This directory contains the files that tailor upas to the different
flavors of UNIX on which it runs. It is meant to take up where stdio
leaves off. The product of a make in this directory is either:
4bsdlibc.a -- the version for 4.{23} BSD
s5libc.a -- the version for system V
3klibc.a -- the version for our Cray system V
v9libc.a -- the version for btl 9th edition Unix