C++17 STL Cookbook

How it works...

This recipe is an extension of the preceding recipe. Instead of synchronizing only one producer with one consumer, we implemented a program that synchronizes M producers with N consumers. On top of that, not only the consumers go to sleep if there are no items for them left, but also the producers go to sleep as soon as the item queue becomes too long.

When multiple consumers wait for the same queue to fill up, then this would generally also work with the consumer code from the one producer/one consumer scenario. As long as only one thread locks the mutex that protects the queue and then takes items out of it, the code is safe. It does not matter how many threads are waiting for the lock at the same time. The same applies ...