HOWTO get balsa managing existing MH folders Author: Stephan C . Buchert <scb@stelab.nagoya-u.ac.jp> Many users of balsa have an archive of their previously received, drafted, sent, deleted ... mails. Of course they want to manage these with balsa. Depending on the mail system that has been used the already existing messages are stored in different ways: 1) in the local computer as so-called mbox files 2) in the local computer as so-called MH folders 3) in a server as so-called IMAP folders This list is perhaps not complete. Here I describe how I got balsa managing my emails that are stored in MH folders, nr 2 above. The MH (Message Handling) system stores each e-mail message in a separate file. A directory with one or several files containing MH emails is an MH folder. Thus a part of the UNIX file system itself represents the structure of an MH mail archive. The root of this structure is typically at "/home/user/Mail", where "user" stands for the login name. In contrast to this, mbox files (nr 1 above) contain typically more than one message. An mbox file with only one message is not an MH message, and vice versa. MH mail data can be managed using the "low level" nmh tools, which are included in most Linux distributions, by exmh, which provides a GUI to the nmh tools, by two different packages for Emacs, namely mh-mail and Mew, and by others. Also Balsa can be used to manage your MH folders, as well as mbox files and IMAP folders. The latter two are mailboxes in balsa, but an error results if a balsa mailbox path is configured to an MH mail folder. Rather, my "Local Mail" in the window for "Mail Servers" from "Preferences" says "/home/scb/Mail" and balsa shows nicely all my MH folders which are under "/home/scb/Mail". There was another minor hurdle, before balsa really displayed my MH mails: Obviously balsa identifies MH mail folders by the existence of a file ".mh_sequences" in these folders. If, for example, the Emacs mh-mail package has been used before balsa, then there is no problem. However, I use a system called MEW (http://www.mew.org) which lets me see mail with Japanese characters using Emacs/Mule. Mew doesn't create files ".mh_sequences" (but rather files ".mew-cache"). Therefore I had to create (touch) files ".mh_sequences" in each MH folder. Concerning balsa these files ".mh_sequences" can be empty, they only must exist. Once balsa recognizes the MH folders as described above, it can handle both MH folders and mailboxes, transfer messages between these two etc.
