class PidFileWiper {
public:
    ~PidFileWiper() {
        if (path.empty()) {
            return;
        }

        ofstream out(path.c_str(), ios_base::out);
        out.close();
    }

    bool write(const string& p) {
        path = p;
        ofstream out(path.c_str(), ios_base::out);
        out << ProcessId::getCurrent() << endl;
        return out.good();
    }

    string path;
} pidFileWiper;

bool writePidFile(const string& path) {
    bool e = pidFileWiper.write(path);
    if (!e) {
        log() << "ERROR: Cannot write pid file to " << path << ": " << strerror(errno);
    }
    return e;
}