Pop3d is a mailbox server based on the Internet Standard
STD 53, Post Office Protocol Version 3. The
server requires user and password verification before a
maildrop can be opened. The server can retrieve and delete
messages from the maildrop on a per-message basis.
Pop3d currently supports the following POP3 commands; the
commands are case independent.

Command			  Description
USER			specify user for maildrop access
PASS			specify password for maildrop access
APOP			specify user and hashed password for maildrop access
STAT			give message count and size of maildrop
LIST			list size of individual messages
RETR			retrieve a message
DELE			delete a message
NOOP			do nothing, return a positive response
LAST			give highest message number accessed
RSET			unmark messages marked for deletion
TOP			retrieve part of a message
UIDL			retrieve the unique ID for a message
QUIT			terminate session
The remaining optional commands specified in STD 53 (RPOP) is 
not implemented.

The server runs in "inetd" mode by default or with the -i option
and it expects to be started by some server process such as inetd.
If the -b option is given, it is run as a standalone server in the
background (and should NOT be listed in inetd.lst or inetd.conf).  
Pop3d listens for TCP requests on port 110 or on "portno" if the
-p portno option is given.
The -h option prints usage and command line options.

----------------

Installation.

You must decide to run pop3d from inetd or standalone.

FOR INETD INSTALLATIONS:
- Add an entry for pop3d in the file %ETC%\inetd.lst
  (or %ETC%\inetd.cnf for ported version of inetd).
  It should look like this:

  pop3 tcp d:\tcpip\bin\pop3d.exe -d
  or   
  pop3 stream tcp nowait root d:\tcpip\bin\pop3d -d %s

FOR STANDALONE INSTALLATIONS:
- Be sure that inetd isn't listening for pop3 connections already.
- Then start the daemon running now by hand:
  d:\tcpip\bin\pop3d.exe -b
- Added the daemon to a startup script.
  Use the same command as given above:  d:\tcpip\bin\pop3d.exe -b

Note: in standalone installation pop3d spawns the separate child
process for each connection.

----------------

Command line options:

  -h       Help message.
  -d       Debug logging mode (to the %ETC%\pop3d.log file)
  -s       Enable logging to syslog.
  -i       Inetd mode (default).
  -b       Background daemon mode.
  -p port  Listening port number.

----------------

User/password/mailbox configuration.

Two methods are currently supported for USER/PASS verification.

1. If the MAILBOX environment variable is defined, the
name for mailbox directory for user USERNAME constructs
as %MAILBOX%\username. The encrypted passwords for users placed in
UNIX-like %ETC%\passwd file:

#User:Password
username:2c0RlCFZHDMEA
postmaster:465Kf4fXaTr9s
unknown:5a5SZFHFTF2mE

The name of this file may be redefined by setting the 
PASSWORDS environment variable, for example

SET PASSWORDS=d:\tcpip\pop3d\passwd

Use admin.exe utility to create/change this file.

2. All information contains in old-style %ETC%\mailaddr file:

#User           Directory       Password
username    d:\mail\username    secret
postmaster  d:\mail\postmaster  big_secret
unknown     d:\mail\bad_mail    very_bad

The passwords are not enrypted.


   For APOP verification the MAILBOX environment variable must be
defined and unencrypted passwords must be placed in %ETC%\apop.cnf:

#User:Password
username:secret
postmaster:big_secret
unknown:very_bad

----------------

Mail delivering.

mailrcv.exe is the mail delivering program for OS/2 sendmail.
It's necessary to edit local mailer section in the file 
%ETC%\sendmail.cf:

Mlocal, P=d:\tcpip\pop3d\mailrcv.exe, F=lsmDFP,  S=10, R=20, A=__path__ $u

where __path__ is the name of MAILBOX directory (when ended by '\'
character) or the full name of %ETC%\mailaddr file. Examples:

Mlocal, P=d:\tcpip\pop3d\mailrcv.exe, F=lsDFP,  S=10, R=20, A=d:\mail\ $u
or
Mlocal, P=d:\tcpip\pop3d\mailrcv.exe, F=lsDFP,  S=10, R=20, A=d:\mptn\etc\mailaddr $u

An editor that prevents TAB characters from expanding have to be used
(for example E).
"unknown" is the reserved user name for delivering all messages,
addressed to unknown users.

