Protocols common to DdeServer and DdeClient

The following protocols are common to DdeClient and DdeServer:

Timeouts

Both DdeClient and DdeServer objects can associate timeout values with their DDE conversations. Because the VA Smalltalk DDE model is synchronous, the timeout values are used to time out responses to DDE requests across the connection. If a response to a DDE requests timeout, then the value returned from the request message is either nil or false, depending upon the context of the particular request message. In other words, a timeout looks like a failure for the request message. The timeout value can be set with the timeout: message in the following way:

ddeClient timeout: numberOfMilliseconds

or

ddeServer timeout: numberOfMilliseconds

The DdeServerManager also has a timeout: message that sets the timeout value for any new DdeServer connections that are made.

The default timeout value is set to 1000 milliseconds (1 second).

Disconnect

Both the DdeClient and the DdeServer can disconnect the DDE conversation at any time if they are sent the disconnect message:

ddeClient disconnect

or

ddeServer disconnect

Free

Any DdeClient or DdeServerManager must be sent the free message when they are no longer required by their respective applications. This cleans up and releases any operating system resources that these objects have allocated. For example:

ddeClient free.

or

ddeServerManager free.