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select

This module supports asynchronous I/O on multiple file descriptors.


	
** IMPORTANT NOTICE ***

On Windows, only sockets are supported; on Unix, all file descriptors.

Classes

epoll

select.epoll(sizehint=-1, flags=0)

Returns an epolling object

sizehint must be a positive integer or -1 for the default size. The
sizehint is used to optimize internal data structures. It doesn't limit
the maximum number of monitored events.

close(self, /)

  Close the epoll control file descriptor.

  Further operations on the epoll object will raise an exception.

fileno(self, /)

  Return the epoll control file descriptor.

fromfd(fd, /)

  Create an epoll object from a given control fd.

modify(self, /, fd, eventmask)

  Modify event mask for a registered file descriptor.

    fd
      the target file descriptor of the operation
    eventmask
      a bit set composed of the various EPOLL constants

poll(self, /, timeout=None, maxevents=-1)

  Wait for events on the epoll file descriptor.

    timeout
      the maximum time to wait in seconds (as float);
      a timeout of None or -1 makes poll wait indefinitely
    maxevents
      the maximum number of events returned; -1 means no limit

  Returns a list containing any descriptors that have events to report,
  as a list of (fd, events) 2-tuples.

register(self, /, fd)

  Registers a new fd or raises an OSError if the fd is already registered.

    fd
      the target file descriptor of the operation
    eventmask
      a bit set composed of the various EPOLL constants

  The epoll interface supports all file descriptors that support poll.

unregister(self, /, fd)

  Remove a registered file descriptor from the epoll object.

    fd
      the target file descriptor of the operation

closed = <attribute 'closed' of 'select.epoll' objects>
  True if the epoll handler is closed

OSError

Base class for I/O related errors.

with_traceback(...)

  Exception.with_traceback(tb) --
      set self.__traceback__ to tb and return self.

args = <attribute 'args' of 'BaseException' objects>

characters_written = <attribute 'characters_written' of 'OSError' objects>

errno = <member 'errno' of 'OSError' objects>
  POSIX exception code

filename = <member 'filename' of 'OSError' objects>
  exception filename

filename2 = <member 'filename2' of 'OSError' objects>
  second exception filename

strerror = <member 'strerror' of 'OSError' objects>
  exception strerror

Functions

poll

poll()

  Returns a polling object.

  This object supports registering and unregistering file descriptors, and then
  polling them for I/O events.

select

select(rlist, wlist, xlist, timeout=None, /)

  Wait until one or more file descriptors are ready for some kind of I/O.

  The first three arguments are iterables of file descriptors to be waited for:
  rlist -- wait until ready for reading
  wlist -- wait until ready for writing
  xlist -- wait for an "exceptional condition"
  If only one kind of condition is required, pass [] for the other lists.

  A file descriptor is either a socket or file object, or a small integer
  gotten from a fileno() method call on one of those.

  The optional 4th argument specifies a timeout in seconds; it may be
  a floating point number to specify fractions of seconds.  If it is absent
  or None, the call will never time out.

  The return value is a tuple of three lists corresponding to the first three
  arguments; each contains the subset of the corresponding file descriptors
  that are ready.

  *** IMPORTANT NOTICE ***
  On Windows, only sockets are supported; on Unix, all file
  descriptors can be used.

Other members

EPOLLERR = 8

EPOLLET = 2147483648

EPOLLEXCLUSIVE = 268435456

EPOLLHUP = 16

EPOLLIN = 1

EPOLLMSG = 1024

EPOLLONESHOT = 1073741824

EPOLLOUT = 4

EPOLLPRI = 2

EPOLLRDBAND = 128

EPOLLRDHUP = 8192

EPOLLRDNORM = 64

EPOLLWRBAND = 512

EPOLLWRNORM = 256

EPOLL_CLOEXEC = 524288

PIPE_BUF = 4096

POLLERR = 8

POLLHUP = 16

POLLIN = 1

POLLMSG = 1024

POLLNVAL = 32

POLLOUT = 4

POLLPRI = 2

POLLRDBAND = 128

POLLRDHUP = 8192

POLLRDNORM = 64

POLLWRBAND = 512

POLLWRNORM = 256