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Working With the Message Board Workspace

The Message Board is a workspace (that is, an item of the KB-WORKSPACE class) that G2 creates automatically the first time that G2 executes the action:

G2 automatically activates the Message Board when it is created, and it remains active whether the current KB is running or paused.

The currently installed Message Board Parameters system table determines the size and settings for the Message Board.

Shadowing the Message Board Message Handler

When G2 posts a message to the Message Board, it does so by calling a Message Board message handler and passing it the message. The system-defined handler posts the message to the board.

You can shadow the system-defined handler with any procedure that takes one argument of type text. Such a procedure is called a user-defined Message Board message handler. Once registered, such a handler receives all messages that would otherwise go to the system-defined handler and be posted to the Message Board.

If any activity of a user-defined Message Board message handler causes G2 to post a message to the board, the request goes to the system-defined Message Board handler, which posts the message as if no user-defined handler were in effect.

A user-defined Message Board message handler can itself post messages to the Message Board. G2 passes such a request to the system-defined handler, which posts the message just as if no user-defined handler had been registered.

Resetting G2 does not affect handler shadowing: any handler registered remains in effect when G2 restarts.

Note: The following procedures provide low-level message board message handling. More sophisticated techniques are available through GFR. See the G2 Foundation Resources User's Guide for details.

To register a message board handler:

To deregister a message board handler:

To get the message board handler:

Each of these procedures is described in more detail in the G2 System Procedures Reference Manual.

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