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Groups > gnu.bash.bug > #15962

Re: "wait" loses signals

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From Chet Ramey <chet.ramey@case.edu>
Newsgroups gnu.bash.bug
Subject Re: "wait" loses signals
Date Mon, 24 Feb 2020 11:23:35 -0500
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Cc chet.ramey@case.edu, Denys Vlasenko <dvlasenk@redhat.com>, Harald van Dijk <harald@gigawatt.nl>, bug-bash@gnu.org
To Daniel Colascione <dancol@dancol.org>, Robert Elz <kre@munnari.OZ.AU>
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On 2/24/20 7:58 AM, Daniel Colascione wrote:

> No, it's not that much trouble to fix the bug. The techniques for fixing
> this kind of signal race are well-known. In particular, instead of
> waitpid, you use a self-pipe and signal the pipe in the signal handler,
> and you have a signal handler for SIGCHLD. 

You've just substituted a real IPC mechanism (pipes) for the one people
are trying to make signals into.

-- 
``The lyf so short, the craft so long to lerne.'' - Chaucer
		 ``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, UTech, CWRU    chet@case.edu    http://tiswww.cwru.edu/~chet/

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Re: "wait" loses signals Chet Ramey <chet.ramey@case.edu> - 2020-02-24 11:23 -0500

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