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To: Paul Hatchman <paul@sfe.com.au>
Cc: linux-kernel@vger.rutgers.edu, hackers@freebsd.org
Subject: Re: signal masks and select 
In-Reply-To: Your message of "Tue, 30 Jan 1996 23:49:00 PST."
             <199601310749.AA28625@rex.sfe.com.au> 
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Date: Fri, 9 Feb 1996 12:33:45 PST
From: "Marty Leisner" <leisner@sdsp.mc.xerox.com>
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Thanks for the help...

I liked this solution for now...
> 
> This can be "solved" by using setjmp/longjmp with select.
> ie 
> 	if (setjmp (env, 1) == 0)
> 	{
> 		set_sigmask(unblock desired signals)
> 		select(...)
> 	}
> 
> and your signal handler does a longjmp (env)
> 

But this is a kludgey workaround...and using pthreads (where each thread
has a signal mask) means env becomes thread private data...

It seems very reasonable to have a system call:
	select_with_newmask(new_mask, <old select parameters

-- 
marty
leisner@sdsp.mc.xerox.com  
Member of the League for Programming Freedom