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Revision 1.73 by root, Fri Dec 21 05:10:01 2007 UTC vs.
Revision 1.95 by root, Wed May 21 23:35:00 2008 UTC

35 warn "sigquit received\n"; 35 warn "sigquit received\n";
36 }; 36 };
37 37
38 # CHILD/PID STATUS CHANGES 38 # CHILD/PID STATUS CHANGES
39 39
40 my $w = EV::child 666, sub { 40 my $w = EV::child 666, 0, sub {
41 my ($w, $revents) = @_; 41 my ($w, $revents) = @_;
42 my $status = $w->rstatus; 42 my $status = $w->rstatus;
43 }; 43 };
44 44
45 # STAT CHANGES 45 # STAT CHANGES
56=head1 DESCRIPTION 56=head1 DESCRIPTION
57 57
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://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod>) for more
62watcher semantics or some discussion on the available backends, or how to 62subtle details on watcher semantics or some discussion on the available
63force a specific backend with C<LIBEV_FLAGS>, or just about in any case 63backends, or how to force a specific backend with C<LIBEV_FLAGS>, or just
64because it has much more detailed information. 64about in any case because it has much more detailed information.
65
66This module is very fast and scalable. It is actually so fast that you
67can use it through the L<AnyEvent> module, stay portable to other event
68loops (if you don't rely on any watcher types not available through it)
69and still be faster than with any other event loop currently supported in
70Perl.
65 71
66=cut 72=cut
67 73
68package EV; 74package EV;
69 75
70use strict; 76use strict;
71 77
72BEGIN { 78BEGIN {
73 our $VERSION = '2.0'; 79 our $VERSION = '3.41';
74 use XSLoader; 80 use XSLoader;
75 XSLoader::load "EV", $VERSION; 81 XSLoader::load "EV", $VERSION;
76} 82}
77 83
78@EV::IO::ISA = 84@EV::IO::ISA =
84@EV::Idle::ISA = 90@EV::Idle::ISA =
85@EV::Prepare::ISA = 91@EV::Prepare::ISA =
86@EV::Check::ISA = 92@EV::Check::ISA =
87@EV::Embed::ISA = 93@EV::Embed::ISA =
88@EV::Fork::ISA = 94@EV::Fork::ISA =
95@EV::Async::ISA =
89 "EV::Watcher"; 96 "EV::Watcher";
90 97
91@EV::Loop::Default::ISA = "EV::Loop"; 98@EV::Loop::Default::ISA = "EV::Loop";
92 99
93=head1 EVENT LOOPS 100=head1 EVENT LOOPS
102selecting a working backend (which for example rules out kqueue on most 109selecting a working backend (which for example rules out kqueue on most
103BSDs). Modules should, unless they have "special needs" always use the 110BSDs). Modules should, unless they have "special needs" always use the
104default loop as this is fastest (perl-wise), best supported by other 111default loop as this is fastest (perl-wise), best supported by other
105modules (e.g. AnyEvent or Coro) and most portable event loop. 112modules (e.g. AnyEvent or Coro) and most portable event loop.
106 113
107For specific programs you cna create additional event loops dynamically. 114For specific programs you can create additional event loops dynamically.
108 115
109=over 4 116=over 4
110 117
111=item $loop = new EV::loop [$flags] 118=item $loop = new EV::loop [$flags]
112 119
126Must be called after a fork in the child, before entering or continuing 133Must be called after a fork in the child, before entering or continuing
127the event loop. An alternative is to use C<EV::FLAG_FORKCHECK> which calls 134the event loop. An alternative is to use C<EV::FLAG_FORKCHECK> which calls
128this fucntion automatically, at some performance loss (refer to the libev 135this fucntion automatically, at some performance loss (refer to the libev
129documentation). 136documentation).
130 137
138=item $loop = EV::default_loop [$flags]
139
140Return the default loop (which is a singleton object).
141
131=back 142=back
132 143
133 144
134=head1 BASIC INTERFACE 145=head1 BASIC INTERFACE
135 146
140Must contain a reference to a function that is called when a callback 151Must contain a reference to a function that is called when a callback
141throws an exception (with $@ containing the error). The default prints an 152throws an exception (with $@ containing the error). The default prints an
142informative message and continues. 153informative message and continues.
143 154
144If this callback throws an exception it will be silently ignored. 155If this callback throws an exception it will be silently ignored.
