NAME

       mpopd - A minimal POP3 server

SYNOPSIS

       mpopd [option...]

DESCRIPTION

       Mpopd is a minimal POP3 server that delivers mails from a local mailbox in maildir format.
       It can be used by end users as a way to handle incoming mail via mpop  with  mail  clients
       that insist on using POP3. See the EXAMPLES section below.
       Mpopd  listens on 127.0.0.1 port 1100 by default, but can also run without its own network
       sockets in inetd mode, where it handles a single POP3 session on standard input / output.
       To prevent abuse, mpopd will allow only a limited number of concurrent POP3 sessions,  and
       an authentication failure occurrs, future authentication requests in any POP3 session will
       (for a limited duration) only be answered after a small delay.

OPTIONS

       --version
              Print version information

       --help Print help

       --inetd
              Start single POP3 session on stdin/stdout

       --interface=ip
              Listen on the given IPv6 or IPv4 address instead of 127.0.0.1

       --port=number
              Listen on the given port number instead of 25

       --log=none|syslog|filename
              Set logging: none (default), syslog, or logging to the given file.

       --auth=user[,passwordeval]
              Require authentication with this user name. The password will be retrieved from the
              given  passwordeval command (this works just like passwordeval in mpop) or, if none
              is given, from the key ring or, if that fails, from a prompt.

       --maildir=dir
              Use this maildir as the mailbox.

EXAMPLES

       Using mpopd to handle incoming mail for a POP3-based mail client
       Some mail clients cannot get incoming mail from local files and instead insist on using  a
       POP3  server.  You can configure mpopd to be that POP3 server and serve your incoming mail
       from a local maildir folder.
       (Similarly, some mail clients cannot send outgoing mail via a program such  as  msmtp  and
       instead  insist  on using an SMTP server.  You can configure msmtpd to be that SMTP server
       and hand the mail over to msmtp. See the relevant section in the msmtp manual.)
       For this purpose, mpopd should listen on an unprivileged port, e.g. 1100 (the default).  A
       mailbox  is defined using first the --auth option to set a user name and password and then
       using the --maildir option to specify the maildir folder that  holds  the  incoming  mail.
       Multiple  such  option pairs can be used to define multiple mailboxes, e.g. from different
       remote mail accounts.  Programs such as mpop can deliver new mail into the maildir folders
       at  any  time, but as long as mpopd is running no other programs may alter or remove mails
       from these folders.
       Let's use the user name mpopd-user. You have two options to manage the password:

              Store the password in your key ring, e.g. with secret-tool store --label=mpopd host
              localhost  service  pop3  user  mpopd-user.   In  this  case,  use the mpopd option
              --auth=mpopd-user.

              Store the password in an encrypted file and use the passwordeval mechanism. Example
              for gpg: mpopd ... --auth=mpopd-user,'gpg -q -d ~/.mpopd-password.gpg'

       The   complete   command   then   is   (using   the   keyring):   mpopd  --auth=mpopd-user
       --maildir=/path/to/your/maildir/folder
       The mail client software must then be  configured  to  use  localhost  at  port  1100  for
       incoming  mail  via  POP3, and to use authentication with user mpopd-user and the password
       you chose. The mail client will probably complain that the POP3 server  does  not  support
       TLS,  but in this special case that is ok since all communication between your mail client
       and mpopd will stay on the local machine.

SEE ALSO

       mpop(1)

                                             2021-09                                     MPOPD(1)