The MOUSEHOOKSTRUCT structure contains information about a mouse event passed to a WH_MOUSE hook procedure, MouseProc.
typedef struct tagMOUSEHOOKSTRUCT { // ms
POINT pt;
HWND hwnd;
UINT wHitTestCode;
DWORD dwExtraInfo;
} MOUSEHOOKSTRUCT;
Windows NT: Requires version 3.1 or later.
Windows: Requires Windows 95 or later.
Windows CE: Unsupported.
Header: Declared in winuser.h.
Hooks Overview, Hook Structures, MouseProc, POINT, SetWindowsHookEx, WM_NCHITTEST