~mdw / qmail / blame
| Commit | Line | Data |
|---|---|---|
| 212b6f5d MW |
1 | This file points out some reasons that you might want to switch from |
| 2 | mbox format to a new format, maildir. | |
| 3 | ||
| 4 | ||
| 5 | 1. The trouble with mbox | |
| 6 | ||
| 7 | The mbox format---the format of ~user/Mailbox, understood by BSD Mail | |
| 8 | and lots of other MUAs---is inherently unreliable. | |
| 9 | ||
| 10 | Think about it: what happens if the system crashes while a program is | |
| 11 | appending a new message to ~user/Mailbox? The message will be truncated. | |
| 12 | Even worse, if it was truncated in the middle of a line, it will end up | |
| 13 | being merged with the next message! Sure, the mailer understands that it | |
| 14 | wasn't successful, so it'll try delivering the message again later, but | |
| 15 | it can't fix your corrupted mbox. | |
| 16 | ||
| 17 | Other formats, such as mh folders, are just as unreliable. | |
| 18 | ||
| 19 | qmail supports maildir, a crashproof format for incoming mail messages. | |
| 20 | maildir is fast and easy for MUAs to use. Even better, maildir works | |
| 21 | wonders over NFS---see below. | |
| 22 | ||
| 23 | I don't want to cram maildir down people's throats, so it's not the | |
| 24 | default. Nevertheless, I encourage you to start asking for maildir | |
| 25 | versions of your favorite MUAs, and to switch over to maildir as soon as | |
| 26 | you can. | |
| 27 | ||
| 28 | ||
| 29 | 2. Sun's Network F_\bail_\bu_\bre System | |
| 30 | ||
| 31 | Anyone who tells you that mail can be safely delivered in mbox format | |
| 32 | over NFS is pulling your leg---as explained above, mbox format is | |
| 33 | inherently unreliable even on a single machine. | |
| 34 | ||
| 35 | Anyway, NFS is the most unreliable computing environment ever invented, | |
| 36 | and qmail doesn't even pretend to support mbox over NFS. | |
| 37 | ||
| 38 | You should switch to maildir, which works fine over NFS without any | |
| 39 | locking. You can safely read your mail over NFS if it's in maildir | |
| 40 | format. Any number of machines can deliver mail to you at the same time. | |
| 41 | (On the other hand, for efficiency, it's better to get NFS out of the | |
| 42 | picture---your mail should be delivered on the server that contains your | |
| 43 | home directory.) | |
| 44 | ||
| 45 | Here's how to set up qmail to use maildir for your incoming mail: | |
| 46 | ||
| 47 | % maildirmake $HOME/Maildir | |
| 48 | % echo ./Maildir/ > ~/.qmail | |
| 49 | ||
| 50 | Make sure you include the trailing slash on Maildir/. | |
| 51 | ||
| 52 | The system administrator can set up Maildir as the default for everybody | |
| 53 | by creating a maildir in the new-user template directory and replacing | |
| 54 | ./Mailbox with ./Maildir/ in /var/qmail/rc. | |
| 55 | ||
| 56 | Until your MUA supports maildir, you'll probably want to convert maildir | |
| 57 | format to (gaaack) mbox format. I've supplied a maildir2mbox utility | |
| 58 | that does the trick, along with some tiny qail and elq and pinq wrappers | |
| 59 | that call maildir2mbox before calling Mail or elm or pine. |