The WM_SETBIDISTAT message is optionally sent to a window procedure every time a window bidirectional status word is set. Likewise, the WM_QUERYBIDISTAT can be sent when the status is queried. This lets a bidi-aware window procedure know that its status is being change and to take the appropriate action, if required. In general, these messages are sent and processed in the same way as the WM_SETBIDIATTR and WM_QUERYBIDIATTR message, as described in the "Sending WM_SETBIDIATTR messages in WinSetLangInfo API".