156
157=item $flags = EV::supported_backends
158
159=item $flags = EV::recommended_backends
160
161=item $flags = EV::embeddable_backends
162
163Returns the set (see C<EV::BACKEND_*> flags) of backends supported by this
164instance of EV, the set of recommended backends (supposed to be good) for
165this platform and the set of embeddable backends (see EMBED WATCHERS).
166
167=item EV::sleep $seconds
168
169Block the process for the given number of (fractional) seconds.
145 170
146=item $time = EV::time 171=item $time = EV::time
147 172
148Returns the current time in (fractional) seconds since the epoch. 173Returns the current time in (fractional) seconds since the epoch.
149 174
208If timeout is C<undef> or negative, then there will be no 233If timeout is C<undef> or negative, then there will be no
209timeout. Otherwise a EV::timer with this value will be started. 234timeout. Otherwise a EV::timer with this value will be started.
210 235
211When an error occurs or either the timeout or I/O watcher triggers, then 236When an error occurs or either the timeout or I/O watcher triggers, then
212the callback will be called with the received event set (in general 237the callback will be called with the received event set (in general
213you can expect it to be a combination of C<EV:ERROR>, C<EV::READ>, 238you can expect it to be a combination of C<EV::ERROR>, C<EV::READ>,
214C<EV::WRITE> and C<EV::TIMEOUT>). 239C<EV::WRITE> and C<EV::TIMEOUT>).
215 240
216EV::once doesn't return anything: the watchers stay active till either 241EV::once doesn't return anything: the watchers stay active till either
217of them triggers, then they will be stopped and freed, and the callback 242of them triggers, then they will be stopped and freed, and the callback
218invoked. 243invoked.
228=item EV::feed_signal_event ($signal) 253=item EV::feed_signal_event ($signal)
229 254
230Feed a signal event into EV. EV will react to this call as if the signal 255Feed a signal event into EV. EV will react to this call as if the signal
231specified by C<$signal> had occured. 256specified by C<$signal> had occured.
232 257
258=item EV::set_io_collect_interval $time
259
260=item $loop->set_io_collect_interval ($time)
261
262=item EV::set_timeout_collect_interval $time
263
264=item $loop->set_timeout_collect_interval ($time)
265
266These advanced functions set the minimum block interval when polling for I/O events and the minimum
267wait interval for timer events. See the libev documentation at
268L<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#FUNCTIONS_CONTROLLING_THE_EVENT_LOOP> for
269a more detailed discussion.
270
233=back 271=back
234 272
235 273
236=head1 WATCHER OBJECTS 274=head1 WATCHER OBJECTS
237 275
239event. For instance, if you want to wait for STDIN to become readable, you 277event. For instance, if you want to wait for STDIN to become readable, you
240would create an EV::io watcher for that: 278would create an EV::io watcher for that:
241 279
242 my $watcher = EV::io *STDIN, EV::READ, sub { 280 my $watcher = EV::io *STDIN, EV::READ, sub {
243 my ($watcher, $revents) = @_; 281 my ($watcher, $revents) = @_;
244 warn "yeah, STDIN should not be readable without blocking!\n" 282 warn "yeah, STDIN should now be readable without blocking!\n"
245 }; 283 };
246 284
247All watchers can be active (waiting for events) or inactive (paused). Only 285All watchers can be active (waiting for events) or inactive (paused). Only
248active watchers will have their callbacks invoked. All callbacks will be 286active watchers will have their callbacks invoked. All callbacks will be
249called with at least two arguments: the watcher and a bitmask of received 287called with at least two arguments: the watcher and a bitmask of received
333Feed some events on this watcher into EV. EV will react to this call as if 371Feed some events on this watcher into EV. EV will react to this call as if
334the watcher had received the given C<$revents> mask. 372the watcher had received the given C<$revents> mask.
335 373
336=item $revents = $w->clear_pending 374=item $revents = $w->clear_pending
337 375
338If the watcher is pending, this function returns clears its pending status 376If the watcher is pending, this function clears its pending status and
339and returns its C<$revents> bitset (as if its callback was invoked). If the 377returns its C<$revents> bitset (as if its callback was invoked). If the
340watcher isn't pending it does nothing and returns C<0>. 378watcher isn't pending it does nothing and returns C<0>.
