1096 lines
46 KiB
XML
1096 lines
46 KiB
XML
<!-- faq-problems.xml -->
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<qandaentry id="faq.using.missing-dlls">
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<question><para>Why can't my application locate cygncurses-8.dll? or cygintl-3.dll? or cygreadline6.dll? or ...?</para></question>
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<answer>
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<para>Well, something has gone wrong somehow...
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</para>
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<para>To repair the damage, you must run Cygwin Setup again, and re-install the
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package which provides the missing DLL package.
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</para>
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<para>If you already installed the package at one point, Cygwin Setup won't
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show the option to install the package by default. In the
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``Select packages to install'' dialog, click on the <literal>Full/Part</literal>
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button. This lists all packages, even those that are already
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installed. Scroll down to locate the missing package, for instance
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<literal>libncurses8</literal>. Click on the ``cycle'' glyph until it says
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``Reinstall''. Continue with the installation.
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</para>
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<para>For a detailed explanation of the general problem, and how to extend
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it to other missing DLLs and identify their containing packages, see
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<ulink url="http://cygwin.com/ml/cygwin/2002-01/msg01619.html">http://cygwin.com/ml/cygwin/2002-01/msg01619.html</ulink>.
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</para>
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</answer></qandaentry>
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<qandaentry id="faq.using.slow">
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<question><para>Why is Cygwin suddenly <emphasis>so</emphasis> slow?</para></question>
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<answer>
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<para>If suddenly <emphasis>every</emphasis> command takes a
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<emphasis>very</emphasis> long time, then something is probably attempting to
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access a network share. You may have the obsolete <literal>//c</literal>
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notation in your PATH or startup files. Using <literal>//c</literal> means
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to contact the <emphasis>network server</emphasis> <literal>c</literal>, which
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will slow things down tremendously if it does not exist.
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</para>
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<para>Using //c (for C:) doesn't work. (Similarly for any drive
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letter, e.g. <literal>//z</literal> for <literal>Z:</literal>) This
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``feature'' has long been deprecated.
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For a detailed discussion of why this change was made, and how deal
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with it, refer to
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<ulink url="http://sources.redhat.com/ml/cygwin/2001-09/msg00014.html">http://sources.redhat.com/ml/cygwin/2001-09/msg00014.html</ulink>.
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Just note that, in contrast to what that posting claims, using
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<literal>/</literal> as the cygdrive prefix is not supported anymore for a
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long time (though it still might work).
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</para>
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</answer></qandaentry>
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<qandaentry id="faq.using.shares">
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<question><para>Why can't my services access network shares?</para></question>
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<answer>
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<para>If your service is one of those which switch the user context
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(sshd, inetd, etc), then it depends on the method used to switch to
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another user. This problem as well as its solution is described in
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detail in the Cygwin User's Guide, see
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<ulink url="http://cygwin.com/cygwin-ug-net/ntsec.html" />.
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</para>
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<para>Workarounds include using public network share that does not require
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authentication (for non-critical files), providing your password to a
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<command>net use</command> command, or running the service as your own
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user with <literal>cygrunsrv -u</literal> (see
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<literal>/usr/share/doc/Cygwin/cygrunsrv.README</literal> for more
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information).
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</para>
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</answer></qandaentry>
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<qandaentry id="faq.using.path">
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<question><para>How should I set my PATH?</para></question>
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<answer>
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<para>This is done for you in the file /etc/profile, which is sourced by bash
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when you start it from the Desktop or Start Menu shortcut, created by
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<literal>setup.exe</literal>. The line is
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</para>
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<screen>
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PATH="/usr/local/bin:/usr/bin:/bin:$PATH"
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</screen>
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<para>Effectively, this <emphasis role='bold'>prepends</emphasis> /usr/local/bin and /usr/bin to your
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Windows system path. If you choose to reset your PATH, say in
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$HOME/.bashrc, or by editing etc/profile directly, then you should
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follow this rule. You <emphasis role='bold'>must</emphasis> have <literal>/usr/bin</literal> in your PATH
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<emphasis role='bold'>before</emphasis> any Windows system directories. (And you must not omit
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the Windows system directories!) Otherwise you will likely encounter
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all sorts of problems running Cygwin applications.
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</para>
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<para>If you're using another shell than bash (say, tcsh), the mechanism
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is the same, just the names of the login scripts are different.
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</para>
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</answer></qandaentry>
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<qandaentry id="faq.using.not-found">
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<question><para>Bash (or another shell) says "command not found", but it's right there!</para></question>
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<answer>
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<para>If you compile a program, you might find that you can't run it:
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</para>
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<screen>
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bash$ gcc -o hello hello.c
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bash$ hello
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bash: hello: command not found
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</screen>
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<para>Unlike the Windows default behaviour, Unix shells like bash do not look for programs in <literal>.</literal> (the current
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directory) by default. You can add <literal>.</literal> to your PATH (see above),
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but this is not recommended (at least on UNIX) for security reasons.
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Just tell bash where to find it, when you type it on the command line:
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</para>
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<screen>
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bash$ gcc -o hello hello.c
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bash$ ./hello
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Hello World!
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</screen>
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</answer></qandaentry>
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<qandaentry id="faq.using.converting-paths">
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<question><para>How do I convert between Windows and UNIX paths?</para></question>
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<answer>
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<para>Use the 'cygpath' utility. Type '<literal>cygpath --help</literal>' for
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information. For example (on my installation):
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<screen>
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bash$ cygpath --windows ~/.bashrc
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D:\starksb\.bashrc
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bash$ cygpath --unix C:/cygwin/bin/cygwin.bat
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/usr/bin/cygwin.bat
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bash$ cygpath --unix C:\\cygwin\\bin\\cygwin.bat
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/usr/bin/cygwin.bat
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</screen>
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Note that bash interprets the backslash '\' as an escape character, so
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you must type it twice in the bash shell if you want it to be recognized
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as such.
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</para>
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</answer></qandaentry>
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<qandaentry id="faq.using.bashrc">
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<question><para>Why doesn't bash read my .bashrc file on startup?</para></question>
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<answer>
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<para>Your .bashrc is read from your home directory specified by the HOME
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environment variable. It uses /.bashrc if HOME is not set. So you need
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to set HOME (and the home dir in your /etc/passwd entry) correctly.
