bug#17561: Emacs can forget processes

[Andreas Schwab]

Paul Eggert <eggert@cs.ucla.edu> writes:

>> 13:28:46 kill(4294962889, SIGKILL)      = 0 <0.002883>
>> 13:28:46 --- SIGIO (I/O possible) @ 0 (0) ---
>> 13:28:46 rt_sigreturn(0x1d)             = 0 <0.000021>
>> 13:28:46 rt_sigprocmask(SIG_SETMASK, [QUIT ALRM CHLD PROF], NULL, 8) = 0 
>> <0.000016>
>> 13:28:46 ioctl(3, FIONREAD, [0])        = 0 <0.000018>
>> 13:28:46 rt_sigprocmask(SIG_BLOCK, [CHLD], [QUIT ALRM CHLD PROF], 8) = 0 
>> <0.000017>
>> 13:28:46 kill(4294962889, SIGHUP)       = 0 <0.000017>
>
> I'm surprised by the above trace.  The first kill(-4407,SIGKILL) succeeds,
> indicating that Emacs still has a subprocess.  But Emacs doesn't get a
> SIGCHLD, even after it unblocks SIGCHLD.

Nothing in that sequence unblocks SIGCHLD.

Andreas.

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Andreas Schwab, schwab@linux-m68k.org
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