ceph/src/boost/libs/coroutine2/doc/overview.qbk

   1 [/
   2           Copyright Oliver Kowalke 2014.
   3  Distributed under the Boost Software License, Version 1.0.
   4     (See accompanying file LICENSE_1_0.txt or copy at
   5           http://www.boost.org/LICENSE_1_0.txt
   6 ]
   7
   8 [section:overview Overview]
   9
  10 __boost_coroutine__ provides templates for generalized subroutines which allow
  11 suspending and resuming execution at certain locations.
  12 It preserves the local state of execution and allows re-entering subroutines more
  13 than once (useful if state must be kept across function calls).
  14
  15 Coroutines can be viewed as a language-level construct providing a special kind
  16 of control flow.
  17
  18 In contrast to threads, which are pre-emptive, __coro__ switches are
  19 cooperative (programmer controls when a switch will happen). The kernel is not
  20 involved in the coroutine switches.
  21
  22 The implementation uses __boost_context__ for context switching.
  23
  24 In order to use the classes and functions described here, you can either include
  25 the specific headers specified by the descriptions of each class or function, or
  26 include the master library header:
  27
  28     #include <boost/coroutine2/all.hpp>
  29
  30 which includes all the other headers in turn.
  31
  32 All functions and classes are contained in the namespace __coro_ns__.
  33
  34 [note This library requires C++11!]
  35
  36 [endsect]