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From: John Birrell <cimaxp1!jb@werple.net.au>
Subject: Re: int type in jmpbuf
To: terry@lambert.org (Terry Lambert)
Date: Tue, 21 Nov 1995 10:10:53 +1100 (EST)
Cc: hackers@FreeBSD.org, jb@cimlogic.com.au
In-Reply-To: <199511202141.OAA02182@phaeton.artisoft.com> from "Terry Lambert" at Nov 20, 95 02:41:23 pm
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> Actually, the occurance of a signal condittion give you the _opportunity_
> to set a flag.

But not necessarily an opportunity to _check_ the flag.

> 
> Then you check the flag on a blocking call *not* in the signal handler
> before actually making the call to decide to do the context switch, and
> the problem goes away.

But if the running thread is not about to do any blocking calls, then it
can only be preempted by making a decision in the signal handler. The signal
handler has to perform the context switch. How else can we time slice between
two threads each doing while(1); ??

> 
> 
> 					Terry Lambert
> 					terry@lambert.org
> ---
> Any opinions in this posting are my own and not those of my present
> or previous employers.
> 


-- 
John Birrell                                CIMlogic Pty Ltd
jb@cimlogic.com.au                          119 Cecil Street
Ph  +61  3 9690 9600                        South Melbourne Vic 3205
Fax +61  3 9690 6650                        Australia
Mob +61 18  353  137