User`s guide

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Start Host Notification—Function 23
This function enables notifying your Windows HLLAPI application of changes in the Host session
presentation space or Operation Information Area (OIA).
Prerequisite Functions
None.
WinHLLAPI(STARTHOSTNOTIFICATION,lpbyString,lpwLength,
lpwReturnnCode)
WinHLLAPIAsync(hWnd,STARTHOSTNOTIFICATION,lpbyString,
lpwLength,lpwReturnnCode)
Parameter Description
Data String A 7-byte string in the following format:
Byte 1 Short name session ID of the desired Host
session, or space or null for the current Host
session.
Byte 2
Notification mode. “P” for presentation space
update only, “O” for OIA update only, “B”
for both presentation space and OIA updates.
When calling WinHLLAPIAsync, this
position can be “A”.
Bytes 3-6 Not used; no error occurs if an old Windows
HLLAPI application uses these positions.
Byte 7
Reserved or replace with one of the following
if using WinHLLAPIAsync and “A” in byte
2: “P” for presentation space update only,
“O” for OIA update only, “B” for both
presentation space and OIA updates
Data Length Length of Host event buffer (256 recommended).
PS Position NA
Parameter Description
Data String Same as Data String on the call.
Code Description
WHLLOK Host notification enabled.
WHLLNOTCONNECTED The specified Host session is invalid.
WHLLPARAMETERERROR One or more parameters are invalid.
WHLLSYSERROR The function failed due to a system error.
WHLLCANCEL The asynchronous function was cancelled.
Function Call
Call Parameters
Return Parameters
Return Codes