Re: quotearg.c's shell_quoting_style and MinGW

On 05/06/2012 04:49 AM, Bruno Haible wrote:

> 1) Change the three locations in src/diff3.c, src/sdiff.c, src/util.c to
>     use the gnulib modules 'execute' and 'spawn-pipe'....

This would add (by my count) 72 source files to diff, and would
add some complexity to diffutils proper.  I'd rather keep things
simple if we can (my most recent change to diff was to *remove* a
gnulib module, yay! ...), or at least substitute a simpler set of
gnulib modules that would require less fiddling with diffutils
proper.

>       - If you apply these changes also to the HAVE_WORKING_FORK code branch,
>         it will speed up the subprocess invocation also on Unix, by
>         bypassing /bin/sh.

/bin/sh is already bypassed on Unix, since the code invokes execvp
or execl in that case, so I don't see how these changes would
benefit Unix performance.

The motivation for the existing code is to have something that is
simple and easy to understand in portable terms and works
efficiently on GNU and similar systems, and to do something
similar (though efficiency is less of a concern) on systems that
lack 'fork'.  These other systems include not just Microsoft
Windows, but also other platforms such as OpenVMS.

What about the other idea, to add gnulib support for popen and for
system to have them quote properly for mingw?  That would require
no changes to diffutils proper (other than a one-line addition to
bootstrap.conf) and would presumably need far fewer than 72 source
files.