If you want the user to specify specific column numbers then you can pass that as an array in the range of the for loop instead of using all the columns. eg:

my @cols = (0, 2); # You would actually get these from @ARGV but it do
+esn't matter here

# ...

    for my $fieldnum (@cols) {
        if ( exists $hash{ $fields[$fieldnum] } ) {
            print $fh "$row\n";
            next;
        }
    }

[download]

I'm going to ignore any mention of "file3" since this is the first time you have brought it up. See also How do I change/delete my post? lest your changes make no sense.

In reply to Re^5: Comparision Utility PERL by hippo
in thread Comparision Utility PERL by vighneshmufc

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