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Date: Tue, 28 Jul 2015 10:33:18 -0700
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Subject: Re: eventfd lookalike in FreeBSD ?
From: Adrian Chadd <adrian.chadd@gmail.com>
To: David Chisnall <theraven@freebsd.org>
Cc: Luigi Rizzo <rizzo@iet.unipi.it>,
 freebsd-current <freebsd-current@freebsd.org>
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On 28 July 2015 at 10:31, David Chisnall <theraven@freebsd.org> wrote:
> On 28 Jul 2015, at 18:23, Adrian Chadd <adrian.chadd@gmail.com> wrote:
>>
>> (What would be nice is having kqueue know about conditionals, so we
>> can sleep on a cond as well as a kqueue fd+queue, but I can't have
>> everything I want..)
>
> I recently came across a need to do something like this.  Being able to a=
dd condvar / mutex pairs to a kqueue and wait on a set of condition variabl=
es, reacquiring the mutexes for any of the signalled ones, as well as waiti=
ng for kernel events would be very useful.

Windows has had this for years. It makes async network programming
with thread worker queues significantly less abusive.


-adrian