I applied the usual, build an array, sort, take out the unique addresses, write them to a new file.
For me, "the usual" would be: 
    $ sort -u file > file.$$ && mv file.$$ file

[download]

Would even work without much ram.

Abigail

In reply to Re: How to process two files of over a million lines for changes by Abigail-II
in thread How to process two files of over a million lines for changes by richard5mith

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