pop3d(3tcl) Tcl POP3 Server Package pop3d(3tcl)
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NAME
pop3d - Tcl POP3 server implementation
SYNOPSIS
package require Tcl 8.3
package require pop3d ?1.1.0?
::pop3d::new ?serverName?
serverName option ?arg arg ...?
serverName up
serverName down
serverName destroy ?mode?
serverName configure
serverName configure -option
serverName configure -option value...
serverName cget -option
serverName conn list
serverName conn state id
authCmd exists name
authCmd lookup name
storageCmd dele mbox msgList
storageCmd lock mbox
storageCmd unlock mbox
storageCmd size mbox ?msgId?
storageCmd stat mbox
storageCmd get mbox msgId
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DESCRIPTION
::pop3d::new ?serverName?
This command creates a new server object with an associated
global Tcl command whose name is serverName.
The command serverName may be used to invoke various operations on the
server. It has the following general form:
serverName option ?arg arg ...?
Option and the args determine the exact behavior of the command.
A pop3 server can be started on any port the caller has permission for
from the operating system. The default port will be 110, which is the
port defined by the standard specified in RFC 1939 (http://www.rfc-edi-
tor.org/rfc/rfc1939.txt). After creating, configuring and starting a
the server object will listen for and accept connections on that port
and handle them according to the POP3 protocol.
Note: The server provided by this module will handle only the basic
protocol by itself. For the higher levels of user authentication and
handling of the actual mailbox contents callbacks will be invoked.
The following commands are possible for server objects:
serverName up
After this call the server will listen for connections on its
configured port.
serverName down
After this call the server will stop listening for connections.
This does not affect existing connections.
serverName destroy ?mode?
Destroys the server object. Currently open connections are han-
dled depending on the chosen mode. The provided modes are:
kill Destroys the server immediately, and forcefully closes
all currently open connections. This is the default mode.
defer Stops the server from accepting new connections and will
actually destroy it only after the last of the currently
open connections for the server is closed.
serverName configure
Returns a list containing all options and their current values
in a format suitable for use by the command array set. The op-
tions themselves are described in section Options.
serverName configure -option
Returns the current value of the specified option. This is an
alias for the method cget. The options themselves are described
in section Options.
serverName configure -option value...
Sets the specified option to the provided value. The options
themselves are described in section Options.
serverName cget -option
Returns the current value of the specified option. The options
themselves are described in section Options.
serverName conn list
Returns a list containing the ids of all connections currently
open.
serverName conn state id
Returns a list suitable for [array set] containing the state of
the connection referenced by id.
OPTIONS
The following options are available to pop3 server objects.
-port port
Defines the port to listen on for new connections. Default is
110. This option is a bit special. If port is set to "0" the
server, or rather the operating system, will select a free port
on its own. When querying -port the id of this chosen port will
be returned. Changing the port while the server is up will nei-
ther change the returned value, nor will it change on which port
the server is listening on. Only after resetting the server via
a call to down followed by a call to up will the new port take
effect. It is at that time that the value returned when querying
-port will change too.
-auth command
Defines a command prefix to call whenever the authentication of
a user is required. If no such command is specified the server
will reject all users. The interface which has to be provided by
the command prefix is described in section Authentication.
-storage command
Defines a command prefix to call whenever the handling of mail-
box contents is required. If no such command is specified the
server will claim that all mailboxes are empty. The interface
which has to be provided by the command prefix is described in
section Mailboxes.
-socket command
Defines a command prefix to call for opening the listening
socket. This can be used to make the pop3 server listen on a
SSL socket as provided by the tls package, see the command
tls::socket.
AUTHENTICATION
Here we describe the interface which has to be provided by the authen-
tication callback so that pop3 servers following the interface of this
module are able to use it.
authCmd exists name
This method is given a username and has to return a boolean
value telling whether or not the specified user exists.
authCmd lookup name
This method is given a username and has to return a two-element
list containing the password for this user and a storage refer-
ence, in this order.
The storage reference is passed unchanged to the storage call-
back, see sections Options and Mailboxes for either the option
defining it and or the interface to provide, respectively.
MAILBOXES
Here we describe the interface which has to be provided by the storage
callback so that pop3 servers following the interface of this module
are able to use it. The mbox argument is the storage reference as re-
turned by the lookup method of the authentication command, see section
Authentication.
storageCmd dele mbox msgList
Deletes the messages whose numeric ids are contained in the ms-
gList from the mailbox specified via mbox.
storageCmd lock mbox
This method locks the specified mailbox for use by a single con-
nection to the server. This is necessary to prevent havoc if
several connections to the same mailbox are open. The complemen-
tary method is unlock. The command will return true if the lock
could be set successfully or false if not.
storageCmd unlock mbox
This is the complementary method to lock, it revokes the lock on
the specified mailbox.
storageCmd size mbox ?msgId?
Determines the size of the message specified through its id in
msgId, in bytes, and returns this number. The command will re-
turn the size of the whole maildrop if no message id was speci-
fied.
storageCmd stat mbox
Determines the number of messages in the specified mailbox and
returns this number.
storageCmd get mbox msgId
Returns a handle for the specified message. This handle is a
mime token following the interface described in the documenta-
tion of package mime. The pop3 server will use the functionality
of the mime token to send the mail to the requestor at the other
end of a pop3 connection.
SECURE MAIL TRANSFER
The option -socket (see Options) enables users of the package to over-
ride how the server opens its listening socket. The envisioned main
use is the specification of the tls::socket command, see package tls,
to secure the communication.
package require tls
tls::init \
...
pop3d::new S -socket tls::socket
...
REFERENCES
[1] RFC 1939 [http://www.rfc-editor.org/rfc/rfc1939.txt]
[2] RFC 2449 [http://www.rfc-editor.org/rfc/rfc2449.txt]
BUGS, IDEAS, FEEDBACK
This document, and the package it describes, will undoubtedly contain
bugs and other problems. Please report such in the category pop3d of
the Tcllib Trackers [http://core.tcl.tk/tcllib/reportlist]. Please
also report any ideas for enhancements you may have for either package
and/or documentation.
When proposing code changes, please provide unified diffs, i.e the out-
put of diff -u.
Note further that attachments are strongly preferred over inlined
patches. Attachments can be made by going to the Edit form of the
ticket immediately after its creation, and then using the left-most
button in the secondary navigation bar.
KEYWORDS
internet, network, pop3, protocol, rfc 1939, secure, ssl, tls
CATEGORY
Networking
COPYRIGHT
Copyright (c) 2002-2009 Andreas Kupries <andreas_kupries@users.sourceforge.net>
Copyright (c) 2005 Reinhard Max <max@suse.de>
tcllib 1.1.0 pop3d(3tcl)