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courierpop3d(8)


NAME

   courierpop3d - The Courier POP3 server

SYNOPSIS

   /usr/sbin/couriertcpd {-nodnslookup} {-stderr=syslog} {110}
                         {/usr/lib/courier/courier/courierpop3login}
                         [modules...]
                         {/usr/lib/courier/courier/courierpop3d}
                         {./Maildir}

DESCRIPTION

   This is a simple POP3 server for Maildirs.

       Note
       The couriertcpd, courierpop3login, and courierpop3d modules may be
       installed elsewhere than indicated here.

   courierpop3login is usually started by couriertcpd. It already expects
   that a POP3 client is connected to standard input and output,
   presumably via a network socket.  courierpop3login reads the POP3
   userid and password, then runs the authentication modules. The
   remaining arguments are passed along as arguments to modules.

   modules is one or more authentication modules (see the authlib(7)[1]
   manual page).

   Each authentication modules runs the program specified by its first
   argument, allowing the authentication modules to be chained. The last
   program in the chain is courierpop3d , which provides the actual POP3
   service. In accordance with the authentication protocol, as described
   in authlib(7)[1]courierpop3d reads file descriptor 3 to see if the
   userid/password has been succesfully validated. If not, courierpop3d
   terminates.

   Otherwise, courierpop3d expects to be already running under the
   appropriate user and group id, with its current directory set to the
   account's home directory.

   The first order of business is to find the account's Maildir. If the
   environment variable MAILDIR is set, that's where we go. That should be
   the pathname to the account's Maildir. The environment variable MAILDIR
   may be set by the authentication module. If MAILDIR is not set,
   courierpop3d uses its first argument. Usually, the default maildir is
   $HOME/Maildir, therefore the first argument to courierpop3d is
   "./Maildir".

SEE ALSO

   authlib(7)[1], userdb(8)[2].

AUTHOR

   Sam Varshavchik
       Author

NOTES

    1. authlib(7)
       [set $man.base.url.for.relative.links]/authlib.html

    2. userdb(8)
       [set $man.base.url.for.relative.links]/userdb.html



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