gnus: About mairix
8.2.1 About mairix
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Mairix is a tool for indexing and searching words in locally stored
mail. It was written by Richard Curnow and is licensed under the GPL.
Mairix comes with most popular GNU/Linux distributions, but it also runs
under Windows (with cygwin), macOS and Solaris. The homepage can be
found at <http://www.rpcurnow.force9.co.uk/mairix/index.html>
Though mairix might not be as flexible as other search tools like
swish++ or namazu, which you can use via the ‘nnir’ back end, it has the
prime advantage of being incredibly fast. On current systems, it can
easily search through headers and message bodies of thousands and
thousands of mails in well under a second. Building the database
necessary for searching might take a minute or two, but only has to be
done once fully. Afterwards, the updates are done incrementally and
therefore are really fast, too. Additionally, mairix is very easy to
set up.
For maximum speed though, mairix should be used with mails stored in
‘Maildir’ or ‘MH’ format (this includes the ‘nnml’ back end), although
it also works with mbox. Mairix presents the search results by
populating a _virtual_ maildir/MH folder with symlinks which point to
the “real” message files (if mbox is used, copies are made). Since
mairix already presents search results in such a virtual mail folder, it
is very well suited for using it as an external program for creating
_smart_ mail folders, which represent certain mail searches.