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Comparing EV/EV.pm (file contents):
Revision 1.61 by root, Thu Dec 6 03:13:07 2007 UTC vs.
Revision 1.72 by root, Thu Dec 20 07:12:57 2007 UTC

58This module provides an interface to libev 58This module provides an interface to libev
59(L<http://software.schmorp.de/pkg/libev.html>). While the documentation 59(L<http://software.schmorp.de/pkg/libev.html>). While the documentation
60below is comprehensive, one might also consult the documentation of libev 60below is comprehensive, one might also consult the documentation of libev
61itself (L<http://cvs.schmorp.de/libev/ev.html>) for more subtle details on 61itself (L<http://cvs.schmorp.de/libev/ev.html>) for more subtle details on
62watcher semantics or some discussion on the available backends, or how to 62watcher semantics or some discussion on the available backends, or how to
63force a specific backend with C<LIBEV_FLAGS>. 63force a specific backend with C<LIBEV_FLAGS>, or just about in any case
64because it has much more detailed information.
64 65
65=cut 66=cut
66 67
67package EV; 68package EV;
68 69
69use strict; 70use strict;
70 71
71BEGIN { 72BEGIN {
72 our $VERSION = '1.6'; 73 our $VERSION = '2.0';
73 use XSLoader; 74 use XSLoader;
74 XSLoader::load "EV", $VERSION; 75 XSLoader::load "EV", $VERSION;
75} 76}
76 77
77@EV::IO::ISA = 78@EV::IO::ISA =
85@EV::Check::ISA = 86@EV::Check::ISA =
86@EV::Embed::ISA = 87@EV::Embed::ISA =
87@EV::Fork::ISA = 88@EV::Fork::ISA =
88 "EV::Watcher"; 89 "EV::Watcher";
89 90
91@EV::Loop::Default::ISA = "EV::Loop";
92
90=head1 BASIC INTERFACE 93=head1 BASIC INTERFACE
91 94
92=over 4 95=over 4
93 96
94=item $EV::DIED 97=item $EV::DIED
95 98
96Must contain a reference to a function that is called when a callback 99Must contain a reference to a function that is called when a callback
97throws an exception (with $@ containing thr error). The default prints an 100throws an exception (with $@ containing the error). The default prints an
98informative message and continues. 101informative message and continues.
99 102
100If this callback throws an exception it will be silently ignored. 103If this callback throws an exception it will be silently ignored.
101 104
102=item $time = EV::time 105=item $time = EV::time
159 162
160EV::once doesn't return anything: the watchers stay active till either 163EV::once doesn't return anything: the watchers stay active till either
161of them triggers, then they will be stopped and freed, and the callback 164of them triggers, then they will be stopped and freed, and the callback
162invoked. 165invoked.
163 166
167=item EV::feed_fd_event ($fd, $revents)
168
169Feed an event on a file descriptor into EV. EV will react to this call as
170if the readyness notifications specified by C<$revents> (a combination of
171C<EV::READ> and C<EV::WRITE>) happened on the file descriptor C<$fd>.
172
173=item EV::feed_signal_event ($signal)
174
175Feed a signal event into EV. EV will react to this call as if the signal
176specified by C<$signal> had occured.
177
164=back 178=back
179
165 180
166=head2 WATCHER OBJECTS 181=head2 WATCHER OBJECTS
167 182
168A watcher is an object that gets created to record your interest in some 183A watcher is an object that gets created to record your interest in some
169event. For instance, if you want to wait for STDIN to become readable, you 184event. For instance, if you want to wait for STDIN to become readable, you
180events. 195events.
181 196
182Each watcher type has its associated bit in revents, so you can use the 197Each watcher type has its associated bit in revents, so you can use the
183same callback for multiple watchers. The event mask is named after the 198same callback for multiple watchers. The event mask is named after the
184type, i..e. EV::child sets EV::CHILD, EV::prepare sets EV::PREPARE, 199type, i..e. EV::child sets EV::CHILD, EV::prepare sets EV::PREPARE,
185EV::periodic sets EV::PERIODIC and so on, with the exception of IO events 200EV::periodic sets EV::PERIODIC and so on, with the exception of I/O events
186(which can set both EV::READ and EV::WRITE bits), and EV::timer (which 201(which can set both EV::READ and EV::WRITE bits), and EV::timer (which
187uses EV::TIMEOUT). 202uses EV::TIMEOUT).
188 203
189In the rare case where one wants to create a watcher but not start it at 204In the rare case where one wants to create a watcher but not start it at
190the same time, each constructor has a variant with a trailing C<_ns> in 205the same time, each constructor has a variant with a trailing C<_ns> in
212 227
213=item $w->stop 228=item $w->stop
214 229
215Stop a watcher if it is active. Also clear any pending events (events that 230Stop a watcher if it is active. Also clear any pending events (events that
216have been received but that didn't yet result in a callback invocation), 231have been received but that didn't yet result in a callback invocation),
217regardless of wether the watcher was active or not. 232regardless of whether the watcher was active or not.
218 233
219=item $bool = $w->is_active 234=item $bool = $w->is_active
220 235
221Returns true if the watcher is active, false otherwise. 236Returns true if the watcher is active, false otherwise.
222 237
252The default priority of any newly-created watcher is 0. 267The default priority of any newly-created watcher is 0.
253 268
254Note that the priority semantics have not yet been fleshed out and are 269Note that the priority semantics have not yet been fleshed out and are
255subject to almost certain change. 270subject to almost certain change.
