WM_SYSDEADCHAR
wDeadKey = wParam; /* dead-key character */
cRepeat = (int) LOWORD(lParam); /* repeat count */
cAutoRepeat = HIWORD(lParam); /* autorepeat count */
The WM_SYSDEADCHAR message is sent to the window with the input focus when WM_SYSKEYUP and WM_SYSKEYDOWN messages are translated. It specifies the character value of a dead key.
wDeadKey
Value of wParam. Specifies the dead-key character value.
cRepeat
Value of the low-order word of lParam. Specifies the repeat count.
cAutoRepeat
Value of the high-order word of lParam. Specifies the auto-repeat count.
An application should return zero if it processes this message.