how-using.texinfo

cygwin, 著名的在win32下模拟unix操作系统的东东

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).

@subsection Where can I find "more"?

If you are looking for the "more" pager, you should use the "less" pager
instead.

@subsection Why isn't package XXXX available in Cygwin?  (Or, why is your package so out of date?)

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 below.

@subsection How can I access other drives?

You have some flexibility here.

Cygwin has a builtin "cygdrive prefix" for drives that are not mounted.
You can access any drive, say Z:, as '/cygdrive/z/'.

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:
@example
	bash$ cd C:/Windows
	bash$ pwd
        /cygdrive/c/Windows
@end example
and
@example
	bash$ cd C:/cygwin
	bash$ pwd
        /
@end example
for a default setup.  You could also use backward-slashes in the
Windows path, but these would have to be escaped from the shell.

@strong{Warning:} 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.

You can avoid the ambiguity of Windows paths, and avoid typing
"/cygdrive", by explicitly mounting drives to posix paths.  For example:
@example
	bash$ mkdir /c
	bash$ mount c:/ /c
	bash$ ls /c
@end example
Then @samp{/cygdrive/c/Windows} becomes @samp{/c/Windows} which is a
little less typing.

Note that you only need to mount drives once.  The mapping is kept
in the registry so mounts stay valid pretty much indefinitely.
You can only get rid of them with umount, or the registry editor.

The '-b' option to mount mounts the mountpoint in binary mode
("binmode") where text and binary files are treated equivalently.  This
should only be necessary for badly ported Unix programs where binary
flags are missing from open calls.  It is also the setting for /,
/usr/bin and /usr/lib in a default Cygwin installation.  The default for
new mounts is text mode ("textmode"), which is also the mode for all
"cygdrive" mounts.

You can change the default @samp{cygdrive} prefix and whether it is
binmode or textmode using the @code{mount} command.  For example,
@example
	bash$ mount -b --change-cygdrive-prefix cygdrive
@end example
will change all @code{/cygdrive/...} mounts to binmode.

@subsection How can I copy and paste into Cygwin console windows?

First, consider using rxvt instead of the standard console window.  In
rxvt, selecting with the left-mouse also copies, and middle-mouse
pastes.  It couldn't be easier!

Under Windows NT, open the properties dialog of the console window.
The options contain a toggle button, named "Quick edit mode".  It must
be ON.  Save the properties.

Under Windows 9x, open the properties dialog of the console window.
Select the Misc tab.  Uncheck Fast Pasting.  Check QuickEdit.

You can also bind the insert key to paste from the clipboard by adding 
the following line to your .inputrc file: 
@example
	"\e[2~": paste-from-clipboard 
@end example 


@subsection What does "mount failed: Device or resource busy" mean?

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

This usually means that you are trying to mount to a location
already in use by mount.  For example, if c: is mounted as '/'
and you try to mount d: there as well, you will get this error
message.  First "umount" the old location, then "mount" the new one and
you should have better luck.

If you are trying to umount '/' and are getting this message, you may
need to run @code{regedit.exe} and change the "native" key for the '/'
mount in one of the mount points kept under
HKEY_CURRENT_USER/Software/Red Hat, Inc./CYGWIN.DLL setup/<version>
where <version> is the latest registry version associated with the
Cygwin library.

@subsection How can I share files between Unix and Windows?

During development, we have both Unix boxes running Samba and
NT/Windows 95/98 machines.  We often build with cross-compilers
under Unix and copy binaries and source to the Windows system
or just toy with them directly off the Samba-mounted partition.
On dual-boot NT/Windows 9x machines, we usually use the FAT
filesystem so we can also access the files under Windows 9x.

@subsection Are mixed-case filenames possible with Cygwin?

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 @code{Makefile} and
@code{makefile}.  WIN32 can't tell the difference between files with
just different case, so the configuration fails.

In releases prior to beta 16, mount had a special mixed case option
which renamed files in such a way as to allow mixed case filenames.  We
chose to remove the support when we rewrote the path handling code for
beta 16.  The standard Windows apps -- explorer.exe,
cmd.exe/command.com, etc. -- do not distinguish filenames that differed
only in case, resulting in some (very) undesirable behavior.

Sergey Okhapkin had maintained a mixed-case patch ('coolview') until
about B20.1, but this has not been updated to recent versions of Cygwin.

@subsection What about DOS special filenames?

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
@code{aux.sh}.  The perl configuration tries to make sure that
@code{aux.sh} is there, but an operation on a file with the magic
letters 'aux' in it will hang.

@subsection When it hangs, how do I get it back?

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.

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.

And, if all else fails, there's always the reset button/power switch.
This should never be necessary under Windows NT.

@subsection Why the weird directory structure?

Why do /lib and /usr/lib (and /bin, /usr/bin) point to the same thing?

Why use mounts instead of symbolic links?

