# mailaddr(7) - man - phpman

[MAILADDR(7)](https://www.chedong.com/phpMan.php/man/MAILADDR/7/markdown)                              Linux User's Manual                             [MAILADDR(7)](https://www.chedong.com/phpMan.php/man/MAILADDR/7/markdown)



## 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_

## SEE ALSO
       [**mail**(1)](https://www.chedong.com/phpMan.php/man/mail/1/markdown), [**aliases**(5)](https://www.chedong.com/phpMan.php/man/aliases/5/markdown), [**forward**(5)](https://www.chedong.com/phpMan.php/man/forward/5/markdown), [**sendmail**(8)](https://www.chedong.com/phpMan.php/man/sendmail/8/markdown)

       IETF RFC 5322 ⟨<http://www.ietf.org/rfc/rfc5322.txt>⟩

## COLOPHON
       This  page  is  part  of  release  5.10 of the Linux _man-pages_ project.  A description of the
       project, information about reporting bugs, and the latest version of this page, can be  found
       at <https://www.kernel.org/doc/man-pages/>.



4.2 Berkeley Distribution                    2020-08-13                                  [MAILADDR(7)](https://www.chedong.com/phpMan.php/man/MAILADDR/7/markdown)