Boost C++ Libraries

Boost.Thread uses by default Boost.Chrono for the time related functions and define BOOST_THREAD_USES_CHRONO if BOOST_THREAD_DONT_USE_CHRONO is not defined. The user should define BOOST_THREAD_DONT_USE_CHRONO for compilers that don't work well with Boost.Chrono.

	Warning
	When defined BOOST_THREAD_PLATFORM_WIN32 BOOST_THREAD_USES_CHRONO is defined independently of user settings.

Boost.Thread uses by default an internal move semantic implementation. Since version 3.0.0 you can use the move emulation emulation provided by Boost.Move.

When BOOST_THREAD_VERSION==2 define BOOST_THREAD_USES_MOVE if you want to use Boost.Move interface. When BOOST_THREAD_VERSION>=3 define BOOST_THREAD_DONT_USE_MOVE if you don't want to use Boost.Move interface.

The Boost.DateTime time related functions introduced in Boost 1.35.0, using the Boost.Date_Time library are deprecated. These include (but are not limited to):

When BOOST_THREAD_VERSION<=3 && defined BOOST_THREAD_PLATFORM_PTHREAD define BOOST_THREAD_DONT_USE_DATETIME if you don't want to use Boost.DateTime related interfaces. When BOOST_THREAD_VERSION>3 && defined BOOST_THREAD_PLATFORM_PTHREAD define BOOST_THREAD_USES_DATETIME if you want to use Boost.DateTime related interfaces.

	Warning
	When defined BOOST_THREAD_PLATFORM_WIN32 BOOST_THREAD_USES_DATETIME is defined independently of user settings.

Boost.Thread uses by default Boost.Atomic in POSIX platforms to implement call_once..

Define BOOST_THREAD_USES_ATOMIC if you want to use Boost.Atomic. Define BOOST_THREAD_DONT_USE_ATOMIC if you don't want to use Boost.Atomic or if it is not supported in your platform.

The following operators are deprecated:

When BOOST_THREAD_PROVIDES_THREAD_EQ is defined Boost.Thread provides these deprecated feature.

Use instead

	Warning
	This is a breaking change respect to version 1.x.

When BOOST_THREAD_VERSION>=4 define BOOST_THREAD_PROVIDES_THREAD_EQ if you want this feature. When BOOST_THREAD_VERSION<4 define BOOST_THREAD_DONT_PROVIDE_THREAD_EQ if you don't want this feature.

boost::condition is deprecated. When BOOST_THREAD_PROVIDES_CONDITION is defined Boost.Thread provides this deprecated feature.

Use instead boost::condition_variable_any.

	Warning
	This is a breaking change respect to version 1.x.

When BOOST_THREAD_VERSION>3 define BOOST_THREAD_PROVIDES_CONDITION if you want this feature. When BOOST_THREAD_VERSION<=3 define BOOST_THREAD_DONT_PROVIDE_CONDITION if you don't want this feature.

The following nested typedefs are deprecated:

When BOOST_THREAD_PROVIDES_NESTED_LOCKS is defined Boost.Thread provides these deprecated feature.

Use instead * boost::unique_lock<boost::mutex>, * boost::unique_lock<boost::mutex> with the try_to_lock_t constructor, * boost::unique_lock<boost::timed_mutex> * boost::unique_lock<boost::timed_mutex> with the try_to_lock_t constructor * boost::unique_lock<boost::timed_mutex> * boost::unique_lock<boost::recursive_mutex>, * boost::unique_lock<boost::recursive_mutex> with the try_to_lock_t constructor, * boost::unique_lock<boost::recursive_timed_mutex> * boost::unique_lock<boost::recursive_timed_mutex> with the try_to_lock_t constructor * boost::unique_lock<boost::recursive_timed_mutex>

	Warning
	This is a breaking change respect to version 1.x.

When BOOST_THREAD_VERSION>=4 define BOOST_THREAD_PROVIDES_NESTED_LOCKS if you want these features. When BOOST_THREAD_VERSION<4 define BOOST_THREAD_DONT_PROVIDE_NESTED_LOCKS if you don't want thes features.

Boost.Thread uses by default a thread::id on Posix based on the pthread type (BOOST_THREAD_PROVIDES_BASIC_THREAD_ID). For backward compatibility and also for compilers that don't work well with this modification the user can define BOOST_THREAD_DONT_PROVIDE_BASIC_THREAD_ID.

Define BOOST_THREAD_DONT_PROVIDE_BASIC_THREAD_ID if you don't want these features.

