std::thread::joinable
bool joinable() const; | ? | (since C++11) |
|---|
Checks if the thread object identifies an active thread of execution. Specifically, returns true if get_id() != std::thread::id(). So a default constructed thread is not joinable.
A thread that has finished executing code, but has not yet been joined is still considered an active thread of execution and is therefore joinable.
Parameters
(none).
Return value
true if the thread object identifies an active thread of execution, false otherwise.
Exceptions
noexcept specification:
noexcept
Example
#include <iostream>
#include <thread>
#include <chrono>
void foo()
{
std::this_thread::sleep_for(std::chrono::seconds(1));
}
int main()
{
std::thread t;
std::cout << "before starting, joinable: " << t.joinable() << '\n';
t = std::thread(foo);
std::cout << "after starting, joinable: " << t.joinable() << '\n';
t.join();
std::cout << "after joining, joinable: " << t.joinable() << '\n';
}Output:
before starting, joinable: 0
after starting, joinable: 1
after joining, joinable: 0See also
get_id (C++11) | returns the id of the thread (public member function) |
|---|---|
join | waits for a thread to finish its execution (public member function) |
detach | permits the thread to execute independently from the thread handle (public member function) |
References
- C++11 standard (ISO/IEC 14882:2011):
- 30.3.1.5 thread members thread.thread.member
? cppreference.comLicensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.
本文档系腾讯云开发者社区成员共同维护，如有问题请联系 cloudcommunity@tencent.com
