RE: [Patch] Some more DOS compatibility

[Tim Van Holder]

> I don't recall the details, but I have kept this at hand.  Frankly, I
> don't want anything intelligent getting in 2.49d now.  Only brain
> stupid things, that makes no significant difference.  Understand that
> I will not change anything in this area before 2.50.
> 
> But rest assured, 2.51 will be quickly released (IMHO) afterwards.
No problem - I got no replies to my last question, so I simply asked
again :-)  There's no real rush, especially since fairly few packages use
sub-configures.

I would like to get one semi-intelligent thing into 2.50: a system
whereby a variable is checked for additional executable extensions to
try (in shell_path_walk and friends). That variable would not yet be
set by autoconf (such logic being delayed until 2.51 or later), but it
would make it easier for DJGPP-OS/2-... maintainers to provide extended
support by setting it in their respective config.site files.

I'd suggest something like:

if test -f dir/foo; then
  blah
elif test -n "$ac_executable_extensions"; then <-- usually never true
  for ac_ext in $ac_executable_extensions; do
    if test -f dir/foo$ac_ext; then
        blah
    fi
  done
fi

Then the djgpp package for autoconf could have a config.site with
        ac_executable_extensions=".exe .bat .btm .sh .pl .com"
and all (well, most) will be well (without the breakage added by test -x).