NAME

tpop3d - small, fast, extensible POP3 server

SYNOPSIS

tpop3d -h | [ -f file ] [ -p file ] [ -dvP ]

DESCRIPTION

tpop3d is a server which implements the RFC1939 POP3 protocol, including UIDL support. tpop3d supports virtual domain authentication via a number of mechanisms, POP-before-SMTP relaying, TCP wrappers, Maildir mailboxes and various other useful features. It is a daemon which waits in the background and accepts incoming connections. It cannot be operated from inetd(8).

tpop3d logs most diagnostics via syslog(3), using facility mail or another which is defined in its configuration file.

Detailed control over the operation of tpop3d is exercised by editing its configuration file, by default /usr/local/etc/tpop3d.conf. See the manual entry for tpop3d.conf(5) for more information.

OPTIONS

-h: Print a summary of usage and the compile-time options of this tpop3d.
-f file: Read configuration from file, instead of from /usr/local/etc/tpop3d.conf.
-p file: Write the PID of the server process to file. By default, no PID file is written.
-d: Do not fork to become a daemon, but stay attached to a controlling terminal and print log messages to standard error as well as the syslog
-v: Log traffic being sent to/from the server, for debugging purposes; tpop3d will log commands and responses sent, but not passwords or the actual content of messages.
-P: If tpop3d is compiled with TLS support, and is configured to use a key protected by a passphrase, tpop3d will wait to read the passphrase at startup. Do not use this option when starting tpop3d from a boot script; it might wait forever for input on the console.

SIGNALS

SIGTERM, SIGINT: Cause the daemon to exit, closing any active connections.
SIGHUP: Cause the daemon to restart, re-reading its configuration file. This will not close active connections which have already been authenticated.
other signals: Most other signals are ignored, though some (SIGSEGV etc.) will cause the daemon to terminate prematurely. In these circumstances, tpop3d should clear up all of its lock files. However, if this happens, it indicates either a bug in tpop3d, or a hardware problem. In the former case, please contact me (see below for contact details) with information about your configuration and (if known) steps which may be taken to reproduce the bug. In particular, the configuration options which you used to compile tpop3d and the operating system and version under which you are running it are essential information for a bug report.

BUGS

Locking of mailspools under Unix is problematic, mostly because of past brokenness which has now been fixed. tpop3d's locking scheme should suffice in most cases (and should work reliably over NFS) but it is naive: it locks the mailspool for exclusive access, so that an MTA cannot deliver mail to the mailspool whilst it is being accessed by a tpop3d user. As a result, it is configured by default to time out users rather rapidly (after 30s of inactivity). This is one of several places where it is marginally noncompliant with RFC1939. Note that the locking issues do not apply to maildir mailboxes.

Authentication drivers block the main daemon; this means that a failure in NIS or an external program could prevent tpop3d from handling new connections. A future version may support asynchronous authentication drivers.

If TCP Wrappers support is enabled, then reverse-DNS resolution of connected client addresses may also block the main daemon.

FILES

/usr/local/etc/tpop3d.conf

AUTHOR

Chris Lightfoot <chris@ex-parrot.com>. Portions by Mark Longair and Paul Makepeace.

If you have a query about tpop3d, please do not send me personal email. Instead, please send it to the tpop3d mailing list, to which you can subscribe by sending an email with the subject `subscribe' to
<tpop3d-discuss-request@lists.beasts.org>. There is a mailing list archive at
http://lists.beasts.org/pipermail/tpop3d-discuss/.

VERSION

$Id$

COPYING

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.