INT 60 - RIFS - CLIENT - INSTALLATION CHECK                                     
	AX = 0000h
Return: AX = 1234h if installed
	CF clear
Program: RIFS is the Remote Installable File SystemAn Installable File System which allows non-DOS format media to be used by DOS.	 In most ways, an IFS is very similar to a networked drive, although an IFS would typically be local rather than remote. See also INT 21h Function 52h. by "kyle"
InstallCheck:	test for the signature "RIFS" immediately preceding the
	  interrupt handler
Range:	INT 60 to INT 66 and INT 18,selected by scanning for 0000h:0000h vector
SeeAlso: AX=0001h,AX=0005h,AX=0007h,AX=0008h,INT 2F/AX=5600h