Re: posible bug in daemontools

On Sun, Mar 14, 2010 at 1:17 AM, Jan Mojžíš <[email protected]> wrote:
> When is system out of memory, and some service (dnscache) is killed by OOM or die and
> supervise than fails to fork new process, supervise never start dnscache.

Indeed, supervise.c doesn't appear to correctly handle restarting the
monitored process if fork(2) fails.

> Did anyone see same problem or am I first?

I haven't heard of this problem before, and Google doesn't turn up
anything interesting.

> This patch  FIX my problem, but I'm not sure if it is correct way to solve this problem.

I think your patch is fine.  I would probably do this instead, though:

--- supervise.c~	2001-07-12 09:49:49.000000000 -0700
+++ supervise.c	2010-03-14 03:29:08.000000000 -0700
@@ -148,11 +148,12 @@
 	pidchange();
 	announce();
 	if (flagexit) return;
-	if (flagwant && flagwantup) trystart();
 	break;
       }
     }

+    if (flagwant && flagwantup && !pid) trystart();
+
     if (read(fdcontrol,&ch,1) == 1)
       switch(ch) {
 	case 'd':