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Comparing cvsroot/EV/EV.pm (file contents):
Revision 1.61 by root, Thu Dec 6 03:13:07 2007 UTC vs.
Revision 1.71 by root, Mon Dec 17 07:24:12 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 = '1.86';
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 =
92=over 4 93=over 4
93 94
94=item $EV::DIED 95=item $EV::DIED
95 96
96Must contain a reference to a function that is called when a callback 97Must contain a reference to a function that is called when a callback
97throws an exception (with $@ containing thr error). The default prints an 98throws an exception (with $@ containing the error). The default prints an
98informative message and continues. 99informative message and continues.
99 100
100If this callback throws an exception it will be silently ignored. 101If this callback throws an exception it will be silently ignored.
101 102
102=item $time = EV::time 103=item $time = EV::time
159 160
160EV::once doesn't return anything: the watchers stay active till either 161EV::once doesn't return anything: the watchers stay active till either
161of them triggers, then they will be stopped and freed, and the callback 162of them triggers, then they will be stopped and freed, and the callback
162invoked. 163invoked.
163 164
165=item EV::feed_fd_event ($fd, $revents)
166
167Feed an event on a file descriptor into EV. EV will react to this call as
168if the readyness notifications specified by C<$revents> (a combination of
169C<EV::READ> and C<EV::WRITE>) happened on the file descriptor C<$fd>.
170
171=item EV::feed_signal_event ($signal)
172
173Feed a signal event into EV. EV will react to this call as if the signal
174specified by C<$signal> had occured.
175
164=back 176=back
177
165 178
166=head2 WATCHER OBJECTS 179=head2 WATCHER OBJECTS
167 180
168A watcher is an object that gets created to record your interest in some 181A 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 182event. For instance, if you want to wait for STDIN to become readable, you
180events. 193events.
181 194
182Each watcher type has its associated bit in revents, so you can use the 195Each 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 196same callback for multiple watchers. The event mask is named after the
184type, i..e. EV::child sets EV::CHILD, EV::prepare sets EV::PREPARE, 197type, 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 198EV::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 199(which can set both EV::READ and EV::WRITE bits), and EV::timer (which
187uses EV::TIMEOUT). 200uses EV::TIMEOUT).
188 201
189In the rare case where one wants to create a watcher but not start it at 202In 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 203the same time, each constructor has a variant with a trailing C<_ns> in
212 225
213=item $w->stop 226=item $w->stop
214 227
215Stop a watcher if it is active. Also clear any pending events (events that 228Stop 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), 229have been received but that didn't yet result in a callback invocation),
217regardless of wether the watcher was active or not. 230regardless of whether the watcher was active or not.
218 231
219=item $bool = $w->is_active 232=item $bool = $w->is_active
220 233
221Returns true if the watcher is active, false otherwise. 234Returns true if the watcher is active, false otherwise.
222 235
252The default priority of any newly-created watcher is 0. 265The default priority of any newly-created watcher is 0.
253 266
254Note that the priority semantics have not yet been fleshed out and are 267Note that the priority semantics have not yet been fleshed out and are
255subject to almost certain change. 268subject to almost certain change.
256 269
257=item $w->trigger ($revents) 270=item $w->invoke ($revents)
258 271
259Call the callback *now* with the given event mask. 272Call the callback *now* with the given event mask.
273
274=item $w->feed_event ($revents)
275
276Feed some events on this watcher into EV. EV will react to this call as if
277the watcher had received the given C<$revents> mask.
278
279=item $revents = $w->clear_pending
280
281If the watcher is pending, this function returns clears its pending status
282and returns its C<$revents> bitset (as if its callback was invoked). If the
283watcher isn't pending it does nothing and returns C<0>.
260 284
261=item $previous_state = $w->keepalive ($bool) 285=item $previous_state = $w->keepalive ($bool)
262 286
263Normally, C<EV::loop> will return when there are no active watchers 287Normally, 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 288(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. 301though your watcher is active, it won't keep C<EV::loop> from returning.
278 302
279The initial value for keepalive is true (enabled), and you cna change it 303The initial value for keepalive is true (enabled), and you cna change it
280any time. 304any time.