341 379
342=item $previous_state = $w->keepalive ($bool) 380=item $previous_state = $w->keepalive ($bool)
343 381
344Normally, C<EV::loop> will return when there are no active watchers 382Normally, C<EV::loop> will return when there are no active watchers
345(which is a "deadlock" because no progress can be made anymore). This is 383(which is a "deadlock" because no progress can be made anymore). This is
346convinient because it allows you to start your watchers (and your jobs), 384convinient because it allows you to start your watchers (and your jobs),
347call C<EV::loop> once and when it returns you know that all your jobs are 385call C<EV::loop> once and when it returns you know that all your jobs are
348finished (or they forgot to register some watchers for their task :). 386finished (or they forgot to register some watchers for their task :).
349 387
350Sometimes, however, this gets in your way, for example when you the module 388Sometimes, however, this gets in your way, for example when the module
351that calls C<EV::loop> (usually the main program) is not the same module 389that calls C<EV::loop> (usually the main program) is not the same module
352as a long-living watcher (for example a DNS client module written by 390as a long-living watcher (for example a DNS client module written by
353somebody else even). Then you might want any outstanding requests to be 391somebody else even). Then you might want any outstanding requests to be
354handled, but you would not want to keep C<EV::loop> from returning just 392handled, but you would not want to keep C<EV::loop> from returning just
355because you happen to have this long-running UDP port watcher. 393because you happen to have this long-running UDP port watcher.
363Example: Register an I/O watcher for some UDP socket but do not keep the 401Example: Register an I/O watcher for some UDP socket but do not keep the
364event loop from running just because of that watcher. 402event loop from running just because of that watcher.
365 403
366 my $udp_socket = ... 404 my $udp_socket = ...
367 my $udp_watcher = EV::io $udp_socket, EV::READ, sub { ... }; 405 my $udp_watcher = EV::io $udp_socket, EV::READ, sub { ... };
368 $udp_watcher->keepalive (0); 406 $1000udp_watcher->keepalive (0);
407
408=item $loop = $w->loop
409
410Return the loop that this watcher is attached to.
369 411
370=back 412=back
371 413
372 414
373=head1 WATCHER TYPES 415=head1 WATCHER TYPES
380 422
381=item $w = EV::io $fileno_or_fh, $eventmask, $callback 423=item $w = EV::io $fileno_or_fh, $eventmask, $callback
382 424
383=item $w = EV::io_ns $fileno_or_fh, $eventmask, $callback 425=item $w = EV::io_ns $fileno_or_fh, $eventmask, $callback
384 426
385=item $w = $loop->io 8$fileno_or_fh, $eventmask, $callback) 427=item $w = $loop->io ($fileno_or_fh, $eventmask, $callback)
386 428
387=item $w = $loop->io_ns ($fileno_or_fh, $eventmask, $callback) 429=item $w = $loop->io_ns ($fileno_or_fh, $eventmask, $callback)
388 430
389As long as the returned watcher object is alive, call the C<$callback> 431As long as the returned watcher object is alive, call the C<$callback>
390when at least one of events specified in C<$eventmask> occurs. 432when at least one of events specified in C<$eventmask> occurs.
498This time simply fires at the wallclock time C<$at> and doesn't repeat. It 540This time simply fires at the wallclock time C<$at> and doesn't repeat. It
499will not adjust when a time jump occurs, that is, if it is to be run 541will not adjust when a time jump occurs, that is, if it is to be run
500at January 1st 2011 then it will run when the system time reaches or 542at January 1st 2011 then it will run when the system time reaches or
501surpasses this time. 543surpasses this time.
502 544
503=item * non-repeating interval timer ($interval > 0, $reschedule_cb = 0) 545=item * repeating interval timer ($interval > 0, $reschedule_cb = 0)
504 546
505In this mode the watcher will always be scheduled to time out at the 547In this mode the watcher will always be scheduled to time out at the
506next C<$at + N * $interval> time (for some integer N) and then repeat, 548next C<$at + N * $interval> time (for some integer N) and then repeat,
507regardless of any time jumps. 549regardless of any time jumps.
508 550
526time the periodic watcher gets scheduled, the reschedule callback 568time the periodic watcher gets scheduled, the reschedule callback
527($reschedule_cb) will be called with the watcher as first, and the current 569($reschedule_cb) will be called with the watcher as first, and the current
528time as second argument. 570time as second argument.
529 571
530I<This callback MUST NOT stop or destroy this or any other periodic 572I<This callback MUST NOT stop or destroy this or any other periodic
531watcher, ever>. If you need to stop it, return 1e30 and stop it 573watcher, ever, and MUST NOT call any event loop functions or methods>. If
532afterwards. 574you need to stop it, return 1e30 and stop it afterwards. You may create
575and start a C<EV::prepare> watcher for this task.
