how-using.texinfo

cygwin, 著名的在win32下模拟unix操作系统的东东

@section Using Cygwin

@subsection Why can't my application locate cygncurses5.dll?  or cygintl.dll?  or cygreadline5.dll?  or ...?

If you upgraded recently, and suddenly vim (or some other Cygwin
application) cannot find @code{cygncurses5.dll}, it means that you did
not follow these instructions properly:
@file{http://cygwin.com/ml/cygwin-announce/2001/msg00124.html}.  To
repair the damage, you must run Cygwin Setup again, and re-install the
@samp{libncurses5} package.

Note that Cygwin Setup won't show this option by default.  In the
``Select packages to install'' dialogue, click on the @samp{Full/Part}
button.  This lists all packages, even those that are already
installed.  Scroll down to locate the @samp{libncurses5} package.
Click on the ``cycle'' glyph until it says ``Reinstall''.  Continue
with the installation.

Similarly, if something cannot find @code{cygintl.dll}, then run
Cygwin Setup and re-install the @samp{libintl} and @samp{libintl1}
packages.

For a detailed explanation of the general problem, and how to extend
it to other missing DLLs (like cygreadline5.dll) and identify their
containing packages, see
@file{http://cygwin.com/ml/cygwin/2002-01/msg01619.html}.

@subsection Why is Cygwin suddenly @emph{so} slow?

If you recently upgraded the @samp{cygwin} package and suddenly
@emph{every} command takes a @emph{very} long time, then you probably
have the obsolete @code{//c} notation in your PATH.  This now means
the @emph{network share} @code{c}, which will slow things down
tremendously if it does not exist.  See then next FAQ entry.

@subsection Why doesn't //c (for C:) work anymore?

(Similarly for any drive letter, e.g. @code{//z} for @code{Z:})

This ``feature'' has long been deprecated, and no longer works at all
in the latest release.  As of release 1.3.3, @code{//c} now means the
@emph{network share} @code{c}.

For a detailed discussion of why this change was made, and how deal
with it now, refer to
@file{http://sources.redhat.com/ml/cygwin/2001-09/msg00014.html}.

@subsection How should I set my PATH?

This is done for you in the file /etc/profile, which is sourced by bash
when you start it from the Desktop or Start Menu shortcut, created by
@code{setup.exe}.  The line is

@example
	PATH="/usr/local/bin:/usr/bin:/bin:$PATH"
@end example

Effectively, this @strong{prepends} /usr/local/bin and /usr/bin to your
Windows system path.  If you choose to reset your PATH, say in
$HOME/.bashrc, or by editing etc/profile directly, then you should
follow this rule.  You @strong{must} have @code{/usr/bin} in your PATH
@strong{before} any Windows system directories.  (And you must not omit
the Windows system directories!)  Otherwise you will likely encounter
all sorts of problems running Cygwin applications.

@subsection Bash says "command not found", but it's right there!

If you compile a program, you might find that you can't run it:

@example
	bash$ gcc -o hello hello.c
        bash$ hello
        bash: hello: command not found
@end example

Unlike Windows, bash does not look for programs in @samp{.} (the current
directory) by default.  You can add @samp{.} to your PATH (see above),
but this is not recommended (at least on UNIX) for security reasons.
Just tell bash where to find it, when you type it on the command line:

@example
	bash$ gcc -o hello hello.c
        bash$ ./hello
        Hello World!
@end example

@subsection How do I convert between Windows and UNIX paths?

Use the 'cygpath' utility.  Type '@code{cygpath --help}' for
information.  For example (on my installation):
@example
	bash$ cygpath --windows ~/.bashrc
        D:\starksb\.bashrc
        bash$ cygpath --unix C:/cygwin/bin/cygwin.bat
        /usr/bin/cygwin.bat
        bash$ cygpath --unix C:\\cygwin\\bin\\cygwin.bat
        /usr/bin/cygwin.bat
@end example
Note that bash interprets the backslash '\' as an escape character, so
you must type it twice in the bash shell if you want it to be recognized
as such.

@subsection Why doesn't bash read my .bashrc file on startup?

Your .bashrc is read from your home directory specified by the HOME
environment variable.  It uses /.bashrc if HOME is not set.  So you need
to set HOME correctly, or move your .bashrc to the top of the drive
mounted as / in Cygwin.

