Regarding the motivation of this exercise. Although I am not the original poster, I see there's a need to provide some further background.

The readers-writers problem is an elementary problem in concurrency, and the typical solution involves the use of condition variables. The construct has its origins in 1974/1975 when Hoarse and Hansen formulated the idea of monitors.

The Art of Multiprocessor Programming introduces this problem in Chapter 1. Their example has Alice and Bob place sentences on a billboard one letter at a time.

"Both the mutual exclusion and producer-consumer protocols require waiting: if one participant is subjected to an unexpected delay, so is the other. ... Surprisingly, the readers-writers problem does have solutions that do not require waiting.

The scope of this exercise is no doubt to provide a working demonstration based on the method of condition variables. Again, the wikipedia article should prove informative.

In reply to Re: Threads sharing global variable by Anonymous Monk
in thread Threads sharing global variable by Anonymous Monk

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