std::recursive_mutex
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                    | Defined in header  <mutex> | ||
| class recursive_mutex; | (since C++11) | |
The recursive_mutex class is a synchronization primitive that can be used to protect shared data from being simultaneously accessed by multiple threads.
recursive_mutex offers exclusive, recursive ownership semantics:
-  A calling thread owns a recursive_mutexfor a period of time that starts when it successfully calls eitherlockortry_lock. During this period, the thread may make additional calls tolockortry_lock. The period of ownership ends when the thread makes a matching number of calls tounlock.
-  When a thread owns a recursive_mutex, all other threads will block (for calls tolock) or receive a false return value (fortry_lock) if they attempt to claim ownership of therecursive_mutex.
-  The maximum number of times that a recursive_mutexmay be locked is unspecified, but after that number is reached, calls tolockwill throw std::system_error and calls totry_lockwill return false.
The behavior of a program is undefined if a recursive_mutex is destroyed while still owned by some thread.  The recursive_mutex class satisfies all requirements of Mutex and StandardLayoutType.
| Contents | 
[edit] Member types
| Member type | Definition | 
| native_handle_type(optional) | implementation-defined | 
[edit] Member functions
| constructs the mutex (public member function) | |
| destroys the mutex (public member function) | |
| not copy-assignable (public member function) | |
| Locking | |
| locks the mutex, blocks if the mutex is not available (public member function) | |
| tries to lock the mutex, returns if the mutex is not available (public member function) | |
| unlocks the mutex (public member function) | |
| Native handle | |
| returns the underlying implementation-defined thread handle (public member function) | |