256 271
257=item $w->trigger ($revents) 272=item $w->invoke ($revents)
258 273
259Call the callback *now* with the given event mask. 274Call the callback *now* with the given event mask.
275
276=item $w->feed_event ($revents)
277
278Feed some events on this watcher into EV. EV will react to this call as if
279the watcher had received the given C<$revents> mask.
280
281=item $revents = $w->clear_pending
282
283If the watcher is pending, this function returns clears its pending status
284and returns its C<$revents> bitset (as if its callback was invoked). If the
285watcher isn't pending it does nothing and returns C<0>.
260 286
261=item $previous_state = $w->keepalive ($bool) 287=item $previous_state = $w->keepalive ($bool)
262 288
263Normally, C<EV::loop> will return when there are no active watchers 289Normally, C<EV::loop> will return when there are no active watchers
264(which is a "deadlock" because no progress can be made anymore). This is 290(which is a "deadlock" because no progress can be made anymore). This is
277though your watcher is active, it won't keep C<EV::loop> from returning. 303though your watcher is active, it won't keep C<EV::loop> from returning.
278 304
279The initial value for keepalive is true (enabled), and you cna change it 305The initial value for keepalive is true (enabled), and you cna change it
280any time. 306any time.
281 307
282Example: Register an IO watcher for some UDP socket but do not keep the 308Example: Register an I/O watcher for some UDP socket but do not keep the
283event loop from running just because of that watcher. 309event loop from running just because of that watcher.
284 310
285 my $udp_socket = ... 311 my $udp_socket = ...
286 my $udp_watcher = EV::io $udp_socket, EV::READ, sub { ... }; 312 my $udp_watcher = EV::io $udp_socket, EV::READ, sub { ... };
287 $udp_watcher->keepalive (0); 313 $udp_watcher->keepalive (0);
291 317
292=head2 WATCHER TYPES 318=head2 WATCHER TYPES
293 319
294Each of the following subsections describes a single watcher type. 320Each of the following subsections describes a single watcher type.
295 321
296=head3 IO WATCHERS - is this file descriptor readable or writable? 322=head3 I/O WATCHERS - is this file descriptor readable or writable?
297 323
298=over 4 324=over 4
299 325
300=item $w = EV::io $fileno_or_fh, $eventmask, $callback 326=item $w = EV::io $fileno_or_fh, $eventmask, $callback
301 327
470 496
471=item $w->again 497=item $w->again
472 498
473Simply stops and starts the watcher again. 499Simply stops and starts the watcher again.
474 500
501=item $time = $w->at
502
503Return the time that the watcher is expected to trigger next.
504
475=back 505=back
476 506
477 507
478=head3 SIGNAL WATCHERS - signal me when a signal gets signalled! 508=head3 SIGNAL WATCHERS - signal me when a signal gets signalled!
479 509
645 675
646=item $w = EV::idle $callback 676=item $w = EV::idle $callback
647 677
648=item $w = EV::idle_ns $callback 678=item $w = EV::idle_ns $callback
649 679
650Call the callback when there are no pending io, timer/periodic, signal or 680Call the callback when there are no other pending watchers of the same or
651child events, i.e. when the process is idle. 681higher priority (excluding check, prepare and other idle watchers of the
682same or lower priority, of course). They are called idle watchers because
683when the watcher is the highest priority pending event in the process, the
684process is considered to be idle at that priority.
685
686If you want a watcher that is only ever called when I<no> other events are
687outstanding you have to set the priority to C<EV::MINPRI>.
652 688
653The process will not block as long as any idle watchers are active, and 689The process will not block as long as any idle watchers are active, and
654they will be called repeatedly until stopped. 690they will be called repeatedly until stopped.
691
692For example, if you have idle watchers at priority C<0> and C<1>, and
693an I/O watcher at priority C<0>, then the idle watcher at priority C<1>
694and the I/O watcher will always run when ready. Only when the idle watcher
695at priority C<1> is stopped and the I/O watcher at priority C<0> is not
696pending with the C<0>-priority idle watcher be invoked.
655 697
656The C<idle_ns> variant doesn't start (activate) the newly created watcher. 698The C<idle_ns> variant doesn't start (activate) the newly created watcher.
657 699
658=back 700=back
659 701
700 or return; 742 or return;
701 743
702 # make the dispatcher handle any outstanding stuff 744 # make the dispatcher handle any outstanding stuff
703 ... not shown 745 ... not shown
704 746
705 # create an IO watcher for each and every socket 747 # create an I/O watcher for each and every socket
706 @snmp_watcher = ( 748 @snmp_watcher = (
707 (map { EV::io $_, EV::READ, sub { } } 749 (map { EV::io $_, EV::READ, sub { } }
708 keys %{ $dispatcher->{_descriptors} }), 750 keys %{ $dispatcher->{_descriptors} }),
709 751
710 EV::timer +($event->[Net::SNMP::Dispatcher::_ACTIVE] 752 EV::timer +($event->[Net::SNMP::Dispatcher::_ACTIVE]
802our $DIED = sub { 844our $DIED = sub {
803 warn "EV: error in callback (ignoring): $@"; 845 warn "EV: error in callback (ignoring): $@";
804}; 846};
805 847
806default_loop 848default_loop
807 or die 'EV: cannot initialise libev backend. bad $ENV{LIBEV_METHODS}?'; 849 or die 'EV: cannot initialise libev backend. bad $ENV{LIBEV_FLAGS}?';
808 850
8091; 8511;
810 852
811=head1 SEE ALSO 853=head1 SEE ALSO
812 854

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