# gevent

# `gevent.threading` – Implementation of the standard `threading` using greenlets

Note

This module is a helper for `gevent.monkey` and is not intended to be used directly. For spawning greenlets in your applications, prefer higher level constructs like `gevent.Greenlet` class or `gevent.spawn()`. Attributes in this module like `__threading__` are implementation artifacts subject to change at any time.

Changed in version 1.2.3: Defer adjusting the stdlib’s list of active threads until we are monkey patched. Previously this was done at import time. We are documented to only be used as a helper for monkey patching, so this should functionally be the same, but some applications ignore the documentation and directly import this module anyway.

A positive consequence is that `import gevent.threading, threading; threading.current_thread()` will no longer return a DummyThread before monkey-patching.

class `Thread`(group=None, target=None, name=None, args=(), kwargs=None, *, daemon=None)

  Bases: `threading.Thread`

  This constructor should always be called with keyword arguments. Arguments are:

  group should be None; reserved for future extension when a ThreadGroup class is implemented.

  target is the callable object to be invoked by the run() method. Defaults to None, meaning nothing is called.

  name is the thread name. By default, a unique name is constructed of the form “Thread-N” where N is a small decimal number.

  args is the argument tuple for the target invocation. Defaults to ().

  kwargs is a dictionary of keyword arguments for the target invocation. Defaults to {}.

  If a subclass overrides the constructor, it must make sure to invoke the base class constructor (Thread.__init__()) before doing anything else to the thread.

  `isAlive`()

    Return whether the thread is alive.

    This method returns True just before the run() method starts until just after the run() method terminates. The module function enumerate() returns a list of all alive threads.

  `is_alive`()

    Return whether the thread is alive.

    This method returns True just before the run() method starts until just after the run() method terminates. The module function enumerate() returns a list of all alive threads.

  `join`(timeout=None)

    Wait until the thread terminates.

    This blocks the calling thread until the thread whose join() method is called terminates – either normally or through an unhandled exception or until the optional timeout occurs.

    When the timeout argument is present and not None, it should be a floating point number specifying a timeout for the operation in seconds (or fractions thereof). As join() always returns None, you must call is_alive() after join() to decide whether a timeout happened – if the thread is still alive, the join() call timed out.

    When the timeout argument is not present or None, the operation will block until the thread terminates.

    A thread can be join()ed many times.

    join() raises a RuntimeError if an attempt is made to join the current thread as that would cause a deadlock. It is also an error to join() a thread before it has been started and attempts to do so raises the same exception.

  `run`()

    Method representing the thread’s activity.

    You may override this method in a subclass. The standard run() method invokes the callable object passed to the object’s constructor as the target argument, if any, with sequential and keyword arguments taken from the args and kwargs arguments, respectively.

class `Timer`(interval, function, args=None, kwargs=None)

  Bases: `gevent.threading.Thread`, `threading.Timer`

Next page: `gevent.threadpool` - A pool of native threads