Recent discussions on IRC (I forget with whom, sorry), brought me back to thinking about syncing notmuch with imap. In addition to the flags \Seen, \Answered, \Draft, \Deleted, and \Flagged, imap servers can optionally support user defined keywords (i.e. tags). At least courier and dovecot do. These keywords are imap "atoms", which, without tracing though the BNF  completely look like they can can have (ascii) alphanumeric, and punctuation other than brackets, quotes and "%", "*".
So the mapping is relatively nice between notmuch tags and imap keywords. One idea I had was to extend some imap syncing program to sync to notmuch. mbsync (confusingly also named isync) is a C based one. It is indeed relatively easy to add a new backend; I made a new "notmuch" driver for mbsync in an hour or so that is actually just a maildir driver. I am a little discouraged by some of mbsync code (there are lots of places with a buffer hard-coded to size 16, with a comment to change that later when keyword support is added), but in principle, I think this could work. A more fundamental issue is that mbsync, like most similar programs uses an index file to keep track of the sync state, and it seems somehow wrong (or at least fragile) to keep a second database with essentially the same information in it. To write a custom sync program would require some imap code; this is somewhere between trivial and not; mbsync's imap driver is about 1900 lines of C. There is the uw c-client library; I remember some security issues but that was more than a decade ago. There are some newer libraries like tinymail and libetpan, but they seem to have a whole bunch of stuff not needed for notmuch. d : http://www.faqs.org/rfcs/rfc3501.html _______________________________________________ notmuch mailing list email@example.com http://notmuchmail.org/mailman/listinfo/notmuch