WM_TIMECHANGE

This message occurs when an application makes a change (or set of changes) to the system time. Any application that changes the system time should send this message to all top-level windows.

Parameter

Description

wParam	Is not used.
lParam	Is not used.

Comments

To send the WM_TIMECHANGE message to all top-level windows, an application can use the SendMessage function with the hWnd parameter set to 0xFFFF.