4.4BSD/usr/src/contrib/perl-4.036/eg/shmkill

#!/usr/bin/perl

# $Header: shmkill,v 4.0 91/03/20 01:14:20 lwall Locked $

# A script to call from crontab periodically when people are leaving shared
# memory sitting around unattached.

open(ipcs,'ipcs -m -o|') || die "Can't run ipcs: $!";

while (<ipcs>) {
    $tmp = index($_,'NATTCH');
    $pos = $tmp if $tmp >= 0;
    if (/^m/) {
	($m,$id,$key,$mode,$owner,$group,$attach) = split;
	if ($attach != substr($_,$pos,6)) {
	    die "Different ipcs format--can't parse!\n";
	}
	if ($attach == 0) {
	    push(@goners,'-m',$id);
	}
    }
}

exec 'ipcrm', @goners if $#goners >= 0;