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From: Nobody <nobody@nowhere.com>
Subject: Re: Safe accesses of global arrays in signal handlers?
Date: Sun, 30 Sep 2012 20:46:24 +0100
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On Sun, 30 Sep 2012 13:12:27 +0200, Markus Elfring wrote:

>> The signal handler only needs to write one byte at a time;
>> the receiving thread can read a pipe-full at a time. If the receiving
>> thread does nothing but notify worker threads or enqueue messages,
>> there shouldn't be a problem.
> 
> Is it a software design challenge to forward the number that was passed
> to this callback function into the dedicated pipe?

Using a pipe is fine if you just want to wake a thread when something
interesting has happened, but if you're trying to turn signals into
events, the sigwaitinfo() approach is the way to go.