entries. (These are exactly the entries affected by the
mask entry).
--mask Valid in conjunction with -m. Do
recalculate the effective rights mask, even if an ACL mask entry was
explicitly given. (See the -n option.)
-s,--set Like
-f, but set the file's ACL with Acl_entries
specified in a comma-separated list on the command line.
While the -x and -m options
may be used in the same command, the -f and
-s options may be used only exclusively.
Directories may contain default ACL entries. Files created in a
directory that contains default ACL entries will have permissions
according to the combination of the current umask, the explicit
permissions requested and the default ACL entries.
setmetamode
1
Cygwin Utilities
setmetamode
Get or set keyboard meta mode
setmetamode [metabit|escprefix]
Options
Without argument, it shows the current meta key mode.
metabit|meta|bit The meta key sets the top bit of the character.
escprefix|esc|prefix The meta key sends an escape prefix.
Other options:
-h, --help This text
-V, --version Print program version and exit
Description
setmetamode can be used to determine and set the
key code sent by the meta (aka Alt) key.
ssp
1
Cygwin Utilities
ssp
Single-step profile COMMAND
ssp [options] low_pc high_pc command...
Options
-c, --console-trace trace every EIP value to the console. *Lots* slower.
-d, --disable disable single-stepping by default; use
OutputDebugString ("ssp on") to enable stepping
-e, --enable enable single-stepping by default; use
OutputDebugString ("ssp off") to disable stepping
-h, --help output usage information and exit
-l, --dll enable dll profiling. A chart of relative DLL usage
is produced after the run.
-s, --sub-threads trace sub-threads too. Dangerous if you have
race conditions.
-t, --trace-eip trace every EIP value to a file TRACE.SSP. This
gets big *fast*.
-v, --verbose output verbose messages about debug events.
-V, --version output version information and exit
Example: ssp 0x401000 0x403000 hello.exe
Description
SSP - The Single Step Profiler
Original Author: DJ Delorie
The SSP is a program that uses the Win32 debug API to run a program
one ASM instruction at a time. It records the location of each
instruction used, how many times that instruction is used, and all
function calls. The results are saved in a format that is usable by the
profiling program gprof, although
gprof will claim the values are seconds, they really
are instruction counts. More on that later.
Because the SSP was originally designed to profile the Cygwin DLL,
it does not automatically select a block of code to report statistics on.
You must specify the range of memory addresses to keep track of manually,
but it's not hard to figure out what to specify. Use the "objdump"
program to determine the bounds of the target's ".text" section. Let's
say we're profiling cygwin1.dll. Make sure you've built it with debug
symbols (else gprof won't run) and run objdump like
this:
$ objdump -h cygwin1.dll
It will print a report
like this:
cygwin1.dll: file format pei-i386
Sections:
Idx Name Size VMA LMA File off Algn
0 .text 0007ea00 61001000 61001000 00000400 2**2
CONTENTS, ALLOC, LOAD, READONLY, CODE, DATA
1 .data 00008000 61080000 61080000 0007ee00 2**2
CONTENTS, ALLOC, LOAD, DATA
. . .
The only information we're concerned with are the VMA of the .text
section and the VMA of the section after it (sections are usually
contiguous; you can also add the Size to the VMA to get the end address).
In this case, the VMA is 0x61001000 and the ending address is either
0x61080000 (start of .data method) or 0x0x6107fa00 (VMA+Size method).
There are two basic ways to use SSP - either profiling a whole
program, or selectively profiling parts of the program.
To profile a whole program, just run ssp without
options. By default, it will step the whole program. Here's a simple
example, using the numbers above:
$ ssp 0x61001000 0x61080000 hello.exe
This will step
the whole program. It will take at least 8 minutes on a PII/300 (yes,
really). When it's done, it will create a file called "gmon.out". You can
turn this data file into a readable report with gprof:
$ gprof -b cygwin1.dll
The "-b" means 'skip the help
pages'. You can omit this until you're familiar with the report layout.
The gprof documentation explains a lot about this
report, but ssp changes a few things. For example, the
first part of the report reports the amount of time spent in each
function, like this:
Each sample counts as 0.01 seconds.
% cumulative self self total
time seconds seconds calls ms/call ms/call name
10.02 231.22 72.43 46 1574.57 1574.57 strcspn
7.95 288.70 57.48 130 442.15 442.15 strncasematch
The "seconds" columns are really CPU opcodes, 1/100 second per opcode.
So, "231.22" above means 23,122 opcodes. The ms/call values are 10x too
big; 1574.57 means 157.457 opcodes per call. Similar adjustments need to
be made for the "self" and "children" columns in the second part of the
report.
OK, so now we've got a huge report that took a long time to
generate, and we've identified a spot we want to work on optimizing.
Let's say it's the time() function. We can use SSP to selectively profile
this function by using OutputDebugString() to control SSP from within the
program. Here's a sample program:
#include <windows.h>
main()
{
time_t t;
OutputDebugString("ssp on");
time(&t);
OutputDebugString("ssp off");
}
Then, add the -d option to ssp to default to
*disabling* profiling. The program will run at full speed until the first
OutputDebugString, then step until the second. You can then use
gprof (as usual) to see the performance profile for
just that portion of the program's execution.
There are many options to ssp. Since step-profiling makes your
program run about 1,000 times slower than normal, it's best to understand
all the options so that you can narrow down the parts of your program you
need to single-step.
-v - verbose. This prints messages about threads
starting and stopping, OutputDebugString calls, DLLs loading, etc.
