The modules described in this chapter provide interfaces to operating system features that are available on selected operating systems only. The interfaces are generally modelled after the Unix or C interfaces but they are available on some other systems as well (e.g. Windows or NT). Here's an overview:
| signal | Set handlers for asynchronous events. |
| socket | Low-level networking interface. |
| select | Wait for I/O completion on multiple streams. |
| thread | Create multiple threads of control within one interpreter. |
| threading | Higher-level threading interface. |
| Queue | A synchronized queue class. |
| anydbm | Generic interface to DBM-style database modules. |
| dumbdbm | Portable implementation of the simple DBM interface. |
| dbhash | DBM-style interface to the BSD database library. |
| whichdb | Guess which DBM-style module created a given database. |
| bsddb | Interface to Berkeley DB database library |
| zlib | Low-level interface to compression and decompression routines compatible with gzip. |
| gzip | Interfaces for gzip compression and decompression using file objects. |
| rlcompleter | Python identifier completion in the readline library. |