POP3(8)                                                   POP3(8)

          pop3, imap4d - Internet mail servers

          upas/pop3 [ -d debugfile ][ -a mailbox ][ -r peeraddr ][ -t
          tlscertfile ][ -p ]

          upas/imap4d [-acpv] [-d smtpdomain] [-s servername]

          These programs support remote access to mail across the
          Internet.  All expect the network connection to be standard
          input, output, and error.  They are normally started from
          scripts in /rc/bin/service (see listen(8)).

          Pop3 provides access to a user's mailboxes via the POP3 pro-
          tocol.  The options are:

          -d  create debugfile and write debugging output to it

          -a  causes pop3 to assume that it already authenticated and
              to read mailbox immediately

          -r  causes pop3 to create the file
              /mail/ratify/trusted/peeraddr#32 to allow subsequent
              SMTP sessions from that address.  See ratfs(4) for

          -t  get the local TLS certificate from the file tlscertfile.

          -p  allow passwords in the clear for authenticating the con-

          Imap4d provides access to a user's mailboxes via the
          IMAP4rev1 protocol.  Only files rooted in
          /mail/box/username/ are accessible.  The list of subscribed
          mailboxes is contained in
          /mail/box/username/imap.subscribed, and initially contains
          only INBOX, IMAP's name for the user's mailbox.  A shadow
          file, mailbox.imp, is created for each mailbox examined.

          Imap4d's options are:

          a   Assume the user is already authenticated.  By default,
              the user must authenticate using CRAM-MD5 or
              securenet(8) challenge/response authentication.

          c   Allow plan 9 challenge response authentication.

          p   Allow login authentication.  This option should only be

     Page 1                       Plan 9             (printed 4/13/24)

     POP3(8)                                                   POP3(8)

              enabled for servers using an encrypted connection, such
              as SSL, and when enabled, all non-encrypted connections
              should be disallowed.  Imap4d does not enforce this pol-

          v   Turn on verbose output to the debug file.

          s   The server's name.  If none is provided, cs (see ndb(8))
              is queried or /env/sysname is used.

          d   The local mail domain.  Defaults to the server /env/site
              in the mail server's domain.

          For both imap4d and pop3, the password used to authenticate
          the connection is the APOP secret held by keyfs(4) running
          on the authentication server.

          /sys/log/imap4d                   debugging output


          aliasmail(8), faces(1), filter(1), mail(1), marshal(1),
          mlmgr(1), nedmail(1), qer(8), rewrite(6), send(8), upasfs(4)

          Usually messages flagged for deletion with DELE are not
          actually deleted until the client sends a QUIT command to
          end the conversation.  Pop3 implements a non-standard com-
          mand SYNC that deletes messages flagged for deletion without
          ending the conversation.

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