======= ex ==========
hello: warnx test1: Cannot allocate memory
hello: errx test1: Cannot allocate memory
$?=21
hello: warnx test2, six=6: Cannot allocate memory
hello: errx test2, six=6: Cannot allocate memory
$?=22
errx(3): invalid argv
$?=94
hello: warn test1
hello: err test1
$?=11
hello: warn test2, five=5
hello: err test2, five=5
$?=12
err(3): invalid argv
$?=93
======= CLEANFILES ==========
hello.o
progname.o
err.o
warn.o
======= cleandir ==========