1IO::Async::Loop::Poll(3U)ser Contributed Perl DocumentatiIoOn::Async::Loop::Poll(3)
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6 "IO::Async::Loop::Poll" - use "IO::Async" with "poll(2)"
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9 Normally an instance of this class would not be directly constructed by
10 a program. It may however, be useful for runinng IO::Async with an
11 existing program already using an "IO::Poll" object.
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13 use IO::Poll;
14 use IO::Async::Loop::Poll;
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16 my $poll = IO::Poll->new;
17 my $loop = IO::Async::Loop::Poll->new( poll => $poll );
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19 $loop->add( ... );
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21 while(1) {
22 my $timeout = ...
23 my $ret = $poll->poll( $timeout );
24 $loop->post_poll;
25 }
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28 This subclass of IO::Async::Loop uses the poll(2) system call to
29 perform read-ready and write-ready tests.
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31 By default, this loop will use the underlying "poll()" system call
32 directly, bypassing the usual IO::Poll object wrapper around it because
33 of a number of bugs and design flaws in that class; namely
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35 · <https://rt.cpan.org/Ticket/Display.html?id=93107> - IO::Poll relies
36 on stable stringification of IO handles
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38 · <https://rt.cpan.org/Ticket/Display.html?id=25049> - IO::Poll->poll()
39 with no handles always returns immediately
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41 However, to integrate with existing code that uses an "IO::Poll"
42 object, a "post_poll" can be called immediately after the "poll" method
43 that "IO::Poll" object. The appropriate mask bits are maintained on the
44 "IO::Poll" object when notifiers are added or removed from the loop, or
45 when they change their "want_*" status. The "post_poll" method inspects
46 the result bits and invokes the "on_read_ready" or "on_write_ready"
47 methods on the notifiers.
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50 new
51 $loop = IO::Async::Loop::Poll->new( %args )
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53 This function returns a new instance of a "IO::Async::Loop::Poll"
54 object. It takes the following named arguments:
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56 "poll" The "IO::Poll" object to use for notification. Optional; if a
57 value is not given, the underlying "IO::Poll::_poll()" function
58 is invoked directly, outside of the object wrapping.
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61 post_poll
62 $count = $loop->post_poll
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64 This method checks the returned event list from a "IO::Poll::poll"
65 call, and calls any of the notification methods or callbacks that are
66 appropriate. It returns the total number of callbacks that were
67 invoked; that is, the total number of "on_read_ready" and
68 "on_write_ready" callbacks for "watch_io", and "watch_time" event
69 callbacks.
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71 loop_once
72 $count = $loop->loop_once( $timeout )
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74 This method calls the "poll" method on the stored "IO::Poll" object,
75 passing in the value of $timeout, and then runs the "post_poll" method
76 on itself. It returns the total number of callbacks invoked by the
77 "post_poll" method, or "undef" if the underlying "poll" method returned
78 an error.
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81 Paul Evans <leonerd@leonerd.org.uk>
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85perl v5.32.0 2020-09-24 IO::Async::Loop::Poll(3)