The shared mutex implementation on Windows platform provides currently less functionality than the generic one that is used for PTheads based platforms. In order to have access to these functions, the user needs to define BOOST_THREAD_PROVIDES_GENERIC_SHARED_MUTEX_ON_WIN to use the generic implementation, that while could be less efficient, provides all the functions.

When BOOST_THREAD_VERSION==2 define BOOST_THREAD_PROVIDES_GENERIC_SHARED_MUTEX_ON_WIN if you want these features. When BOOST_THREAD_VERSION>=3 define BOOST_THREAD_DONT_PROVIDE_GENERIC_SHARED_MUTEX_ON_WIN if you don't want these features.

Boost.Threads includes in version 3 the Shared Locking Upwards Conversion as defined in Shared Locking. These conversions need to be used carefully to avoid deadlock or livelock. The user need to define explicitly BOOST_THREAD_PROVIDES_SHARED_MUTEX_UPWARDS_CONVERSIONS to get these upwards conversions.

When BOOST_THREAD_VERSION==2 define BOOST_THREAD_PROVIDES_SHARED_MUTEX_UPWARDS_CONVERSIONS if you want these features. When BOOST_THREAD_VERSION>=3 define BOOST_THREAD_DONT_PROVIDE_SHARED_MUTEX_UPWARDS_CONVERSION if you don't want these features.

In Shared Locking the lock conversions are explicit. As this explicit conversion breaks the lock interfaces, it is provided only if the BOOST_THREAD_PROVIDES_EXPLICIT_LOCK_CONVERSION is defined.

When BOOST_THREAD_VERSION==2 define BOOST_THREAD_PROVIDES_EXPLICIT_LOCK_CONVERSION if you want these features. When BOOST_THREAD_VERSION==3 define BOOST_THREAD_DONT_PROVIDE_EXPLICIT_LOCK_CONVERSION if you don't want these features.

C++11 uses std::future. Versions of Boost.Thread previous to version 3.0.0 uses boost:unique_future. Since version 3.0.0 boost::future replaces boost::unique_future when BOOST_THREAD_PROVIDES_FUTURE is defined. The documentation doesn't contains anymore however boost::unique_future.

When BOOST_THREAD_VERSION==2 define BOOST_THREAD_PROVIDES_FUTURE if you want to use boost::future. When BOOST_THREAD_VERSION>=3 define BOOST_THREAD_DONT_PROVIDE_FUTURE if you want to use boost::unique_future.

C++11 promise initialize the associated state at construction time. Versions of Boost.Thread previous to version 3.0.0 initialize it lazily at any point in time in which this associated state is needed.

Since version 3.0.0 this difference in behavior can be configured. When BOOST_THREAD_PROVIDES_PROMISE_LAZY is defined the backward compatible behavior is provided.

When BOOST_THREAD_VERSION==2 define BOOST_THREAD_DONT_PROVIDE_PROMISE_LAZY if you want to use boost::future. When BOOST_THREAD_VERSION>=3 define BOOST_THREAD_PROVIDES_PROMISE_LAZY if you want to use boost::unique_future.

C++11 std::promise provides constructors with allocators.

template <typename R>
class promise
{
  public:
    template <class Allocator>
    explicit promise(allocator_arg_t, Allocator a);
  // ...
};
template <class R, class Alloc> struct uses_allocator<promise<R>,Alloc>: true_type {};

where

struct allocator_arg_t { };
constexpr allocator_arg_t allocator_arg = allocator_arg_t();

template <class T, class Alloc> struct uses_allocator;

Since version 3.0.0 Boost.Thread implements this constructor using the following interface

namespace boost
{
  typedef container::allocator_arg_t allocator_arg_t;
  constexpr allocator_arg_t allocator_arg = {};

  namespace container
  {
    template <class R, class Alloc>
    struct uses_allocator<promise<R>,Alloc>: true_type {};
  }
  template <class T, class Alloc>
  struct uses_allocator : public container::uses_allocator<T, Alloc> {};
}

which introduces a dependency on Boost.Container. This feature is provided only if BOOST_THREAD_PROVIDES_FUTURE_CTOR_ALLOCATORS is defined.

When BOOST_THREAD_VERSION==2 define BOOST_THREAD_PROVIDES_FUTURE_CTOR_ALLOCATORS if you want these features. When BOOST_THREAD_VERSION>=3 define BOOST_THREAD_DONT_PROVIDE_FUTURE_CTOR_ALLOCATORS if you don't want these features.

