HP NonStop G-Series - Manual (Page 111)

User Hook Library
Extending the Tandem DDE Gateway
110838 Tandem Computers Incorporated 8–9
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 lpPokeDataElementValue.
lpPokeDataElementValue Data value being sent with the DDE Poke to be
converted. Data is in the clipboard format
cfFormat.
pstructErrMsg See “Returning Error Messages” earlier in this
section.
TdmgwHookDdeRequest This function may be called when your client application does an element-by-element
DDE Request function.
The function is called when the previous call to TdmgwHookIsConvSupported returns
non-zero in both the pbSupportedFormat and pbConvertWithOnlyHookCode
parameters.
Convert the value in Tandem data representation at lpBufferOffset to the clipboard
format cfFormat and store it in the memory area pointed to by the parameter
lpRequestDataElementValue. Details of the data element (for example, element name,
size, data type) are in the tagDdeDictElementData structure pointed to by
pstructElementData.
You must specify the length of the data area pointed to by the parameter
lpRequestDataElementValue by using the TdmgwHookGetRequestDdeSize User
Hook Library function.