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Revision 1.35 by root, Sat Nov 10 05:31:48 2007 UTC vs.
Revision 1.47 by root, Fri Nov 23 13:08:55 2007 UTC

41 my ($w, $revents) = @_; 41 my ($w, $revents) = @_;
42 my $status = $w->rstatus; 42 my $status = $w->rstatus;
43 }; 43 };
44 44
45 # MAINLOOP 45 # MAINLOOP
46 EV::loop; # loop until EV::loop_done is called or all watchers stop 46 EV::loop; # loop until EV::unloop is called or all watchers stop
47 EV::loop EV::LOOP_ONESHOT; # block until at least one event could be handled 47 EV::loop EV::LOOP_ONESHOT; # block until at least one event could be handled
48 EV::loop EV::LOOP_NONBLOCK; # try to handle same events, but do not block 48 EV::loop EV::LOOP_NONBLOCK; # try to handle same events, but do not block
49 49
50=head1 DESCRIPTION 50=head1 DESCRIPTION
51 51
57package EV; 57package EV;
58 58
59use strict; 59use strict;
60 60
61BEGIN { 61BEGIN {
62 our $VERSION = '0.7'; 62 our $VERSION = '1.2';
63 use XSLoader; 63 use XSLoader;
64 XSLoader::load "EV", $VERSION; 64 XSLoader::load "EV", $VERSION;
65} 65}
66 66
67@EV::Io::ISA = 67@EV::Io::ISA =
93 93
94Returns the time the last event loop iteration has been started. This 94Returns the time the last event loop iteration has been started. This
95is the time that (relative) timers are based on, and refering to it is 95is the time that (relative) timers are based on, and refering to it is
96usually faster then calling EV::time. 96usually faster then calling EV::time.
97 97
98=item $method = EV::ev_method 98=item $method = EV::method
99 99
100Returns an integer describing the backend used by libev (EV::METHOD_SELECT 100Returns an integer describing the backend used by libev (EV::METHOD_SELECT
101or EV::METHOD_EPOLL). 101or EV::METHOD_EPOLL).
102 102
103=item EV::loop [$flags] 103=item EV::loop [$flags]
104 104
105Begin checking for events and calling callbacks. It returns when a 105Begin checking for events and calling callbacks. It returns when a
106callback calls EV::loop_done. 106callback calls EV::unloop.
107 107
108The $flags argument can be one of the following: 108The $flags argument can be one of the following:
109 109
110 0 as above 110 0 as above
111 EV::LOOP_ONESHOT block at most once (wait, but do not loop) 111 EV::LOOP_ONESHOT block at most once (wait, but do not loop)
112 EV::LOOP_NONBLOCK do not block at all (fetch/handle events but do not wait) 112 EV::LOOP_NONBLOCK do not block at all (fetch/handle events but do not wait)
113 113
114=item EV::loop_done [$how] 114=item EV::unloop [$how]
115 115
116When called with no arguments or an argument of 1, makes the innermost 116When called with no arguments or an argument of EV::UNLOOP_ONE, makes the
117call to EV::loop return. 117innermost call to EV::loop return.
118 118
119When called with an agrument of 2, all calls to EV::loop will return as 119When called with an argument of EV::UNLOOP_ALL, all calls to EV::loop will return as
120fast as possible. 120fast as possible.
121
122=item EV::once $fh_or_undef, $events, $timeout, $cb->($events)
123
124This function rolls together an I/O and a timer watcher for a single
125one-shot event without the need for managing a watcher object.
126
127If C<$fh_or_undef> is a filehandle or file descriptor, then C<$events>
128must be a bitset containing either C<EV::READ>, C<EV::WRITE> or C<EV::READ
129| EV::WRITE>, indicating the type of I/O event you want to wait for. If
130you do not want to wait for some I/O event, specify C<undef> for
131C<$fh_or_undef> and C<0> for C<$events>).
132
133If timeout is C<undef> or negative, then there will be no
134timeout. Otherwise a EV::timer with this value will be started.
