Net::POP3(3p) | Perl Programmers Reference Guide | Net::POP3(3p)

# NAME

Net::POP3 - Post Office Protocol 3 Client class (RFC1939)

# SYNOPSIS

        use Net::POP3;
        # Constructors
        $pop = Net::POP3->new('pop3host');
        $pop = Net::POP3->new('pop3host', Timeout => 60);
        $pop = Net::POP3->new('pop3host', SSL => 1, Timeout => 60);
        if ($pop->login($username, $password) > 0) {
          my $msgnums = $pop->list; # hashref of msgnum => size
          foreach my $msgnum (keys %$msgnums) {
            my $msg = $pop->get($msgnum);
            print @$msg;
            $pop->delete($msgnum);
          }
        }
        $pop->quit;

# DESCRIPTION

This module implements a client interface to the POP3 protocol, enabling a perl5 application to talk to POP3 servers. This documentation assumes that you are familiar with the POP3 protocol described in RFC1939. With IO::Socket::SSL installed it also provides support for implicit and explicit TLS encryption, i.e. POP3S or POP3+STARTTLS.

A new Net::POP3 object must be created with the new method. Once this has been done, all POP3 commands are accessed via method calls on the object.

The Net::POP3 class is a subclass of Net::Cmd and (depending on avaibility) of IO::Socket::IP, IO::Socket::INET6 or IO::Socket::INET.

## Class Methods

"new([$host][, %options])"
  This is the constructor for a new Net::POP3 object. $host is the name of the remote host to which an POP3 connection is required.

  $host is optional. If $host is not given then it may instead be passed as the "Host" option described below. If neither is given then the "POP3_Hosts" specified in "Net::Config" will be used.

  %options are passed in a hash like fashion, using key and value pairs. Possible options are:

  Host - POP3 host to connect to. It may be a single scalar, as defined for the "PeerAddr" option in IO::Socket::INET, or a reference to an array with hosts to try in turn. The "host" method will return the value which was used to connect to the host.

  Port - port to connect to. Default - 110 for plain POP3 and 995 for POP3s (direct SSL).

  SSL - If the connection should be done from start with SSL, contrary to later upgrade with "starttls". You can use SSL arguments as documented in IO::Socket::SSL, but it will usually use the right arguments already.

  LocalAddr and LocalPort - These parameters are passed directly to IO::Socket to allow binding the socket to a specific local address and port. For compatibility with older versions ResvPort can be used instead of LocalPort.

  Domain - This parameter is passed directly to IO::Socket and makes it possible to enforce IPv4 connections even if IO::Socket::IP is used as super class. Alternatively Family can be used.

  Timeout - Maximum time, in seconds, to wait for a response from the POP3 server (default: 120)

  Debug - Enable debugging information

## Object Methods

Unless otherwise stated all methods return either a true or false value, with true meaning that the operation was a success. When a method states that it returns a value, failure will be returned as undef or an empty list.

"Net::POP3" inherits from "Net::Cmd" so methods defined in "Net::Cmd" may be used to send commands to the remote POP3 server in addition to the methods documented here.

host()
  Returns the value used by the constructor, and passed to IO::Socket::INET, to connect to the host.
"auth($username, $password)"
  Attempt SASL authentication.
user($user)
  Send the USER command.
pass($pass)
  Send the PASS command. Returns the number of messages in the mailbox.
"login([$user[, $pass]])"
  Send both the USER and PASS commands. If $pass is not given the "Net::POP3" uses "Net::Netrc" to lookup the password using the host and username. If the username is not specified then the current user name will be used.

  Returns the number of messages in the mailbox. However if there are no messages on the server the string "0E0" will be returned. This is will give a true value in a boolean context, but zero in a numeric context.

  If there was an error authenticating the user then undef will be returned.

starttls(%sslargs)
  Upgrade existing plain connection to SSL. You can use SSL arguments as documented in IO::Socket::SSL, but it will usually use the right arguments already.
"apop([$user[, $pass]])"
  Authenticate with the server identifying as $user with password $pass. Similar to "login", but the password is not sent in clear text.

  To use this method you must have the Digest::MD5 or the MD5 module installed, otherwise this method will return undef.

banner()
  Return the sever's connection banner
capa()
  Return a reference to a hash of the capabilities of the server. APOP is added as a pseudo capability. Note that I've been unable to find a list of the standard capability values, and some appear to be multi-word and some are not. We make an attempt at intelligently parsing them, but it may not be correct.
capabilities()
  Just like capa, but only uses a cache from the last time we asked the server, so as to avoid asking more than once.
"top($msgnum[, $numlines])"
  Get the header and the first $numlines of the body for the message $msgnum. Returns a reference to an array which contains the lines of text read from the server.
list([$msgnum])
  If called with an argument the "list" returns the size of the message in octets.

  If called without arguments a reference to a hash is returned. The keys will be the $msgnum's of all undeleted messages and the values will be their size in octets.

"get($msgnum[, $fh])"
  Get the message $msgnum from the remote mailbox. If $fh is not given then get returns a reference to an array which contains the lines of text read from the server. If $fh is given then the lines returned from the server are printed to the filehandle $fh.
getfh($msgnum)
  As per get(), but returns a tied filehandle. Reading from this filehandle returns the requested message. The filehandle will return EOF at the end of the message and should not be reused.
last()
  Returns the highest $msgnum of all the messages accessed.
popstat()
  Returns a list of two elements. These are the number of undeleted elements and the size of the mbox in octets.
ping($user)
  Returns a list of two elements. These are the number of new messages and the total number of messages for $user.
uidl([$msgnum])
  Returns a unique identifier for $msgnum if given. If $msgnum is not given "uidl" returns a reference to a hash where the keys are the message numbers and the values are the unique identifiers.
delete($msgnum)
  Mark message $msgnum to be deleted from the remote mailbox. All messages that are marked to be deleted will be removed from the remote mailbox when the server connection closed.
reset()
  Reset the status of the remote POP3 server. This includes resetting the status of all messages to not be deleted.
quit()
  Quit and close the connection to the remote POP3 server. Any messages marked as deleted will be deleted from the remote mailbox.
can_inet6()
  Returns whether we can use IPv6.
can_ssl()
  Returns whether we can use SSL.

## Notes

If a "Net::POP3" object goes out of scope before "quit" method is called then the "reset" method will called before the connection is closed. This means that any messages marked to be deleted will not be.

# EXPORTS

None.

# KNOWN BUGS

See <https://rt.cpan.org/Dist/Display.html?Status=Active&Queue=libnet>.

# SEE ALSO

Net::Netrc, Net::Cmd, IO::Socket::SSL.

# AUTHOR

Graham Barr <gbarr@pobox.com <mailto:gbarr@pobox.com>>.

Steve Hay <shay@cpan.org <mailto:shay@cpan.org>> is now maintaining libnet as of version 1.22_02.

# COPYRIGHT

Copyright (C) 1995-2004 Graham Barr. All rights reserved.

Copyright (C) 2013-2016, 2020 Steve Hay. All rights reserved.

# LICENCE

This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself, i.e. under the terms of either the GNU General Public License or the Artistic License, as specified in the LICENCE file.

# VERSION

Version 3.15

# DATE

20 March 2023

# HISTORY

See the Changes file.

2024-05-14 | perl v5.40.1