@subsection How can I get bash filename completion to be case insensitive?

Add the following to your @code{~/.bashrc} file:

@example
	shopt -s nocaseglob
@end example

and add the following to your @code{~/.inputrc} file:

@example
	set completion-ignore-case on
@end example

@subsection Can I use paths/filenames containing spaces in them?

Cygwin does support spaces in filenames and paths.  That said, some
utilities that use the library may not, since files don't typically
contain spaces in Unix.  If you stumble into problems with this, you
will need to either fix the utilities or stop using spaces in filenames
used by Cygwin tools.

In particular, bash interprets space as a word separator.  You would have
to quote a filename containing spaces, or escape the space character.
For example:
@example
	bash-2.03$ cd '/cygdrive/c/Program Files'
@end example
or
@example
	bash-2.03$ cd /cygdrive/c/Program\ Files
@end example

@subsection Why can't I cd into a shortcut to a directory?

This is only valid up to but not including version 1.3.0:

Cygwin does not follow MS Windows Explorer Shortcuts (*.lnk files).  It
sees a shortcut as a regular file and this you cannot "cd" into it.

Some people have suggested replacing the current symbolic link scheme
with shortcuts.  The major problem with this is that .LNK files would
then be used to symlink Cygwin paths that may or may not be valid
under native Win32 non-Cygwin applications such as Explorer.

Since version 1.3.0, Cygwin treats shortcuts as symlinks.

@subsection I'm having basic problems with find.  Why?

Make sure you are using the find that came with Cygwin and that you
aren't picking up the Win32 find command instead.  You can verify that
you are getting the right one by doing a "type find" in bash.

If the path argument to find, including current directory (default), is
itself a symbolic link, then find will not traverse it unless you
specify the @samp{-follow} option.  This behavior is different than most
other UNIX implementations, but is not likely to change.

@subsection Where is the @samp{su} command?

The @samp{su} command is not ported to Cygwin, so it is no longer
provided in the distribution.  You may be able to use @samp{login}
instead, but you should read
@file{http://www.cygwin.com/ml/cygwin/2001-03/msg00337.html} first.

If you have a copy of su, then it's from an old Cygwin distribution, and
it probably doesn't work properly anyway.

@subsection Why doesn't man (or apropos) work?

Even after installing the @samp{man} package, you get an error like this:

@example
	bash-2.04$ man man
	Error executing formatting or display command.
	System command (cd /usr/man ; (echo -e ".pl 1100i"; cat /usr/man/man1/man.1; echo ".pl \n(nlu+10") | /usr/bin/tbl | /usr/bin/groff -Tascii -mandoc | less -is) exited with status 32512.
	No manual entry for man
@end example

You also need /bin/sh, which is found in the @samp{ash} package.
You must install this too.

In addition, before you can use @samp{man -k} or @samp{apropos}, you
must create the whatis database.  Just run the command

@example
	/usr/sbin/makewhatis
@end example

(it may take a minute to complete).

@subsection Why doesn't chmod work?

@samp{ntsec} will allow UNIX permissions in Windows NT on NTFS file
systems.  This is on by default (a recent change).

@samp{ntea} works on NTFS @emph{and} FAT but it creates a huge,
@strong{undeletable} file on FAT filesystems.

(The @samp{ntsec} and @samp{ntea} settings are values for the
@samp{CYGWIN} environment variable.  See the Cygwin User's Guide at
@file{http://cygwin.com/cygwin-ug-net/cygwin-ug-net.html} for more
information on this variable and its settings.)

There is no solution at all for Windows 9x.

If you have an application that requires a certain permission mode on a
file, you may be able to work around this requirement by modifying the
application's source code.  For a hint, based on work done by Corinna
Vinschen for OpenSSH, see this message from the cygwin mailing list:
@file{http://cygwin.com/ml/cygwin/2000-11/msg01176.html}.

@subsection Why doesn't @samp{mkdir -p} work on a network share?

Unfortunately, you cannot do something like this:

@example
bash$ mkdir -p //MACHINE/Share/path/to/new/dir
mkdir: cannot create directory `//MACHINE': No such file or directory
@end example

This is because mkdir checks for the existence of each directory on the
path, creating them as necessary.  Since @samp{//MACHINE} is not a
directory (you can't cd to it either), mkdir tries to create it, and
fails.

