INT 21 - Novell NetWare - SYNCHRONIZATION SERVICES - GET OR SET LOCK MODE
AH = C6h
AL = subfunction
00h set old "compatibility" mode (default)
01h set new extended locks mode
02h get lock mode
Return: AL = current lock mode
Note:   this function is supported by NetWare 4.6+, Advanced NetWare 1.0+, and
Alloy NTNX
the locking mode should be 01h for NetWare 4.61+ and Advanced
NetWare 1.0+ locking calls, and 00h for all older calls
SeeAlso: AH=C4h,AH=D0h

See also: 21BC

21C6 - Novell NetWare - SYNCHRONIZATION SERVICES - GET OR SET LOCK MODE