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From: peter@ficc.uu.net (Peter da Silva)
Newsgroups: comp.lang.c
Subject: Re: threads for C/C++ under Unix?
Message-ID: <6486@ficc.uu.net>
Date: 9 Oct 89 21:43:37 GMT
References: <12298@polya.Stanford.EDU>
Reply-To: peter@ficc.uu.net (Peter da Silva)
Organization: Xenix Support, FICC
Lines: 28

In article <12298@polya.Stanford.EDU> hall@eclipse.stanford.edu (Keith Hall) writes:
>   1.  Does a portable preemptive thread package for Unix, such as
>       described above, exist?

There isn't even a portable non-preemptive threads package. There isn't
even a co-routine package.

>   2.  Is there a reason such a package cannot be written without
>       kernel modifications?

Your quantum would be rather large in most implementations (1 second
for alarm()). Non-preemptive threads could be implemented without any
changes even for systems less powerful than UNIX.

>   3.  If kernel mods are required, why haven't we programmer's
>       demanded that they be done?  Put another way, is the utility
>       of threads not generally recognized?

(a) I don't know. (b) The utility of threads is unrecognised.

I have occasionally tried to drum up some interest in non-preemptive
threads (a whole lot easier to implement -- and safer), with little
success. I wish you luck.
-- 
Peter da Silva, *NIX support guy @ Ferranti International Controls Corporation.
Biz: peter@ficc.uu.net, +1 713 274 5180. Fun: peter@sugar.hackercorp.com. `-_-'
                                                                           'U`
Quote: Structured Programming is a discipline -- not a straitjacket.