HP NonStop G-Series - Manual (Page 112)

User Hook Library
Extending the Tandem DDE Gateway
8–10 110838 Tandem Computers Incorporated
Prototype
BOOL FAR PASCAL TdmgwHookDdeRequest
(HWND hMainWnd, in
unsigned long ulInitializeServiceSerialNumber, in
LPSTR lpServiceName, in
struct tagDdeDictElementData far * pstructElementData, in
WORD cfFormat, in
void far * lpRequestDataElementValue, out
void far * lpBufferOffset, in
struct tagTdmgwErrorMsg far * pstructErrMsg); out
Parameters
Return Value Zero = Error.
Non-zero = No error.
hMainWnd Window handle of Tandem DDE Gateway main
window.
ulInitializeServiceSerialNumber Number incremented with each
INITIALIZESERVICE command. Starts at zero
when the Tandem DDE Gateway is started.
Rolls over to zero after 4,294,967,295.
lpServiceName Current ServiceName object (from
INITIALIZESERVICE command).
pstructElementData Description of current data element. (See the
“Tandem DDE Gateway Dictionary Structure”
topic).
cfFormat Clipboard format of
lpRequestDataElementValue.
lpRequestDataElementValue Address of area for converted data.
lpBufferOffset Address in message buffer of data element in
Tandem data representation.
pstructErrMsg See “Returning Error Messages” earlier in this
section.
TdmgwHookDdeRequestPostConvert
This function may be called when your client application does an element-by-element
DDE Request function.
You must enable the function with TdmgwHookEnableUserHooks function by
returning a value with the TDMGW_HOOK_ENABLE_REQ_POST_CON bit set.
The TdmgwHookDdeRequestPostConvert function is called only if there is an
automatic built-in data conversion between the Tandem data representation for the
current data element and the clipboard format cfFormat. If the
TdmgwHookIsConvSupported function is enabled, then it also must return non-zero