mboxgrep

Utility to scan mailboxes for messages matching a regular expression

mboxgrep is a small utility that scans a mailbox for messages matching a regular expression. Found messages can be either displayed on standard output, counted, deleted, piped to a shell command or written to another mailbox. Its features include: * ability to limit the search to message body or headers (although the whole message is scanned by default) * message counting * ability to invert the sense of matching * ability to write found messages to another mailbox * support for mbox (either plain or compressed), MH, nnmh, nnml and maildir folders * support for basic and extended POSIX regular expressions, and, optionally, Perl-complatible regular expressions (if linked with the PCRE library)