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</para>
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</answer></qandaentry>
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<qandaentry id="faq.using.bash-insensitive">
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<question><para>How can I get bash filename completion to be case insensitive?</para></question>
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<answer>
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<para>Add the following to your <literal>~/.bashrc</literal> file:
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</para>
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<screen>
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shopt -s nocaseglob
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</screen>
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<para>and add the following to your <literal>~/.inputrc</literal> file:
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</para>
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<screen>
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set completion-ignore-case on
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</screen>
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</answer></qandaentry>
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<qandaentry id="faq.using.filename-spaces">
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<question><para>Can I use paths/filenames containing spaces in them?</para></question>
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<answer>
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<para>Cygwin does support spaces in filenames and paths. That said, some
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utilities that use the library may not, since files don't typically
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contain spaces in Unix. If you stumble into problems with this, you
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will need to either fix the utilities or stop using spaces in filenames
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used by Cygwin tools.
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</para>
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<para>In particular, bash interprets space as a word separator. You would have
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to quote a filename containing spaces, or escape the space character.
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For example:
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<screen>
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bash-2.03$ cd '/cygdrive/c/Program Files'
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</screen>
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or
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<screen>
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bash-2.03$ cd /cygdrive/c/Program\ Files
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</screen>
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</para>
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</answer></qandaentry>
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<qandaentry id="faq.using.shortcuts">
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<question><para>Why can't I cd into a shortcut to a directory?</para></question>
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<answer>
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<para>Cygwin does not follow MS Windows Explorer Shortcuts
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(*.lnk files). It sees a shortcut as a regular file and this you
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cannot "cd" into it.
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</para>
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<para>Cygwin is also capable to create POSIX symlinks as Windows shortcuts
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(see the CYGWIN environment variable option "winsymlinks"), but these
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shortcuts are different from shortcuts created by native Windows
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applications. Windows applications can usually make use of Cygwin
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shortcuts but not vice versa. This is by choice. The reason is that
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Windows shortcuts may contain a bunch of extra information which would
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get lost, if, for example, Cygwin tar archives and extracts them as
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symlinks.
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</para>
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<para>Changing a Cygwin shortcut in Windows Explorer usually changes a Cygwin
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shortcut into a Windows native shortcut. Afterwards, Cygwin will not
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recognize it as symlink anymore.
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</para>
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</answer></qandaentry>
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<qandaentry id="faq.using.find">
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<question><para>I'm having basic problems with find. Why?</para></question>
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<answer>
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<para>Make sure you are using the find that came with Cygwin and that you
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aren't picking up the Win32 find command instead. You can verify that
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you are getting the right one by doing a "type find" in bash.
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</para>
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<para>If the path argument to find, including current directory (default), is
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itself a symbolic link, then find will not traverse it unless you
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specify the <literal>-follow</literal> option. This behavior is different than most
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other UNIX implementations, but is not likely to change.
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</para>
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<para>If find does not seem to be producing enough results, or seems to be
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missing out some directories, you may be experiencing a problem with one
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of find's optimisations. The absence of <literal>.</literal> and <literal>..</literal>
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directories on some filesystems, such as DVD-R UDF, can confuse find.
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See the documentation for the option <literal>-noleaf</literal> in the man page.
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</para>
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</answer></qandaentry>
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<qandaentry id="faq.using.su">
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<question><para>Why doesn't <literal>su</literal> work?</para></question>
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<answer>
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<para>The <literal>su</literal> command has been in and out of Cygwin distributions, but
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it has not been ported to Cygwin and has never worked. It is
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currently installed as part of the sh-utils, but again, it does not work.
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</para>
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<para>You should rather install <literal>sshd</literal> and use
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<literal>ssh username@localhost</literal> as a <literal>su</literal>
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replacement.
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</para>
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<para>For some technical background into why <literal>su</literal> doesn't work, read
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<ulink url="http://www.cygwin.com/ml/cygwin/2003-06/msg00897.html">http://www.cygwin.com/ml/cygwin/2003-06/msg00897.html</ulink> and
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related messages.
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</para>
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</answer></qandaentry>
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<qandaentry id="faq.using.man">
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<question><para>Why doesn't man -k (or apropos) work?</para></question>
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<answer>
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<para>Before you can use <literal>man -k</literal> or <literal>apropos</literal>, you
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must create the whatis database. Just run the command
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</para>
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<screen>
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/usr/sbin/makewhatis
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</screen>
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<para>(it may take a minute to complete).
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</para>
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</answer></qandaentry>
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<qandaentry id="faq.using.chmod">
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<question><para>Why doesn't <literal>chmod</literal> work?</para></question>
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<answer>
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<para>The most common case is that your <literal>/etc/passwd</literal>
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or <literal>/etc/group</literal> files are not properly set up. If
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<literal>ls -l</literal> shows a group of <literal>mkpasswd</literal>
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or <literal>mkgroup</literal>, you need to run one or both of those
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commands.
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</para>
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<para>If you're using FAT32 instead of NTFS, <literal>chmod</literal>
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will fail since FAT32 does not provide any permission information.
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You should really consider converting the drive to NTFS with
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<literal>CONVERT.EXE</literal>. FAT and FAT32 are barely good enough
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for memory cards or USB sticks to exchange pictures...
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</para>
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<para>For other cases, understand that Cygwin attempts to show UNIX
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permissions based on the security features of Windows, so the Windows
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ACLs are likely the source of your problem. See the Cygwin User's
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Guide at <ulink url="http://cygwin.com/cygwin-ug-net/ntsec.html" />
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for more information on how Cygwin maps Windows permissions.
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</para>
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</answer></qandaentry>
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<qandaentry id="faq.using.shell-scripts">
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<question><para>Why doesn't my shell script work?</para></question>
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<answer>
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<para>There are two basic problems you might run into. One is the fact that
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<command>/bin/sh</command> is really <command>bash</command>.
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It could be missing some features you might expect in
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<command>/bin/sh</command>, if you are used to <command>/bin/sh</command>
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actually being <command>zsh</command> (MacOS X "Panther") or
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<command>ksh</command> (Tru64).
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</para>
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<para>Or, it could be a permission problem, and Cygwin doesn't understand
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that your script is executable. On NTFS or NFS just make the script
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executable using <literal>chmod +x</literal>. However,
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<literal>chmod</literal> may not work due to restrictions of the
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filesystem (see FAQ entry above). In this case Cygwin must read the
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contents of files to determine if they are executable. If your script
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does not start with
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</para>
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<screen>
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#! /bin/sh
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</screen>
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<para>(or any path to a script interpreter, it does not have to be /bin/sh)
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then Cygwin will not know it is an executable script. The Bourne shell
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idiom
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</para>
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<screen>
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:
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# This is the 2nd line, assume processing by /bin/sh
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</screen>
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<para>also works.
