DRV_SetEntryPoints

Registers a device or DLL to receive pen data at each interrupt. Such pen data include pen packets and any OEM-specific information.

• If the message processing is successful, the driver returns the device hook ID. The ID is a positive number that the sender should store. (To discontinue receiving pen events, the sender must provide the ID number with the DRV_RemoveEntryPoints message.) If the message processing is not successful, the driver returns DRV_FAILURE.

lParam1

Either the PENREG_WILLHANDLEMOUSE flag or the PENREG_DEFAULT flag.

lParam2

The address of a callback function to receive the pen data. This function must export the interface specified in the ProcessTabletEvents function specified elsewhere in this reference section.

The callback routine that handles tablet events must be in a page-locked code segment because it functions as an interrupt-handling routine.

Typically, only the PENWIN.DLL library sends the DRV_SetEntryPoints message to the pen driver. If another process needs to hook the interrupt data traffic, it should do so by sending DRV_SetEntryPoints. Possible reasons to hook the interrupt data include processing pen packets to determine hardware accuracy, recording interrupt-time information, or perhaps performing interrupt-time processing based on pen information.

The following example code shows a call to SendDriverMessage that sends a DRV_SetEntryPoints message.

dwHookID = SendDriverMessage( hPenDrv, DRV_SetEntryPoints,
              PENREG_DEFAULT, &ProcessTabletEvents );