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From: mazer@bek-owl.caltech.edu (Jamie Mazer)
Newsgroups: comp.unix.wizards
Subject: varargs question
Summary: va_alist
Keywords: varargs vsprintf
Message-ID: <11286@cit-vax.Caltech.Edu>
Date: 15 Jul 89 23:38:55 GMT
Sender: news@cit-vax.Caltech.Edu
Reply-To: mazer@bek-owl.caltech.edu (Jamie Mazer)
Distribution: usa
Organization: California Institute of Technology
Lines: 26

Recently, I have found I needed something like the C++ form
function (I believe this came up pretty recently in another
list as well). Our masscomp libs don't have vsprintf() etc, so
as a kludge, I first tried to cobble something together along
the lines of:
	format(a1, a2, a3, ... , a10)    /* ugly, but it often works ;-) */
	  char *a1, *a2, *a3, ... , *a10)
	{ ... sprintf(buf, a1, a2, a3, ... , a10); return(buf) ... }

However, then someone suggested I try the following solution:
	format(va_alist)
	  va_dcl
	{ ... sprintf(buf, va_alist); return(buf); ... }

The question is, is the second method a valid one? It seems to
work on our SUNs, but not reliably on the Masscomp, though for
the life of me, I can't figure out where and when it blows up.

Is it legit to pass va_alist into another function like that?
If so, then why are the vprintf() functions necessary at all?

Thanks,
/Jamie
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