Suppose that we replace the wait and signal operations of monitors with a single construct await(B), where B is a general Boolean expression that causes the process executing it to wait until B becomes true.
a. Write a monitor using this scheme to implement the readers--writers prob-lem.
b. Explain why, in general, this construct cannot be implemented efficiently.
c. What restrictions need to be put on the await statement so that it can be implemented efficiently? (Hint: Restrict the generality of B; see
kessels [1977].)