Re: [PATCH 6/9] difftool: replace system call with Git::command_noisy

[Alex Riesen <raa.lkml@gmail.com>]

On Sat, Mar 17, 2012 at 15:48, Tim Henigan <tim.henigan@gmail.com> wrote:
> On Sat, Mar 17, 2012 at 6:50 AM, Alex Riesen <raa.lkml@gmail.com> wrote:
>> On Sat, Mar 17, 2012 at 03:48, David Aguilar <davvid@gmail.com> wrote:
>>> Is this no longer a concern?  Does Git.pm need a similar portability
>>> caveat, or  does it avoid the problem altogether since it uses fork()
>>> + exec() + waitpid()?  (if this is true then it implies that this
>>> change is fine).
>
> I need to spend more time testing this.  On Windows, I have tested
> with msysgit but not cygwin.  Was ActiveState Perl used with cygwin
> git?

Yes, it is even stated in the commentary.

As far as I know, there is only one installation where a cygwin-compiled
Git is used with the ActiveState Perl (mine. I believe we would have
heard if there were others - it is an extremely annoying combination).

>> It _might_ work. Cygwin kind of has fork(2), it even works (kind of:
>> it is a *very* expensive thing to do). There are also other ifs and
>> whens, but it is worth a test. It's a nice clean up to have.
>
> Even it fork(2) is expensive, in this case it seems reasonable. Given
> the time needed to spawn the diff tool, the fork(2) time seems
> negligible.

Not Cygwin's fork. They really do a deep copy of parent process.

But actually, I misunderstood. The Perl used was of ActiveState origin.
So the code in question is not affected by Cygwin at all.
I have no idea how usable fork(2) of ActiveState Perl is.

Even if it is bad, I won't be really affected, I very seldom use the
difftool, and I believe I never used it on that particular system.

I try test the patch in the next days. I'll tell if something is
completely broken.