Monitor Implementation

• Conditional-wait construct: x.wait(c);

1. c – integer expression evaluated when the wait operation is executed.
2. value of c (a priority number) stored with the name of the process that is suspended.
3. when x.signal is executed, process with smallest associated priority number is resumed next.

• Check two conditions to establish correctness of system:

1. User processes must always make their calls on the monitor in a correct sequence.
2. Must ensure that an uncooperative process does not ignore the mutual-exclusion gateway provided by the monitor, and try to access the shared resource directly, without using the access protocols.