Plan 9 from Bell Labs’s /usr/web/sources/contrib/gabidiaz/root/sys/src/cmd/perl/t/op/subst_wamp.t
#!./perl $dummy = defined $&; # Now we have it... for $file ('op/subst.t', 't/op/subst.t', ':op:subst.t') { if (-r $file) { do ($^O eq 'MacOS' ? $file : "./$file"); exit; } } die "Cannot find op/subst.t or t/op/subst.t\n";