boost_1_45_0/libs/thread/doc/changes.qbk - nest-learning-thermostat/5.0/boost - Git at Google

 [/
   (C) Copyright 2007-8 Anthony Williams.
   Distributed under the Boost Software License, Version 1.0.
   (See accompanying file LICENSE_1_0.txt or copy at
   http://www.boost.org/LICENSE_1_0.txt).
 ]

 [section:changes Changes since boost 1.40]

 The 1.41.0 release of Boost adds futures to the thread library. There are also a few minor changes.

 [heading Changes since boost 1.35]

 The 1.36.0 release of Boost includes a few new features in the thread library:

 * New generic __lock_multiple_ref__ and __try_lock_multiple_ref__ functions for locking multiple mutexes at once.

 * Rvalue reference support for move semantics where the compilers supports it.

 * A few bugs fixed and missing functions added (including the serious win32 condition variable bug).

 * `scoped_try_lock` types are now backwards-compatible with Boost 1.34.0 and previous releases.

 * Support for passing function arguments to the thread function by supplying additional arguments to the __thread__ constructor.

 * Backwards-compatibility overloads added for `timed_lock` and `timed_wait` functions to allow use of `xtime` for timeouts.

 [heading Changes since boost 1.34]

 Almost every line of code in __boost_thread__ has been changed since the 1.34 release of boost. However, most of the interface
 changes have been extensions, so the new code is largely backwards-compatible with the old code. The new features and breaking
 changes are described below.

 [heading New Features]

 * Instances of __thread__ and of the various lock types are now movable.

 * Threads can be interrupted at __interruption_points__.

 * Condition variables can now be used with any type that implements the __lockable_concept__, through the use of
 `boost::condition_variable_any` (`boost::condition` is a `typedef` to `boost::condition_variable_any`, provided for backwards
 compatibility). `boost::condition_variable` is provided as an optimization, and will only work with
 `boost::unique_lock<boost::mutex>` (`boost::mutex::scoped_lock`).

 * Thread IDs are separated from __thread__, so a thread can obtain it's own ID (using `boost::this_thread::get_id()`), and IDs can
 be used as keys in associative containers, as they have the full set of comparison operators.

 * Timeouts are now implemented using the Boost DateTime library, through a typedef `boost::system_time` for absolute timeouts, and
 with support for relative timeouts in many cases. `boost::xtime` is supported for backwards compatibility only.

 * Locks are implemented as publicly accessible templates `boost::lock_guard`, `boost::unique_lock`, `boost::shared_lock`, and
 `boost::upgrade_lock`, which are templated on the type of the mutex. The __lockable_concept__ has been extended to include publicly
 available __lock_ref__ and __unlock_ref__ member functions, which are used by the lock types.

 [heading Breaking Changes]

 The list below should cover all changes to the public interface which break backwards compatibility.

 * __try_mutex__ has been removed, and the functionality subsumed into __mutex__. __try_mutex__ is left as a `typedef`,
 but is no longer a separate class.

 * __recursive_try_mutex__ has been removed, and the functionality subsumed into
 __recursive_mutex__. __recursive_try_mutex__ is left as a `typedef`, but is no longer a separate class.

 * `boost::detail::thread::lock_ops` has been removed. Code that relies on the `lock_ops` implementation detail will no longer work,
 as this has been removed, as it is no longer necessary now that mutex types now have public __lock_ref__ and __unlock_ref__ member
 functions.

 * `scoped_lock` constructors with a second parameter of type `bool` are no longer provided. With previous boost releases,
 ``boost::mutex::scoped_lock some_lock(some_mutex,false);`` could be used to create a lock object that was associated with a mutex,
 but did not lock it on construction. This facility has now been replaced with the constructor that takes a
 `boost::defer_lock_type` as the second parameter: ``boost::mutex::scoped_lock some_lock(some_mutex,boost::defer_lock);``

 * The `locked()` member function of the `scoped_lock` types has been renamed to __owns_lock_ref__.

 * You can no longer obtain a __thread__ instance representing the current thread: a default-constructed __thread__ object is not
 associated with any thread. The only use for such a thread object was to support the comparison operators: this functionality has
 been moved to __thread_id__.

 * The broken `boost::read_write_mutex` has been replaced with __shared_mutex__.

 * __mutex__ is now never recursive. For Boost releases prior to 1.35 __mutex__ was recursive on Windows and not on POSIX platforms.

 * When using a __recursive_mutex__ with a call to [cond_any_wait_link `boost::condition_variable_any::wait()`], the mutex is only
   unlocked one level, and not completely. This prior behaviour was not guaranteed and did not feature in the tests.

