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Comparing EV/EV.pm (file contents):
Revision 1.35 by root, Sat Nov 10 05:31:48 2007 UTC vs.
Revision 1.51 by root, Sat Nov 24 16:12:37 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 = '1.3';
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 =
68@EV::Timer::ISA = 68@EV::Timer::ISA =
69@EV::Periodic::ISA = 69@EV::Periodic::ISA =
70@EV::Signal::ISA = 70@EV::Signal::ISA =
71@EV::Idle::ISA = 71@EV::Idle::ISA =
72@EV::Prepare::ISA = 72@EV::Prepare::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, $cb->($revents)
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
210watchers with higher priority will be invoked first. The valid range of 233watchers with higher priority will be invoked first. The valid range of
211priorities lies between EV::MAXPRI (default 2) and EV::MINPRI (default 234priorities lies between EV::MAXPRI (default 2) and EV::MINPRI (default
212-2). If the priority is outside this range it will automatically be 235-2). If the priority is outside this range it will automatically be
213normalised to the nearest valid priority. 236normalised to the nearest valid priority.
214 237
215The default priority of any newly-created weatcher is 0. 238The default priority of any newly-created watcher is 0.
239
240Note that the priority semantics have not yet been fleshed out and are
241subject to almost certain change.
216 242
217=item $w->trigger ($revents) 243=item $w->trigger ($revents)
218 244
219Call the callback *now* with the given event mask. 245Call the callback *now* with the given event mask.
220 246
247=item $previous_state = $w->keepalive ($bool)
248
249Normally, C<EV::loop> will return when there are no active watchers
250(which is a "deadlock" because no progress can be made anymore). This is
251convinient because it allows you to start your watchers (and your jobs),
252call C<EV::loop> once and when it returns you know that all your jobs are
253finished (or they forgot to register some watchers for their task :).
254
255Sometimes, however, this gets in your way, for example when you the module
256that calls C<EV::loop> (usually the main program) is not the same module
257as a long-living watcher (for example a DNS client module written by
258somebody else even). Then you might want any outstanding requests to be
259handled, but you would not want to keep C<EV::loop> from returning just
260because you happen to have this long-running UDP port watcher.
261
262In this case you can clear the keepalive status, which means that even
263though your watcher is active, it won't keep C<EV::loop> from returning.
264
265The initial value for keepalive is true (enabled), and you cna change it
266any time.
267
268Example: Register an IO watcher for some UDP socket but do not keep the
269event loop from running just because of that watcher.
270
271 my $udp_socket = ...
272 my $udp_watcher = EV::io $udp_socket, EV::READ, sub { ... };
273 $udp_watcher->keepalive (0);
221 274
222=item $w = EV::io $fileno_or_fh, $eventmask, $callback 275=item $w = EV::io $fileno_or_fh, $eventmask, $callback
223 276
224=item $w = EV::io_ns $fileno_or_fh, $eventmask, $callback 277=item $w = EV::io_ns $fileno_or_fh, $eventmask, $callback
225 278
258Calls the callback after C<$after> seconds. If C<$repeat> is non-zero, 311Calls the callback after C<$after> seconds. If C<$repeat> is non-zero,
259the timer will be restarted (with the $repeat value as $after) after the 312the timer will be restarted (with the $repeat value as $after) after the
260callback returns. 313callback returns.
261 314
262This means that the callback would be called roughly after C<$after> 315This means that the callback would be called roughly after C<$after>
263seconds, and then every C<$repeat> seconds. "Roughly" because the time of 316seconds, and then every C<$repeat> seconds. The timer does his best not
264callback processing is not taken into account, so the timer will slowly 317to drift, but it will not invoke the timer more often then once per event
265drift. If that isn't acceptable, look at EV::periodic. 318loop iteration, and might drift in other cases. If that isn't acceptable,
319look at EV::periodic, which can provide long-term stable timers.
266 320
267The timer is based on a monotonic clock, that is if somebody is sitting 321The 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 322in front of the machine while the timer is running and changes the system
269clock, the timer will nevertheless run (roughly) the same time. 323clock, the timer will nevertheless run (roughly) the same time.
270 324
271The C<timer_ns> variant doesn't start (activate) the newly created watcher. 325The C<timer_ns> variant doesn't start (activate) the newly created watcher.
272 326
277 331
278=item $w->again 332=item $w->again
279 333
280Similar to the C<start> method, but has special semantics for repeating timers: 334Similar to the C<start> method, but has special semantics for repeating timers:
281 335
336If the timer is active and non-repeating, it will be stopped.
337
282If the timer is active and repeating, reset the timeout to occur 338If the timer is active and repeating, reset the timeout to occur
283C<$repeat> seconds after now. 339C<$repeat> seconds after now.
284 340
285If the timer is active and non-repeating, it will be stopped.
286
287If the timer is in active and repeating, start it. 341If the timer is inactive and repeating, start it using the repeat value.
