INT 21 - Novell NetWare 4.6, Alloy NTNX - LOG/LOCK RECORD (FCB)
        AH = BFh
        AL = flags
            bit 0: lock as well as log record
                1: non-exclusive lock
        DS:DX -> opened FCB (see AH=0Fh)
        BX:CX = offset
        BP = lock timeout in timer ticks (1/18 sec)
        SI:DI = length
Return: AL = error code (see AH=BCh)
SeeAlso: AH=C0h"NetWare",AH=C2h"NetWare"