dot-qmail(5) Headers, Tables, and Macros dot-qmail(5) NAME dot-qmail - control the delivery of mail messages DESCRIPTION Normally the qmail-alias program delivers each incoming mes- sage to your system mailbox, homedir/Mailbox, where homedir is your home directory. It can instead write the mail to a different file or direc- tory, forward it to another address, distribute it to a mailing list, or even execute programs, all under your con- trol. THE QMAIL FILE To change qmail-alias's behavior, set up a .qmail file in your home directory. .qmail contains one or more lines. Each line is a delivery instruction. qmail-alias follows each instruction in turn. There are five types of delivery instructions: (1) comment; (2) program; (3) forward; (4) mbox; (5) maildir. (1) A comment line begins with a number sign: # this is a comment qmail-alias ignores the line. (2) A program line begins with a vertical bar: |/usr/ucb/vacation djb qmail-alias takes the rest of the line as a command to supply to sh. See qmail-command(8) for further infor- mation. (3) A forward line begins with an ampersand: &me@new.job.com qmail-alias takes the rest of the line as a mail address; it uses qmail-queue to forward the message to that address. The address must contain a fully quali- fied domain name; it must not contain extra spaces, angle brackets, or comments: # the following examples are WRONG &me@new &<me@new.job.com> & me@new.job.com &me@new.job.com (New Address) SunOS 5.5 Last change: 1 dot-qmail(5) Headers, Tables, and Macros dot-qmail(5) If the address begins with a letter or number, you may leave out the ampersand: me@new.job.com Note that qmail-alias omits its new Return-Path line when forwarding messages. (4) An mbox line begins with a slash or dot, and does not end with a slash: /home/djb/Mailbox.sos qmail-alias takes the entire line as a filename. It appends the mail message to that file, using flock- style file locking if possible. qmail-alias stores the mail message in mbox format, as described in mbox(5). WARNING: On many systems, anyone who can read a file can flock it, and thus hold up qmail-alias's delivery forever. Do not deliver mail to a publicly accessible file! If qmail-alias is able to lock the file, but has trou- ble writing to it (because, for example, the disk is full), it will truncate the file back to its original length. However, it cannot prevent mailbox corruption if the system crashes during delivery. (5) A maildir line begins with a slash or dot, and ends with a slash: /home/djb/Maildir/ qmail-alias takes the entire line as the name of a directory in maildir format. It reliably stores the incoming message in that directory. See maildir(5) for more details. If .qmail has the execute bit set, it must not contain any program lines, mbox lines, or maildir lines. If qmail-alias sees any such lines, it will stop and indicate a temporary failure. If .qmail is completely empty (0 bytes long), or does not exist, qmail-alias appends the mail message to your system mailbox in mbox format. .qmail may contain extra spaces and tabs at the end of a line. Blank lines are allowed, but not for the first line of .qmail. SunOS 5.5 Last change: 2 dot-qmail(5) Headers, Tables, and Macros dot-qmail(5) If .qmail is world-writable or group-writable, qmail-alias stops and indicates a temporary failure. SAFE QMAIL EDITING Incoming messages can arrive at any moment. If you want to safely edit your .qmail file, first set the sticky bit on your home directory: chmod +t $HOME qmail-alias will temporarily defer delivery of any message to you if your home directory is sticky (or group-writable or other-writable, which should never happen). Make sure to chmod -t $HOME when you are done! It's a good idea to test your new .qmail file as follows: qmail-alias -n $USER $HOME $USER '' '' '' '' EXTENSION ADDRESSES In the qmail system, you control all local addresses of the form user-anything, as well as the address user itself, where user is your account name. Delivery to user-anything is controlled by the file homedir/.qmail-anything. (These rules may be changed by the system administrator; see qmail- users(5).) The alias user controls all other addresses. Delivery to local is controlled by the file homedir/.qmail-local, where homedir is alias's home directory. In the following description, qmail-alias is handling a mes- sage addressed to local@domain, where local is controlled by .qmail-ext. Here is what it does. If .qmail-ext is completely empty, qmail-alias appends the mail message to your system mailbox. If .qmail-ext doesn't exist, qmail-alias will try some default .qmail files. For example, if ext is foo-bar, qmail-alias will try first .qmail-foo-bar, then .qmail-foo- default, and finally .qmail-default. If none of these exist, qmail-alias will bounce the message. (Exception: for the basic user address, qmail-alias treats a nonexistent .qmail the same as an empty .qmail.) WARNING: For security, qmail-alias replaces any dots in ext with colons before checking .qmail-ext. For convenience, qmail-alias converts any uppercase letters in ext to lower- case. SunOS 5.5 Last change: 3 dot-qmail(5) Headers, Tables, and Macros dot-qmail(5) When qmail-alias forwards a message as instructed in .qmail-ext (or .qmail-default), it checks whether .qmail-ext-owner exists. If so, it uses local-owner@domain as the envelope sender for the forwarded message. Otherwise it retains the envelope sender of the original message. Exception: qmail-alias always retains the original envelope sender if it is the empty address or #@[], i.e., if this is a bounce message. qmail-alias also supports variable envelope return paths (VERPs): if .qmail-ext-owner and .qmail-ext-owner-default both exist, it uses local-owner-@domain-@[] as the envelope sender. This will cause a recipient recip@reciphost to see an envelope sender of local-owner-recip=reciphost@domain. ERROR HANDLING If a delivery instruction fails, qmail-alias stops immedi- ately and reports failure. qmail-alias handles forwarding after all other instructions, so any error in another type of delivery will prevent all forwarding. If a program returns exit code 99, qmail-alias ignores all succeeding lines in .qmail, but it still pays attention to previous forward lines. To set up independent instructions, where a temporary or permanent failure in one instruction does not affect the others, move each instruction into a separate .qmail-ext file, and set up a central .qmail file that forwards to all of the .qmail-exts. Note that qmail-alias can handle any number of forward lines simultaneously. SEE ALSO envelopes(5), maildir(5), mbox(5), qmail-users(5), qmail- alias(8), qmail-command(8), qmail-queue(8), qmail-lspawn(8) SunOS 5.5 Last change: 4