Instead of:

`curl -o /dev/null -m 222 \"$Link\" 2>> $logFile`
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Try:

open(STDERR, ">>", $logfile) or die "Failed to open $logfile: $!";
exec curl =>
  -o => "/dev/null",
  -m => 222,
  $Link;
die "Could not exec curl: $!";
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Now the run_on_finish() should capture the exit status of curl (or some other failure like opening the log file or not being able to run curl).