From 8b86348dfacf37761ee49a429cb42aff76866333 Mon Sep 17 00:00:00 2001 From: Victor Stinner Date: Mon, 27 Jan 2014 10:07:50 +0100 Subject: [PATCH] asyncio: document add_signal_handler/remove_signal_handler, add an example for signals --- Doc/library/asyncio-eventloop.rst | 47 +++++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+) diff --git a/Doc/library/asyncio-eventloop.rst b/Doc/library/asyncio-eventloop.rst index 953fa49386c..75df87bbdd0 100644 --- a/Doc/library/asyncio-eventloop.rst +++ b/Doc/library/asyncio-eventloop.rst @@ -325,6 +325,29 @@ Run subprocesses asynchronously using the :mod:`subprocess` module. This method returns a :ref:`coroutine object `. +UNIX signals +------------ + +Availability: UNIX only. + +.. method:: BaseEventLoop.add_signal_handler(signum, callback, \*args) + + Add a handler for a signal. + + Raise :exc:`ValueError` if the signal number is invalid or uncatchable. + Raise :exc:`RuntimeError` if there is a problem setting up the handler. + +.. method:: BaseEventLoop.remove_signal_handler(sig) + + Remove a handler for a signal. + + Return ``True`` if a signal handler was removed, ``False`` if not. + +.. seealso:: + + The :mod:`signal` module. + + Executor -------- @@ -381,3 +404,27 @@ Print ``Hello World`` every two seconds, using a callback:: :ref:`Hello World example using a coroutine `. + +Example: Set signal handlers for SIGINT and SIGTERM +--------------------------------------------------- + +Register handlers for signals :py:data:`SIGINT` and :py:data:`SIGTERM`:: + + import asyncio + import functools + import os + import signal + + def ask_exit(signame): + print("got signal %s: exit" % signame) + loop.stop() + + loop = asyncio.get_event_loop() + for signame in ('SIGINT', 'SIGTERM'): + loop.add_signal_handler(getattr(signal, signame), + functools.partial(ask_exit, signame)) + + print("Event loop running forever, press CTRL+c to interrupt.") + print("pid %s: send SIGINT or SIGTERM to exit." % os.getpid()) + loop.run_forever() +