After looking at the Monks' flock tutorial and the man pages on the sytem, I tried the following: 
use Fcntl qw/:flock/;

OPEN(LOCKFILE, ">.lockfile") || die "another process already running";
flock LOCKFILE, LOCK_EX;

long_and_boring_function_call();
close LOCKFILE;  #close unlocks file

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Some tutorials say to die at the open statement. Others tutorials say to die at the flock statement. However the perldocs (perlfunc page) say that flock will spin until it gets a lock. Thus it will never fail (and never die).

I've tried to die at the open statement, and the flock statement; in both situations it does the "spin until it's free" behaviour.It waits for the first process to stop, then successfully obtains a lock.

So what am I doing wrong? How can one use flock to ensure that the process **dies**? (Or is there another way?)

Any enlightenment on this simple problem is most appreciated. :-)

April

edited: Sat Apr 5 21:46:42 2003 by jeffa - added code tags

In reply to Question about Flock and die by acarvalh

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