ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/EV/EV.pm
(Generate patch)

Comparing EV/EV.pm (file contents):
Revision 1.82 by root, Fri Jan 25 15:45:08 2008 UTC vs.
Revision 1.114 by root, Wed Apr 15 19:35:53 2009 UTC

… …
2 2
3EV - perl interface to libev, a high performance full-featured event loop 3EV - perl interface to libev, a high performance full-featured event loop
4 4
5=head1 SYNOPSIS 5=head1 SYNOPSIS
6 6
7 use EV; 7 use EV;
8
9 # TIMERS
10
11 my $w = EV::timer 2, 0, sub {
12 warn "is called after 2s";
13 };
14
15 my $w = EV::timer 2, 2, sub {
16 warn "is called roughly every 2s (repeat = 2)";
17 };
18
19 undef $w; # destroy event watcher again
20
21 my $w = EV::periodic 0, 60, 0, sub {
22 warn "is called every minute, on the minute, exactly";
23 };
24
25 # IO
26
27 my $w = EV::io *STDIN, EV::READ, sub {
28 my ($w, $revents) = @_; # all callbacks receive the watcher and event mask
29 warn "stdin is readable, you entered: ", <STDIN>;
30 };
31
32 # SIGNALS
33
34 my $w = EV::signal 'QUIT', sub {
35 warn "sigquit received\n";
36 };
37
38 # CHILD/PID STATUS CHANGES
8 39
9 # TIMERS 40 my $w = EV::child 666, 0, sub {
41 my ($w, $revents) = @_;
42 my $status = $w->rstatus;
43 };
10 44
11 my $w = EV::timer 2, 0, sub {
12 warn "is called after 2s";
13 };
14
15 my $w = EV::timer 2, 2, sub {
16 warn "is called roughly every 2s (repeat = 2)";
17 };
18
19 undef $w; # destroy event watcher again
20
21 my $w = EV::periodic 0, 60, 0, sub {
22 warn "is called every minute, on the minute, exactly";
23 };
24
25 # IO
26
27 my $w = EV::io *STDIN, EV::READ, sub {
28 my ($w, $revents) = @_; # all callbacks receive the watcher and event mask
29 warn "stdin is readable, you entered: ", <STDIN>;
30 };
31
32 # SIGNALS
33
34 my $w = EV::signal 'QUIT', sub {
35 warn "sigquit received\n";
36 };
37
38 # CHILD/PID STATUS CHANGES
39
40 my $w = EV::child 666, 0, sub {
41 my ($w, $revents) = @_;
42 my $status = $w->rstatus;
43 };
44
45 # STAT CHANGES 45 # STAT CHANGES
46 my $w = EV::stat "/etc/passwd", 10, sub { 46 my $w = EV::stat "/etc/passwd", 10, sub {
47 my ($w, $revents) = @_; 47 my ($w, $revents) = @_;
48 warn $w->path, " has changed somehow.\n"; 48 warn $w->path, " has changed somehow.\n";
49 }; 49 };
50 50
51 # MAINLOOP 51 # MAINLOOP
52 EV::loop; # loop until EV::unloop is called or all watchers stop 52 EV::loop; # loop until EV::unloop is called or all watchers stop
53 EV::loop EV::LOOP_ONESHOT; # block until at least one event could be handled 53 EV::loop EV::LOOP_ONESHOT; # block until at least one event could be handled
54 EV::loop EV::LOOP_NONBLOCK; # try to handle same events, but do not block 54 EV::loop EV::LOOP_NONBLOCK; # try to handle same events, but do not block
55 55
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
61itself (L<http://cvs.schmorp.de/libev/ev.html>) for more subtle details on 61libev itself (L<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod> or
62watcher semantics or some discussion on the available backends, or how to 62F<perldoc EV::libev>) for more subtle details on watcher semantics or some
63force a specific backend with C<LIBEV_FLAGS>, or just about in any case 63discussion on the available backends, or how to force a specific backend
64because it has much more detailed information. 64with C<LIBEV_FLAGS>, or just about in any case because it has much more
65detailed information.
66
67This module is very fast and scalable. It is actually so fast that you
68can use it through the L<AnyEvent> module, stay portable to other event
69loops (if you don't rely on any watcher types not available through it)
70and still be faster than with any other event loop currently supported in
71Perl.