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</para>
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<para>Note that you can use the filesystem flag <literal>cygexec</literal> in
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<filename>/etc/fstab</filename> to force Cygwin to treat all files
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under the mount point as executable. This can be used for individual
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files as well as directories. Then Cygwin will not bother to read files
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to determine whether they are executable.
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</para>
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</answer></qandaentry>
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<qandaentry id="faq.using.printing">
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<question><para>How do I print under Cygwin?</para></question>
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<answer>
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<para>lpr is available in the <ulink url="http://cygwin.com/setup.exe">setup.exe</ulink> cygutils package. Some <ulink url="http://cygwin.com/ml/cygwin/2008-05/msg00123.html">usage hints</ulink> are available courtesy of Rodrigo Medina.
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</para>
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<para>Jason Tishler has written a couple of messages that explain how to use
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a2ps (for nicely formatted text in PostScript) and ghostscript (to print
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PostScript files on non-PostScript Windows printers). Start at
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<ulink url="http://cygwin.com/ml/cygwin/2001-04/msg00657.html">http://cygwin.com/ml/cygwin/2001-04/msg00657.html</ulink>. Note that the
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<literal>file</literal> command is now available as part of Cygwin setup.
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</para>
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<para>Alternatively, on NT, you can use the Windows <literal>print</literal>
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command. (It does not seem to be available on Win9x.) Type
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</para>
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<screen>
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bash$ print /\?
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</screen>
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<para>for usage instructions (note the <literal>?</literal> must be escaped from the
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shell).
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</para>
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<para>Finally, you can simply <literal>cat</literal> the file to the printer's share name:
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</para>
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<screen>
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bash$ cat myfile > //host/printer
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</screen>
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<para>You may need to press the formfeed button on your printer or append the
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formfeed character to your file.
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</para>
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</answer></qandaentry>
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<qandaentry id="faq.using.unicode">
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<question><para>Why don't international (Unicode) characters work?</para></question>
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<answer>
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<para>Internationalization is a complex issue. The short answer is that
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Cygwin relies on the setting of the CYGWIN environment variable as well
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as on the setting of LANG/LC_xxx environment variables.</para>
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<para>To get UTF-8 support you must set the environment variable CYGWIN
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so that it contains the substring "codepage:utf8". This is required in
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Cygwin so far to get correct translation from Windows wide character
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filenames to their UTF-8 counterpart. Applications on the other hand
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require the setting of the LANG, LC_ALL, or LC_CTYPE environment variables.
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To get UTF-8 support you can set, for instance, $LANG to "en_US.UTF-8".
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This will give you support for the UTF-8 character set. Note that the
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language part has to contain a valid language specifier, but is otherwise
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so far ignored by newlib, the underlying C library. There's no support
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for correct language-specific collation, monetary or date/time-related
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string handling. This is planned for a later release, though.</para>
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<para>To type international characters (£äö) in
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<literal>bash</literal>, add the following lines to your
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<literal>~/.inputrc</literal> file and restart <literal>bash</literal>:
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</para>
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<screen>
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set meta-flag on
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set convert-meta off
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set output-meta on
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set input-meta on
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set kanji-code sjis
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</screen>
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<para>These are options to the <literal>readline</literal> library, which
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you can read about in the <literal>bash(1)</literal> and
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<literal>readline(3)</literal> man pages. Other tools that do not use
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<literal>readline</literal> for display, such as <literal>less</literal>
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and <literal>ls</literal>, require additional settings, which could be put
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in your <literal>~/.bashrc</literal>:
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<screen>
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alias less='/bin/less -r'
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alias ls='/bin/ls -F --color=tty --show-control-chars'
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export LANG="ja_JP.SJIS"
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export OUTPUT_CHARSET="sjis"
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</screen>
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These examples use the Japanese Shift-JIS character set, obviously
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you will want to change them for your own locale.
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</para>
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</answer></qandaentry>
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|
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<qandaentry id="faq.using.multiple-copies">
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|
<question><para>Is it OK to have multiple copies of the DLL?</para></question>
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|
<answer>
|
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<para>You should only have one copy of the Cygwin DLL on your system. If you
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have multiple versions, they will conflict and cause problems.
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|
</para>
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|
<para>If you get the error "shared region is corrupted" or "shared region
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version mismatch" it means you have multiple versions of cygwin1.dll
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running at the same time which conflict with each other. This could happen,
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|
for example, if you update cygwin1.dll without exiting
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<emphasis>all</emphasis> Cygwin apps (including inetd) beforehand.
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|
</para>
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<para>The only DLL that is sanctioned by the Cygwin project is the one that
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|
you get by running <ulink url="http://cygwin.com/setup.exe">setup.exe</ulink>,
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installed in the directory controlled by this program. If you have other
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versions on your system and desire help from the cygwin project, you should
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|
delete or rename all DLLs that are not installed by
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<filename>setup.exe</filename>.
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|
</para>
|
|
<para>If you're trying to find multiple versions of the DLL that are causing
|
|
this problem, reboot first, in case DLLs still loaded in memory are the
|
|
cause. Then use the Windows System find utility to search your whole
|
|
machine, not just components in your PATH (as 'type' would do) or
|
|
cygwin-mounted filesystems (as Cygwin 'find' would do).
|
|
</para>
|
|
</answer></qandaentry>
|
|
|
|
<qandaentry id="faq.using.third-party.multiple-copies">
|
|
<question><para>
|
|
I read the above but I want to bundle Cygwin with a product, and ship it
|
|
to customer sites. How can I do this without conflicting with any
|
|
Cygwin installed by the user?
|
|
</para></question>
|
|
<answer><para>
|
|
Third party developers who wish to use Cygwin should check if
|
|
there is a version of cygwin installed and use the installed
|
|
version if it is newer, or conditionally upgrade if it is not.
|
|
(If you write a tool to make this easy, consider contributing
|
|
it for others to use)
|
|
</para></answer></qandaentry>
|
|
|
|
<qandaentry id="faq.using.bundling-cygwin">
|
|
<question><para>
|
|
Can I bundle Cygwin with my product for free?
|
|
</para></question>
|
|
<answer><para>
|
|
Only if you comply with Cygwin's <ulink
|
|
url="http://cygwin.com/license.html">license</ulink> very carefully. If you
|
|
choose to distribute cygwin1.dll, you must be willing to distribute the
|
|
exact source code used to build that copy of cygwin1.dll as per the
|
|
terms of the GPL. If you ship applications that link with cygwin1.dll,
|
|
you must either provide those applications' source code under a
|
|
GPL-compatible license, *or* purchase a cygwin license from Red Hat.
