sub Sem_P {
        my $x;
        open(LOCK, ">$lockfile");

        #Attempt to get a lock
        for($x = 0; ($x = $Lock_Tries) && !flock(LOCK, LOCK_EX | LOCK_NB); $x++) {
                #Sleep using select for a granularity 
                #of less than 1 second
                select(undef, undef, undef, $Lock_Timeout);
        }

        return ($x =< $Lock_Tries);
}