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the Topic itself asks the Question. What does

cat emailsource | formail -I "From "

exactly? Does it simply remove all duplicate Froms? The Manpage is a little bit unclear to me.

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up vote 1 down vote accepted

Removes all the "From " headers from the message.

The "From " line is the delimiter for a unix mailbox. Notice, it doesn't contain a ":" like the "From:" header

Essentially UNIX mbox format keeps all your mails in one file. This is the polar opposite to something like Maildir which treats every mail as a separate file. Because multiple mails are in one file, they needed a delimiter and chose "From " at the top of the message

This would normally be done to convert a UNIX mbox mail so that it can be used elsewhere by a client or format that doesn't support it.


formail -s < /var/mail/phil | formail -I "From " # ...
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thank you, very informative answer. I need this to be explained in my bachelor work. Can you give me a reference, where I can Quote from? – evildead Nov 20 '09 at 2:04

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