I have added a loop so that your comparison of one field against the row becomes a comparison of all fields against the row. That is what you wanted, no?

Have a look at each statement in that block one by one. If you don't understand anything there, try to find it in the documentation with perldoc. If you still don't understanding it you can say so here, specifying where you looked and how the documentation you read did not make it clear. You may also peruse the Tutorials here for further guidance.

Happy learning!

ok ignore the file3 it was basically for just saving the result to a new file. where can i get the syntax for passing arrays as a command line argument?

In Re^3: Comparision Utility PERL I recommended looking in the Tutorials section. If you had done that you might have found Parsing your script's command line which explains all.

i need to run this file as perl filename.pl file1 file2 file3 Col2 col3
i am very new to this . Also i reduced the sample.
i am not quite able to grasp what you meant because i need to use command line arguments

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.