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From: henry@utzoo.UUCP (Henry Spencer)
Newsgroups: net.lang.c
Subject: Re: var args
Message-ID: <3258@utzoo.UUCP>
Date: Sun, 16-Oct-83 00:15:33 EDT
Article-I.D.: utzoo.3258
Posted: Sun Oct 16 00:15:33 1983
Date-Received: Sun, 16-Oct-83 00:15:33 EDT
References: <3637@duke.UUCP>
Organization: U of Toronto Zoology
Lines: 11

How do you implement variable numbers of arguments in C?  In a word,
unportably.  (Is that a word?)  The implementation is fundamentally
machine-dependent.  There are portable "library" facilities for doing
it in some Unixes, but the insides of those libraries are still quite
machine-dependent.  Scanning a variable-length argument list requires
knowing the C calling sequence on the machine in question, so that you
know how the arguments are laid out in core.  Machines differ enough
on this point that machine-independent code for it is impossible.
-- 
				Henry Spencer @ U of Toronto Zoology
				{allegra,ihnp4,linus,decvax}!utzoo!henry