This is a subroutine in package. 
sub trun {
    my $string = shift or return "";
    my $max = shift or return $string;
....
}

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From other .pl file arguments are passed. trun($string_file,$maximum); How the values are assigned to string_file and $maximum. Can you please tell me what is "shift or return """.

In reply to Shift or return by sandy1028

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