$ perl -MPOSIX -e'use strict; print POSIX::OREAD;'
$ perl -MPOSIX -e'use strict; print abs(POSIX::OREAD);'
Bareword "POSIX::OREAD" not allowed while "strict subs" in use at -e line 1.
Execution of -e aborted due to compilation errors.
$ perl -MPOSIX -e'use strict; print POSIX::OREAD();'
OREAD is not a valid POSIX macro at -e line 1