72
73=head2 MODULE EXPORTS
74
75This module does not export any symbols.
65 76
66=cut 77=cut
67 78
68package EV; 79package EV;
69 80
81no warnings;
70use strict; 82use strict;
71 83
72BEGIN { 84BEGIN {
73 our $VERSION = '2.01'; 85 our $VERSION = '3.53';
74 use XSLoader; 86 use XSLoader;
75 XSLoader::load "EV", $VERSION; 87 XSLoader::load "EV", $VERSION;
76} 88}
77 89
78@EV::IO::ISA = 90@EV::IO::ISA =
… …
84@EV::Idle::ISA = 96@EV::Idle::ISA =
85@EV::Prepare::ISA = 97@EV::Prepare::ISA =
86@EV::Check::ISA = 98@EV::Check::ISA =
87@EV::Embed::ISA = 99@EV::Embed::ISA =
88@EV::Fork::ISA = 100@EV::Fork::ISA =
101@EV::Async::ISA =
89 "EV::Watcher"; 102 "EV::Watcher";
90 103
91@EV::Loop::Default::ISA = "EV::Loop"; 104@EV::Loop::Default::ISA = "EV::Loop";
92 105
93=head1 EVENT LOOPS 106=head1 EVENT LOOPS
… …
104default loop as this is fastest (perl-wise), best supported by other 117default loop as this is fastest (perl-wise), best supported by other
105modules (e.g. AnyEvent or Coro) and most portable event loop. 118modules (e.g. AnyEvent or Coro) and most portable event loop.
106 119
107For specific programs you can create additional event loops dynamically. 120For specific programs you can create additional event loops dynamically.
108 121
109=over 4 122If you want to take advantage of kqueue (which often works properly for
123sockets only) even though the default loop doesn't enable it, you can
124I<embed> a kqueue loop into the default loop: running the default loop
125will then also service the kqueue loop to some extent. See the example in
126the section about embed watchers for an example on how to achieve that.
110 127
128=over 4
129
111=item $loop = new EV::loop [$flags] 130=item $loop = new EV::Loop [$flags]
112 131
113Create a new event loop as per the specified flags. Please refer to the 132Create a new event loop as per the specified flags. Please refer to
114C<ev_loop_new ()> function description in the libev documentation 133the C<ev_loop_new ()> function description in the libev documentation
115(L<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#GLOBAL_FUNCTIONS>) 134(L<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#GLOBAL_FUNCTIONS>,
116for more info. 135or locally-installed as F<EV::libev> manpage) for more info.
117 136
118The loop will automatically be destroyed when it is no longer referenced 137The loop will automatically be destroyed when it is no longer referenced
119by any watcher and the loop object goes out of scope. 138by any watcher and the loop object goes out of scope.
120 139
121Using C<EV::FLAG_FORKCHECK> is recommended, as only the default event loop 140If you are not embedding the loop, then Using C<EV::FLAG_FORKCHECK>
122is protected by this module. 141is recommended, as only the default event loop is protected by this
142module. If you I<are> embedding this loop in the default loop, this is not
143necessary, as C<EV::embed> automatically does the right thing on fork.
123 144
124=item $loop->loop_fork 145=item $loop->loop_fork
125 146
126Must be called after a fork in the child, before entering or continuing 147Must 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 148the event loop. An alternative is to use C<EV::FLAG_FORKCHECK> which calls
128this fucntion automatically, at some performance loss (refer to the libev 149this function automatically, at some performance loss (refer to the libev
129documentation). 150documentation).
130 151
152=item $loop->loop_verify
153
154Calls C<ev_verify> to make internal consistency checks (for debugging
155libev) and abort the program if any data structures were found to be
156corrupted.
157
131=item $loop = EV::default_loop [$flags] 158=item $loop = EV::default_loop [$flags]
132 159
133Return the default loop (which is a singleton object). 160Return the default loop (which is a singleton object). Since this module
161already creates the default loop with default flags, specifying flags here
162will not have any effect unless you destroy the default loop first, which
163isn't supported. So in short: don't do it, and if you break it, you get to
164keep the pieces.
