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MAILADDR(7) Linux User's Manual MAILADDR(7)

NAME

     mailaddr - mail addressing description

DESCRIPTION

     This  manual page gives a brief introduction to SMTP mail addresses, as
     used on the Internet.  These addresses are in the general format

          user@domain

     where a domain is a  hierarchical  dot-separated  list  of  subdomains.
     These examples are valid forms of the same address:

          john.doe@monet.example.com
          John Doe <john.doe@monet.example.com>
          john.doe@monet.example.com (John Doe)

     The  domain  part ("monet.example.com") is a mail-accepting domain.  It
     can be a host and in the past it usually was, but it  doesn't  have  to
     be.  The domain part is not case sensitive.

     The  local  part  ("john.doe")  is often a username, but its meaning is
     defined by  the  local  software.   Sometimes  it  is  case  sensitive,
     although  that  is  unusual.   If  you see a local-part that looks like
     garbage, it is usually because of a gateway between an internal  e-mail
     system and the net, here are some examples:

          "surname/admd=telemail/c=us/o=hp/prmd=hp"@some.where
          USER%SOMETHING@some.where
          machine!machine!name@some.where
          I2461572@some.where

     (These  are,  respectively, an X.400 gateway, a gateway to an arbitrary
     internal mail system  that  lacks  proper  internet  support,  an  UUCP
     gateway, and the last one is just boring username policy.)

     The  real-name  part ("John Doe") can either be placed before <>, or in
     () at the end.  (Strictly speaking the two aren't  the  same,  but  the
     difference  is beyond the scope of this page.)  The name may have to be
     quoted using "", for example, if it contains ".":

          "John Q. Doe" <john.doe@monet.example.com>

 Abbreviation
     Some mail systems let users abbreviate the domain name.  For  instance,
     users at example.com may get away with "john.doe@monet" to send mail to
     John Doe.  This behavior is deprecated.  Sometimes it  works,  but  you
     should not depend on it.

 Route-addrs
     In the past, sometimes one had to route a message through several hosts
     to get it to its final destination.  Addresses which show these  relays
     are termed "route-addrs".  These use the syntax:

          <@hosta,@hostb:user@hostc>

     This  specifies that the message should be sent to hosta, from there to
     hostb, and finally to hostc.  Many hosts disregard route-addrs and send
     directly to hostc.

     Route-addrs  are  very  unusual  now.  They occur sometimes in old mail
     archives.  It is generally possible to ignore all but the  "user@hostc"
     part of the address to determine the actual address.

 Postmaster
     Every  site  is  required  to  have  a  user  or  user alias designated
     "postmaster" to which problems with the mail system may  be  addressed.
     The "postmaster" address is not case sensitive.

FILES

     /etc/aliases
     ~/.forward