Fix bug #12829 with aborts on MS-Windows when several child processes die.

 nt/inc/sys/wait.h: New file, with prototype of waitpid and
 definitions of macros it needs.
 nt/inc/ms-w32.h (wait): Don't define, 'wait' is not used anymore.
 (sys_wait): Remove prototype.
 nt/config.nt (HAVE_SYS_WAIT_H): Define to 1.

 src/w32proc.c (create_child): Don't clip the PID of the child
 process to fit into an Emacs integer, as this is no longer a
 restriction.
 (waitpid): Rename from sys_wait.  Emulate a Posix 'waitpid' by
 reaping only the process specified by PID argument, if that is
 positive.  Use PID instead of dead_child to know which process to
 reap.  Wait for the child to die only if WNOHANG is not in
 OPTIONS.
 (sys_select): Don't set dead_child.
 src/sysdep.c (wait_for_termination_1): Remove the WINDOWSNT portion,
 as it is no longer needed.
 src/process.c (waitpid, WUNTRACED) [!WNOHANG]: Remove definitions,
 no longer needed.
 (record_child_status_change): Remove the setting of
 record_at_most_one_child for the !WNOHANG case.

1 files changed, 0 insertions, 20 deletions

diff --git a/src/process.c b/src/process.c
index 785282fba36..5fe6a6540f3 100644
--- a/src/process.c
+++ b/src/process.c
@@ -130,18 +130,6 @@ extern int sys_select (int, SELECT_TYPE *, SELECT_TYPE *, SELECT_TYPE *,
                        EMACS_TIME *, void *);
 #endif
 
-/* This is for DOS_NT ports.  FIXME: Remove this old portability cruft
-   by having DOS_NT ports implement waitpid instead of wait.  Nowadays
-   POSIXish hosts all define waitpid, WNOHANG, and WUNTRACED, as these
-   have been standard since POSIX.1-1988.  */
-#ifndef WNOHANG
-# undef waitpid
-# define waitpid(pid, status, options) wait (status)
-#endif
-#ifndef WUNTRACED
-# define WUNTRACED 0
-#endif
-
 /* Work around GCC 4.7.0 bug with strict overflow checking; see
    <http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52904>.
    These lines can be removed once the GCC bug is fixed.  */
@@ -6295,17 +6283,9 @@ record_child_status_change (pid_t pid, int w)
 {
 #ifdef SIGCHLD
 
-# ifdef WNOHANG
   /* On POSIXish hosts, record at most one child only if we already
      know one child that has exited.  */
   bool record_at_most_one_child = 0 <= pid;
-# else
-  /* On DOS_NT (the only porting target that lacks WNOHANG),
-     record the status of at most one child process, since the SIGCHLD
-     handler must return right away.  If any more processes want to
-     signal us, we will get another signal.  */
-  bool record_at_most_one_child = 1;
-# endif
 
   Lisp_Object tail;