std::thread::hardware_concurrency

 

C++

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Thread support library

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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

 

static unsigned hardware_concurrency();		(since C++11)

Returns number of concurrent threads supported by the implementation. The value should be considered only a hint.

Parameters

(none)

Return value

number of concurrent threads supported. If the value is not well defined or not computable, returns ​0​.

Exceptions

noexcept specification:  

noexcept

  

Example

Run this code

#include <iostream>
#include <thread>
 
int main() {
    unsigned int n = std::thread::hardware_concurrency();
    std::cout << n << " concurrent threads are supported.\n";
}

Possible output:

4 concurrent threads are supported.