Method ReadVersion

src/bvar/default_variables.cpp:619–626

struct ReadVersion {
    std::string content;
    ReadVersion() {
        std::ostringstream oss;
        if (butil::read_command_output(oss, "uname -ap") != 0) {
            LOG(ERROR) << "Fail to read kernel version";
            return;
        }
        content.append(oss.str());
    }
};
static void get_kernel_version(std::ostream& os, void*) {
    os << butil::get_leaky_singleton<ReadVersion>()->content;