Correspondence Chess via eMail

eMail offers a convenient way to play Correspondence Chess. The standard Unix application is XBoard and its cmail helper - as it has fast email processing, and still maintains PGN compliability. This is also the model which Scid uses. By preserving the whole PGN header, such games can be played with any opponent who has a tool to handle PGN.

Scid too can handle eMail correspondence games almost automatically; maintaining compatiblity with cmail and XBoard. It works by sending the games as PGN attachments, including in the header certain tags that allows them to be recognised and sorted together. For this reason the user has to be careful with editing the header. Fields/tags with explicit values have to be set to exactly to this value. Starting a game with Scid will do this automatically, but you must not overwrite or delete them.

Essential header fields are

• Event: by default "Email correspondence game"
• Site: has to be "NET"
• Mode: has to be "EM"
• WhiteNA: contains the eMail address of the white player. Note that only the bare address is stored there in the form user@host.org.
• BlackNA: contains the eMail address of the black player similar to WhiteNA.
• CmailGameName: Contains a unique identifier for the game. This is used to sort the games together.

  While Scid could use some database index this is not possible for non-DB-based tools like cmail. For this reason the CmailGameName parameter is user suppied. It must be unique! The easiest way is something of the form xx-yy-yyyymmdd where xx is a shortcut for the white player, yy one for the black player, and yyyymmdd the current date.

  For Xfcc-based games this field has also to be set to a unique identifier but there the server name and the unique game number on this server can be used, that is this identifier is of the form MyXfccServer-12345.

eMail based chess does not contain that extended status codes as Xfcc. These games show the icon to notify them as eMail based.

Start a new game

This opens a dialog for the input of the own and the opponents name as they should appear in the header as well as the eMail addresses of both parties. Additionally a unique game ID has to be inserted. The easiest way for this ID is something of the form xx-yy-yyyymmdd where xx is a shortcut for the white player, yy one for the black player, and yyyymmdd the current date. This id is a text and it is important to identify the games uniquely. Users of cmail will also know this ID as game name. It must only contain letters and numbers, the minus sign and the underscore. Please avoid other characters.

After the dialog is quit by pressing the [Ok] button a new game is appended to the currently loaded correspondence chess database and the PGN header is set properly. Just make your move and send it as mentioned below.

Retrieve games

Scid does not handle your mailbox automatically. This would, considering the wide range of possible mail setups these days, involve a huge amount of code. For this reason Scid relies on your normal eMail program which is far more suitable for this purpose than Scid can ever be. To get a game into Scid just save the attached PGN file to Scid's inbox and process the inbox by either Retrieve Games or the button or Process Inbox. The difference between the two is that the first one will also fetch and populate the Inbox additionally with games from another source (say Xfcc) by either the internal Xfcc support or an external fetch tool called. Hence is the most convenient way if you use both types of correspondence chess games.

Note The Retrieve Games menu or the button do not fetch your eMail messages! You have to save your PGN files to Scids Inbox by hand. Probably this can be automatised by your eMail program (on Un*x systems setting up a mime handler is easy enough by means of .mailcap).

NoteBy using the you can empty your whole In- and Outbox directories.

Send the response

After making your move send it by either the Mail Move item from the menu via Send move which is equivalent to . The latter will Scid have to recognise the game as eMail correspondence and send it by mail while the former method will force Scid to generate an eMail message.

Of course Scid strips the the game bare of any comments and variations before attaching it to the outgoing eMail as you probably do not want to send your analysis along.

If a GUI-mailer is used, its usual compose window is opened. The address of your opponent is filled in as well as a generic subject containing the game id for easy filtering and the bcc address if specified in the Configuraion dialog. The mail body is set to contain the FEN of the final position and the list of moves made so far. This way the opponent can quickly look up your move. Finally, Scid attaches the current game including your move in PGN format to the mail message.

When using a mailx compatible tool no window is opened and the mail is sent invisibly by invoking the tool specified in the background. In this case the generated mail contains the PGN also in the mail body.

Note that as eMail chess works by sending the whole PGN file you must not add more than your half move. Scid does not check here wether more than one half move was added to the mainline, simply as Scid does not know which move it was, when you sent yours.