Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sdd.hp.com!decwrl!lll-winken!quintro!bpdsun1!dwg
From: dwg@bpdsun1.uucp (David W. Glessner)
Newsgroups: comp.os.msdos.programmer
Subject: Re: TC++ coroutines with setjmp/longjmp. (MSC)
Message-ID: <1990Sep11.211609.23889@bpdsun1.uucp>
Date: 11 Sep 90 21:16:09 GMT
References: <1727@dinl.mmc.UUCP> <1990Sep10.234937.12444@ecn.purdue.edu>
Reply-To: dwg@bpdsun1.UUCP (David W. Glessner)
Organization: Harris Broadcast Div., Quincy, IL
Lines: 17

In article <1990Sep10.234937.12444@ecn.purdue.edu> milton@zebra.ecn.purdue.edu (Milton D Miller) writes:
> [ stuff about setjmp/longjmp for multi-tasking kernel ]

>(BTW, supposedly the MSC 6.? manual says the Setjmp/Longjmp don't
>save enough state to be used for this purpose)

MSC 5.1 setjmp() does _not_ save enough state.  Specificially SS, ES,
and flags.  Multiple "processes" with their own stack (e.g. possibly from
malloc()) will also confuse the run-time stack checking routine __chkstk.

I'm not sure about MSC 6.0.

I've ported parts of KA9Q's NOS to MSC and have modified setjmp(),
longjmp(), and __chkstk to work properly.  E-mail for the gory details.
--
David	WU9A	quintro!bpdsun1!dwg@lll-winken.llnl.gov
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