std::shared_mutex

 

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std::shared_mutex

Member functions

shared_mutex::shared_mutex

shared_mutex::~shared_mutex

Exclusive locking

shared_mutex::lock

shared_mutex::try_lock

shared_mutex::unlock

Shared locking

shared_mutex::lock_shared

shared_mutex::try_lock_shared

shared_mutex::unlock_shared

Native handle

shared_mutex::native_handle

 

Defined in header <mutex>
class shared_mutex;		(since C++14)

The shared_mutex class is a synchronization primitive that can be used to protect shared data from being simultaneously accessed by multiple threads. Differently from other mutex types, there are two levels of access:

• shared - several threads can share ownership of the same mutex.

• exclusive - only one thread can own the mutex.

Shared mutexes are usually used in situations, when multiple readers can access the same resource at the same time without causing data races, but only one writer can do so.

In a manner similar to timed_mutex, shared_mutex provides the ability to attempt to claim ownership of a shared_mutex with a timeout via the try_lock_for(), try_lock_until(), try_lock_shared_for(), try_lock_shared_until() methods.

The shared_mutex class is non-copyable.

Member functions

Template:cpp/thread/mutex/dcl list constructorTemplate:cpp/thread/mutex/dcl list lockTemplate:cpp/thread/mutex/dcl list try lockTemplate:cpp/thread/mutex/dcl list try lock forTemplate:cpp/thread/mutex/dcl list try lock untilTemplate:cpp/thread/mutex/dcl list unlockTemplate:cpp/thread/mutex/dcl list lock sharedTemplate:cpp/thread/mutex/dcl list try lock sharedTemplate:cpp/thread/mutex/dcl list try lock shared forTemplate:cpp/thread/mutex/dcl list try lock shared untilTemplate:cpp/thread/mutex/dcl list unlock shared

Exclusive locking

Shared locking