INT 21 U - OS/2 v1.x FAPI - "DosQMaxEASize" - GET MAXIMUM SIZE OF EXTENDED ATTR
        AH = 6Fh
        ???
Return: ???
Note:   also supported by OS/2 v2.0+ Virtual DOS Machines
SeeAlso: AX=5703h,AX=6C01h,AH=6Eh"OS/2"

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