Function CreatePidFile

src/commons/util/util.cpp:703–709

#ifndef WIN32
void CreatePidFile(const fs::path& path, pid_t pid) {
    FILE* file = fopen(path.string().c_str(), "w");
    if (file) {
        fprintf(file, "%d\n", pid);
        fclose(file);
    }
}
#endif

bool RenameOver(boost::filesystem::path src, boost::filesystem::path dest) {