Actually, that qsort definition is straight out of the ANSI standard.
Ditto malloc.  You may have used SunOS; they have the world's *least*
standard system.  When ANSI standardized C, they standardized the "void"
type, and as a result, malloc() started returning (void *).  It had done
this on some systems before, AFAIR, but not on all...

sys_errlist is *not* an official interface; there is no excuse for code
to use it, as strerror() is just as good, if not better.

I have no idea what difference you're seeing with wait3().  I can tell you
that "our" qsort and malloc are as standard as anything gets.

-s