INT 15 C - OS HOOK - DEVICE OPEN (ATIBM PC AT,XT286IBM PC XT/286,PSIBM PS/2, any model)
	AH = 80h
	BX = device ID
	CX = process ID
	CF clear
Return: CF clear if successful
	    AH = 00h
	CF set on error
	    AH = status (see #00496)
Note:	this function should be hooked by a multitasker which wishes to keep
	  track of device ownership; the default BIOS(Basic Input/Output System) A set of standardized calls giving low-level access to the hardware.  The BIOS is the lowest software layer above the actual hardware and serves to insulate programs (and operating systems) which use it from the details of accessing the hardware directly. handler merely returns
	  successfully
SeeAlso: AH=81h,AH=82h


(Table 00496)
Values for status:
 80h	invalid command (PCIBM PC,PCjr)
 86h	function not supported (XTIBM PC XT)