281 305
282Example: Register an IO watcher for some UDP socket but do not keep the 306Example: Register an I/O watcher for some UDP socket but do not keep the
283event loop from running just because of that watcher. 307event loop from running just because of that watcher.
284 308
285 my $udp_socket = ... 309 my $udp_socket = ...
286 my $udp_watcher = EV::io $udp_socket, EV::READ, sub { ... }; 310 my $udp_watcher = EV::io $udp_socket, EV::READ, sub { ... };
287 $udp_watcher->keepalive (0); 311 $udp_watcher->keepalive (0);
291 315
292=head2 WATCHER TYPES 316=head2 WATCHER TYPES
293 317
294Each of the following subsections describes a single watcher type. 318Each of the following subsections describes a single watcher type.
295 319
296=head3 IO WATCHERS - is this file descriptor readable or writable? 320=head3 I/O WATCHERS - is this file descriptor readable or writable?
297 321
298=over 4 322=over 4
299 323
300=item $w = EV::io $fileno_or_fh, $eventmask, $callback 324=item $w = EV::io $fileno_or_fh, $eventmask, $callback
301 325
470 494
471=item $w->again 495=item $w->again
472 496
473Simply stops and starts the watcher again. 497Simply stops and starts the watcher again.
474 498
499=item $time = $w->at
500
501Return the time that the watcher is expected to trigger next.
502
475=back 503=back
476 504
477 505
478=head3 SIGNAL WATCHERS - signal me when a signal gets signalled! 506=head3 SIGNAL WATCHERS - signal me when a signal gets signalled!
479 507
645 673
646=item $w = EV::idle $callback 674=item $w = EV::idle $callback
647 675
648=item $w = EV::idle_ns $callback 676=item $w = EV::idle_ns $callback
649 677
650Call the callback when there are no pending io, timer/periodic, signal or 678Call the callback when there are no other pending watchers of the same or
651child events, i.e. when the process is idle. 679higher priority (excluding check, prepare and other idle watchers of the
680same or lower priority, of course). They are called idle watchers because
681when the watcher is the highest priority pending event in the process, the
682process is considered to be idle at that priority.
683
684If you want a watcher that is only ever called when I<no> other events are
685outstanding you have to set the priority to C<EV::MINPRI>.
652 686
653The process will not block as long as any idle watchers are active, and 687The process will not block as long as any idle watchers are active, and
654they will be called repeatedly until stopped. 688they will be called repeatedly until stopped.
689
690For example, if you have idle watchers at priority C<0> and C<1>, and
691an I/O watcher at priority C<0>, then the idle watcher at priority C<1>
692and the I/O watcher will always run when ready. Only when the idle watcher
693at priority C<1> is stopped and the I/O watcher at priority C<0> is not
694pending with the C<0>-priority idle watcher be invoked.
655 695
656The C<idle_ns> variant doesn't start (activate) the newly created watcher. 696The C<idle_ns> variant doesn't start (activate) the newly created watcher.
657 697
658=back 698=back
659 699
700 or return; 740 or return;
701 741
702 # make the dispatcher handle any outstanding stuff 742 # make the dispatcher handle any outstanding stuff
703 ... not shown 743 ... not shown
704 744
705 # create an IO watcher for each and every socket 745 # create an I/O watcher for each and every socket
706 @snmp_watcher = ( 746 @snmp_watcher = (
707 (map { EV::io $_, EV::READ, sub { } } 747 (map { EV::io $_, EV::READ, sub { } }
708 keys %{ $dispatcher->{_descriptors} }), 748 keys %{ $dispatcher->{_descriptors} }),
709 749
710 EV::timer +($event->[Net::SNMP::Dispatcher::_ACTIVE] 750 EV::timer +($event->[Net::SNMP::Dispatcher::_ACTIVE]
802our $DIED = sub { 842our $DIED = sub {
803 warn "EV: error in callback (ignoring): $@"; 843 warn "EV: error in callback (ignoring): $@";
804}; 844};
805 845
806default_loop 846default_loop
807 or die 'EV: cannot initialise libev backend. bad $ENV{LIBEV_METHODS}?'; 847 or die 'EV: cannot initialise libev backend. bad $ENV{LIBEV_FLAGS}?';
808 848
8091; 8491;
810 850
811=head1 SEE ALSO 851=head1 SEE ALSO
812 852

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