GetWindowThreadProcessId function (winuser.h)
Retrieves the identifier of the thread that created the specified window and, optionally, the identifier of the process that created the window.
Syntax
DWORD GetWindowThreadProcessId(
[in] HWND hWnd,
[out, optional] LPDWORD lpdwProcessId
);
Parameters
[in] hWnd
Type: HWND
A handle to the window.
[out, optional] lpdwProcessId
Type: LPDWORD
A pointer to a variable that receives the process identifier. If this parameter is not NULL, GetWindowThreadProcessId copies the identifier of the process to the variable; otherwise, it does not. If the function fails, the value of the variable is unchanged.
Return value
Type: DWORD
If the function succeeds, the return value is the identifier of the thread that created the window. If the window handle is invalid, the return value is zero. To get extended error information, call GetLastError.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Windows 2000 Professional [desktop apps only] |
| Minimum supported server | Windows 2000 Server [desktop apps only] |
| Target Platform | Windows |
| Header | winuser.h (include Windows.h) |
| Library | User32.lib |
| DLL | User32.dll |
| API set | ext-ms-win-ntuser-window-l1-1-0 (introduced in Windows 8) |