-t and -c - tracing. With
-t, *every* step's address is written to the file
"trace.ssp". This can be used to help debug functions, since it can trace
multiple threads. Clever use of scripts can match addresses with
disassembled opcodes if needed. Warning: creates *huge* files, very
quickly. -c prints each address to the console, useful
for debugging key chunks of assembler. Use addr2line -C -f -s -e
foo.exe < trace.ssp > lines.ssp and then perl
cvttrace to convert to symbolic traces.
-s - subthreads. Usually, you only need to trace
the main thread, but sometimes you need to trace all threads, so this
enables that. It's also needed when you want to profile a function that
only a subthread calls. However, using OutputDebugString automatically
enables profiling on the thread that called it, not the main thread.
-l - dll profiling. Generates a pretty table of
how much time was spent in each dll the program used. No sense optimizing
a function in your program if most of the time is spent in the DLL. I
usually use the -v, -s, and
-l options:
$ ssp -v -s -l -d 0x61001000 0x61080000 hello.exe
strace
1
Cygwin Utilities
strace
Trace system calls and signals
strace [OPTIONS] <command-line>
strace [OPTIONS] -p <pid>
Options
-b, --buffer-size=SIZE set size of output file buffer
-d, --no-delta don't display the delta-t microsecond timestamp
-e, --events log all Windows DEBUG_EVENTS (toggle - default true)
-f, --trace-children trace child processes (toggle - default true)
-h, --help output usage information and exit
-m, --mask=MASK set message filter mask
-n, --crack-error-numbers output descriptive text instead of error
numbers for Windows errors
-o, --output=FILENAME set output file to FILENAME
-p, --pid=n attach to executing program with cygwin pid n
-q, --quiet toggle "quiet" flag. Defaults to on if "-p",
off otherwise.
-S, --flush-period=PERIOD flush buffered strace output every PERIOD secs
-t, --timestamp use an absolute hh:mm:ss timestamp insted of
the default microsecond timestamp. Implies -d
-T, --toggle toggle tracing in a process already being
traced. Requires -p <pid>
-u, --usecs toggle printing of microseconds timestamp
-V, --version output version information and exit
-w, --new-window spawn program under test in a new window
MASK can be any combination of the following mnemonics and/or hex values
(0x is optional). Combine masks with '+' or ',' like so:
--mask=wm+system,malloc+0x00800
Mnemonic Hex Corresponding Def Description
=========================================================================
all 0x000001 (_STRACE_ALL) All strace messages.
flush 0x000002 (_STRACE_FLUSH) Flush output buffer after each message.
inherit 0x000004 (_STRACE_INHERIT) Children inherit mask from parent.
uhoh 0x000008 (_STRACE_UHOH) Unusual or weird phenomenon.
syscall 0x000010 (_STRACE_SYSCALL) System calls.
startup 0x000020 (_STRACE_STARTUP) argc/envp printout at startup.
debug 0x000040 (_STRACE_DEBUG) Info to help debugging.
paranoid 0x000080 (_STRACE_PARANOID) Paranoid info.
termios 0x000100 (_STRACE_TERMIOS) Info for debugging termios stuff.
select 0x000200 (_STRACE_SELECT) Info on ugly select internals.
wm 0x000400 (_STRACE_WM) Trace Windows msgs (enable _strace_wm).
sigp 0x000800 (_STRACE_SIGP) Trace signal and process handling.
minimal 0x001000 (_STRACE_MINIMAL) Very minimal strace output.
pthread 0x002000 (_STRACE_PTHREAD) Pthread calls.
exitdump 0x004000 (_STRACE_EXITDUMP) Dump strace cache on exit.
system 0x008000 (_STRACE_SYSTEM) Serious error; goes to console and log.
nomutex 0x010000 (_STRACE_NOMUTEX) Don't use mutex for synchronization.
malloc 0x020000 (_STRACE_MALLOC) Trace malloc calls.
thread 0x040000 (_STRACE_THREAD) Thread-locking calls.
special 0x100000 (_STRACE_SPECIAL) Special debugging printfs for
non-checked-in code
Description
The strace program executes a program, and
optionally the children of the program, reporting any Cygwin DLL output
from the program(s) to stdout, or to a file with the
-o option. With the -w option, you
can start an strace session in a new window, for example:
$ strace -o tracing_output -w sh -c 'while true; do echo "tracing..."; done' &
This is particularly useful for strace sessions that
take a long time to complete.
Note that strace is a standalone Windows program
and so does not rely on the Cygwin DLL itself (you can verify this with
cygcheck). As a result it does not understand
symlinks. This program is mainly useful for debugging the Cygwin DLL
itself.
tzset
1
Cygwin Utilities
tzset
Print POSIX-compatible timezone ID from current Windows timezone setting
tzset [OPTION]
Options
Options:
-h, --help output usage information and exit.
-V, --version output version information and exit.
Description
Use tzset to set your TZ variable. In POSIX-compatible shells like bash,
dash, mksh, or zsh:
export TZ=$(tzset)
In csh-compatible shells like tcsh:
setenv TZ `tzset`
The tzset tool reads the current timezone from
Windows and generates a POSIX-compatible timezone information for the TZ
environment variable from that information. That's all there is to it.
For the way how to use it, see the above usage information.
umount
1
Cygwin Utilities
umount
Unmount filesystems
umount [OPTION] [<posixpath>]
Options
-h, --help output usage information and exit
-U, --remove-user-mounts remove all user mounts
-V, --version output version information and exit
Description
The umount program removes mounts from the mount
table in the current session. If you specify a POSIX path that
corresponds to a current mount point, umount will
remove it from the current mount table. Note that you can only remove
user mount points. The -U flag may be used to specify
removing all user mount points from the current user session.
See for more information on the mount
table.