This call allows a graphics mode application to be notified when it must restore its video mode, state, and modified display adapter registers. The return from this function call provides the notification.
VioModeWait (RequestType, NotifyType, Reserved)
RequestType (USHORT) - input Application request event. RequestType = 0 indicates the application wants to be notified at the end of a pop-up to restore its mode. RequestType = 0 is the only event supported by VioModeWait.
NotifyType (PUSHORT) - output Address of the operation to be performed by the application returning from VioModeWait. NotifyType = 0, indicating restore mode, is the only type of notification returned.
Reserved (USHORT) - input Reserved word of 0s.
rc (USHORT) - return Return code descriptions are:
| 0 | NO_ERROR |
| 421 | ERROR_VIO_INVALID_PARMS |
| 422 | ERROR_VIO_FUNCTION_OWNED |
| 423 | ERROR_VIO_RETURN |
| 424 | ERROR_SCS_INVALID_FUNCTION |
| 428 | ERROR_VIO_NO_SAVE_RESTORE_THD |
| 430 | ERROR_VIO_ILLEGAL_DURING_POPUP |
| 465 | ERROR_VIO_DETACHED |
| 494 | ERROR_VIO_EXTENDED_SG |
Remarks
At the completion of an application or hard error pop-up (reference VioPopUp), OS/2 notifies the session that was originally interrupted for the pop-up to restore its mode. The return from this function call provides that notification. The thread that issued the call must perform the restore and then immediately re-issue VioModeWait.
When an application's VioModeWait thread is notified, the thread must restore its video mode, state, and modified display adapter registers. An application's VioModeWait thread does not restore the physical display buffer. OS/2 saves/restores the physical display buffer over a pop-up.
Only one process for a session can issue VioModeWait. The first process that issues VioModeWait becomes the owner of this function. (Refer to VioModeUndo.)
An application must issue VioModeWait only if it writes directly to the registers on the display adapter. Otherwise, the application can allow OS/2 to perform the required restore by not issuing VioModeWait.
When an application issues VioModeWait, it is also required to issue VioSavRedrawWait to be notified at screen switch time to perform a full save or restore (reference VioSavRedrawWait. Two application threads must be dedicated to performing these operations.
#define INCL_VIO USHORT rc = VioModeWait(RequestType, NotifyType, Reserved); USHORT RequestType; /* Request type */ PUSHORT NotifyType; /* Notify type (returned) */ USHORT Reserved; /* Reserved (must be zero) */ USHORT rc; /* return code */
EXTRN VioModeWait:FAR INCL_VIO EQU 1 PUSH WORD RequestType ;Request type PUSH@ WORD NotifyType ;Notify type (returned) PUSH WORD Reserved ;Reserved (must be zero) CALL VioModeWait Returns WORD