🚀 go-pugleaf

Is using the macro va_start more than once in a function legal in
ANSI C? I was thinking of something along the lines of:

#include <stdarg.h>

void two_pass_arg_eater(int first_arg, ...)
  {
    va_list ap;

    va_start(ap, first_arg);
    /* while ... va_arg(ap, type) ... process args pass 1 */
    va_end(ap);

    va_start(ap, first_arg);
    /* while ... va_arg(ap, type) ... process args pass 2 */
    va_end(ap);
  }

My trusty Harbison and Steele (3rd ed.) does not forbid it as far as I
can tell, but I'm looking for a more authoritative answer. I have not
tried it on any compilers, because a particular compiler's behavior is
not what I seek.

As I am sure I will hear about it anyway <g>, comments concerning the
advisability of this are also welcome, but are perhaps more appropriately
e-mailed to me directly, depending on their relevance to the group.

--
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Michael Keirnan                 | Internet: mgk@sybase.com
Sr. Software Engineer           | Voice: 617-238-6210
Sybase, Inc.                    | #include <legal/disclaimer.h>
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