|
|
</para></answer></qandaentry>
|
|
|
|
<qandaentry id="faq.using.private-cygwin">
|
|
<question><para>
|
|
So I can't install a private version of the Cygwin DLL without
|
|
conflicting with the system cygwin?
|
|
</para></question>
|
|
<answer><para>
|
|
Actually, if you are very careful, you can have two different versions
|
|
of the Cygwin DLL installed on your system at the same time but they
|
|
must be run serially. The only exception from this rule is, if one of
|
|
the DLLs is a pre-1.7 DLL and the other is a 1.7.0 or later DLL. These
|
|
DLLs can work concurrently without knowing about each other due to
|
|
massive changes using shared resources in Cygwin 1.7. However,
|
|
processes using different DLLs will not interact with each other
|
|
correctly, so keep them separate except you really really know what
|
|
you're doing.
|
|
</para>
|
|
<para>This usage is not recommeded for novices. Only limited support will be
|
|
provided in the <ulink url="http://cygwin.com/lists.html">mailing lists</ulink>
|
|
if you run into problems.
|
|
</para></answer></qandaentry>
|
|
|
|
<qandaentry id="faq.using.older-cygwin-conflict">
|
|
<question><para>
|
|
But doesn't that mean that if some application installs an older Cygwin
|
|
DLL on top of a newer DLL, my application will break?
|
|
</para></question>
|
|
<answer><para>
|
|
It depends on what you mean by "break". If the application installs a
|
|
version of the Cygwin DLL in another location than Cygwin's /bin
|
|
directory then the rules in
|
|
<xref linkend="faq.using.third-party.multiple-copies"></xref> apply.
|
|
If the application installs an older version of the DLL in /bin then you
|
|
should complain loudly to the application provider.
|
|
</para><para>
|
|
Remember that the Cygwin DLL strives to be backwards compatible so a
|
|
newer version of the DLL should always work with older executables. So,
|
|
in general, it is always best to keep one version of the DLL on your
|
|
system and it should always be the latest version which matches your
|
|
installed distribution.
|
|
</para></answer></qandaentry>
|
|
|
|
<qandaentry id="faq.using.missing-packages">
|
|
<question><para>Why isn't package XYZ available in Cygwin?</para></question>
|
|
<answer>
|
|
|
|
<para>Probably because there is nobody willing or able to maintain it. It
|
|
takes time, and the priority for the Cygwin Team is the Cygwin package.
|
|
The rest is a volunteer effort. Want to contribute? See
|
|
<ulink url="http://cygwin.com/setup.html">http://cygwin.com/setup.html</ulink>.
|
|
</para>
|
|
</answer></qandaentry>
|
|
|
|
<qandaentry id="faq.using.old-packages">
|
|
<question><para>Why is the Cygwin package of XYZ so out of date?</para></question>
|
|
<answer>
|
|
|
|
<para>(Also: Why is the version of package XYZ older than the version that I
|
|
can download from the XYZ web site? Why is the version of package XYZ
|
|
older than the version that I installed on my linux system? Is there
|
|
something special about Cygwin which requires that only an older version
|
|
of package XYZ will work on it?)
|
|
</para>
|
|
<para>Every package in the Cygwin distribution has a maintainer who is
|
|
responsible for sending out updates of the package. This person is a
|
|
volunteer who is rarely the same person as the official developer of the
|
|
package. If you notice that a version of a package seems to be out of
|
|
date, the reason is usually pretty simple -- the person who is
|
|
maintaining the package hasn't gotten around to updating it yet. Rarely,
|
|
the newer package actually requires complex changes that the maintainer
|
|
is working out.
|
|
</para>
|
|
<para>If you urgently need an update, sending a polite message to the cygwin
|
|
mailing list pinging the maintainer is perfectly acceptable. There are
|
|
no guarantees that the maintainer will have time to update the package
|
|
or that you'll receive a response to your request, however.
|
|
</para>
|
|
<para>Remember that the operative term here is "volunteer".
|
|
</para>
|
|
</answer></qandaentry>
|
|
|
|
<qandaentry id="faq.using.accessing-drives">
|
|
<question><para>How can I access other drives?</para></question>
|
|
<answer>
|
|
|
|
<para>You have some flexibility here.
|
|
</para>
|
|
<para>Cygwin has a builtin "cygdrive prefix" for drives that are not mounted.
|
|
You can access any drive, say Z:, as '/cygdrive/z/'.
|
|
</para>
|
|
<para>In some applications (notably bash), you can use the familiar windows
|
|
<drive>:/path/, using posix forward-slashes ('/') instead of Windows
|
|
backward-slashes ('\'). (But see the warning below!) This maps in the
|
|
obvious way to the Windows path, but will be converted internally to use
|
|
the Cygwin path, following mounts (default or explicit). For example:
|
|
<screen>
|
|
bash$ cd C:/Windows
|
|
bash$ pwd
|
|
/cygdrive/c/Windows
|
|
</screen>
|
|
and
|
|
<screen>
|
|
bash$ cd C:/cygwin
|
|
bash$ pwd
|
|
/
|
|
</screen>
|
|
for a default setup. You could also use backward-slashes in the
|
|
Windows path, but these would have to be escaped from the shell.
|
|
</para>
|
|
<para><emphasis role='bold'>Warning:</emphasis> There is some ambiguity in going from a Windows path
|
|
to the posix path, because different posix paths, through different
|
|
mount points, could map to the same Windows directory. This matters
|
|
because different mount points may be binmode or textmode, so the
|
|
behavior of Cygwin apps will vary depending on the posix path used to
|
|
get there.
|
|
</para>
|
|
<para>You can avoid the ambiguity of Windows paths, and avoid typing
|
|
"/cygdrive", by explicitly mounting drives to posix paths. For example:
|
|
<screen>
|
|
bash$ mkdir /c
|
|
bash$ mount c:/ /c
|
|
bash$ ls /c
|
|
</screen>
|
|
Then <literal>/cygdrive/c/Windows</literal> becomes <literal>/c/Windows</literal> which is a
|
|
little less typing.
|
|
</para>
|
|
<para>Note that you have to enter the mount point into the
|
|
<filename>/etc/fstab</filename> file to keep it indefinitely.
|
|
The mount command will only add the mount point for the lifetime
|
|
of your current Cygwin session.
