The name exec is poorly chosen for a perl sub. See perldoc -f exec.

The preferred way of passing an error value along is to do so directly:

#from 'exec' sub
    &log_action($error) if ($count > 0);
    # ...
#later...
sub log_action {
   my $error = shift;
   print "\n$error\n\n" &&
   # next print FH is fishy. When is FH opened and closed?
   print FH "$format $error" if $error;
}
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It is bad design to use globals or widely scoped lexicals to pass values to subs.

After Compline,
Zaxo