select – Wait for Events on a Set of Streams
This module provides functions to wait for events on streams (select streams which are ready for operations).
Pyboard specifics
Polling is an efficient way of waiting for read/write activity on multiple objects. Current objects that support polling are:
Functions
select.poll()
Create an instance of the Poll
class.
select.select(rlist, wlist, xlist[, timeout])
Wait for activity on a set of objects.
This function is provided for compatibility and is not efficient. Usage of Poll
is recommended instead.
class Poll
Methods
poll.register(obj[, eventmask])
Register obj
for polling. eventmask
is logical OR of:
select.POLLIN
- data available for readingselect.POLLOUT
- more data can be writtenselect.POLLERR
- error occurredselect.POLLHUP
- end of stream/connection termination detectedeventmask
defaults toselect.POLLIN | select.POLLOUT
.
poll.unregister(obj)
Unregister obj
from polling.
poll.modify(obj, eventmask)
Modify the eventmask
for obj
.
poll.poll([timeout])
Wait for at least one of the registered objects to become ready. Returns list of (obj
, event
, ...) tuples, event
element specifies which events happened with a stream and is a combination of select.POLL*
constants described above. There may be other elements in tuple, depending on a platform and version, so don’t assume that its size is 2. In case of timeout, an empty list is returned.
Timeout is in milliseconds.