#defines with variable # arguments

[Guy Harris]

>     Are there any versions of cpp which allow one to define macros which
> accept variable numbers of arguments?

None that I know of.  There are tricks that can be used for this:

#define	Sprintf(x)	sprintf x

main()
{
	char buf[40];

	Sprintf((buf, "%d", 33));
	Sprintf((buf, "%d %d", 33, 66));
}

but this requires the extra layer of parentheses; I presume you want a
"magic bullet" that requires few source changes to the program you're trying to
convert.

Neither K&R nor ANSI C have any syntax for macros of this sort.

> I keep wishing for this every time I try to move code developed using sysV
> sprintf to a BSD system,

Your best bet here is just to redo the code not to depend on the return value
of "sprintf".  Sad, but true.

>     Does anyone know why the folks at Berkeley chose to have their
> sprintf return its first argument, instead of the number of characters
> printed?

Nobody can possibly know that, because they weren't the ones who made that
decision.  "sprintf" worked that way in V7 (although I don't think it was so
documented) - in fact, the System III SCCS code was written assuming this
behavior, which is kind of amusing since the System III "sprintf" returned the
number of characters generated....  (Some BSD/S5 differences are really V7/S5
differences; questions about why *those* differences exist should be directed
to AT&T, since they were responsible for both systems.)