By default, the aliases file contains the required aliases for the sendmail program. Do not delete these defaults because they are needed by the system. This file describes user ID aliases used by the sendmail command. It is formatted as a series of lines in the form: name: name_1, name_2, name_3,..
The name is the name that needs an alias, and the name_n are the aliases for that name. Lines beginning with white space are continuation lines. Lines beginning with a # (number sign) are comments.
You can define an alias only on local names. Duplicate addresses are removed and no message is sent to any person more than once. For example, if name_1 defines an alias that is name_2 and name_2 defines an alias that is name_1, sendmail does not send the same message back and forth. Local and valid recipients who have a .forward file in their home directory have messages forwarded to the list of users defined in that file.
This is only the raw data file; the actual information that defines the aliases is placed into a binary format in the files /var/adm/sendmail/aliases.dir and /var/adm/sendmail/aliases.pag using the newaliases command. For the change to take effect, the newaliases command must be executed each time the aliases file is changed.
The sendmail program also supports sending messages to programs or appending a message to a file. See the sendmail(8) reference page for further information.
Aliases for sendmail use the dbm(3) database format for faster lookups. A single alias cannot exceed 1,000 characters. To work around this restriction, you can chain together aliases. For example: alias-list: ali1, ali2, ali3 ali1: name 1, name 2 ... ali2: name n, name n + 1
Commands: newaliases(1), forward(4), local.users(4), sendmail(8) delim off