# Extending Sylpheed-Claws

## Provided plugins

Sylpheed-Claws' capabilities are extended by plugins. It comes with the plugins listed below included, all of which are built automatically if the required libraries are present.

Plugins are installed in $PREFIX/lib/sylpheed-claws/plugins/ and have a suffix of .so. To load a plugin go to Configuration/Plugins and click the Load Plugin button. Select the plugin that you want and click OK.

If you don't find the plugin you're looking for, it is possible that your GNU/Linux distribution provides it in a separate package. In this case, search for the plugin in your package manager.

Clam Antivirus

  Enables the scanning of message attachments in mail received from a POP, IMAP or LOCAL account using Clam AntiVirus. It can optionally delete the mail or save it to a designated folder. Preferences can be found in Configuration/Preferences/Plugins/Clam AntiVirus. Clam AntiVirus is available from http://clamav.sourceforge.net/.

Dillo HTML Viewer

  Enables the viewing of html messages using the Dillo web browser, version 0.7.0 or newer. It uses Dillo's --local option by default for safe browsing. Preferences can be found in /Configuration/Preferences/Plugins/Dillo Browser. Dillo is available from http://www.dillo.org/.

PGP/Core, PGP/Inline and PGP/MIME

  Handles PGP signed and/or encrypted mails. You can decrypt mails, verify signatures or sign and encrypt your own mails. Uses GnuPG/GPGME, ftp://ftp.gnupg.org/gcrypt/gpgme/.

SpamAssassin

  The SpamAssassin plugin comes with two major features:

  The ability to scan incoming mail received from a POP, IMAP or LOCAL account using SpamAssassin. It can optionally delete mail identified as spam or save it to a designated folder. Mail scanning can be turned off, which is useful if your email is scanned on your server.

  The ability for users to teach SpamAssassin to recognise spam or ham. You can train SpamAssassin by marking messages as spam or ham from the Message List contextual menu, or using the relevant toolbar button in the main window or the message window (see "Configuration/Preferences/Customize toolbars"). Messages marked as spam are optionally saved to a designated folder.

  Plugin preferences can be found in "Configuration/Preferences/Plugins/SpamAssassin".

  SpamAssassin is available from http://spamassassin.apache.org/. Version 3.1.x or higher is required to use the learning feature in TCP mode.

Trayicon

  Places an icon in the system tray that indicates whether you have any new mail. A tooltip also shows the current new, unread and total number of messages.

## More plugins

Other plugins have been written too, which are available as separate downloads. At the time of this writing, there are a number of plugins available at http://www.sylpheed-claws.net/plugins.php:

Acpi Notifier

  Enables new mail notification via the LEDs found on some laptops like Acer, Asus, Fujitsu and IBM laptops.

AttRemover

  This plugin lets you remove attachments from emails.

CacheSaver

  Saves the caches every 60 seconds (or user-defined period). It helps avoiding the loss of metadata if your computer (or Sylpheed-Claws!) crashes.

etpan! Privacy

  Handles signature verification and decryption of encrypted messages in S/MIME, OpenPGP and ascii-armored PGP formats. Doesn't handle passphrases.

Fetchinfo

  Inserts headers containing some download information, like UIDL, Sylpheed-Claws' account name, POP server, user ID and retrieval time.

GtkHtml Viewer

  Like Dillo, enables the viewing of html messages, but in a nicer way (antialiased fonts).

Maildir

  Provides direct support for Maildir++ mailboxes. With this plugin you can share your Maildir++ mailbox with other mailers or IMAP servers.

mailMBOX

  Handles mailboxes in mbox format.

Perl

  Intended to extend the filtering possibilities of Sylpheed-Claws. It provides a Perl interface to Sylpheed-Claws' filtering mechanism, allowing the use of full Perl power in email filters.

S/MIME

  Handles S/MIME signed and/or encrypted mails. You can decrypt mails, verify signatures or sign and encrypt your own mails. Uses GnuPG/GPGME and GpgSM, ftp://ftp.gnupg.org/gcrypt/gpgme/.

SynCE

  Assists in keeping the address book of a Windows CE device (Pocket PC/ iPAQ, Smartphone etc) in sync with Sylpheed-Claws' address book, with respect to email addresses.

vCalendar

  Enables vCalendar message handling like that produced by Evolution or Outlook, and Webcal subscriptions.

RSSyl

  Allows you to read your favorite newsfeeds in Claws. RSS 1.0, 2.0 and Atom feeds are currently supported.

If you're a developer, writing a plugin to extend Sylpheed-Claws' capabilities is probably the best and easiest solution. We will provide hosting to your code, and will be glad to answer your questions in the mailing-list or the IRC channel, #sylpheed on IRCnet.

## Network access from the plugins

Some of the external plugins, for example RSSyl, vCalendar or GtkHtml Viewer, need Internet access for their operations (retrieving feeds in the case of RSSyl or vCalendar, and fetching images in the case of GtkHtml Viewer). These plugins use the Curl library. Hence, if your Internet access is restricted by a proxy, you will need to tell libCurl to use this proxy. This is done by setting an environment variable, http_proxy. For example, http_proxy=http://user:passwd@myproxy.example.com:8080 will tell libCurl to connect to port 8080 of the machine myproxy.example.com, with the user user and password passwd to connect to the Internet.

You can either set this variable before starting Sylpheed-Claws, by using for example http_proxy=http://user:passwd@myproxy.example.com:8080 sylpheed-claws, or set it in your ~/.bashrc file, by adding the following line: export http_proxy=http://user:passwd@myproxy.example.com:8080 (you'll have to reconnect to have it taken into account).