Get Raspberry Pi serial number

serial.cpp

#include <iostream>
#include <fstream>
#include <sstream>
#include <cstdint>
#include <iomanip>
#include <experimental/optional>

/*
 * Get Raspberry Pi serial number
 */
std::experimental::optional<std::uint32_t> get_serial() {
    std::ifstream finfo("/proc/cpuinfo");
    std::string line;
    while (std::getline(finfo, line)) {
        if (line.substr(0, 6) == "Serial") {
            std::stringstream ss;
            ss << std::hex << line.substr(10, 26);
            std::uint32_t serial;
            ss >> serial;
            if (!ss.fail()) {
                return serial;
            }
        }
    }
    return {};
}

int main() {
    auto serial = get_serial();
    if (serial) {
        std::cout << std::hex << std::setw(16) << std::setfill('0') << *serial << std::endl;
    } else {
        std::cout << "fail to get serial" << std::endl;
    }
}