c++ get active thread count

To get the active thread count in C++, you can use the std::thread::hardware_concurrency() function provided by the C++ Standard Library. This function returns the number of threads that are supported by the implementation. Here are the steps to get the active thread count:

1. Include the <thread> header file in your C++ program:

#include <thread>

1. Use the std::thread::hardware_concurrency() function to get the active thread count:

unsigned int activeThreads = std::thread::hardware_concurrency();

The std::thread::hardware_concurrency() function returns an unsigned int value representing the number of concurrent threads supported by the implementation. The value returned by this function may not necessarily correspond to the number of physical cores on the system, but it can be used as an estimate of the number of threads that can be executed concurrently.

1. Print the active thread count:

std::cout << "Active Thread Count: " << activeThreads << std::endl;

This will output the active thread count to the console.

Here's a complete example:

#include <iostream>
#include <thread>

int main() {
    unsigned int activeThreads = std::thread::hardware_concurrency();
    std::cout << "Active Thread Count: " << activeThreads << std::endl;
    return 0;
}

When you run this program, it will display the active thread count on the console. Keep in mind that the actual number of active threads may vary depending on the system and other factors.