Int 16 Fn 5758  U - Netroom Postnet - Get Old Interrupt Vectors            [m]

   AX = 5758h
   BX = 5859h

Return: CF clear
   DX:BX -> saved copy of interrupt vector table

Note:  the installation check consists of calling this function and comparing
     BX against 5859h on return; if it has changed, POSTNET is installed

See Also: AX=5758h/BX=5858h
Index: installation check;Netroom POSTNET