Assume at least POSIX.1-1988 for getpgrp, setpgid, setsid.

This removes code that has been obsolete since around 1990.
* admin/CPP-DEFINES (HAVE_SETPGID, HAVE_SETSID, SETPGRP_RELEASES_CTTY):
Remove; obsolete.
* configure.ac (setpgid, setsid): Assume their existence.
(AC_FUNC_GETPGRP, SETPGRP_RELEASES_CTTY): Remove; obsolete.
* src/callproc.c (Fcall_process):
* src/emacs.c (main):
* src/process.c (create_process):
* src/term.c (dissociate_if_controlling_tty):
Assume setsid exists.
* src/callproc.c (child_setup): Assume setpgid exists and behaves as
per POSIX.1-1988 or later.
* src/conf_post.h (setpgid) [!HAVE_SETPGID]: Remove.
* src/emacs.c (shut_down_emacs):
* src/sysdep.c (sys_suspend, init_foreground_group):
Assume getpgrp behaves as per POSIX.1-1998 or later.
* src/msdos.c (setpgrp): Remove.
(tcgetpgrp, setpgid, setsid): New functions.
* src/systty.h (EMACS_GETPGRP): Remove.  All callers now use getpgrp.
* src/term.c (no_controlling_tty): Remove; unused.
* src/w32proc.c (setpgrp): Remove.
(setsid, tcgetpgrp): New functions.

Fixes: debbugs:12800

1 files changed, 4 insertions, 0 deletions

diff --git a/ChangeLog b/ChangeLog
index 83026bc5065..e8bff20d56d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,9 @@
 2012-11-05  Paul Eggert  <eggert@cs.ucla.edu>
 
+        Assume at least POSIX.1-1988 for getpgrp, setpgid, setsid (Bug#12800).
+        * configure.ac (setpgid, setsid): Assume their existence.
+        (AC_FUNC_GETPGRP, SETPGRP_RELEASES_CTTY): Remove; obsolete.
+
         Simplify by assuming __fpending.
         Now that Emacs is using the gnulib fpending module,
         there's no need for Emacs to have a separate implementation.