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[/
(C) Copyright 2012 Vicente J. Botet Escriba.
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:tutorial Tutorial]
[@http://web.archive.org/web/20140531071228/http://home.roadrunner.com/~hinnant/mutexes/locking.html Handling mutexes in C++] is an excellent tutorial. You need just replace std and ting by boost.
[@http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2406.html Mutex, Lock, Condition Variable Rationale] adds rationale for the design decisions made for mutexes, locks and condition variables.
In addition to the C++11 standard locks, Boost.Thread provides other locks and some utilities that help the user to make their code thread-safe.
[include internal_locking.qbk]
[include external_locking.qbk]
[section:with Executing Around a Function]
In particular, the library provides a way to lock around the execution of a function.
template <class Lockable, class Function, class... Args>
auto with_lock_guard(
Lockable& m,
Function&& func,
Args&&... args
) -> decltype(func(boost::forward<Args>(args)...)) {
boost::lock_guard<Lockable> lock(m);
return func(boost::forward<Args>(args)...);
}
that can be used with regular functions:
int func(int, int&);
//...
boost::mutex m;
int a;
int result = boost::with_lock_guard(m, func, 1, boost::ref(a));
with boost::bind:
int result = boost::with_lock_guard(
m, boost::bind(func, 2, boost::ref(a))
);
or with lambda expression:
int a;
int result = boost::with_lock_guard(
m,
[&a](int x) {
// this scope is protected by mutex m
a = 3;
return x + 4;
},
5
);
[endsect] [/ With]
[endsect] [/ Tutorial]
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