The problem with this:

     print `sh /root/scripts/security.sh&`;
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is that perl will decide that there is probably (possibly) output to be returned by the sub-shell, and since the backticks are being used to "capture" the output for use by the script, it has to wait for the process to finish, even though the shell is being backgrounded.

The way around that is to run the script in such a way that perl will not decide that it needs to wait for the process to finish so it can capture the output. Either of the following two alternatives would do:

• redirect output within the command string -- perl will figure this out, and realize that there won't be any output to capture:

      `sh /some/job.sh >/dev/null &`;
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• use "system()" instead of backticks -- perl isn't supposed to even try capturing output from system calls, just the exit status:

      $exit_status = system( "/some/job.sh &" );
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