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:

            eric@monet.berkeley.edu
            Eric Allman <eric@monet.berkeley.edu>
            eric@monet.berkeley.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%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  ("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" <eric@monet.berkeley.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 3.54 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)