For small files read the file a line at a time and add the lines to a hash.

When you have read a line first check that it's not in the hash already. If not, print it to the output file and insert it into the hash, otherwise skip to the next line.

If you can't figure that out, write some code that is your best guess at how to do it, ask again and include your code.

DWIM is Perl's answer to Gödel

In reply to Re: Checking LInes in Text File by GrandFather
in thread Checking LInes in Text File by Anonymous Monk

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