From:	Hans-Bernhard Broeker <broeker AT physik DOT rwth-aachen DOT de>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: va_list args
Date:	31 Jan 2001 14:48:34 GMT
Organization:	Aachen University of Technology (RWTH)
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Christian Merz <cmerz AT bndlg DOT de> wrote:
> can anybody tell me how the va_list, va_start() and va_end() works? 

Unless you want to re-implement them on your own, in assembly or so,
you don't need to know how they work. Just how you're supposed to use
them.

> I have to include the "<stdarg.h>" file, because I'll write my own
> printf function for my os, but I guess va_list, va_start() and
> va_end() uses some memory allocation routines for allocating some
> lists and so on , right?

No memory allocation, no. The arguments have been put on the stack by
the calling function. All va_start() and friends to is hand them over
to your code, one by one.

> So what I have to do to get the "va" stuff working?

Just use them. They already do work --- if they don't, you're not done
yet with porting GCC to that OS :-)

	info libc alpha varargs

has all you need to know, I think.
-- 
Hans-Bernhard Broeker (broeker AT physik DOT rwth-aachen DOT de)
Even if all the snow were burnt, ashes would remain.

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