Hi Paul,
> note that
> on Windows, which is the only place this matters, so far, IIRC it is
> illegal to use "prog.exe.exe" so if an extension is already provided
> the system won't search again
Indeed, the native Windows execlp() function behaves like this:
- If the caller specifies "prog.exe.exe" or "prog.foo.exe" and
that file will be exists, it will be found and executed.
- If the caller specifies "prog.exe" or "prog.foo" but that file
does not exist, the search will NOT extend to "prog.exe.exe" or
"prog.foo.exe", respectively.
I'm updating the code (patch below).
> I actually don't see any need for this optimization, especially
> compared to the added complexity of the API and docs: the suffix check
> needs to be done somewhere after all.
But on platforms like Cygwin, it would be done twice.
2019-09-14 Bruno Haible <br...@clisp.org>
findprog-in: Better mimic the system on native Windows.
Reported by Paul Smith <psm...@gnu.org>.
* lib/findprog-in.c (find_in_given_path): On native Windows, don't try
non-empty suffixes when the file name already contains a '.'.
diff --git a/lib/findprog-in.c b/lib/findprog-in.c
index 99b3c31..d601e06 100644
--- a/lib/findprog-in.c
+++ b/lib/findprog-in.c
@@ -118,8 +118,9 @@ find_in_given_path (const char *progname, const char *path,
const char *suffix = suffixes[i];
#if defined _WIN32 && !defined __CYGWIN__ /* Native Windows */
- /* File names without a '.' are not considered executable. */
- if (*suffix != '\0' || strchr (progbasename, '.') != NULL)
+ /* File names without a '.' are not considered executable, and
+ for file names with a '.' no additional suffix is tried. */
+ if ((*suffix != '\0') != (strchr (progbasename, '.') != NULL))
#endif
{
/* Concatenate progname and suffix. */
@@ -185,8 +186,9 @@ find_in_given_path (const char *progname, const char *path,
const char *suffix = suffixes[i];
#if defined _WIN32 && !defined __CYGWIN__ /* Native Windows */
- /* File names without a '.' are not considered executable. */
- if (*suffix != '\0' || strchr (progname, '.') != NULL)
+ /* File names without a '.' are not considered executable, and
+ for file names with a '.' no additional suffix is tried. */
+ if ((*suffix != '\0') != (strchr (progname, '.') != NULL))
#endif
{
/* Concatenate dir, progname, and suffix. */
