arch.c: Don't require ranlib stuff. Not everybody has it.
dir.c: SunOS-4 != Solaris; change #ifdef sun to #if sun && !__svr4__
job.c, compat.c: Don't use 'union wait', use int and the W*() macros.
main.c: Check for uname() == -1; some unames return > 0...
util.c, job.c: Add signal() with BSD semantics for svr4, don't use bsd
sigmask and friends.