53497 Extract e-mails from text file

Apologies for any confusion as this is a re-post of a earlier project. Thunderbird integration and GUI are no longer necessary. Many thanks in advance for re-bidding on reduced scope... Develop a very simple command-line application to extract e-mail addresses from a text file and add to another text file only if not already present in the target text file and only if domain is not already present in a [login to view URL] text file.