Boost
C++ Libraries
...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
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.
boost::thread and of the various lock types
are now movable.
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).
boost::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.
boost::system_time for absolute timeouts, and
with support for relative timeouts in many cases. boost::xtime
is supported for backwards compatibility only.
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()
and unlock()
member functions, which are used by the lock types.
The list below should cover all changes to the public interface which break backwards compatibility.
boost::try_mutex has been removed, and
the functionality subsumed into boost::mutex. boost::try_mutex is left as a typedef, but is no longer a separate class.
boost::recursive_try_mutex has been removed,
and the functionality subsumed into boost::recursive_mutex. boost::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()
and unlock()
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);
boost::read_write_mutex has been replaced with
boost::shared_mutex.