C++11 has a different semantic for the thread destructor and the move assignment. Instead of detaching the thread, calls to terminate() if the thread was joinable. When BOOST_THREAD_PROVIDES_THREAD_DESTRUCTOR_CALLS_TERMINATE_IF_JOINABLE and BOOST_THREAD_PROVIDES_THREAD_MOVE_ASSIGN_CALLS_TERMINATE_IF_JOINABLE is defined Boost.Thread provides the C++ semantic.

When BOOST_THREAD_VERSION==2 define BOOST_THREAD_PROVIDES_THREAD_DESTRUCTOR_CALLS_TERMINATE_IF_JOINABLE if you want these features. When BOOST_THREAD_VERSION>=3 define BOOST_THREAD_DONT_PROVIDE_THREAD_DESTRUCTOR_CALLS_TERMINATE_IF_JOINABLE if you don't want these features.

When BOOST_THREAD_VERSION==2 define BOOST_THREAD_PROVIDES_THREAD_MOVE_ASSIGN_CALLS_TERMINATE_IF_JOINABLE if you want these features. When BOOST_THREAD_VERSION>=3 define BOOST_THREAD_DONT_PROVIDE_THREAD_MOVE_ASSIGN_CALLS_TERMINATE_IF_JOINABLE if you don't want these features.

C++11 defines a default constructor for once_flag. When BOOST_THREAD_PROVIDES_ONCE_CXX11 is defined Boost.Thread provides this C++ semantics. In this case, the previous aggregate syntax is not supported.

boost::once_flag once = BOOST_ONCE_INIT;

You should now just do

boost::once_flag once;

When BOOST_THREAD_VERSION==2 define BOOST_THREAD_PROVIDES_ONCE_CXX11 if you want these features. When BOOST_THREAD_VERSION>=3 define BOOST_THREAD_DONT_PROVIDE_ONCE_CXX11 if you don't want these features.

C++11 packaged task class has a Signature template parameter. When BOOST_THREAD_PROVIDES_SIGNATURE_PACKAGED_TASK is defined Boost.Thread provides this C++ feature.

	Warning
	This is a breaking change respect to version 3.x.

When BOOST_THREAD_VERSION<4 define BOOST_THREAD_PROVIDES_SIGNATURE_PACKAGED_TASK if you want this feature. When BOOST_THREAD_VERSION>=4 define BOOST_THREAD_DONT_PROVIDE_SIGNATURE_PACKAGED_TASK if you don't want this feature.

C++11 thread constructor accept a variable number of rvalue arguments has. When BOOST_THREAD_PROVIDES_VARIADIC_THREAD is defined Boost.Thread provides this C++ feature if the following are not defined

When BOOST_THREAD_VERSION>4 define BOOST_THREAD_DONT_PROVIDE_VARIADIC_THREAD if you don't want this feature.

C++11 future<>::get() invalidates the future once its value has been obtained. When BOOST_THREAD_PROVIDES_FUTURE_INVALID_AFTER_GET is defined Boost.Thread provides this C++ feature.

	Warning
	This is a breaking change respect to version 3.x.

When BOOST_THREAD_VERSION<4 define BOOST_THREAD_PROVIDES_FUTURE_INVALID_AFTER_GET if you want this feature. When BOOST_THREAD_VERSION>=4 define BOOST_THREAD_DONT_PROVIDE_FUTURE_INVALID_AFTER_GET if you don't want this feature.

Thread interruption, while useful, makes any interruption point less efficient than if the thread were not interruptible.

When BOOST_THREAD_PROVIDES_INTERRUPTIONS is defined Boost.Thread provides interruptions. When BOOST_THREAD_DONT_PROVIDE_INTERRUPTIONS is defined Boost.Thread don't provide interruption.

Boost.Thread defines BOOST_THREAD_PROVIDES_INTERRUPTIONS if neither BOOST_THREAD_PROVIDES_INTERRUPTIONS nor BOOST_THREAD_DONT_PROVIDE_INTERRUPTIONS are defined, so that there is no compatibility break.

BOOST_THREAD_VERSION defines the Boost.Thread version. The default version is 2. In this case the following breaking or extending macros are defined if the opposite is not requested:

The user can request the version 3 by defining BOOST_THREAD_VERSION to 3. In this case the following breaking or extending macros are defined if the opposite is not requested:

The user can request the version 4 by defining BOOST_THREAD_VERSION to 4. In this case the following breaking or extending macros are defined if the opposite is not requested:

If __SUNPRO_CC < 0x5100 the library defines

If __SUNPRO_CC < 0x5100 the library defines

If __IBMCPP__ < 1100 the library defines

And Boost.Thread doesn't links with Boost.Chrono.

If _WIN32_WCE && _WIN32_WCE==0x501 the library defines