How to set custom name of "this" thread?

Question

I want to set the name of the current execution thread in C++ code; the underlying threading library is pthreads.

In case I have the std::thread handle of a thread, I can get the native pthreads handle using std::thread::native_handle, then pass this to pthread_setname_np to set the thread name.

    auto t = std::thread(call_from_thread);
    pthread_setname_np(t.native_handle(), my_thread_name.c_str());

But how can I set the thread name in cases where I do not have the std::thread handle available. For example when the thread is started by some other library, and I am writing a callback that will be executed by that thread, can I write some code within the callback that sets a custom name for the thread executing it?

I know that I can get the current thread std::thread::id object using std::this_thread::get_id. Is there a way to convert this into a pthread native handle that can then be used to set the custom thread name?

Answer 1

Unless portability is wanted, and the target is only POSIX systems with POSIX threads, the id could easily be obtained with pthread_self.