...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
Boost.Coroutine provides templates for generalized subroutines which allow suspending and resuming execution at certain locations. It preserves the local state of execution and allows re-entering subroutines more than once (useful if state must be kept across function calls).
Coroutines can be viewed as a language-level construct providing a special kind of control flow.
In contrast to threads, which are pre-emptive, coroutine switches are cooperative (programmer controls when a switch will happen). The kernel is not involved in the coroutine switches.
The implementation uses Boost.Context for context switching.
In order to use the classes and functions described here, you can either include the specific headers specified by the descriptions of each class or function, or include the master library header:
#include <boost/coroutine/all.hpp>
which includes all the other headers in turn.
All functions and classes are contained in the namespace boost::coroutines.