Function OH_PrivateCommand_GetKey 

pub unsafe extern "C" fn OH_PrivateCommand_GetKey(
    command: *mut InputMethod_PrivateCommand,
    key: *mut *const c_char,
    keyLength: *mut usize,
) -> InputMethod_ErrorCode

@brief Get key value from {@link InputMethod_PrivateCommand}.

@param command Represents a pointer to an {@link InputMethod_PrivateCommand} instance which will be get value from. @param key Represents key value. @param keyLength Represents key length. @return Returns a specific error code. {@link IME_ERR_OK} - success. {@link IME_ERR_NULL_POINTER} - unexpected null pointer. Specific error codes can be referenced {@link InputMethod_ErrorCode}. @since 12