.. function:: devpoll()
- (Only supported on Solaris and derivatives.) Returns a ``/dev/poll``
+ Returns a ``/dev/poll``
polling object; see section :ref:`devpoll-objects` below for the
methods supported by devpoll objects.
.. versionchanged:: 3.4
The new file descriptor is now non-inheritable.
+ .. availability:: Solaris.
+
.. function:: epoll(sizehint=-1, flags=0)
- (Only supported on Linux 2.5.44 and newer.) Return an edge polling object,
+ Return an edge polling object,
which can be used as Edge or Level Triggered interface for I/O
events.
When CPython is built, this function may be disabled using
:option:`--disable-epoll`.
+ .. availability:: Linux >= 2.5.44.
+
.. function:: poll()
- (Not supported by all operating systems.) Returns a polling object, which
+ Returns a polling object, which
supports registering and unregistering file descriptors, and then polling them
for I/O events; see section :ref:`poll-objects` below for the methods supported
by polling objects.
+ .. availability:: Unix.
+
.. function:: kqueue()
- (Only supported on BSD.) Returns a kernel queue object; see section
+ Returns a kernel queue object; see section
:ref:`kqueue-objects` below for the methods supported by kqueue objects.
The new file descriptor is :ref:`non-inheritable <fd_inheritance>`.
.. versionchanged:: 3.4
The new file descriptor is now non-inheritable.
+ .. availability:: BSD, macOS.
+
.. function:: kevent(ident, filter=KQ_FILTER_READ, flags=KQ_EV_ADD, fflags=0, data=0, udata=0)
- (Only supported on BSD.) Returns a kernel event object; see section
+ Returns a kernel event object; see section
:ref:`kevent-objects` below for the methods supported by kevent objects.
+ .. availability:: BSD, macOS.
+
.. function:: select(rlist, wlist, xlist, timeout=None)
.. _devpoll-objects:
-``/dev/poll`` Polling Objects
+``/dev/poll`` polling objects
-----------------------------
Solaris and derivatives have ``/dev/poll``. While :c:func:`!select` is
.. _epoll-objects:
-Edge and Level Trigger Polling (epoll) Objects
+Edge and level trigger polling (epoll) objects
----------------------------------------------
https://linux.die.net/man/4/epoll
- *eventmask*
-
- +-------------------------+-----------------------------------------------+
- | Constant | Meaning |
- +=========================+===============================================+
- | :const:`EPOLLIN` | Available for read |
- +-------------------------+-----------------------------------------------+
- | :const:`EPOLLOUT` | Available for write |
- +-------------------------+-----------------------------------------------+
- | :const:`EPOLLPRI` | Urgent data for read |
- +-------------------------+-----------------------------------------------+
- | :const:`EPOLLERR` | Error condition happened on the assoc. fd |
- +-------------------------+-----------------------------------------------+
- | :const:`EPOLLHUP` | Hang up happened on the assoc. fd |
- +-------------------------+-----------------------------------------------+
- | :const:`EPOLLET` | Set Edge Trigger behavior, the default is |
- | | Level Trigger behavior |
- +-------------------------+-----------------------------------------------+
- | :const:`EPOLLONESHOT` | Set one-shot behavior. After one event is |
- | | pulled out, the fd is internally disabled |
- +-------------------------+-----------------------------------------------+
- | :const:`EPOLLEXCLUSIVE` | Wake only one epoll object when the |
- | | associated fd has an event. The default (if |
- | | this flag is not set) is to wake all epoll |
- | | objects polling on a fd. |
- +-------------------------+-----------------------------------------------+
- | :const:`EPOLLRDHUP` | Stream socket peer closed connection or shut |
- | | down writing half of connection. |
- +-------------------------+-----------------------------------------------+
- | :const:`EPOLLRDNORM` | Equivalent to :const:`EPOLLIN` |
- +-------------------------+-----------------------------------------------+
- | :const:`EPOLLRDBAND` | Priority data band can be read. |
- +-------------------------+-----------------------------------------------+
- | :const:`EPOLLWRNORM` | Equivalent to :const:`EPOLLOUT` |
- +-------------------------+-----------------------------------------------+
- | :const:`EPOLLWRBAND` | Priority data may be written. |
- +-------------------------+-----------------------------------------------+
- | :const:`EPOLLMSG` | Ignored. |
- +-------------------------+-----------------------------------------------+
- | :const:`EPOLLWAKEUP` | Prevents sleep during event waiting. |
- +-------------------------+-----------------------------------------------+
+ The *eventmask* is a bit mask using the following constants:
+
+ +-------------------------+------------------------------------------------+
+ | Constant | Meaning |
+ +=========================+================================================+
+ | :const:`EPOLLIN` | Available for read. |
+ +-------------------------+------------------------------------------------+
+ | :const:`EPOLLOUT` | Available for write. |
