Int 10 Fn 4F4D  - Vesa - Video Cursor Interface Request                    [V]

   AX = 4F4Dh
   BX = number of bytes available for VCI use
   DS:0000h -> buffer for VCI
   ES:DI -> VCI driver callback function

Return: AL = 4Fh if supported
       AH = status
       00h successful
           BX = number of bytes used by VCI
           ES:DI -> VCI request handler
       01h failed
Desc:  allow the VESA BIOS Extensions to cooperate with a pointing-device
     (typically mouse) driver

See Also: AX=4F12h