The ImmGetOpenStatus function checks whether the IME is open or closed.
BOOL WINAPI ImmGetOpenStatus(
HIMC hIMC
);
The return value is a nonzero value if the IME is open, and zero otherwise.
Windows NT: Requires version 4.0 or later.
Windows: Requires Windows 95 or later.
Windows CE: Requires version 2.0 or later (FE).
Header: Declared in imm.h.
Import Library: Use imm32.lib.
Input Method Editor Overview, Input Method Editor Functions