|
|
</para>
|
|
<para>You can change the default <literal>cygdrive</literal> prefix and whether it is binmode or textmode using the <filename>/etc/fstab</filename> file
|
|
as well. See the Cygwin User's Guide at
|
|
<ulink url="http://cygwin.com/cygwin-ug-net/using.html#mount-table">http://cygwin.com/cygwin-ug-net/using.html#mount-table</ulink>
|
|
for more details.
|
|
</para>
|
|
</answer></qandaentry>
|
|
|
|
<qandaentry id="faq.using.copy-and-paste">
|
|
<question><para>How can I copy and paste into Cygwin console windows?</para></question>
|
|
<answer>
|
|
|
|
<para>First, consider using rxvt or mintty instead of the standard console
|
|
window. In rxvt/mintty, selecting with the left-mouse also copies,
|
|
and middle-mouse pastes. It couldn't be easier!
|
|
</para>
|
|
<para>In Windows's console window, open the properties dialog.
|
|
The options contain a toggle button, named "Quick edit mode". It must
|
|
be ON. Save the properties.
|
|
</para>
|
|
<para>You can also bind the insert key to paste from the clipboard by adding
|
|
the following line to your .inputrc file:
|
|
<screen>
|
|
"\e[2~": paste-from-clipboard
|
|
</screen>
|
|
</para>
|
|
</answer></qandaentry>
|
|
|
|
<qandaentry id="faq.using.firewall">
|
|
<question><para>What firewall should I use with Cygwin? </para></question>
|
|
<answer>
|
|
|
|
<para>We have had good reports about Kerio Personal Firewall, ZoneLabs
|
|
Integrity Desktop, and the built-in firewall in Windows XP. Other
|
|
well-known products including ZoneAlarm and Norton Internet Security have
|
|
caused problems for some users but work fine for others. At last report,
|
|
Agnitum Outpost did not work with Cygwin. If you are having strange
|
|
connection-related problems, disabling the firewall is a good
|
|
troubleshooting step (as is closing or disabling all other running
|
|
applications, especially resource-intensive processes such as indexed
|
|
search).
|
|
</para>
|
|
<para>On the whole, Cygwin doesn't care which firewall is used. The few rare
|
|
exceptions have to do with socket code.
|
|
Cygwin uses sockets to implement many of its functions, such as IPC.
|
|
Some overzealous firewalls install themselves deeply into the winsock
|
|
stack (with the 'layered service provider' API) and install hooks
|
|
throughout. Sadly the mailing list archives are littered with examples
|
|
of poorly written firewall-type software that causes things to break.
|
|
Note that with many of these products, simply disabling the firewall
|
|
does not remove these changes; it must be completely uninstalled.
|
|
</para>
|
|
<para>See also <ulink url="http://cygwin.com/faq/faq.using.html#faq.using.bloda" />
|
|
for a list of applications that have been known, at one time or another, to
|
|
interfere with the normal functioning of Cygwin.
|
|
</para>
|
|
</answer></qandaentry>
|
|
|
|
<qandaentry id="faq.using.sharing-files">
|
|
<question><para>How can I share files between Unix and Windows?</para></question>
|
|
<answer>
|
|
|
|
<para>During development, we have Linux boxes running Samba and NFS as well
|
|
as Windows machines. We often build with cross-compilers under Linux and copy
|
|
binaries and source to the Windows system or just toy with them
|
|
directly off the Samba-mounted partition. Or, we use the Microsoft NFS
|
|
client and just use NFS shares on Linux from Windows. And then there are
|
|
tools like <literal>scp</literal>, <literal>ftp</literal>,
|
|
<literal>rsync</literal>, ...
|
|
</para>
|
|
</answer></qandaentry>
|
|
|
|
<qandaentry id="faq.using.case-sensitive">
|
|
<question><para>Is Cygwin case-sensitive??</para></question>
|
|
<answer>
|
|
|
|
<para>Several Unix programs expect to be able to use to filenames
|
|
spelled the same way, but with different case. A prime example
|
|
of this is perl's configuration script, which wants
|
|
<literal>Makefile</literal> and <literal>makefile</literal>. Windows can't
|
|
tell the difference between files with just different case, so the
|
|
configuration fails.
|
|
</para>
|
|
<para>To help with this problem, Cygwin supports casesensitivity
|
|
starting with Cygwin 1.7.0. For a detailed description how to use that
|
|
feature see the Cygwin User's Guilde at
|
|
<ulink url="http://cygwin.com/cygwin-ug-net/using-specialnames.html">http://cygwin.com/cygwin-ug-net/using-specialnames.html</ulink>.
|
|
</para>
|
|
|
|
</answer></qandaentry>
|
|
|
|
<qandaentry id="faq.using.dos-filenames">
|
|
<question><para>What about DOS special filenames?</para></question>
|
|
<answer>
|
|
|
|
<para>In Windows, files cannot be named com1, lpt1, or aux (to name a few);
|
|
either as the root filename or as the extension part. If you do, you'll have
|
|
trouble. Unix programs don't avoid these names which can make things
|
|
interesting. E.g., the perl distribution has a file called
|
|
<literal>aux.sh</literal>. The perl configuration tries to make sure that
|
|
<literal>aux.sh</literal> is there, but an operation on a file with the magic
|
|
letters 'aux' in it will hang.
|
|
</para>
|
|
<para>At least that's what happens when using native Windows tools. Cygwin
|
|
1.7.0 and later can deal with these filenames just fine. Again, see the
|
|
User's Guide at
|
|
<ulink url="http://cygwin.com/cygwin-ug-net/using-specialnames.html">http://cygwin.com/cygwin-ug-net/using-specialnames.html</ulink>
|
|
for a detailed description of what's possible with filenames and what is not.
|
|
</para>
|
|
</answer></qandaentry>
|
|
|
|
<qandaentry id="faq.using.hangs">
|
|
<question><para>When it hangs, how do I get it back?</para></question>
|
|
<answer>
|
|
|
|
<para>If something goes wrong and the tools hang on you for some reason (easy
|
|
to do if you try and read a file called aux.sh), first try hitting ^C to
|
|
return to bash or the cmd prompt.
|
|
</para>
|
|
<para>If you start up another shell, and applications don't run, it's a good
|
|
bet that the hung process is still running somewhere. Use the Task
|
|
Manager, pview, or a similar utility to kill the process.
|
|
</para>
|
|
<para>And, if all else fails, there's always the reset button/power switch.
|
|
In theory this should never be necessary, though.
