Have you tried using alarm()?

# untested with your particular situation, but should be a guide.
 eval {
        local $SIG{ALRM} = sub { die "lock\n" }; # NB: \n required
        alarm 5;
        flock(LOCK, LOCK_EX | LOCK_NB);
        alarm 0;
    };
    if ($@) {
        die unless $@ eq "lock\n";   
    } else {
        # keep going
    }

[download]

Cheers,
KM

In reply to Re: Non-Blocking Semaphore by KM
in thread Non-Blocking Semaphore by JackHammer

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