If you just want to process the file periodically when it has changed, you can: 
my $old_time = (stat( $file ))[9];

while ( 1 ) {
    sleep $period_in_seconds;
    my $current_time = (stat($file))[9];
    while ( $current_time != $old_time ) {
         $old_time = $current_time;
          print "file changed$/";
          $current_time = (stat($file))[9];
    }
}

[download]
The above nods at the issue of race conditions; it ignores possible contention issues.

Be well,
rir

In reply to Re: Getting the timestamp of a file by rir
in thread Getting the timestamp of a file by becca23

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