Re: [little OT] message-id

[Lars Hecking]

> Background: I'd like to write a perl script whose input is a
> mail folder, and the script looks at each individual email's
> message-id and do something with it (if it sees a duplicate,
> then ignore the duplicate, etc). If it doesn't find one,
> what should be done?

 No need for the perl monster. procmail+formail can do it nicely,
 and examples for what you want to do are more than likely in the
 procmailex(5) man page.