file for smtpd
This manual page describes the format of the
file, as used by
. An alias in its
simplest form is used to assign an arbitrary name to an email address, or a
group of email addresses. This provides a convenient way to send mail. For
example an alias could refer to all users of a group: email to that alias
would be sent to all members of the group. Much more complex aliases can be
defined however: an alias can refer to other aliases, be used to send mail to
a file instead of another person, or to execute various commands.
Within the file, ‘
’ is a comment delimiter;
anything placed after it is discarded. The file consists of key/value mappings
of the form:
key: value1, value2, value3,
is always folded to lowercase before alias
lookups to ensure that there can be no ambiguity. The key is expanded to the
corresponding values, which consist of one or more of the following:
- A user on the host machine. The user must have a valid
entry in the passwd(5)
- Append messages to file,
specified by its absolute pathname.
- Pipe the message to
command on its standard input. The
command is run under the privileges of the daemon's unprivileged
- Include any definitions in
file as alias entries. The format of the
file is identical to this one.
- An email address in RFC 5322 format. If an address
extension is appended to the user-part, it is first compared for an exact
match. It is then stripped so that an address such as email@example.com
will only use the part that precedes ‘+’ as a
- A status code and message to return. The code must be 3
digits, starting 4XX (TempFail) or 5XX (PermFail). The message must be
present and can be freely chosen.
- Deliver messages to Maildir at the
- Default aliases file.
file format appeared in