533 576
534It must return the next time to trigger, based on the passed time value 577It must return the next time to trigger, based on the passed time value
535(that is, the lowest time value larger than to the second argument). It 578(that is, the lowest time value larger than or equal to to the second
536will usually be called just before the callback will be triggered, but 579argument). It will usually be called just before the callback will be
537might be called at other times, too. 580triggered, but might be called at other times, too.
538 581
539This can be used to create very complex timers, such as a timer that 582This can be used to create very complex timers, such as a timer that
540triggers on each midnight, local time (actually 24 hours after the last 583triggers on each midnight, local time (actually 24 hours after the last
541midnight, to keep the example simple. If you know a way to do it correctly 584midnight, to keep the example simple. If you know a way to do it correctly
542in about the same space (without requiring elaborate modules), drop me a 585in about the same space (without requiring elaborate modules), drop me a
609 652
610=head3 CHILD WATCHERS - watch out for process status changes 653=head3 CHILD WATCHERS - watch out for process status changes
611 654
612=over 4 655=over 4
613 656
614=item $w = EV::child $pid, $callback 657=item $w = EV::child $pid, $trace, $callback
615 658
616=item $w = EV::child_ns $pid, $callback 659=item $w = EV::child_ns $pid, $trace, $callback
617 660
618=item $w = $loop->child ($pid, $callback) 661=item $w = $loop->child ($pid, $trace, $callback)
619 662
620=item $w = $loop->child_ns ($pid, $callback) 663=item $w = $loop->child_ns ($pid, $trace, $callback)
621 664
622Call the callback when a status change for pid C<$pid> (or any pid if 665Call the callback when a status change for pid C<$pid> (or any pid
623C<$pid> is 0) has been received. More precisely: when the process receives 666if C<$pid> is 0) has been received (a status change happens when the
667process terminates or is killed, or, when trace is true, additionally when
668it is stopped or continued). More precisely: when the process receives
624a C<SIGCHLD>, EV will fetch the outstanding exit/wait status for all 669a C<SIGCHLD>, EV will fetch the outstanding exit/wait status for all
625changed/zombie children and call the callback. 670changed/zombie children and call the callback.
626 671
627It is valid (and fully supported) to install a child watcher after a child 672It is valid (and fully supported) to install a child watcher after a child
628has exited but before the event loop has started its next iteration (for 673has exited but before the event loop has started its next iteration (for
635You can have as many pid watchers per pid as you want, they will all be 680You can have as many pid watchers per pid as you want, they will all be
636called. 681called.
637 682
638The C<child_ns> variant doesn't start (activate) the newly created watcher. 683The C<child_ns> variant doesn't start (activate) the newly created watcher.
639 684
640=item $w->set ($pid) 685=item $w->set ($pid, $trace)
641 686
642Reconfigures the watcher, see the constructor above for details. Can be called at 687Reconfigures the watcher, see the constructor above for details. Can be called at
643any time. 688any time.
644 689
645=item $current_pid = $w->pid 690=item $current_pid = $w->pid
646
647=item $old_pid = $w->pid ($new_pid)
648 691
649Returns the previously set process id and optionally set a new one. 692Returns the previously set process id and optionally set a new one.
650 693
651=item $exit_status = $w->rstatus 694=item $exit_status = $w->rstatus
652 695
787 830
788=item $w = EV::prepare_ns $callback 831=item $w = EV::prepare_ns $callback
789 832
790=item $w = $loop->prepare ($callback) 833=item $w = $loop->prepare ($callback)
791 834
792=item $w = $loop->prepare_ns 8$callback) 835=item $w = $loop->prepare_ns ($callback)
793 836
794Call the callback just before the process would block. You can still 837Call the callback just before the process would block. You can still
795create/modify any watchers at this point. 838create/modify any watchers at this point.
796 839
797See the EV::check watcher, below, for explanations and an example. 840See the EV::check watcher, below, for explanations and an example.
886The C<fork_ns> variant doesn't start (activate) the newly created watcher. 929The C<fork_ns> variant doesn't start (activate) the newly created watcher.
887 930
888=back 931=back
889 932
890 933
934=head3 EMBED WATCHERS - when one backend isn't enough...
