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From: alan@lxorguk.ukuu.org.uk (Alan Cox)
Subject: Re: signal masks and select
To: leisner@sdsp.mc.xerox.com (Marty Leisner)
Date: Sat, 10 Feb 1996 22:58:35 +0000 (GMT)
Cc: paul@sfe.com.au, linux-kernel@vger.rutgers.edu, hackers@freebsd.org
In-Reply-To: <9602092033.AA14852@gnu.mc.xerox.com> from "Marty Leisner" at Feb 9, 96 12:33:45 pm
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> 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

Not the kernel, keep it out of the kernel. Put the setjmp one into a nice
libc routing called select_with_newmask and don't look too hard at it, it
works, its efficient and its n your libraries where it belongs. If you don't
like the setjmp code, rewrite the routine in a language with good exception
support ;)

Alan