For decades, the C and C++ standards treated multi-threading and concurrency as something existing outside the standard sphere - in that "target-dependent" world of shades which the "abstract machine" targeted by the standards doesn't cover. The immediate, cold-blooded replies of "C++ doesn't know what a thread is" in mountains of mailing list and newsgroup questions dealing with parallelism will forever serve as a reminder of this past.

Starting a thread in C++11 is as simple as declaring and instantiating a new object. We will analyze a simple multithreaded application to demonstrate how we can use the threads from the C++ standard library.

The behavior of dispatch_once is in the name. It does something once and only once.

It takes two parameters. The first is a predicate that tracks the "once". The second is a block to execute on the first call.

Parallel programming is essential for writing performant applications on modern hardware. You've probably noticed that, in recent years, CPU clock speeds have barely increased. At the same time, dual-core and quad-core computers have become common.

Thread stuff