Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!apple!usc!basil.usc.edu!blarson
From: blarson@basil.usc.edu (bob larson)
Newsgroups: comp.std.c
Subject: Re: how to exit from a signal routine
Keywords: ANSI, longjmp, signal
Message-ID: <18302@usc.edu>
Date: 7 Jul 89 00:49:43 GMT
References: <7997@cbnews.ATT.COM>
Sender: news@usc.edu
Reply-To: blarson@basil.usc.edu (bob larson)
Organization: USC AIS, Los Angeles
Lines: 19

In article <7997@cbnews.ATT.COM> mark@cbnews.ATT.COM (Mark Horton) writes:
>Is there
>any conceivable implementation of longjmp that will have problems
>when it gets called 1 1/2 times?

On the Prime 50 series, longjump includes backtracking through the
stack for cleanup$ condition handlers (none will be present in
portable C) and for restoring registers.  I don't think longjump from
within longjump would cause problems unless your cleanup$ condition
handler was non-reentrant, but I wouldn't guarentee this.

Also, you would have to guarentee your second longjump call would have
to be to the same or an earlier level, or you could have a real mess.

-- 
Bob Larson	Arpa:	blarson@basil.usc.edu
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