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Date: Thu, 20 Sep 2001 10:38:06 -0700 (PDT)
From: John Baldwin <jhb@FreeBSD.org>
To: Nate Williams <nate@yogotech.com>
Subject: Re: sigsuspend() and KSE
Cc: arch@FreeBSD.ORG, julian@FreeBSD.ORG
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On 19-Sep-01 Nate Williams wrote:
>> /*
>>  * Suspend process until signal, providing mask to be set
>>  * in the meantime.  Note nonstandard calling convention:
>>  * libc stub passes mask, not pointer, to save a copyin.
>>  ***** XXXKSE this doesn't make sense under KSE.
>>  ***** Do we suspend the thread or all threads in the process?
>>  ***** How do we suspend threads running NOW on another processor?
>>  */
>> 
>> Here's my opinion:
>> 
>> sigsuspend() just suspends the current thread.  When a signal is posted, it
>> wakes up all threads blocked on sigsuspend whose mask matches that signal. 
>> I
>> can see it still making sense, but perhaps being of limited usefulness in a
>> threaded program.
> 
> What has limited usefulness?  Being able to suspend all threads, or
> waking up all threads?

I'm not sure you would use sigsuspend in the same way in threaded programs, but
perhaps I'm wrong.  I suppose it also depends on what threading model you are
using.

> Nate

-- 

John Baldwin <jhb@FreeBSD.org> -- http://www.FreeBSD.org/~jhb/
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