The semantics for nonblocking flock are to return false if the lock was not obtained, true if it was. If the platform does not support flock a fatal error is thrown.

You are apparantly on a win32ish system, which may or may not support flock, so it would be good to catch the error. See perlport and perlwin32 for details. Try something like this, 

use Fcntl ':flock' ;
open ONE, ">> C:\\temp\\RTEOlock.log" or die $!;
my $lck = eval {flock ONE, LOCK_EX | LOCK_NB};
die 'flock not supported! ', $@ if $@;
if ($lck) {
    # The other script is not running code here
}
else {
    # The other script is running code here
}

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For this semaphore system to be effective, the other script should flock the flag file first thing, and drop the lock at the very last, perhaps in a DESTROY() sub.

After Compline,
Zaxo

In reply to Re: use flock() to determine if other script is running by Zaxo
in thread use flock() to determine if other script is running by Red_Dragon

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