Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ames!haven!adm!smoke!gwyn
From: gwyn@smoke.BRL.MIL (Doug Gwyn )
Newsgroups: comp.lang.c
Subject: Re: varargs and scanf
Keywords: vfprintf, ANSI C,...
Message-ID: <9553@smoke.BRL.MIL>
Date: 1 Feb 89 22:25:30 GMT
References: <1494@zen.UUCP>
Reply-To: gwyn@brl.arpa (Doug Gwyn (VLD/VMB) <gwyn>)
Organization: Ballistic Research Lab (BRL), APG, MD.
Lines: 24

In article <1494@zen.UUCP> vic@zen.UUCP (Victor Gavin) writes:
>The function I was creating required two obligatory parameters and the rest
>were optional. The function was declared
>	void foo(va_alist)

I think you mean that was the declaration used in the function definition?
That's not ANSI C in any case.  For ANSI C you must use the ",..." form of
declaration/definition for varargs functions.  va_alist belongs to the old
<varargs.h>, not ANSI C and <stdarg.h>.

>My problem was that to catch any mistakes in programs which call it I used
>the prototype
>	extern void foo(int,int,...);

That's okay.  Fix the function definition to have the same shape.

>My other problem is that there isn't a varargs version of scanf(). Is there
>one in ANSI C or is it something that only I would find useful?

No, v*scanf() are not in the proposed ANSI C Standard.  In fact there
was considerable sentiment for removing the normal *scanf() functions.

I'm not sure how useful v*scanf() would be; I've never felt the need
for it, though.