Can I use a disk root (e.g., C:\) as Cygwin root?  Why is this discouraged?

After a new installation in the default location, your mount points will
look something like this:

@example
	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)
@end example

(Exactly what you see depends on what options you gave to @code{setup.exe}.)

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 @emph{really} know what you are doing.

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.

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.

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.  @emph{So don't do this!}

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?)

@subsection How do anti-virus programs like Cygwin?

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.)

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.

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 @samp{@code{C:\cygwin\bin}}.  Obviously, this could be
exploited by a hostile non-Cygwin program, so do this at your own risk.

@subsection Is there a Cygwin port of GNU Emacs?

Yes!  It uses the X11 (@file{http://cygwin.com/xfree/}) Windows
interface.  From a remote login shell, this ``emacs -nw'' works fine.
There is also a non-X11 version which just provides the text-only
terminal interface.  Use Cygwin Setup to install either one (or both).

@subsection What about NT Emacs?

If you want GNU Emacs with a native Microsoft Windows interface, but
without X, then you must use the native Windows port, commonly known
as ``NT Emacs''.  You get NT Emacs from any GNU mirror.  It is not
available from Cygwin Setup.

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 (@file{http://jdee.sunsite.dk/}).  The following
settings are for Emacs 21.1:

@example
	;; 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")))
	;;
	;; NT-emacs assumes a Windows command shell, which you change
	;; here.
	;;
	(setq process-coding-system-alist '(("bash" . undecided-unix)))
	(setq shell-file-name "bash")
	(setenv "SHELL" shell-file-name) 
	(setq explicit-shell-file-name shell-file-name) 
	;;
	;; This removes unsightly ^M characters that would otherwise
	;; appear in the output of java applications.
	;;
	(add-hook 'comint-output-filter-functions
	          'comint-strip-ctrl-m)
@end example

If you want NT Emacs to understand Cygwin paths, get
cygwin-mount.el from @file{http://www.emacswiki.org/elisp/index.html}.

Note that all of this ``just works'' if you use the Cygwin port of
Emacs from Cygwin Setup.

@subsection What about XEmacs?

For a concise description of the current situation with XEmacs, see
this message from the Cygwin mailing list:
@file{http://cygwin.com/ml/cygwin/2002-11/msg00609.html}.

@subsection Is there a better alternative to the standard console window?

Yes!  Use rxvt instead.  It's an optional package in Cygwin Setup.
You can use it with or without X11.  You can resize it easily by
dragging an edge or corner.  Copy and paste is easy with the left and
middle mouse buttons, respectively.  It will honor settings in your
~/.Xdefaults file, even without X.

Don't invoke as simply ``rxvt'' because that will run /bin/sh (really
ash) which is not a good interactive shell.  For details see
@code{/usr/doc/Cygwin/rxvt-<ver>.README}.

@subsection info error "dir: No such file or directory"

Cygwin packages install their info documentation in the /usr/info
directory.  But you need to create a @code{dir} file there before the
standalone info program (probably @code{/usr/bin/info}) can be used to
read those info files.  This is how you do it:
@example
	bash$ cd /usr/info
	bash$ for f in *.info ; do install-info $f dir ; done
@end example
This may generate warnings:
@example
	install-info: warning: no info dir entry in `gzip.info'
	install-info: warning: no info dir entry in `time.info'
@end example
The @code{install-info} command cannot parse these files, so you will
have to add their entries to @code{/usr/info/dir} by hand.

Even if the dir file already exists, you may have to update it when
you install new Cygwin packages.  Some packages update the dir file
for you, but many don't.

@subsection Why do I get a message saying Out of Queue slots?

"Out of queue slots!" generally occurs when you're trying to remove
many files that you do not have permission to remove (either because
you don't have permission, they are opened exclusively, etc).  What
happens is Cygwin queues up these files with the supposition that it
will be possible to delete these files in the future.  Assuming that
the permission of an affected file does change later on, the file will
be deleted as requested.  However, if too many requests come in to
delete inaccessible files, the queue overflows and you get the message
you're asking about.  Usually you can remedy this with a quick chmod,
close of a file, or other such thing.  (Thanks to Larry Hall for
this explanation).

@subsection Why don't symlinks work on samba-mounted filesystems?

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:

@smallexample
	map system = yes
	create mask = 0775
@end smallexample

Note that the 0775 can be anything as long as the 0010 bit is set.

@subsection Why does df report sizes incorrectly.

There is a bug in the Win32 API function GetFreeDiskSpace that
makes it return incorrect values for disks larger than 2 GB in size.
Perhaps that may be your problem?

@subsection Why doesn't Cygwin tcl/tk understand Cygwin paths?

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 with the @samp{-mno-cygwin} option to @code{gcc}, which
means they do not understand Cygwin mounts or symbolic links.

See the entry "How do I convert between Windows and UNIX paths?"
elsewhere in this FAQ.