NAME¶

std::jthread::native_handle - std::jthread::native_handle

Synopsis¶

[[nodiscard]] native_handle_type native_handle(); (since C++20)
(not always present)

Returns the implementation defined underlying thread handle.

Parameters¶

(none)

Return value¶

Implementation defined handle type representing the thread.

Exceptions¶

May throw implementation-defined exceptions.

Example¶

Uses native_handle to enable realtime scheduling of C++ threads on a POSIX system.

// Run this code

#include <chrono>
#include <cstring>
#include <iostream>
#include <mutex>
#include <pthread.h>
#include <thread>

std::mutex iomutex;
void f(int num)
{
std::this_thread::sleep_for(std::chrono::seconds(1));

sched_param sch;
int policy;
pthread_getschedparam(pthread_self(), &policy, &sch);
std::lock_guard<std::mutex> lk(iomutex);
std::cout << "Thread " << num << " is executing at priority "
<< sch.sched_priority << '\n';
}

int main()
{
std::jthread t1(f, 1), t2(f, 2);

sched_param sch;
int policy;
pthread_getschedparam(t1.native_handle(), &policy, &sch);
sch.sched_priority = 20;
if (pthread_setschedparam(t1.native_handle(), SCHED_FIFO, &sch))
std::cout << "Failed to setschedparam: " << std::strerror(errno) << '\n';

}

Output:¶

Thread 2 is executing at priority 0
Thread 1 is executing at priority 20