alloca() is a PWBism, and was supplied with PWB/UNIX 1.0 and the USG UNIX
releases (including System III and System V), and is used by the SCCS code,
among other clients. It seems to have crossed the blood-brain barrier and
passed into Berkeley UNIX, along with so many other things...
Guy Harris
{seismo,mcnc,we13,brl-bmd,allegra}!rlgvax!guy