Embedded Programming with Modern C++ Cookbook

Using condition variables

We learned how to synchronize simultaneous access to the same variable from two or more threads. The particular order in which threads accessed the variable was not important; we only prevented simultaneous reads and writes to the variable.

A thread waiting for another thread to start processing data is a common scenario. In this case, the second thread should be notified by the first thread when the data is available. It can be done using condition variables, supported by C++, starting from the C++11 standard.

In this recipe, we will learn how to use condition variables to activate data processing in a separate thread as soon as the data is available.