|
|
</para>
|
|
</answer></qandaentry>
|
|
|
|
<qandaentry id="faq.using.directory-structure">
|
|
<question><para>Why the weird directory structure?</para></question>
|
|
<answer>
|
|
|
|
<para>Why do /lib and /usr/lib (and /bin, /usr/bin) point to the same thing?
|
|
</para>
|
|
<para>Why use mounts instead of symbolic links?
|
|
</para>
|
|
<para>Can I use a disk root (e.g., C:\) as Cygwin root? Why is this discouraged?
|
|
</para>
|
|
<para>After a new installation in the default location, your mount points will
|
|
look something like this:
|
|
</para>
|
|
<screen>
|
|
bash$ mount
|
|
C:\cygwin\bin on /usr/bin type system (binmode)
|
|
C:\cygwin\lib on /usr/lib type system (binmode)
|
|
C:\cygwin on / type system (binmode)
|
|
</screen>
|
|
|
|
<para>(Exactly what you see depends on what options you gave to <literal>setup.exe</literal>.)
|
|
</para>
|
|
<para>Note that /bin and /usr/bin point to the same location, as do /lib and
|
|
/usr/lib. This is intentional, and you should not undo these mounts
|
|
unless you <emphasis>really</emphasis> know what you are doing.
|
|
</para>
|
|
<para>Various applications and packages may expect to be installed in /lib or
|
|
/usr/lib (similarly /bin or /usr/bin). Rather than distinguish between
|
|
them and try to keep track of them (possibly requiring the occasional
|
|
duplication or symbolic link), it was decided to maintain only one
|
|
actual directory, with equivalent ways to access it.
|
|
</para>
|
|
<para>Symbolic links had been considered for this purpose, but were dismissed
|
|
because they do not always work on Samba drives. Also, mounts are
|
|
faster to process because no disk access is required to resolve them.
|
|
</para>
|
|
<para>Note that non-cygwin applications will not observe Cygwin mounts (or
|
|
symlinks for that matter). For example, if you use WinZip to unpack the
|
|
tar distribution of a Cygwin package, it may not get installed to the
|
|
correct Cygwin path. <emphasis>So don't do this!</emphasis>
|
|
</para>
|
|
<para>It is strongly recommended not to make the Cygwin root directory the
|
|
same as your drive's root directory, unless you know what you are doing
|
|
and are prepared to deal with the consequences. It is generally easier
|
|
to maintain the Cygwin hierarchy if it is isolated from, say, C:\. For
|
|
one thing, you avoid possible collisions with other (non-cygwin)
|
|
applications that may create (for example) \bin and \lib directories.
|
|
(Maybe you have nothing like that installed now, but who knows about
|
|
things you might add in the future?)
|
|
</para>
|
|
</answer></qandaentry>
|
|
|
|
<qandaentry id="faq.using.anti-virus">
|
|
<question><para>How do anti-virus programs like Cygwin?</para></question>
|
|
<answer>
|
|
|
|
<para>Users have reported that NAI (formerly McAfee) VirusScan for NT (and
|
|
others?) is incompatible with Cygwin. This is because it tries to scan
|
|
the newly loaded shared memory in cygwin1.dll, which can cause fork() to
|
|
fail, wreaking havoc on many of the tools. (It is not confirmed that
|
|
this is still a problem, however.)
|
|
</para>
|
|
<para>There have been several reports of NAI VirusScan causing the system to
|
|
hang when unpacking tar.gz archives. This is surely a bug in VirusScan,
|
|
and should be reported to NAI. The only workaround is to disable
|
|
VirusScan when accessing these files. This can be an issue during
|
|
setup, and is discussed in that FAQ entry.
|
|
</para>
|
|
<para>Some users report a significant performance hit using Cygwin when their
|
|
anti-virus software is enabled. Rather than disable the anti-virus
|
|
software completely, it may be possible to specify directories whose
|
|
contents are exempt from scanning. In a default installation, this
|
|
would be <literal>C:\cygwin\bin</literal>. Obviously, this could be
|
|
exploited by a hostile non-Cygwin program, so do this at your own risk.
|
|
</para>
|
|
<para>See also <ulink url="http://cygwin.com/faq/faq.using.html#faq.using.bloda" />
|
|
for a list of applications that have been known, at one time or another, to
|
|
interfere with the normal functioning of Cygwin.
|
|
</para>
|
|
</answer></qandaentry>
|
|
|
|
<qandaentry id="faq.using.emacs">
|
|
<question><para>Is there a Cygwin port of GNU Emacs?</para></question>
|
|
<answer>
|
|
|
|
<para>Yes. It uses the X11 (<ulink url="http://cygwin.com/xfree/">http://cygwin.com/xfree/</ulink>) GUI. Right now the package is old and outdated.
|
|
Consider using XEmacs for now.
|
|
</para>
|
|
</answer></qandaentry>
|
|
|
|
<qandaentry id="faq.using.xemacs">
|
|
<question><para>Is there a Cygwin port of XEmacs?</para></question>
|
|
<answer>
|
|
|
|
<para>Yes. It can be used in three different modes:</para>
|
|
<para><itemizedlist>
|
|
<listitem><para>X11 (<ulink url="http://cygwin.com/xfree/">http://cygwin.com/xfree/</ulink>) GUI</para></listitem>
|
|
</itemizedlist></para>
|
|
<para>You have to <emphasis>set</emphasis> the DISPLAY environment variable
|
|
before starting xemacs.</para>
|
|
<screen>
|
|
bash$ DISPLAY=127.0.0.1:0 xemacs &
|
|
</screen>
|
|
<para><itemizedlist>
|
|
<listitem><para>Windows native GUI</para></listitem>
|
|
</itemizedlist></para>
|
|
<para>You have to <emphasis>unset</emphasis> the DISPLAY environment variable
|
|
before starting xemacs.</para>
|
|
<screen>
|
|
bash$ DISPLAY= xemacs &
|
|
</screen>
|
|
<para><itemizedlist>
|
|
<listitem><para>Console mode</para></listitem>
|
|
</itemizedlist></para>
|
|
<para>Start xemacs with -nw in a terminal (native or X11) window</para>
|
|
<screen>
|
|
bash$ xemacs -nw
|
|
</screen>
|
|
<para>The current stable Cygwin version of XEmacs is 21.4.x. But there is also a
|
|
Cygwin test release version (21.5.x) available for download via setup.exe.