+ +-------------------------+------------------------------------------------+
+ | :const:`EPOLLPRI` | Urgent data for read. |
+ +-------------------------+------------------------------------------------+
+ | :const:`EPOLLERR` | Error condition happened on the associated fd. |
+ +-------------------------+------------------------------------------------+
+ | :const:`EPOLLHUP` | Hang up happened on the associated fd. |
+ +-------------------------+------------------------------------------------+
+ | :const:`EPOLLET` | Set Edge Trigger behavior, the default is |
+ | | Level Trigger behavior. |
+ +-------------------------+------------------------------------------------+
+ | :const:`EPOLLONESHOT` | Set one-shot behavior. After one event is |
+ | | pulled out, the fd is internally disabled. |
+ +-------------------------+------------------------------------------------+
+ | :const:`EPOLLEXCLUSIVE` | Wake only one epoll object when the |
+ | | associated fd has an event. The default (if |
+ | | this flag is not set) is to wake all epoll |
+ | | objects polling on an fd. |
+ +-------------------------+------------------------------------------------+
+ | :const:`EPOLLRDHUP` | Stream socket peer closed connection or shut |
+ | | down writing half of connection. |
+ +-------------------------+------------------------------------------------+
+ | :const:`EPOLLRDNORM` | Equivalent to :const:`EPOLLIN` |
+ +-------------------------+------------------------------------------------+
+ | :const:`EPOLLRDBAND` | Priority data band can be read. |
+ +-------------------------+------------------------------------------------+
+ | :const:`EPOLLWRNORM` | Equivalent to :const:`EPOLLOUT`. |
+ +-------------------------+------------------------------------------------+
+ | :const:`EPOLLWRBAND` | Priority data may be written. |
+ +-------------------------+------------------------------------------------+
+ | :const:`EPOLLMSG` | Ignored. |
+ +-------------------------+------------------------------------------------+
+ | :const:`EPOLLWAKEUP` | Prevents sleep during event waiting. |
+ +-------------------------+------------------------------------------------+
.. versionadded:: 3.6
:const:`EPOLLEXCLUSIVE` was added. It's only supported by Linux Kernel 4.5
.. method:: epoll.register(fd[, eventmask])
- Register a fd descriptor with the epoll object.
+ Register a file descriptor *fd* with the epoll object.
.. method:: epoll.modify(fd, eventmask)
- Modify a registered file descriptor.
+ Modify a registered file descriptor *fd*.
.. method:: epoll.unregister(fd)
.. _poll-objects:
-Polling Objects
+Polling objects
---------------
The :c:func:`!poll` system call, supported on most Unix systems, provides better
:const:`POLLPRI`, and :const:`POLLOUT`, described in the table below. If not
specified, the default value used will check for all 3 types of events.
- +-------------------+------------------------------------------+
- | Constant | Meaning |
- +===================+==========================================+
- | :const:`POLLIN` | There is data to read |
- +-------------------+------------------------------------------+
- | :const:`POLLPRI` | There is urgent data to read |
- +-------------------+------------------------------------------+
- | :const:`POLLOUT` | Ready for output: writing will not block |
- +-------------------+------------------------------------------+
- | :const:`POLLERR` | Error condition of some sort |
- +-------------------+------------------------------------------+
- | :const:`POLLHUP` | Hung up |
- +-------------------+------------------------------------------+
- | :const:`POLLRDHUP`| Stream socket peer closed connection, or |
- | | shut down writing half of connection |
- +-------------------+------------------------------------------+
- | :const:`POLLNVAL` | Invalid request: descriptor not open |
- +-------------------+------------------------------------------+
+ +-------------------+-------------------------------------------+
+ | Constant | Meaning |
+ +===================+===========================================+
+ | :const:`POLLIN` | There is data to read. |
+ +-------------------+-------------------------------------------+
+ | :const:`POLLPRI` | There is urgent data to read. |
+ +-------------------+-------------------------------------------+
+ | :const:`POLLOUT` | Ready for output: writing will not block. |
+ +-------------------+-------------------------------------------+
+ | :const:`POLLERR` | Error condition of some sort. |
+ +-------------------+-------------------------------------------+
+ | :const:`POLLHUP` | Hung up. |
+ +-------------------+-------------------------------------------+
+ | :const:`POLLRDHUP`| Stream socket peer closed connection, or |
+ | | shut down writing half of connection. |
+ +-------------------+-------------------------------------------+
+ | :const:`POLLNVAL` | Invalid request: descriptor not open. |
+ +-------------------+-------------------------------------------+
Registering a file descriptor that's already registered is not an error, and has
the same effect as registering the descriptor exactly once.
