Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!ncrlnk!ncrstp!npdiss1!mercer
From: mercer@npdiss1.StPaul.NCR.COMDan Mercer)
Newsgroups: comp.lang.c
Subject: Re: printf vs. vprintf
Message-ID: <162@npdiss1.StPaul.NCR.COM>
Date: 15 Aug 90 17:27:35 GMT
References: <1990Aug10.120048.28576@uni-paderborn.de> <411.26c40096@astro.pc.ab.com>
Reply-To: mercer@npdiss1.StPaul.NCR.COM (Dan Mercer)
Distribution: comp
Organization: StPaul
Lines: 34

In article <411.26c40096@astro.pc.ab.com> browns@astro.pc.ab.com (Stan Brown, Oak Road Systems) writes:
:In article <1990Aug10.120048.28576@uni-paderborn.de>, fillg1@uni-paderborn.de (Michael Illgner) writes:
:> Can anyone describe the advantages (or disadvantages) in using
:> vprintf instead of printf?
:
:I've never used vprintf, and I've been Cing for 7 years now!  (Jean-Pierre,
:grand-pere has passed 93 happy years in Choiseul-sur-Mer without once using the
:past anterior verb form. --New Yorker cartoon :-) )
:
:But seriously: If you have written a function that takes a variable number of
:arguments, and inside the function you want to printf those arguments, or all of
:them after the first so many, you would call vprintf to do it.  vprintf takes
:exactly two arguments, a char* for the format, and a va_list containing the
:other arguments.  That's the only usse I know for vprintf.
:
:So at the risk of oversimplifying: always use printf.  vprintf is used only in
:very special circumstances, which you're not likely to meet.
:
:Stan Brown, Oak Road Systems, (216) 371-0043
:The opinions expressed are mine. Mine alone!  Nobody else is responsible for
:them or even endorses them--except my cat Dexter, and he signed the power of
:attorney only under my threat to cut off his Cat Chow!

He's absolutely correct.  I wrote a menuing system.  I wanted to make
it as easy to use as printf,  so I wrote a wprintf function (window
print).  I use vsprintf to print the string into a buffer,  then
parsed the buffer for %B (bold) %N (normal) %R (reverse) and
%D (dim) directives replacing them with the correct terminal sequences.
That's the only time I ever used the va_args capability.
-- 

Dan Mercer
Reply-To: mercer@npdiss1.StPaul.NCR.COM (Dan Mercer)
"MAN - the only one word oxymoron in the English Language"