libstdc++ system_error failure sample

system_error_test.cpp

#include <iostream>
#include <system_error>

using namespace std;

void Test1() {
    const auto value = errc::no_such_file_or_directory;
    const auto code = make_error_code(value);
    cout << "value == code: " << (value == code) << "\n";
}

void Test2() {
    error_condition ec = make_error_condition(errc::no_such_file_or_directory);
    auto ec2 = ec.category().default_error_condition(ec.value());
    auto ec3 = ec2.category().default_error_condition(ec.value());
    cout << ec3.category().name() << endl;
}

int main() {
    Test1();
    Test2();
    return 0;
}