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std::thread::join

From cppreference.com
< cpp‎ | thread‎ | thread
void join();
(since C++11)

Blocks the current thread until the thread identified by *this finishes its execution.

Contents

[edit] Parameters

(none)

[edit] Return value

(none)

[edit] Preconditions

joinable is true

[edit] Postconditions

joinable is false

[edit] Exceptions

std::system_error if an error occurs.

[edit] Error Conditions

[edit] Example

#include <iostream>
#include <thread>
#include <chrono>
 
void foo()
{
    // simulate expensive operation
    std::this_thread::sleep_for(std::chrono::seconds(1));
}
 
void bar()
{
    // simulate expensive operation
    std::this_thread::sleep_for(std::chrono::seconds(1));
}
 
int main()
{
    std::cout << "starting first helper...\n";
    std::thread helper1(foo);
 
    std::cout << "starting second helper...\n";
    std::thread helper2(bar);
 
    std::cout << "waiting for helpers to finish..." << std::endl;
    helper1.join();
    helper2.join();
 
    std::cout << "done!\n";
}

Output:

starting first helper...
starting second helper...
waiting for helpers to finish...
done!

[edit] See also

permits the thread to execute independently from the thread handle
(public member function) [edit]
checks whether the thread is joinable, i.e. potentially running in parallel context
(public member function) [edit]

[edit] References

  • C++11 standard (ISO/IEC 14882:2011):
  • 30.3.1.5 thread members [thread.thread.member]