Article View: comp.std.unix
Article #677Re: qfork()
From: Barry Margolin
Date: Wed, 26 Dec 1990 22:54
Date: Wed, 26 Dec 1990 22:54
22 lines
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1554 bytes
Submitted-by: barmar@think.uucp (Barry Margolin)
In article <16213@cs.utexas.edu> jason@cnd.hp.com (Jason Zions) writes:
>Instead of replacing "executes any code", I think you could just add the
>phrase "which modifies memory or calls any function" and maintain the
>intent. Examining variables doesn't depend upon the virtual memory
>relationship between child and parent, but munging a stack for a function
>call might behave differently and hence must be rendered undefined.
Rather than "modifies memory" I suggest it be "modifies any variables" or
something like it that refers to high-level objects created by the C
program. Just examining a variable may modify memory; on a stack machine,
comparing a variable with zero generally requires pushing the variable onto
the stack, and even on a register machine loading the variable into a
register might force the register's old value to be written to memory.
--
Barry Margolin, Thinking Machines Corp.
barmar@think.com
{uunet,harvard}!think!barmar
Volume-Number: Volume 22, Number 41
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Path: arc1-ca.pugleaf.net!utzoo!utgpu!news-server.csri.toronto.edu!rutgers!cs.utexas.edu!jsq From: barmar@think.uucp (Barry Margolin) Newsgroups: comp.std.unix Subject: Re: qfork() Message-ID: <16244@cs.utexas.edu> Date: 26 Dec 90 22:54:50 GMT References: <16066@cs.utexas.edu> <16213@cs.utexas.edu> Sender: jsq@cs.utexas.edu Organization: Thinking Machines Corporation, Cambridge MA, USA Lines: 22 Approved: jsq@cs.utexas.edu (Moderator, John S. Quarterman) X-Submissions: std-unix@uunet.uu.net