|
|
</para>
|
|
<para>To use all the standard packages with XEmacs you should download the following
|
|
two packages:</para>
|
|
<para><itemizedlist>
|
|
<listitem><para>xemacs-sumo - XEmacs standard packages</para></listitem>
|
|
<listitem><para>xemacs-mule-sumo - XEmacs MULE (MUlti Lingual Emacs) packages</para></listitem>
|
|
</itemizedlist></para>
|
|
<para>An alternative <emphasis>native</emphasis> distribution of XEmacs for
|
|
Windows based systems can be downloaded from
|
|
<ulink url="http://xemacs.org/Download/win32/index.html">http://xemacs.org/Download/win32/index.html</ulink>.
|
|
It uses an <emphasis>InnoSetup Kit</emphasis> based installer.</para>
|
|
</answer></qandaentry>
|
|
|
|
<qandaentry id="faq.using.ntemacs">
|
|
<question><para>What about NT Emacs?</para></question>
|
|
<answer>
|
|
|
|
<para>If you want GNU Emacs with a native Microsoft GUI interface,
|
|
then you can either use XEmacs (see above), or native
|
|
NT Emacs: see section
|
|
<ulink url="http://www.gnu.org/software/emacs/windows/Getting-Emacs.html#Getting-Emacs">Where can I get pre-compiled versions?</ulink> in NT Emacs FAQ.
|
|
|
|
</para>
|
|
<para>NT Emacs uses the Windows command shell by default. Since it is not a
|
|
Cygwin application, it has no knowledge of Cygwin mounts. With those
|
|
points in mind, you need to add the following code to your ~/.emacs
|
|
(or ~/_emacs) file in order to use Cygwin bash. This is particularly useful
|
|
for the JDEE package (<ulink url="http://jdee.sunsite.dk/">http://jdee.sunsite.dk/</ulink>). The following
|
|
settings are for Emacs 21.1:
|
|
</para>
|
|
<screen>
|
|
|
|
;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
|
;; Initial setup
|
|
;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
|
|
|
;; This assumes that Cygwin is installed in C:\cygwin (the
|
|
;; default) and that C:\cygwin\bin is not already in your
|
|
;; Windows Path (it generally should not be).
|
|
|
|
(setq exec-path (cons "C:/cygwin/bin" exec-path))
|
|
(setenv "PATH" (concat "C:\\cygwin\\bin;" (getenv "PATH")))
|
|
|
|
;; LOGNAME and USER are expected in many Emacs packages
|
|
;; Check these environment variables.
|
|
|
|
(if (and (null (getenv "USER"))
|
|
;; Windows includes variable USERNAME, which is copied to
|
|
;; LOGNAME and USER respectively.
|
|
(getenv "USERNAME"))
|
|
(setenv "USER" (getenv "USERNAME")))
|
|
|
|
(if (and (getenv "LOGNAME")
|
|
;; Bash shell defines only LOGNAME
|
|
(null (getenv "USER")))
|
|
(setenv "USER" (getenv "LOGNAME")))
|
|
|
|
(if (and (getenv "USER")
|
|
(null (getenv "LOGNAME")))
|
|
(setenv "LOGNAME" (getenv "USER")))
|
|
|
|
;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
|
;; (A) M-x shell: This change M-x shell permanently
|
|
;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
|
|
|
;; Would call Windows command interpreter. Change it.
|
|
|
|
(setq shell-file-name "bash")
|
|
(setenv "SHELL" shell-file-name)
|
|
(setq explicit-shell-file-name shell-file-name)
|
|
|
|
;; Remove C-m (^M) characters that appear in output
|
|
|
|
(add-hook 'comint-output-filter-functions
|
|
'comint-strip-ctrl-m)
|
|
|
|
;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
|
;; (B) *OR* call following function with M-x my-bash
|
|
;; The M-x shell would continue to run standard Windows shell
|
|
;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
|
|
|
(defun my-bash (&optional buffer)
|
|
"Run Cygwin Bash shell in optional BUFFER; default *shell-bash*."
|
|
(autoload 'comint-check-proc "comint")
|
|
(interactive
|
|
(let ((name "*shell-bash*"))
|
|
(if current-prefix-arg
|
|
(setq name (read-string
|
|
(format "Cygwin shell buffer (default %s): " name)
|
|
(not 'initial-input)
|
|
(not 'history)
|
|
name)))
|
|
(list name)))
|
|
(or buffer
|
|
(setq buffer "*shell-bash*"))
|
|
(if (comint-check-proc buffer)
|
|
(pop-to-buffer buffer)
|
|
(let* ((shell-file-name "bash")
|
|
(explicit-shell-file-name shell-file-name)
|
|
(explicit-sh-args '("--login" "-i"))
|
|
(explicit-bash-args explicit-sh-args)
|
|
(w32-quote-process-args ?\"));; Use Cygwin quoting rules.
|
|
(shell buffer)
|
|
;; By default Emacs sends "\r\n", but bash wants plain "\n"
|
|
(set-buffer-process-coding-system 'undecided-dos 'undecided-unix)
|
|
;; With TAB completion, add slash path separator, none to filenames
|
|
(make-local-variable 'comint-completion-addsuffix)
|
|
(setq comint-completion-addsuffix '("/" . ""))
|
|
;; This variable is local to buffer
|
|
(setq comint-prompt-regexp "^[ \n\t]*[$] ?"))))
|
|
|
|
</screen>
|
|
|
|
<para>If you want NT Emacs to understand Cygwin paths, get
|
|
cygwin-mount.el from <ulink url="http://www.emacswiki.org/elisp/index.html">http://www.emacswiki.org/elisp/index.html</ulink>.
|
|
</para>
|
|
<para>Note that all of this ``just works'' if you use the Cygwin port of
|
|
Emacs or XEmacs from Cygwin Setup.
|
|
</para>
|
|
</answer></qandaentry>
|
|
|
|
<qandaentry id="faq.using.console-window">
|
|
<question><para>Is there a better alternative to the standard console window?</para></question>
|
|
<answer>
|
|
|
|
<para>Yes! Use rxvt or mintty instead. Both are optional packages in
|
|
Cygwin Setup. You can use rxvt with or without X11, while mintty is a
|
|
Cygwin application providing a native GUI.