 [endsect]
	[/
	(C) Copyright 2007-8 Anthony Williams.
	Distributed under the Boost Software License, Version 1.0.
	(See accompanying file LICENSE_1_0.txt or copy at
	http://www.boost.org/LICENSE_1_0.txt).
	]

	[section:changes Changes since boost 1.40]

	The 1.41.0 release of Boost adds futures to the thread library. There are also a few minor changes.

	[heading Changes since boost 1.35]

	The 1.36.0 release of Boost includes a few new features in the thread library:

	* New generic __lock_multiple_ref__ and __try_lock_multiple_ref__ functions for locking multiple mutexes at once.

	* Rvalue reference support for move semantics where the compilers supports it.

	* A few bugs fixed and missing functions added (including the serious win32 condition variable bug).

	* `scoped_try_lock` types are now backwards-compatible with Boost 1.34.0 and previous releases.

	* Support for passing function arguments to the thread function by supplying additional arguments to the __thread__ constructor.

	* Backwards-compatibility overloads added for `timed_lock` and `timed_wait` functions to allow use of `xtime` for timeouts.

	[heading Changes since boost 1.34]

	Almost every line of code in __boost_thread__ has been changed since the 1.34 release of boost. However, most of the interface
	changes have been extensions, so the new code is largely backwards-compatible with the old code. The new features and breaking
	changes are described below.

	[heading New Features]

	* Instances of __thread__ and of the various lock types are now movable.

	* Threads can be interrupted at __interruption_points__.

	* Condition variables can now be used with any type that implements the __lockable_concept__, through the use of
	`boost::condition_variable_any` (`boost::condition` is a `typedef` to `boost::condition_variable_any`, provided for backwards
	compatibility). `boost::condition_variable` is provided as an optimization, and will only work with
	`boost::unique_lock<boost::mutex>` (`boost::mutex::scoped_lock`).

	* Thread IDs are separated from __thread__, so a thread can obtain it's own ID (using `boost::this_thread::get_id()`), and IDs can
	be used as keys in associative containers, as they have the full set of comparison operators.

	* Timeouts are now implemented using the Boost DateTime library, through a typedef `boost::system_time` for absolute timeouts, and
	with support for relative timeouts in many cases. `boost::xtime` is supported for backwards compatibility only.

	* Locks are implemented as publicly accessible templates `boost::lock_guard`, `boost::unique_lock`, `boost::shared_lock`, and
	`boost::upgrade_lock`, which are templated on the type of the mutex. The __lockable_concept__ has been extended to include publicly
	available __lock_ref__ and __unlock_ref__ member functions, which are used by the lock types.

	[heading Breaking Changes]

	The list below should cover all changes to the public interface which break backwards compatibility.

	* __try_mutex__ has been removed, and the functionality subsumed into __mutex__. __try_mutex__ is left as a `typedef`,
	but is no longer a separate class.

	* __recursive_try_mutex__ has been removed, and the functionality subsumed into
	__recursive_mutex__. __recursive_try_mutex__ is left as a `typedef`, but is no longer a separate class.

	* `boost::detail::thread::lock_ops` has been removed. Code that relies on the `lock_ops` implementation detail will no longer work,
	as this has been removed, as it is no longer necessary now that mutex types now have public __lock_ref__ and __unlock_ref__ member
	functions.

	* `scoped_lock` constructors with a second parameter of type `bool` are no longer provided. With previous boost releases,
	``boost::mutex::scoped_lock some_lock(some_mutex,false);`` could be used to create a lock object that was associated with a mutex,
	but did not lock it on construction. This facility has now been replaced with the constructor that takes a
	`boost::defer_lock_type` as the second parameter: ``boost::mutex::scoped_lock some_lock(some_mutex,boost::defer_lock);``

	* The `locked()` member function of the `scoped_lock` types has been renamed to __owns_lock_ref__.

	* You can no longer obtain a __thread__ instance representing the current thread: a default-constructed __thread__ object is not
	associated with any thread. The only use for such a thread object was to support the comparison operators: this functionality has
	been moved to __thread_id__.

	* The broken `boost::read_write_mutex` has been replaced with __shared_mutex__.

	* __mutex__ is now never recursive. For Boost releases prior to 1.35 __mutex__ was recursive on Windows and not on POSIX platforms.

	* When using a __recursive_mutex__ with a call to [cond_any_wait_link `boost::condition_variable_any::wait()`], the mutex is only
	unlocked one level, and not completely. This prior behaviour was not guaranteed and did not feature in the tests.

	[endsect]