935
936This is a rather advanced watcher type that lets you embed one event loop
937into another (currently only IO events are supported in the embedded
938loop, other types of watchers might be handled in a delayed or incorrect
939fashion and must not be used).
940
941See the libev documentation at
942L<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#code_ev_embed_code_when_one_backend_>
943for more details.
944
945In short, this watcher is most useful on BSD systems without working
946kqueue to still be able to handle a large number of sockets:
947
948 my $socket_loop;
949
950 # check wether we use SELECT or POLL _and_ KQUEUE is supported
951 if (
952 (EV::backend & (EV::BACKEND_POLL | EV::BACKEND_SELECT))
953 && (EV::supported_backends & EV::embeddable_backends & EV::BACKEND_KQUEUE)
954 ) {
955 # use kqueue for sockets
956 $socket_loop = new EV::Loop EV::BACKEND_KQUEUE | EV::FLAG_NOENV;
957 }
958
959 # use the default loop otherwise
960 $socket_loop ||= EV::default_loop;
961
962=over 4
963
964=item $w = EV::embed $otherloop, $callback
965
966=item $w = EV::embed_ns $otherloop, $callback
967
968=item $w = $loop->embed ($otherloop, $callback)
969
970=item $w = $loop->embed_ns ($otherloop, $callback)
971
972Call the callback when the embedded event loop (C<$otherloop>) has any
973I/O activity. The C<$callback> should alwas be specified as C<undef> in
974this version of EV, which means the embedded event loop will be managed
975automatically.
976
977The C<embed_ns> variant doesn't start (activate) the newly created watcher.
978
979=back
980
981=head3 ASYNC WATCHERS - how to wake up another event loop
982
983Async watchers are provided by EV, but have little use in perl directly, as perl
984neither supports threads nor direct access to signal handlers or other
985contexts where they could be of value.
986
987It is, however, possible to use them from the XS level.
988
989Please see the libev documentation for further details.
990
991=over 4
992
993=item $w = EV::async $callback
994
995=item $w = EV::async_ns $callback
996
997=item $w->send
998
999=item $bool = $w->async_pending
1000
1001=back
1002
1003
891=head1 PERL SIGNALS 1004=head1 PERL SIGNALS
892 1005
893While Perl signal handling (C<%SIG>) is not affected by EV, the behaviour 1006While Perl signal handling (C<%SIG>) is not affected by EV, the behaviour
894with EV is as the same as any other C library: Perl-signals will only be 1007with EV is as the same as any other C library: Perl-signals will only be
895handled when Perl runs, which means your signal handler might be invoked 1008handled when Perl runs, which means your signal handler might be invoked
902to be called on every event loop iteration by installing a C<EV::check> 1015to be called on every event loop iteration by installing a C<EV::check>
903watcher: 1016watcher:
904 1017
905 my $async_check = EV::check sub { }; 1018 my $async_check = EV::check sub { };
906 1019
907This ensures that perl shortly gets into control for a short time, and 1020This ensures that perl gets into control for a short time to handle any
908also ensures slower overall operation. 1021pending signals, and also ensures (slightly) slower overall operation.
909 1022
910=head1 THREADS 1023=head1 THREADS
911 1024
912Threads are not supported by this module in any way. Perl pseudo-threads 1025Threads are not supported by this module in any way. Perl pseudo-threads
913is evil stuff and must die. As soon as Perl gains real threads I will work 1026is evil stuff and must die. As soon as Perl gains real threads I will work
943 1056
944=head1 SEE ALSO 1057=head1 SEE ALSO
945 1058
946L<EV::ADNS> (asynchronous DNS), L<Glib::EV> (makes Glib/Gtk2 use EV as 1059L<EV::ADNS> (asynchronous DNS), L<Glib::EV> (makes Glib/Gtk2 use EV as
947event loop), L<EV::Glib> (embed Glib into EV), L<Coro::EV> (efficient 1060event loop), L<EV::Glib> (embed Glib into EV), L<Coro::EV> (efficient
948coroutines with EV), L<Net::SNMP::EV> (asynchronous SNMP). 1061coroutines with EV), L<Net::SNMP::EV> (asynchronous SNMP), L<AnyEvent> for
1062event-loop agnostic and portable event driven programming.
949 1063
950=head1 AUTHOR 1064=head1 AUTHOR
951 1065
952 Marc Lehmann <schmorp@schmorp.de> 1066 Marc Lehmann <schmorp@schmorp.de>
953 http://home.schmorp.de/ 1067 http://home.schmorp.de/

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