XTYP_REQUEST

XTYP_REQUEST 
 

A dynamic data exchange (DDE) server callback function receives the XTYP_REQUEST transaction when a client specifies XTYP_REQUEST in the DdeClientTransaction function. A client uses this transaction to request data from a server.

Parameters

uFmt
Specifies the format in which the server should submit data to the client.
hconv
Handle to the conversation.
hsz1
Handle to the topic name.
hsz2
Handle to the item name.
hdata
Not used.
dwData1
Not used.
dwData2
Not used.

Return Value

The server should call the DdeCreateDataHandle function to create a data handle that identifies the data and then return the handle. The server should return NULL if it is unable to complete the transaction. If the server returns NULL, the client will receive a DDE_FNOTPROCESSED flag.

Remarks

This transaction is filtered if the server application specified the CBF_FAIL_REQUESTS flag in the DdeInitialize function.

If responding to this transaction requires lengthy processing, the server can return the CBR_BLOCK return code to suspend future transactions on the current conversation and then process the transaction asynchronously. When the server has finished and the data is ready to pass to the client, the server can call the DdeEnableCallback function to resume the conversation.

QuickInfo

  Windows NT: Requires version 3.1 or later.
  Windows: Requires Windows 95 or later.
  Windows CE: Unsupported.
  Header: Declared in ddeml.h.

See Also

Dynamic Data Exchange Management Library Overview, Dynamic Data Exchange Management Transactions, DdeClientTransaction, DdeCreateDataHandle, DdeEnableCallback, DdeInitialize