Docs and one small improvement for issue #25304, by Vincent Michel. (Merge 3.4->3.5.)

Doc/library/asyncio-dev.rst

@@ -96,10 +96,9 @@ the same thread. But when the task uses ``yield from``, the task is suspended
 and the event loop executes the next task.
 
 To schedule a callback from a different thread, the
-:meth:`BaseEventLoop.call_soon_threadsafe` method should be used. Example to
-schedule a coroutine from a different thread::
+:meth:`BaseEventLoop.call_soon_threadsafe` method should be used. Example::
 
-    loop.call_soon_threadsafe(asyncio.ensure_future, coro_func())
+    loop.call_soon_threadsafe(callback, *args)
 
 Most asyncio objects are not thread safe. You should only worry if you access
 objects outside the event loop. For example, to cancel a future, don't call
@@ -110,6 +109,13 @@ directly its :meth:`Future.cancel` method, but::
 To handle signals and to execute subprocesses, the event loop must be run in
 the main thread.
 
+To schedule a coroutine object from a different thread, the
+:func:`run_coroutine_threadsafe` function should be used. It returns a
+:class:`concurrent.futures.Future` to access the result::
+
+     future = asyncio.run_coroutine_threadsafe(coro_func(), loop)
+     result = future.result(timeout)  # Wait for the result with a timeout
+
 The :meth:`BaseEventLoop.run_in_executor` method can be used with a thread pool
 executor to execute a callback in different thread to not block the thread of
 the event loop.