Int 2F Fn 48C5  - PCed/assoc - Association Test                            [-]

   AX = 48C5h
   BL = 02h
   DS:SI -> ASCIZ filename

Return: AX = status
       0000h if filename is unknown
       0001h if there is an association defined for the file
   BX destroyed
Program: ASSOC is a resident utility included as part of the PCED package which
     associated files with executable programs based on their extensions

Note:  chains if BL > 02h on entry

See Also: AX=48C0h,AX=48C5h/BL=00h,AX=48C5h/BL=01h