.. _kqueue-objects:
-Kqueue Objects
+Kqueue objects
--------------
.. method:: kqueue.close()
.. _kevent-objects:
-Kevent Objects
+Kevent objects
--------------
https://man.freebsd.org/cgi/man.cgi?query=kqueue&sektion=2
| Constant | Meaning |
+===========================+=============================================+
| :const:`KQ_FILTER_READ` | Takes a descriptor and returns whenever |
- | | there is data available to read |
+ | | there is data available to read. |
+---------------------------+---------------------------------------------+
| :const:`KQ_FILTER_WRITE` | Takes a descriptor and returns whenever |
- | | there is data available to write |
+ | | there is data available to write. |
+---------------------------+---------------------------------------------+
- | :const:`KQ_FILTER_AIO` | AIO requests |
+ | :const:`KQ_FILTER_AIO` | AIO requests. |
+---------------------------+---------------------------------------------+
| :const:`KQ_FILTER_VNODE` | Returns when one or more of the requested |
- | | events watched in *fflag* occurs |
+ | | events watched in *fflag* occurs. |
+---------------------------+---------------------------------------------+
- | :const:`KQ_FILTER_PROC` | Watch for events on a process id |
+ | :const:`KQ_FILTER_PROC` | Watch for events on a process ID. |
+---------------------------+---------------------------------------------+
| :const:`KQ_FILTER_NETDEV` | Watch for events on a network device |
- | | [not available on macOS] |
+ | | (not available on macOS). |
+---------------------------+---------------------------------------------+
| :const:`KQ_FILTER_SIGNAL` | Returns whenever the watched signal is |
- | | delivered to the process |
+ | | delivered to the process. |
+---------------------------+---------------------------------------------+
- | :const:`KQ_FILTER_TIMER` | Establishes an arbitrary timer |
+ | :const:`KQ_FILTER_TIMER` | Establishes an arbitrary timer. |
+---------------------------+---------------------------------------------+
.. attribute:: kevent.flags
Filter action.
- +---------------------------+---------------------------------------------+
- | Constant | Meaning |
- +===========================+=============================================+
- | :const:`KQ_EV_ADD` | Adds or modifies an event |
- +---------------------------+---------------------------------------------+
- | :const:`KQ_EV_DELETE` | Removes an event from the queue |
- +---------------------------+---------------------------------------------+
- | :const:`KQ_EV_ENABLE` | Permits control() to return the event |
- +---------------------------+---------------------------------------------+
- | :const:`KQ_EV_DISABLE` | Disables event |
- +---------------------------+---------------------------------------------+
- | :const:`KQ_EV_ONESHOT` | Removes event after first occurrence |
- +---------------------------+---------------------------------------------+
- | :const:`KQ_EV_CLEAR` | Reset the state after an event is retrieved |
- +---------------------------+---------------------------------------------+
- | :const:`KQ_EV_SYSFLAGS` | internal event |
- +---------------------------+---------------------------------------------+
- | :const:`KQ_EV_FLAG1` | internal event |
- +---------------------------+---------------------------------------------+
- | :const:`KQ_EV_EOF` | Filter specific EOF condition |
- +---------------------------+---------------------------------------------+
- | :const:`KQ_EV_ERROR` | See return values |
- +---------------------------+---------------------------------------------+
+ +---------------------------+----------------------------------------------+
+ | Constant | Meaning |
+ +===========================+==============================================+
+ | :const:`KQ_EV_ADD` | Adds or modifies an event. |
+ +---------------------------+----------------------------------------------+
+ | :const:`KQ_EV_DELETE` | Removes an event from the queue. |
+ +---------------------------+----------------------------------------------+
+ | :const:`KQ_EV_ENABLE` | Permits control() to return the event. |
+ +---------------------------+----------------------------------------------+
+ | :const:`KQ_EV_DISABLE` | Disables event. |
+ +---------------------------+----------------------------------------------+
+ | :const:`KQ_EV_ONESHOT` | Removes event after first occurrence. |
+ +---------------------------+----------------------------------------------+
+ | :const:`KQ_EV_CLEAR` | Reset the state after an event is retrieved. |
+ +---------------------------+----------------------------------------------+
+ | :const:`KQ_EV_SYSFLAGS` | Internal event. |
+ +---------------------------+----------------------------------------------+
+ | :const:`KQ_EV_FLAG1` | Internal event. |
+ +---------------------------+----------------------------------------------+
+ | :const:`KQ_EV_EOF` | Filter-specific EOF condition. |
+ +---------------------------+----------------------------------------------+
+ | :const:`KQ_EV_ERROR` | See return values. |
+ +---------------------------+----------------------------------------------+
.. attribute:: kevent.fflags
- Filter specific flags.
+ Filter-specific flags.
