| .. _someos: | 
 |  | 
 | ********************************** | 
 | Optional Operating System Services | 
 | ********************************** | 
 |  | 
 | The modules described in this chapter provide interfaces to operating system | 
 | features that are available on selected operating systems only. The interfaces | 
 | are generally modeled after the Unix or C interfaces but they are available on | 
 | some other systems as well (e.g. Windows).  Here's an overview: | 
 |  | 
 |  | 
 | .. toctree:: | 
 |  | 
 |    select.rst | 
 |    threading.rst | 
 |    multiprocessing.rst | 
 |    concurrent.futures.rst | 
 |    mmap.rst | 
 |    readline.rst | 
 |    rlcompleter.rst | 
 |    dummy_threading.rst | 
 |    _thread.rst | 
 |    _dummy_thread.rst |