std::unique_lock

Template parameters

Mutex

A mutex-like type.
It shall be a basic lockable type, such as mutex (see BasicLockable for requirements).

Member types

Member functions

(constructor)

Construct unique_lock (public member function)

(destructor)

Destroy unique_lock (public member function)

Locking/unlocking

lock

Lock mutex (public member function)

try_lock

Lock mutex if not locked (public member function)

try_lock_for

Try to lock mutex during time span (public member function)

try_lock_until

Try to lock mutex until time point (public member function)

unlock

Unlock mutex (public member function)

Modifiers

operator=

Move-assign unique_lock (public member function)

swap

Swap unique locks (public member function)

release

Release mutex (public member function)

Observers

owns_lock

Owns lock (public member function)

operator bool

Return whether it owns a lock (public member function)

mutex

Get mutex (public member function)

Non-member overloads

swap (unique_lock)

Swap locks (function)

Example

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// unique_lock example
#include <iostream>       // std::cout
#include <thread>         // std::thread
#include <mutex>          // std::mutex, std::unique_lock
std::mutex mtx;           // mutex for critical section
void print_block (int n, char c) {
  // critical section (exclusive access to std::cout signaled by lifetime of lck):
  std::unique_lock<std::mutex> lck (mtx);
  for (int i=0; i<n; ++i) { std::cout << c; }
  std::cout << '\n';
}
int main ()
{
  std::thread th1 (print_block,50,'*');
  std::thread th2 (print_block,50,'$');
  th1.join();
  th2.join();
  return 0;
}

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