135
136When an error occurs or either the timeout or I/O watcher triggers, then
137the callback will be called with the received event set (in general
138you can expect it to be a combination of C<EV:ERROR>, C<EV::READ>,
139C<EV::WRITE> and C<EV::TIMEOUT>).
140
141EV::once doesn't return anything: the watchers stay active till either
142of them triggers, then they will be stopped and freed, and the callback
143invoked.
121 144
122=back 145=back
123 146
124=head2 WATCHER 147=head2 WATCHER
125 148
258Calls the callback after C<$after> seconds. If C<$repeat> is non-zero, 281Calls the callback after C<$after> seconds. If C<$repeat> is non-zero,
259the timer will be restarted (with the $repeat value as $after) after the 282the timer will be restarted (with the $repeat value as $after) after the
260callback returns. 283callback returns.
261 284
262This means that the callback would be called roughly after C<$after> 285This means that the callback would be called roughly after C<$after>
263seconds, and then every C<$repeat> seconds. "Roughly" because the time of 286seconds, and then every C<$repeat> seconds. The timer does his best not
264callback processing is not taken into account, so the timer will slowly 287to drift, but it will not invoke the timer more often then once per event
265drift. If that isn't acceptable, look at EV::periodic. 288loop iteration, and might drift in other cases. If that isn't acceptable,
289look at EV::periodic, which can provide long-term stable timers.
266 290
267The timer is based on a monotonic clock, that is if somebody is sitting 291The timer is based on a monotonic clock, that is, if somebody is sitting
268in front of the machine while the timer is running and changes the system 292in front of the machine while the timer is running and changes the system
269clock, the timer will nevertheless run (roughly) the same time. 293clock, the timer will nevertheless run (roughly) the same time.
270 294
271The C<timer_ns> variant doesn't start (activate) the newly created watcher. 295The C<timer_ns> variant doesn't start (activate) the newly created watcher.
272 296
277 301
278=item $w->again 302=item $w->again
279 303
280Similar to the C<start> method, but has special semantics for repeating timers: 304Similar to the C<start> method, but has special semantics for repeating timers:
281 305
306If the timer is active and non-repeating, it will be stopped.
307
282If the timer is active and repeating, reset the timeout to occur 308If the timer is active and repeating, reset the timeout to occur
283C<$repeat> seconds after now. 309C<$repeat> seconds after now.
284 310
285If the timer is active and non-repeating, it will be stopped.
286
287If the timer is in active and repeating, start it. 311If the timer is inactive and repeating, start it using the repeat value.
288 312
289Otherwise do nothing. 313Otherwise do nothing.
290 314
291This behaviour is useful when you have a timeout for some IO 315This behaviour is useful when you have a timeout for some IO
292operation. You create a timer object with the same value for C<$after> and 316operation. You create a timer object with the same value for C<$after> and
336possible time where C<$time = $at (mod $interval)>, regardless of any time 360possible time where C<$time = $at (mod $interval)>, regardless of any time
337jumps. 361jumps.
338 362
339=item * manual reschedule mode ($reschedule_cb = coderef) 363=item * manual reschedule mode ($reschedule_cb = coderef)
340 364
341In this mode $interval and $at are both being ignored. Instead, each time 365In this mode $interval and $at are both being ignored. Instead, each
342the periodic watcher gets scheduled, the first callback ($reschedule_cb) 366time the periodic watcher gets scheduled, the reschedule callback
343will be called with the watcher as first, and the current time as second 367($reschedule_cb) will be called with the watcher as first, and the current
344argument. 368time as second argument.
345 369
346I<This callback MUST NOT stop or destroy this or any other periodic 370I<This callback MUST NOT stop or destroy this or any other periodic
347watcher, ever>. If you need to stop it, return 1e30 and stop it 371watcher, ever>. If you need to stop it, return 1e30 and stop it
348afterwards. 372afterwards.
