> As mentioned earlier on linux-kernel, Linux discards any pending
> SIGCHLD signals when a process calls one of the wait() functions.
> I don't know of any other unix that does this, so I hereby
> propose a patch that will bring Linux back in sync (hopefully :).
> *** kernel/exit.c.orig Mon Jun 3 11:26:38 1996
> --- kernel/exit.c Thu Jun 27 14:39:08 1996
> ***************
> *** 668,674 ****
> goto end_wait4;
> current->state=TASK_INTERRUPTIBLE;
> schedule();
> - current->signal &= ~(1<<(SIGCHLD-1));
> retval = -ERESTARTSYS;
> if (current->signal & ~current->blocked)
> goto end_wait4;
> --- 668,673 ----
I think pending SIGCHLD signals should be discarded if the signal handler
is SIG_IGN. Otherwise, do_signal will just end up reinvoking sys_wait4,
which won't necessarily hurt, but is a waste of time.
Marc.
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| Marc Aurele La France | work: 1-403-492-9310 |
| Computing and Network Services | fax: 1-403-492-1729 |
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