:const:`KQ_FILTER_READ` and :const:`KQ_FILTER_WRITE` filter flags:
+----------------------------+--------------------------------------------+
| Constant | Meaning |
+============================+============================================+
- | :const:`KQ_NOTE_LOWAT` | low water mark of a socket buffer |
+ | :const:`KQ_NOTE_LOWAT` | Low water mark of a socket buffer. |
+----------------------------+--------------------------------------------+
:const:`KQ_FILTER_VNODE` filter flags:
+----------------------------+--------------------------------------------+
| Constant | Meaning |
+============================+============================================+
- | :const:`KQ_NOTE_DELETE` | *unlink()* was called |
+ | :const:`KQ_NOTE_DELETE` | *unlink()* was called. |
+----------------------------+--------------------------------------------+
- | :const:`KQ_NOTE_WRITE` | a write occurred |
+ | :const:`KQ_NOTE_WRITE` | A write occurred. |
+----------------------------+--------------------------------------------+
- | :const:`KQ_NOTE_EXTEND` | the file was extended |
+ | :const:`KQ_NOTE_EXTEND` | The file was extended. |
+----------------------------+--------------------------------------------+
- | :const:`KQ_NOTE_ATTRIB` | an attribute was changed |
+ | :const:`KQ_NOTE_ATTRIB` | An attribute was changed. |
+----------------------------+--------------------------------------------+
- | :const:`KQ_NOTE_LINK` | the link count has changed |
+ | :const:`KQ_NOTE_LINK` | The link count has changed. |
+----------------------------+--------------------------------------------+
- | :const:`KQ_NOTE_RENAME` | the file was renamed |
+ | :const:`KQ_NOTE_RENAME` | The file was renamed. |
+----------------------------+--------------------------------------------+
- | :const:`KQ_NOTE_REVOKE` | access to the file was revoked |
+ | :const:`KQ_NOTE_REVOKE` | Access to the file was revoked. |
+----------------------------+--------------------------------------------+
:const:`KQ_FILTER_PROC` filter flags:
+----------------------------+--------------------------------------------+
| Constant | Meaning |
+============================+============================================+
- | :const:`KQ_NOTE_EXIT` | the process has exited |
+ | :const:`KQ_NOTE_EXIT` | The process has exited. |
+----------------------------+--------------------------------------------+
- | :const:`KQ_NOTE_FORK` | the process has called *fork()* |
+ | :const:`KQ_NOTE_FORK` | The process has called *fork()*. |
+----------------------------+--------------------------------------------+
- | :const:`KQ_NOTE_EXEC` | the process has executed a new process |
+ | :const:`KQ_NOTE_EXEC` | The process has executed a new process. |
+----------------------------+--------------------------------------------+
- | :const:`KQ_NOTE_PCTRLMASK` | internal filter flag |
+ | :const:`KQ_NOTE_PCTRLMASK` | Internal filter flag. |
+----------------------------+--------------------------------------------+
- | :const:`KQ_NOTE_PDATAMASK` | internal filter flag |
+ | :const:`KQ_NOTE_PDATAMASK` | Internal filter flag. |
+----------------------------+--------------------------------------------+
- | :const:`KQ_NOTE_TRACK` | follow a process across *fork()* |
+ | :const:`KQ_NOTE_TRACK` | Follow a process across *fork()*. |
+----------------------------+--------------------------------------------+
- | :const:`KQ_NOTE_CHILD` | returned on the child process for |
- | | *NOTE_TRACK* |
+ | :const:`KQ_NOTE_CHILD` | Returned on the child process for |
+ | | *NOTE_TRACK*. |
+----------------------------+--------------------------------------------+
- | :const:`KQ_NOTE_TRACKERR` | unable to attach to a child |
+ | :const:`KQ_NOTE_TRACKERR` | Unable to attach to a child. |
+----------------------------+--------------------------------------------+
:const:`KQ_FILTER_NETDEV` filter flags (not available on macOS):
+----------------------------+--------------------------------------------+
| Constant | Meaning |
+============================+============================================+
- | :const:`KQ_NOTE_LINKUP` | link is up |
+ | :const:`KQ_NOTE_LINKUP` | Link is up. |
+----------------------------+--------------------------------------------+
- | :const:`KQ_NOTE_LINKDOWN` | link is down |
+ | :const:`KQ_NOTE_LINKDOWN` | Link is down. |
+----------------------------+--------------------------------------------+
- | :const:`KQ_NOTE_LINKINV` | link state is invalid |
+ | :const:`KQ_NOTE_LINKINV` | Link state is invalid. |
+----------------------------+--------------------------------------------+
.. attribute:: kevent.data
- Filter specific data.
+ Filter-specific data.
.. attribute:: kevent.udata
- User defined value.
+ User-defined value.
projects / thirdparty / Python / cpython.git / commitdiff
