Platform SDK: Interprocess Communications

XTYP_REGISTER

A DDE callback function, DdeCallback, receives the XTYP_REGISTER transaction type whenever a DDEML server application uses the DdeNameService function to register a service name, or whenever a non-DDEML application that supports the System topic is started.

HDDEDATA CALLBACK DdeCallback(
  UINT uType,     // XTYP_REGISTER
  UINT uFmt,      // clipboard data format
  HCONV hconv,    // handle to the conversation
  HSZ hsz1,       // handle to a string
  HSZ hsz2,       // handle to a string
  HDDEDATA hdata, // handle to a global memory object
  DWORD dwData1,  // transaction-specific data
  DWORD dwData2   // transaction-specific data
);

Parameters

uType
Specifies the transaction type.
uFmt
Not used.
hconv
Not used.
hsz1
Handle to the base service name being registered.
hsz2
Handle to the instance-specific service name being registered.
hdata
Not used.
dwData1
Not used.
dwData2
Not used.

Remarks

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

A application cannot block this transaction type; the CBR_BLOCK return code is ignored.

An application should use the hsz1 parameter to add the service name to the list of servers available to the user. An application should use the hsz2 parameter to identify which application instance has started.

Requirements

  Windows NT/2000: Requires Windows NT 3.1 or later.
  Windows 95/98: Requires Windows 95 or later.
  Header: Declared in Ddeml.h; include Windows.h.

See Also

Dynamic Data Exchange Management Library Overview, Dynamic Data Exchange Management Transactions, DdeInitialize, DdeNameService