This might get fixed someday, but for now, you have to work around it:

@example
bash$ cd //MACHINE/Share
bash$ mkdir -p path/to/new/dir
@end example

@subsection Why doesn't my shell script work?

There are two basic problems you might run into.  One is the fact that
/bin/sh is really ash, and is missing some features you might expect
in /bin/sh, particularly if you are used to /bin/sh actually being
bash (Linux) or ksh (Tru64).  For example:

@itemize bullet
@item No job control
@item No getopts
@item No let
@item No functions exported
@item Must use `.' instead of `source' (true of sh and ksh too, not just ash)
@end itemize

Or, it could be a permission problem, and Cygwin doesn't understand that
your script is executable.  Because @samp{chmod} may not work (see FAQ
entry above), Cygwin must read the contents of files to determine if
they are executable.  If your script does not start with

@example
	#! /bin/sh
@end example

(or any path to a script interpreter, it does not have to be /bin/sh)
then Cygwin will not know it is an executable script.  The Bourne shell
idiom

@example
	:
	# This is the 2nd line, assume processing by /bin/sh
@end example

also works.

Note that you can use @samp{mount -x} to force Cygwin to treat all files
under the mount point as executable.  This can be used for individual
files as well as directories.  Then Cygwin will not bother to read files
to determine whether they are executable.

@subsection How do I print under Cygwin?

There is no working lp or lpr system as you would find on UNIX.

Jason Tishler has written a couple of messages that explain how to use
a2ps (for nicely formatted text in PostScript) and ghostscript (to print
PostScript files on non-PostScript Windows printers).  Start at
@file{http://cygwin.com/ml/cygwin/2001-04/msg00657.html}.  Note that the
@samp{file} command is now available as part of Cygwin setup.

Alternatively, on NT, you can use the Windows @samp{print} command.  (It
does not seem to be available on Win9x.)  Type

@example
	bash$ print /\?
@end example

for usage instructions (note the @samp{?} must be escaped from the
shell).

Finally, you can simply @samp{cat} the file to the printer's share name:

@example
	bash$ cat myfile > //host/printer
@end example

You may need to press the formfeed button on your printer or append the
formfeed character to your file.

@subsection Why don't international (8-bit) characters work?

Before you can type international characters (ｅ漩) in bash, you must
add the following lines to your @code{~/.inputrc} file:

@example
	set meta-flag on 
        set convert-meta off 
        set output-meta on 
@end example

These are options to the @code{readline} library, which you can read
about in the @code{bash(1)} man page.

@subsection Why don't cursor keys work under Win95/Win98?

@strong{(Please note: This section has not yet been updated for the latest
net release.)}

Careful examination shows that they not just non-functional, but
rather behave strangely, for example, with NumLock off, keys on numeric
keyboard work, until you press usual cursor keys, when even numeric
stop working, but they start working again after hitting alphanumeric
key, etc. This reported to happen on localized versions of Win98 and
Win95, and not specific to Cygwin (there're known cases of Alt+Enter
(fullscreen/windowed toggle) not working and shifts sticking with
other programs). The cause of this problem is Microsoft keyboard
localizer which by default installed in 'autoexec.bat'. Corresponding
line looks like:

@example
keyb ru,,C:\WINDOWS\COMMAND\keybrd3.sys
@end example

(That's for russian locale.) You should comment that line if you want
your keys working properly. Of course, this will deprive you of your
local alphabet keyboard support, so you should think about
another localizer. exUSSR users are of course knowledgeable of Keyrus
localizer, and it might work for other locales too, since it has keyboard
layout editor. But it has russian messages and documentation ;-(
Reference URL is http://www.hnet.ru/software/contrib/Utils/KeyRus/
(note the you may need to turn off Windows logo for Keyrus to operate
properly).

@subsection Is it OK to have multiple copies of the DLL?

You should only have one copy of the Cygwin DLL on your system.  If you
have multiple versions, they will conflict and cause problems.

If you get the error "shared region is corrupted" or "shared region
version mismatch" it means you have multiple versions of cygwin1.dll
running at the same time.  This could happen, for example, if you update
cygwin1.dll without exiting @emph{all} Cygwin apps (including inetd)
beforehand.

If you're trying to find multiple versions of the DLL that are causing
this problem, reboot first, in case DLL's still loaded in memory are the