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From: Markus Elfring <Markus.Elfring@web.de>
Newsgroups: comp.programming.threads,comp.unix.programmer
Subject: Re: Safe accesses of global arrays in signal handlers?
Date: Sat, 29 Sep 2012 13:44:50 +0200
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Xref: csiph.com comp.programming.threads:1119 comp.unix.programmer:3377

> Yes. write() is async-signal-safe, so one thread can do a blocking read()
> and the signal handler can use write() to wake it.

Thanks for your feedback.

Do you see any difficulties or software design challenges for proper handling of
the situation that more data is written into the pipe than the receiving thread
can read and process in a timely manner?


> Lock-free algorithms require memory semantics beyond those specified in
> the C and POSIX standards. E.g. they typically require the use of a memory
> barrier (fence).

I hope that the support for this use case will be improved by the current (and
following) standard version for the programming languages C and C++.
http://en.wikipedia.org/wiki/C++11#Threading_facilities

Regards,
Markus