Module threading

A factory function that returns a new bounded semaphore.

A bounded semaphore checks to make sure its current value doesn't exceed its initial value. If it does, ValueError is raised. In most situations semaphores are used to guard resources with limited capacity.

If the semaphore is released too many times it's a sign of a bug. If not given, value defaults to 1.

Like regular semaphores, bounded semaphores manage a counter representing the number of release() calls minus the number of acquire() calls, plus an initial value. The acquire() method blocks if necessary until it can return without making the counter negative. If not given, value defaults to 1.

Factory function that returns a new condition variable object.

A condition variable allows one or more threads to wait until they are notified by another thread.

If the lock argument is given and not None, it must be a Lock or RLock object, and it is used as the underlying lock. Otherwise, a new RLock object is created and used as the underlying lock.

A factory function that returns a new event.

Events manage a flag that can be set to true with the set() method and reset to false with the clear() method. The wait() method blocks until the flag is true.

(allocate() is an obsolete synonym)

Create a new lock object. See help(LockType) for information about locks.

Returns: lock object

Factory function that returns a new reentrant lock.

A reentrant lock must be released by the thread that acquired it. Once a thread has acquired a reentrant lock, the same thread may acquire it again without blocking; the thread must release it once for each time it has acquired it.

A factory function that returns a new semaphore.

Semaphores manage a counter representing the number of release() calls minus the number of acquire() calls, plus an initial value. The acquire() method blocks if necessary until it can return without making the counter negative. If not given, value defaults to 1.

Factory function to create a Timer object.

Timers call a function after a specified number of seconds:

    t = Timer(30.0, f, args=[], kwargs={})
    t.start()
    t.cancel()     # stop the timer's action if it's still waiting

Return the number of Thread objects currently alive.

The returned count is equal to the length of the list returned by enumerate().

Return the number of Thread objects currently alive.

The returned count is equal to the length of the list returned by enumerate().

Return the current Thread object, corresponding to the caller's thread of control.

If the caller's thread of control was not created through the threading module, a dummy thread object with limited functionality is returned.

Return the current Thread object, corresponding to the caller's thread of control.

If the caller's thread of control was not created through the threading module, a dummy thread object with limited functionality is returned.

Return a list of all Thread objects currently alive.

The list includes daemonic threads, dummy thread objects created by current_thread(), and the main thread. It excludes terminated threads and threads that have not yet been started.

Set a profile function for all threads started from the threading module.

The func will be passed to sys.setprofile() for each thread, before its run() method is called.

Set a trace function for all threads started from the threading module.

The func will be passed to sys.settrace() for each thread, before its run() method is called.

Return the thread stack size used when creating new threads.  The
optional size argument specifies the stack size (in bytes) to be used
for subsequently created threads, and must be 0 (use platform or
configured default) or a positive integer value of at least 32,768 (32k).
If changing the thread stack size is unsupported, a ThreadError
exception is raised.  If the specified size is invalid, a ValueError
exception is raised, and the stack size is unmodified.  32k bytes
 currently the minimum supported stack size value to guarantee
sufficient stack space for the interpreter itself.

Note that some platforms may have particular restrictions on values for
the stack size, such as requiring a minimum stack size larger than 32kB or
requiring allocation in multiples of the system memory page size
- platform documentation should be referred to for more information
(4kB pages are common; using multiples of 4096 for the stack size is
the suggested approach in the absence of more specific information).

Returns: size