bug#10074: 23.2; emacs rgrep on Windows/Cygwin: FIND: Parameter format not correct

[Xah Lee <xahlee@gmail.com>]

This seems to be a bug. Steps to reproduce:

• Start GNU Emacs with -Q.

• call “rgrep”. Search for anything.

• You get the following result:

──────────────────────────────
-*- mode: grep; default-directory: "c:/Users/h3/web/xahlee_org/emacs/" -*-
Grep started at Thu Nov 17 00:49:37

find . "(" -path "*/SCCS" -o -path "*/RCS" -o -path "*/CVS" -o -path
"*/MCVS" -o -path "*/.svn" -o -path "*/.git" -o -path "*/.hg" -o -path
"*/.bzr" -o -path "*/_MTN" -o -path "*/_darcs" -o -path "*/{arch}" ")"
-prune -o "(" -name ".#*" -o -name "*.o" -o -name "*~" -o -name
"*.bin" -o -name "*.bak" -o -name "*.obj" -o -name "*.map" -o -name
"*.ico" -o -name "*.pif" -o -name "*.lnk" -o -name "*.a" -o -name
"*.ln" -o -name "*.blg" -o -name "*.bbl" -o -name "*.dll" -o -name
"*.drv" -o -name "*.vxd" -o -name "*.386" -o -name "*.elc" -o -name
"*.lof" -o -name "*.glo" -o -name "*.idx" -o -name "*.lot" -o -name
"*.fmt" -o -name "*.tfm" -o -name "*.class" -o -name "*.fas" -o -name
"*.lib" -o -name "*.mem" -o -name "*.x86f" -o -name "*.sparcf" -o
-name "*.fasl" -o -name "*.ufsl" -o -name "*.fsl" -o -name "*.dxl" -o
-name "*.pfsl" -o -name "*.dfsl" -o -name "*.p64fsl" -o -name
"*.d64fsl" -o -name "*.dx64fsl" -o -name "*.lo" -o -name "*.la" -o
-name "*.gmo" -o -name "*.mo" -o -name "*.toc" -o -name "*.aux" -o
-name "*.cp" -o -name "*.fn" -o -name "*.ky" -o -name "*.pg" -o -name
"*.tp" -o -name "*.vr" -o -name "*.cps" -o -name "*.fns" -o -name
"*.kys" -o -name "*.pgs" -o -name "*.tps" -o -name "*.vrs" -o -name
"*.pyc" -o -name "*.pyo" ")" -prune -o  -type f "(" -iname "*" -o
-iname ".*" ")" -exec grep -i -n "grep" {} NUL ";"
FIND: Parameter format not correct

Grep exited abnormally with code 2 at Thu Nov 17 00:49:37
──────────────────────────────

GNU Emacs 23.2.1 (i386-mingw-nt6.1.7601) of 2010-05-08 on G41R2F1
Windowing system distributor `Microsoft Corp.', version 6.1.7601
configured using `configure --with-gcc (3.4) --no-opt --cflags -Ic:/xpm/include'

I'm also running Cygwin for the unix util grep.

It appears, that the problem is because emacs is calling cmd.exe's
grep, not cygwin. Perhaps `grep-compute-defaults' should know about
it.

 Xah