The WM_MOVE message is sent after a window has been moved.
WM_MOVE
xPos = (int)(short) LOWORD(lParam); // horizontal position
yPos = (int)(short) HIWORD(lParam); // vertical position
If an application processes this message, it should return zero.
The xPos and yPos parameters are given in screen coordinates for overlapped and pop-up windows and in parent-client coordinates for child windows.
An application can use the MAKEPOINTS macro to convert the lParam parameter to a POINTS structure.
Windows NT: Requires version 3.1 or later.
Windows: Requires Windows 95 or later.
Windows CE: Requires version 1.0 or later.
Header: Declared in winuser.h.
Windows Overview, Window Messages, MAKEPOINTS, POINTS