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From: chris@umcp-cs.UUCP (Chris Torek)
Newsgroups: net.lang.c
Subject: Re:  Swap by name
Message-ID: <2293@umcp-cs.UUCP>
Date: Sun, 6-Jul-86 19:10:36 EDT
Article-I.D.: umcp-cs.2293
Posted: Sun Jul  6 19:10:36 1986
Date-Received: Mon, 7-Jul-86 02:21:09 EDT
References: <1964@brl-smoke.ARPA> <1060@umd5.UUCP>
Reply-To: chris@maryland.UUCP (Chris Torek)
Organization: University of Maryland, Dept. of Computer Sci.
Lines: 16

>In article <1964@brl-smoke.ARPA> rbj@icst-cmr.ARPA (Root Boy Jim) writes:
>>I was thinking of the caller squirrelling away the value in a temporary
>>location, passing it by reference (thus allowing modification by the
>>callee) and then copying the result to the real variable.

In article <1060@umd5.UUCP> zben@umd5.UUCP (Ben Cranston) replies:
>Of course the difference between this and real call-by-name comes when 
>the subroutine has an alternate access to the global in question - perhaps
>because of scoping rules, or access to a pointer-to-it or something.

Careful, Ben: this was under a section about call by value-result,
and it does accomplish that quite handily.
-- 
In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 1516)
UUCP:	seismo!umcp-cs!chris
CSNet:	chris@umcp-cs		ARPA:	chris@mimsy.umd.edu