A Tour of C++, 2nd Edition

15

Concurrency

Keep it simple: as simple as possible, but no simpler.

– A. Einstein

• Introduction

• Tasks and threads

• Passing Arguments

• Returning Results

• Sharing Data

• Waiting for Events

• Communicating Tasks

  future and promise; packaged_task; async()

• Advice

15.1 Introduction

Concurrency – the execution of several tasks simultaneously – is widely used to improve throughput (by using several processors for a single computation) or to improve responsiveness (by allowing one part of a program to progress while another is waiting for a response). All modern programming languages provide support for this. The support provided by the C++ standard library is a portable and type-safe variant of what has been used in C++ for more than 20 years and is almost ...