The BIDISTATM contains a value that determines which status will be changed and which ones are masked.
The following are possible Bidi status mask values:
#define BDSM_HKFLAGS 0x7E7F0000UL
#define BDSM_AUTOPUSH_RTL 0x00000001UL
#define BDSM_AUTOPUSH_LTR 0x00000002UL
#define BDSM_PUSH_ON 0x00000004UL
#define BDSM_DISABLE_INPUT_PROCESSING 0x00000020UL
#define BDSM_ALL ( BDSM_HKFLAGS |
BDSM_AUTOPUSH_RTL |
BDSM_AUTOPUSH_LTR |
BDSM_PUSH_ON |
BDSM_DISABLE_INPUT_PROCESSING )