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In order to explain the use of these hardware features, we explain how
the ECS system of CAL TSS might be re-implemented.
The state of each object will be represented in one or more segments.
A single data segment might suffice for some simple objects, e.g., a
file with a single data block. More complicated objects would be
represented by a capability segment with capabilities for subparts. A
locked capability for the representing segment is then given to user
A user program will call the system with parameters in hardware
registers. Upon entry, the system will pick up the appropriate keys
and unlock each expected parameter. In one step, this will check for
correct parameter type, sufficient access bits, correct unique name at
the specified MOT index; and produces a segment descriptor for the
representation of the object.