[RP] [PATCH] tmpwm fix: SIG_IGN -> SIG_DFL

[Jérémie Courrèges -Anglas]

Hi ratpoison lovers,

here attached is a patch to fix the behaviour of tmpwm on OpenBSD and
probably other OSes where semantics of signal(SIGCHLD, SIG_IGN) are
different from GNU/Linux.  Quoting the OpenBSD signal(3) manpage:

     If the func is set to SIG_IGN for the SIGCHLD signal, the system will not
     create zombie processes when children of the calling process exit.  If
     the calling process subsequently issues a wait(2) (or equivalent), it
     blocks until all of the calling process's child processes terminate, and
     then returns a value of -1 with errno set to ECHILD.  This differs from
     historical BSD behavior but is consistent with AT&T System V UNIX as well
     as the X/Open Portability Guide Issue 4, Version 2 (``XPG4.2'').

I see no reason for this patch to introduce a regression on other
platforms, and testing on Debian Squeeze show no difference in
behaviour.

BTW, the random bug related to tmpwm doesn't seem to be fixed.  Since
I couldn't reproduce it with anything but ''newwm ratpoison'', I'd say
that's not a really big problem. :)

-- 
Jérémie Courrèges-Anglas
GPG Key fingerprint: 61DB D9A0 00A4 67CF 2A90  8961 6191 8FBF 06A1 1494

From 343b19f653a7f8455e8d1aea7594e5b660e3c2ac Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?J=C3=A9r=C3=A9mie=20Courr=C3=A8ges-Anglas?= <address@hidden>
Date: Thu, 13 Dec 2012 14:27:54 +0100
Subject: [PATCH] tmpwm fix: SIG_IGN -> SIG_DFL

for signal(SIGCHLD, SIG_IGN) behaves wildly differently across OSes. Fixes
tmpwm hanging after child wm exits on OpenBSD.
---
 src/actions.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/actions.c b/src/actions.c
index bf381c8..8559585 100644
--- a/src/actions.c
+++ b/src/actions.c
@@ -4758,7 +4758,7 @@ cmd_tmpwm (int interactive UNUSED, struct cmdarg **args)
   XSync (dpy, False);
 
   /* Disable our SIGCHLD handler */
-  set_sig_handler (SIGCHLD, SIG_IGN);
+  set_sig_handler (SIGCHLD, SIG_DFL);
   /* Launch the new WM and wait for it to terminate. */
   pid = spawn (ARG_STRING(0), 0, NULL);
   PRINT_DEBUG (("spawn pid: %d\n", pid));
-- 
1.8.0.1

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