Try: 
lock(*FH);

sub lock {
  my $fh = shift;
  flock($fh,LOCK_EX);
}

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The reason is, that FH is not known to lock, cause it's only visible inside your add() sub. 
-----------------------------------
--the good, the bad and the physi--
-----------------------------------

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In reply to Re: error stating flock requires more args by physi
in thread error stating flock requires more args by c

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