349 373
492 # do nothing unless active 516 # do nothing unless active
493 $dispatcher->{_event_queue_h} 517 $dispatcher->{_event_queue_h}
494 or return; 518 or return;
495 519
496 # make the dispatcher handle any outstanding stuff 520 # make the dispatcher handle any outstanding stuff
521 ... not shown
497 522
498 # create an IO watcher for each and every socket 523 # create an IO watcher for each and every socket
499 @snmp_watcher = ( 524 @snmp_watcher = (
500 (map { EV::io $_, EV::READ, sub { } } 525 (map { EV::io $_, EV::READ, sub { } }
501 keys %{ $dispatcher->{_descriptors} }), 526 keys %{ $dispatcher->{_descriptors} }),
527
528 EV::timer +($event->[Net::SNMP::Dispatcher::_ACTIVE]
529 ? $event->[Net::SNMP::Dispatcher::_TIME] - EV::now : 0),
530 0, sub { },
502 ); 531 );
503
504 # if there are any timeouts, also create a timer
505 push @snmp_watcher, EV::timer $event->[Net::SNMP::Dispatcher::_TIME] - EV::now, 0, sub { }
506 if $event->[Net::SNMP::Dispatcher::_ACTIVE];
507 }; 532 };
508 533
509The callbacks are irrelevant, the only purpose of those watchers is 534The callbacks are irrelevant (and are not even being called), the
510to wake up the process as soon as one of those events occurs (socket 535only purpose of those watchers is to wake up the process as soon as
511readable, or timer timed out). The corresponding EV::check watcher will then 536one of those events occurs (socket readable, or timer timed out). The
512clean up: 537corresponding EV::check watcher will then clean up:
513 538
514 our $snmp_check = EV::check sub { 539 our $snmp_check = EV::check sub {
515 # destroy all watchers 540 # destroy all watchers
516 @snmp_watcher = (); 541 @snmp_watcher = ();
517 542
518 # make the dispatcher handle any new stuff 543 # make the dispatcher handle any new stuff
544 ... not shown
519 }; 545 };
520 546
521The callbacks of the created watchers will not be called as the watchers 547The callbacks of the created watchers will not be called as the watchers
522are destroyed before this cna happen (remember EV::check gets called 548are destroyed before this cna happen (remember EV::check gets called
523first). 549first).
526 552
527=back 553=back
528 554
529=head1 THREADS 555=head1 THREADS
530 556
531Threads are not supported by this in any way. Perl pseudo-threads is evil 557Threads are not supported by this module in any way. Perl pseudo-threads
532stuff and must die. 558is evil stuff and must die. As soon as Perl gains real threads I will work
559on thread support for it.
560
561=head1 FORK
562
563Most of the "improved" event delivering mechanisms of modern operating
564systems have quite a few problems with fork(2) (to put it bluntly: it is
565not supported and usually destructive). Libev makes it possible to work
566around this by having a function that recreates the kernel state after
567fork in the child.
568
569On non-win32 platforms, this module requires the pthread_atfork
570functionality to do this automatically for you. This function is quite
571buggy on most BSDs, though, so YMMV. The overhead for this is quite
572negligible, because everything the function currently does is set a flag
573that is checked only when the event loop gets used the next time, so when
574you do fork but not use EV, the overhead is minimal.
575
576On win32, there is no notion of fork so all this doesn't apply, of course.
533 577
534=cut 578=cut
535 579
536our $DIED = sub { 580our $DIED = sub {
537 warn "EV: error in callback (ignoring): $@"; 581 warn "EV: error in callback (ignoring): $@";
542 586
5431; 5871;
544 588
545=head1 SEE ALSO 589=head1 SEE ALSO
546 590
547 L<EV::DNS>, L<EV::AnyEvent>. 591 L<EV::DNS>.
548 592
549=head1 AUTHOR 593=head1 AUTHOR
550 594
551 Marc Lehmann <schmorp@schmorp.de> 595 Marc Lehmann <schmorp@schmorp.de>
552 http://home.schmorp.de/ 596 http://home.schmorp.de/

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