bug#4867: 23.1; dired cannot find gunzip with Z; Windows

[Xah Lee]

when using emacs on Windows, when in dired, when i press Z on a file that's 
gzip compressed, emacs tells me:
'gunzip' is not recognized as an internal or external command,

the problem is apparently that emacs won't recognize the gunzip shell script 
without the exe suffix. (the gunzip is in the same dir as gzip.exe) But if i 
rename gunzip to gunzip.exe, but Windows complain that the file is not a exe 
format.

extra detail:

when i do
(executable-find "gzip")
emacs says
"c:/cygwin/bin/gzip.exe"

and
(executable-find "gunzip")
says
nil.

the gunzip exists at
c:/cygwin/bin/gunzip
which is a shell script that calls gzip -d.

Same problem when starting emacs with -Q.

GNU Emacs 23.1.1 (i386-mingw-nt6.0.6002) of 2009-07-29 on SOFT-MJASON

---------

I'm reporting this as a bug, but tips on solving this on my machine also 
would be appreciated. Thank you.

I'm thinking, shouldn't emacs's dired simply look for gzip and call it with 
gzip -d, instead of looking for the gunzip program? That seems to me simpler 
and more reliable.

 Xah
∑ http://xahlee.org/

☄