# Stem Docs

## Version

Tor versioning information and requirements for its features. These can be easily parsed and compared, for instance…

    >>> from stem.version import get_system_tor_version, Requirement
    >>> my_version = get_system_tor_version()
    >>> print(my_version)
    0.2.1.30
    >>> my_version >= Requirement.TORRC_CONTROL_SOCKET
    True

Module Overview:

    get_system_tor_version - gets the version of our system's tor installation

    Version - Tor versioning information

`stem.version.``Requirement`(enum)

  Enumerations for the version requirements of features.

  Deprecated since version 1.6.0: Requirement entries belonging to tor versions which have been obsolete for at least six months will be removed when we break backward compatibility in the 2.x stem release.

  Requirement | Description
  --- | ---
  AUTH_SAFECOOKIE | SAFECOOKIE authentication method
  DESCRIPTOR_COMPRESSION | Expanded compression support for ZSTD and LZMA
  DORMANT_MODE | DORMANT and ACTIVE `Signal`
  DROPGUARDS | DROPGUARDS requests
  EVENT_AUTHDIR_NEWDESCS | AUTHDIR_NEWDESC events
  EVENT_BUILDTIMEOUT_SET | BUILDTIMEOUT_SET events
  EVENT_CIRC_MINOR | CIRC_MINOR events
  EVENT_CLIENTS_SEEN | CLIENTS_SEEN events
  EVENT_CONF_CHANGED | CONF_CHANGED events
  EVENT_DESCCHANGED | DESCCHANGED events
  EVENT_GUARD | GUARD events
  EVENT_HS_DESC_CONTENT | HS_DESC_CONTENT events
  EVENT_NETWORK_LIVENESS | NETWORK_LIVENESS events
  EVENT_NEWCONSENSUS | NEWCONSENSUS events
  EVENT_NS | NS events
  EVENT_SIGNAL | SIGNAL events
  EVENT_STATUS | STATUS_GENERAL, STATUS_CLIENT, and STATUS_SERVER events
  EVENT_STREAM_BW | STREAM_BW events
  EVENT_TRANSPORT_LAUNCHED | TRANSPORT_LAUNCHED events
  EVENT_CONN_BW | CONN_BW events
  EVENT_CIRC_BW | CIRC_BW events
  EVENT_CELL_STATS | CELL_STATS events
  EVENT_TB_EMPTY | TB_EMPTY events
  EVENT_HS_DESC | HS_DESC events
  EXTENDCIRCUIT_PATH_OPTIONAL | EXTENDCIRCUIT queries can omit the path if the circuit is zero
  FEATURE_EXTENDED_EVENTS | ‘EXTENDED_EVENTS’ optional feature
  FEATURE_VERBOSE_NAMES | ‘VERBOSE_NAMES’ optional feature
  GETINFO_CONFIG_TEXT | ‘GETINFO config-text’ query
  GETINFO_GEOIP_AVAILABLE | ‘GETINFO ip-to-country/ipv4-available’ query and its ipv6 counterpart
  GETINFO_MICRODESCRIPTORS | ‘GETINFO md/all’ query
  GETINFO_UPTIME | ‘GETINFO uptime’ query
  HIDDEN_SERVICE_V3 | Support for v3 hidden services
  HSFETCH | HSFETCH requests
  HSFETCH_V3 | HSFETCH for version 3 hidden services
  HSPOST | HSPOST requests
  ADD_ONION | ADD_ONION and DEL_ONION requests
  ADD_ONION_BASIC_AUTH | ADD_ONION supports basic authentication
  ADD_ONION_NON_ANONYMOUS | ADD_ONION supports non-anonymous mode
  ADD_ONION_MAX_STREAMS | ADD_ONION support for MaxStreamsCloseCircuit
  LOADCONF | LOADCONF requests
  MICRODESCRIPTOR_IS_DEFAULT | Tor gets microdescriptors by default rather than server descriptors
  SAVECONF_FORCE | Added the ‘FORCE’ flag to SAVECONF
  TAKEOWNERSHIP | TAKEOWNERSHIP requests
  TORRC_CONTROL_SOCKET | ‘ControlSocket <path>’ config option
  TORRC_PORT_FORWARDING | ‘PortForwarding’ config option
  TORRC_DISABLE_DEBUGGER_ATTACHMENT | ‘DisableDebuggerAttachment’ config option
  TORRC_VIA_STDIN | Allow torrc options via ‘tor -f -‘ (ticket 13865)