288 342
289Otherwise do nothing. 343Otherwise do nothing.
290 344
291This behaviour is useful when you have a timeout for some IO 345This behaviour is useful when you have a timeout for some IO
292operation. You create a timer object with the same value for C<$after> and 346operation. You create a timer object with the same value for C<$after> and
336possible time where C<$time = $at (mod $interval)>, regardless of any time 390possible time where C<$time = $at (mod $interval)>, regardless of any time
337jumps. 391jumps.
338 392
339=item * manual reschedule mode ($reschedule_cb = coderef) 393=item * manual reschedule mode ($reschedule_cb = coderef)
340 394
341In this mode $interval and $at are both being ignored. Instead, each time 395In this mode $interval and $at are both being ignored. Instead, each
342the periodic watcher gets scheduled, the first callback ($reschedule_cb) 396time the periodic watcher gets scheduled, the reschedule callback
343will be called with the watcher as first, and the current time as second 397($reschedule_cb) will be called with the watcher as first, and the current
344argument. 398time as second argument.
345 399
346I<This callback MUST NOT stop or destroy this or any other periodic 400I<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 401watcher, ever>. If you need to stop it, return 1e30 and stop it
348afterwards. 402afterwards.
349 403
492 # do nothing unless active 546 # do nothing unless active
493 $dispatcher->{_event_queue_h} 547 $dispatcher->{_event_queue_h}
494 or return; 548 or return;
495 549
496 # make the dispatcher handle any outstanding stuff 550 # make the dispatcher handle any outstanding stuff
551 ... not shown
497 552
498 # create an IO watcher for each and every socket 553 # create an IO watcher for each and every socket
499 @snmp_watcher = ( 554 @snmp_watcher = (
500 (map { EV::io $_, EV::READ, sub { } } 555 (map { EV::io $_, EV::READ, sub { } }
501 keys %{ $dispatcher->{_descriptors} }), 556 keys %{ $dispatcher->{_descriptors} }),
557
558 EV::timer +($event->[Net::SNMP::Dispatcher::_ACTIVE]
559 ? $event->[Net::SNMP::Dispatcher::_TIME] - EV::now : 0),
560 0, sub { },
502 ); 561 );
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 }; 562 };
508 563
509The callbacks are irrelevant, the only purpose of those watchers is 564The callbacks are irrelevant (and are not even being called), the
510to wake up the process as soon as one of those events occurs (socket 565only 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 566one of those events occurs (socket readable, or timer timed out). The
512clean up: 567corresponding EV::check watcher will then clean up:
513 568
514 our $snmp_check = EV::check sub { 569 our $snmp_check = EV::check sub {
515 # destroy all watchers 570 # destroy all watchers
516 @snmp_watcher = (); 571 @snmp_watcher = ();
517 572
518 # make the dispatcher handle any new stuff 573 # make the dispatcher handle any new stuff
574 ... not shown
519 }; 575 };
520 576
521The callbacks of the created watchers will not be called as the watchers 577The callbacks of the created watchers will not be called as the watchers
522are destroyed before this cna happen (remember EV::check gets called 578are destroyed before this cna happen (remember EV::check gets called
523first). 579first).
526 582
527=back 583=back
528 584
529=head1 THREADS 585=head1 THREADS
530 586
531Threads are not supported by this in any way. Perl pseudo-threads is evil 587Threads are not supported by this module in any way. Perl pseudo-threads
532stuff and must die. 588is evil stuff and must die. As soon as Perl gains real threads I will work
589on thread support for it.
590
591=head1 FORK
592
593Most of the "improved" event delivering mechanisms of modern operating
594systems have quite a few problems with fork(2) (to put it bluntly: it is
595not supported and usually destructive). Libev makes it possible to work
596around this by having a function that recreates the kernel state after
597fork in the child.
598
599On non-win32 platforms, this module requires the pthread_atfork
600functionality to do this automatically for you. This function is quite
601buggy on most BSDs, though, so YMMV. The overhead for this is quite
602negligible, because everything the function currently does is set a flag
603that is checked only when the event loop gets used the next time, so when
604you do fork but not use EV, the overhead is minimal.
605
606On win32, there is no notion of fork so all this doesn't apply, of course.
533 607
534=cut 608=cut
535 609
536our $DIED = sub { 610our $DIED = sub {
537 warn "EV: error in callback (ignoring): $@"; 611 warn "EV: error in callback (ignoring): $@";
542 616
5431; 6171;
544 618
545=head1 SEE ALSO 619=head1 SEE ALSO
546 620
547 L<EV::DNS>, L<EV::AnyEvent>. 621 L<EV::DNS>.
548 622
549=head1 AUTHOR 623=head1 AUTHOR
550 624
551 Marc Lehmann <schmorp@schmorp.de> 625 Marc Lehmann <schmorp@schmorp.de>
552 http://home.schmorp.de/ 626 http://home.schmorp.de/

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