HP NonStop G-Series - Manual (Page 61)

DDE Functions
Creating Client Applications
110838 Tandem Computers Incorporated 4–5
be no lengthy user dialogs (such as input of data) within the DDE conversation. TMF
transactions must be wholly contained within one DDE conversation.
DDE Terminate Function The DDE Terminate function is used to end a DDE conversation. If you began a
Tandem TMF transaction in a DDE conversation, but you did not end or abort it, then
the TMF transaction will be automatically aborted by the DDE Terminate function.
It is important to end every DDE conversation you start in your client application.
Otherwise, workstation resources will be used and the data communications resources
allocated to your DDE conversation will not be released for use by other DDE
conversations. Many higher level tools and applications (such as Microsoft Visual
Basic and Microsoft Excel) generally have some automatic cleanup of DDE
conversations in the event of failures or halts, but you have to take action to end DDE
conversations in the event of application detected problems.
Syntax
TERMINATE
DDE Execute Function The DDE Execute function causes the Tandem DDE Gateway to execute the
command(s) provided. Note that the DDE protocol standard requires that the
commands to be executed always be enclosed in square brackets [ ].
You can define character parameters (in parentheses) in syntax with quotation marks
or without quotation marks. Where there is more than one character parameter, they
must all be in quotes or they must all be without quotes.
Syntax
[INITIALIZESERVICE(ServiceName)]
[INITIALIZESERVICE("ServiceName")]
[INITIALIZESERVICE(ServiceName, ApplicationName)]
[INITIALIZESERVICE("ServiceName", "ApplicationName")]
[SEND]
[SEND(ByteCount)]
[BEGINTRANSACTION]
[ENDTRANSACTION]
[ABORTTRANSACTION]
[CLEARERROR]
INITIALIZESERVICE Command
The INITIALIZESERVICE command is used to tell the Tandem DDE Gateway what
type of transaction your client application is about to process. This command causes
the Tandem DDE Gateway to allocate buffers that store data items you send with DDE
Poke functions and data items you request with DDE Request functions. The buffers