std::thread::detach

 

C++

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Regular expressions library (C++11)

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Thread support library

Threads
thread (C++11)
this_thread namespace
get_id (C++11) yield (C++11)	sleep_for (C++11) sleep_until (C++11)
Mutual exclusion
mutex (C++11) timed_mutex (C++11)	recursive_mutex (C++11) recursive_timed_mutex (C++11)
Generic lock management
lock_guard (C++11) unique_lock (C++11) defer_lock_t try_to_lock_t adopt_lock_t (C++11) (C++11) (C++11)	lock (C++11) try_lock (C++11) defer_lock try_to_lock adopt_lock (C++11) (C++11) (C++11)
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condition_variable (C++11)
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std::thread

Member classes

thread::id

Member functions

thread::thread

thread::~thread

thread::operator=

Observers

thread::joinable

thread::get_id

thread::native_handle

thread::hardware_concurrency

Operations

thread::join

thread::detach

thread::swap

Non-member functions

std::swap

 

void detach();		(since C++11)

Separates the thread of execution from the thread object, allowing execution to continue independently. Any allocated resources will be freed once the thread exits.

After calling detach, the following conditions will hold:

• *this no longer owns any thread
• joinable() == false
• get_id() == std::thread::id()

Parameters

(none)

Return value

(none)

Exceptions

std::system_error if joinable() == false or an error occurs.

Example

run this code

#include <iostream>
#include <chrono>
#include <thread>
 
void independentThread() 
{
    std::cout << "Starting concurrent thread.\n";
    std::this_thread::sleep_for(std::chrono::seconds(2));
    std::cout << "Exiting concurrent thread.\n";
}
 
void threadCaller() 
{
    std::cout << "Starting thread caller.\n";
    std::thread t(independentThread);
    t.detach();
    std::this_thread::sleep_for(std::chrono::seconds(1));
    std::cout << "Exiting thread caller.\n";
}
 
int main() 
{
    threadCaller();
    std::this_thread::sleep_for(std::chrono::seconds(5));
}

Possible output:

Starting thread caller.
Starting concurrent thread.
Exiting thread caller.
Exiting concurrent thread.

See also

join	waits for a thread to finish its execution (public member function)
joinable	checks whether the thread is joinable, i.e. potentially running in parallel context (public member function)