bug#8265: 24.0.50; windows emacs hanging calling svn

[Eli Zaretskii <eliz@gnu.org>]

> From: Sam Steingold <sds@gnu.org>
> Cc: 8265@debbugs.gnu.org
> Mail-Copies-To: never
> Reply-To: sds@gnu.org
> Date: Wed, 16 Mar 2011 19:00:53 -0400

(Aren't Mail-Copies-To and Reply-To above in contradiction?)

> > * Eli Zaretskii <ryvm@tah.bet> [2011-03-17 00:08:06 +0200]:
> >
> >> Debugger entered--Lisp error: (error "Running svn status -v foo.cpp...FAILED (status 1)")
> >
> > I don't use svn; what kind of text is that command supposed to output?
> > E.g., what does it show if you run it from the command prompt under
> > the same conditions?
> 
> for a modified file:
> --------------------------
> M            11693    11346 sds          foo/bar/baz.h
> --------------------------
> for an unmodified file:
> --------------------------
>              11693     9843 sds         foo/bar/baz.h
> --------------------------

If it's a single line, it could be that Emacs doesn't see it due to
the fact that (I think) Windows pipes are buffered.  Or maybe it's a
decoding issue.  Can you trace through vc-do-command and see if Emacs
is invoking svn asynchronously or synchronously, and perhaps also
where it hangs?

> > Also, can you run this under Cygwin's strace and show the system call
> > where it (whatever "it" means) hangs?
> 
> when I try to attach strace or gdb to the svn process, they hang too.

That's not what I had in mind.  I would create an svn shell script,
with the following contents:

#!/bin/sh
strace -o svn.trace /cygdrive/path/to/svn/svn.exe $*

then make it appear in PATH before svn.exe, and then repeat whatever
you do in Emacs that hangs.  Hopefully, svn.trace will then show in
which syscall svn hangs, if it does.

the above is 100% untested, and also I have no idea about your setup
wrt shell and Cygwin, so you will probably need to tailor it.  But I
hope you get the idea.

> please let me know if I could do anything else, but I would appreciate
> _detailed_ instructions on any operation with visual studio.

Sorry, I don't use VS except occasionally, and only if I absolutely
have to.  I hope the above script will resolve the problem nicely.