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:

            ericATmonet.edu
            Eric Allman <ericATmonet.edu>
            ericATmonet.edu (Eric Allman)

       The domain part ("monet.berkeley.edu") 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  ("eric")  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%SOMETHINGATsome.where
            machine!machine!nameATsome.where
            I2461572ATsome.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 ("Eric Allman") 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 ".":

            "Eric P. Allman" <ericATmonet.edu>

   Abbreviation.
       Many mail systems let users abbreviate the  domain  name.   For  instance,  users  at  berkeley.edu  may  get  away  with
       "eric@monet" to send mail to Eric Allman.  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

SEE ALSO
       binmail(1), mail(1), mconnect(1), aliases(5), forward(5), sendmail(8), vrfy(8)

       RFC 2822 (Internet Message Format)

COLOPHON
       This page is part of release 3.25 of the Linux man-pages project.  A description of the project,  and  information  about
       reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.



4.2 Berkeley Distribution                                  2004-09-15                                                MAILADDR(7)