[Bug libc/18433] New: posix_spawn does not return correctly upon failure to execute

["nachms+sourceware at gmail dot com" <sourceware-bugzilla at sourceware dot org>]

https://sourceware.org/bugzilla/show_bug.cgi?id=18433

            Bug ID: 18433
           Summary: posix_spawn does not return correctly upon failure to
                    execute
           Product: glibc
           Version: 2.19
            Status: NEW
          Severity: normal
          Priority: P2
         Component: libc
          Assignee: unassigned at sourceware dot org
          Reporter: nachms+sourceware at gmail dot com
                CC: drepper.fsp at gmail dot com
  Target Milestone: ---

posix_spawn is supposed to return a value indicating an error when it fails.
The specification for it is here:
http://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_spawn.html

>From the spec: Otherwise, no child process shall be created, the value stored
into the variable pointed to by a non-NULL pid is unspecified, and *an error
number shall be returned as the function return value* to indicate the error.

However, glibc is returning 0 (success) instead of some kind of indication of
error (such as 2 for ENOENT).

Test program:
-------------------------
#include <stdio.h>
#include <spawn.h>

int main()
{
  extern char **environ;
  char *argv[] = { "/bin/blah_blah-blah", 0 };
  pid_t pid = -1;
  int ret = posix_spawn(&pid, argv[0], 0, 0, argv, environ);
  printf("ret: %d\npid: %ld\n", ret, (long)pid);
  return(0);
}
-------------------------

"/bin/blah_blah-blah" doesn't exist, so it should not successfully spawn.

GLIBC for this program is returning:
ret: 0
pid: 17302

FreeBSD, DragonFlyBSD, NetBSD, and musl-libc all handle this correctly.
With them:
ret: 2
pid: -1 (some will put a different value here, which is allowed by the
standard)

-- 
You are receiving this mail because:
You are on the CC list for the bug.