Stdarg.h: What is it?

[Tom Boutell]

I'm attempting to compile a program with gnu cc under SunOS 4.0.3 on a
Sun-3. Most of the code compiles cleanly, but it fails while looking for
an include file named "stdarg.h". I take it this is some expected portion
of the standard Unix header files that either ain't there or has a
different name under SunOS? Any and all help appreciated. Please respond
by email as I don't normally read this newsgroup.