|
|
</para>
|
|
</answer></qandaentry>
|
|
|
|
<qandaentry id="faq.using.symlinks-samba">
|
|
<question><para>Why don't symlinks work on samba-mounted filesystems?</para></question>
|
|
<answer>
|
|
|
|
<para>Symlinks are marked with "system" file attribute. Samba does not
|
|
enable this attribute by default. To enable it, consult your Samba
|
|
documentation and then add these lines to your samba configuration
|
|
file:
|
|
</para>
|
|
<screen>
|
|
map system = yes
|
|
create mask = 0775
|
|
</screen>
|
|
|
|
<para>Note that the 0775 can be anything as long as the 0010 bit is set.
|
|
</para>
|
|
<para>Alternatively, use Windows shortcuts as symlinks. See the CYGWIN
|
|
environment variable option "winsymlinks"
|
|
<ulink url="http://cygwin.com/cygwin-ug-net/using-cygwinenv.html">http://cygwin.com/cygwin-ug-net/using-cygwinenv.html</ulink>
|
|
</para>
|
|
</answer></qandaentry>
|
|
|
|
<qandaentry id="faq.using.tcl-tk">
|
|
<question><para>Why doesn't Cygwin tcl/tk understand Cygwin paths?</para></question>
|
|
<answer>
|
|
|
|
<para>The versions of Tcl/Tk distributed with Cygwin (e.g. cygtclsh80.exe,
|
|
cygwish80.exe) are not actually "Cygwin versions" of those tools.
|
|
They are built as native libraries, which means they do not understand
|
|
Cygwin mounts or symbolic links.
|
|
</para>
|
|
<para>See the entry "How do I convert between Windows and UNIX paths?"
|
|
elsewhere in this FAQ.
|
|
</para></answer></qandaentry>
|
|
|
|
<qandaentry id="faq.using.bloda">
|
|
<question><para>What applications have been found to interfere with Cygwin?</para></question>
|
|
<answer>
|
|
|
|
<para>From time to time, people have reported strange failures and problems in
|
|
Cygwin and Cygwin packages that seem to have no rational explanation. Among
|
|
the most common symptoms they report are fork failures, memory leaks, and file
|
|
access denied problems. These problems, when they have been traced, often appear
|
|
to be caused by interference from other software installed on the same PC. Security
|
|
software, in particular, such as anti-virus, anti-spyware, and firewall applications,
|
|
often implements its functions by installing hooks into various parts of the system,
|
|
including both the Explorer shell and the underlying kernel. Sometimes these hooks
|
|
are not implemented in an entirely transparent fashion, and cause changes in the
|
|
behaviour which affect the operation of other programs, such as Cygwin.
|
|
</para>
|
|
<para>Among the software that has been found to cause difficulties are:</para>
|
|
<para><itemizedlist>
|
|
<listitem><para>Sonic Solutions burning software containing DLA component</para></listitem>
|
|
<listitem><para>Norton/MacAffee/Symantec antivirus or antispyware</para></listitem>
|
|
<listitem><para>Logitech webcam software with "Logitech process monitor" service</para></listitem>
|
|
<listitem><para>Kerio, Agnitum or ZoneAlarm Personal Firewall</para></listitem>
|
|
<listitem><para>Iolo System Mechanic/AntiVirus/Firewall</para></listitem>
|
|
<listitem><para>LanDesk</para></listitem>
|
|
<listitem><para>Windows Defender </para></listitem>
|
|
<listitem><para>Embassy Trust Suite fingerprint reader software wxvault.dll</para></listitem>
|
|
<listitem><para>NOD32 Antivirus</para></listitem>
|
|
<listitem><para>ByteMobile laptop optimization client</para></listitem>
|
|
</itemizedlist></para>
|
|
<para>Sometimes these problems can be worked around, by temporarily or partially
|
|
disabling the offending software. For instance, it may be possible to disable
|
|
on-access scanning in your antivirus, or configure it to ignore files under the
|
|
Cygwin installation root. Often, unfortunately, this is not possible; even disabling
|
|
the software may not work, since many applications that hook the operating system
|
|
leave their hooks installed when disabled, and simply set them into what is intended
|
|
to be a completely transparent pass-through mode. Sometimes this pass-through is not
|
|
as transparent as all that, and the hooks still interfere with Cygwin; in these cases,
|
|
it may be necessary to uninstall the software altogether to restore normal operation.
|
|
</para>
|
|
<para>Some of the symptoms you may experience are:</para>
|
|
<para><itemizedlist>
|
|
<listitem>
|
|
<para>Random fork() failures.</para>
|
|
<para>Caused by hook DLLs that load themselves into every process in the
|
|
system. POSIX fork() semantics require that the memory map of the child process
|
|
must be an exact duplicate of the parent process' layout. If one of these DLLs
|
|
loads itself at a different base address in the child's memory space as compared
|
|
to the address it was loaded at in the parent, it can end up taking the space that
|
|
belonged to a different DLL in the parent. When Cygwin can't load the original
|
|
DLL at that same address in the child, the fork() call has to fail.
|
|
</para>
|
|
</listitem>
|
|
<listitem>
|
|
<para>File access problems.</para>
|
|
<para>Some programs (e.g., virus scanners with on-access scanning) scan or
|
|
otherwise operate on every file accessed by all the other software running on
|
|
your computer. In some cases they may retain an open handle on the file even
|
|
after the software that is really using the file has closed it. This has been
|
|
known to cause operations such as deletes, renames and moves to fail with
|
|
access denied errors. In extreme cases it has been known for scanners to leak
|
|
file handles, leading to kernel memory starvation.
|
|
</para>
|
|
</listitem>
|
|
<listitem>
|
|
<para>Networking issues</para>
|
|
<para>Firewall software sometimes gets a bit funny about Cygwin. It's not
|
|
currently understood why; Cygwin only uses the standard Winsock2 API, but
|
|
perhaps in some less-commonly used fashion that doesn't get as well tested
|
|
by the publishers of firewalls. Symptoms include mysterious failures to
|
|
connect, or corruption of network data being sent or received.</para>
|
|
</listitem>
|
|
<listitem>
|
|
<para>Memory and/or handle leaks</para>
|
|
<para>Some applications that hook into the Windows operating system exhibit
|
|
bugs when interacting with Cygwin that cause them to leak allocated memory
|
|
or other system resources. Symptoms include complaints about out-of-memory
|
|
errors and even virtual memory exhaustion dialog boxes from the O/S; it is
|
|
often possible to see the excess memory allocation using a tool such as
|
|
Task Manager or Sysinternals' Process Explorer, although interpreting the
|
|
statistics they present is not always straightforward owing to complications
|
|
such as virtual memory paging and file caching.</para>
|
|
</listitem>
|
|
</itemizedlist></para>
|
|
</answer></qandaentry>
|