134 165
135=back 166=back
136 167
137 168
138=head1 BASIC INTERFACE 169=head1 BASIC INTERFACE
… …
168=item $time = EV::now 199=item $time = EV::now
169 200
170=item $time = $loop->now 201=item $time = $loop->now
171 202
172Returns the time the last event loop iteration has been started. This 203Returns the time the last event loop iteration has been started. This
173is the time that (relative) timers are based on, and refering to it is 204is the time that (relative) timers are based on, and referring to it is
174usually faster then calling EV::time. 205usually faster then calling EV::time.
175 206
207=item EV::now_update
208
209=item $loop->now_update
210
211Establishes the current time by querying the kernel, updating the time
212returned by C<EV::now> in the progress. This is a costly operation and
213is usually done automatically within C<EV::loop>.
214
215This function is rarely useful, but when some event callback runs for a
216very long time without entering the event loop, updating libev's idea of
217the current time is a good idea.
218
219=item EV::suspend
220
221=item $loop->suspend
222
223=item EV::resume
224
225=item $loop->resume
226
227These two functions suspend and resume a loop, for use when the loop is
228not used for a while and timeouts should not be processed.
229
230A typical use case would be an interactive program such as a game: When
231the user presses C<^Z> to suspend the game and resumes it an hour later it
232would be best to handle timeouts as if no time had actually passed while
233the program was suspended. This can be achieved by calling C<suspend>
234in your C<SIGTSTP> handler, sending yourself a C<SIGSTOP> and calling
235C<resume> directly afterwards to resume timer processing.
236
237Effectively, all C<timer> watchers will be delayed by the time spend
238between C<suspend> and C<resume>, and all C<periodic> watchers
239will be rescheduled (that is, they will lose any events that would have
240occured while suspended).
241
242After calling C<suspend> you B<must not> call I<any> function on the given
243loop other than C<resume>, and you B<must not> call C<resume>
244without a previous call to C<suspend>.
245
246Calling C<suspend>/C<resume> has the side effect of updating the event
247loop time (see C<now_update>).
248
176=item $backend = EV::backend 249=item $backend = EV::backend
177 250
178=item $backend = $loop->backend 251=item $backend = $loop->backend
179 252
180Returns an integer describing the backend used by libev (EV::METHOD_SELECT 253Returns an integer describing the backend used by libev (EV::BACKEND_SELECT
181or EV::METHOD_EPOLL). 254or EV::BACKEND_EPOLL).
182 255
183=item EV::loop [$flags] 256=item EV::loop [$flags]
184 257
185=item $loop->loop ([$flags]) 258=item $loop->loop ([$flags])
186 259
… …
206=item $count = EV::loop_count 279=item $count = EV::loop_count
207 280
208=item $count = $loop->loop_count 281=item $count = $loop->loop_count
209 282
210Return the number of times the event loop has polled for new 283Return the number of times the event loop has polled for new
211events. Sometiems useful as a generation counter. 284events. Sometimes useful as a generation counter.
212 285
213=item EV::once $fh_or_undef, $events, $timeout, $cb->($revents) 286=item EV::once $fh_or_undef, $events, $timeout, $cb->($revents)
214 287
215=item $loop->once ($fh_or_undef, $events, $timeout, $cb->($revents)) 288=item $loop->once ($fh_or_undef, $events, $timeout, $cb->($revents))
216 289
… …
256 329
257=item $loop->set_timeout_collect_interval ($time) 330=item $loop->set_timeout_collect_interval ($time)
258 331
259These advanced functions set the minimum block interval when polling for I/O events and the minimum 332These advanced functions set the minimum block interval when polling for I/O events and the minimum
260wait interval for timer events. See the libev documentation at 333wait interval for timer events. See the libev documentation at
261L<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#FUNCTIONS_CONTROLLING_THE_EVENT_LOOP> for 334L<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#FUNCTIONS_CONTROLLING_THE_EVENT_LOOP>
262a more detailed discussion. 335(locally installed as F<EV::libev>) for a more detailed discussion.
263 336
264=back 337=back
265 338
266 339
267=head1 WATCHER OBJECTS 340=head1 WATCHER OBJECTS
268 341
269A watcher is an object that gets created to record your interest in some 342A watcher is an object that gets created to record your interest in some
270event. For instance, if you want to wait for STDIN to become readable, you 343event. For instance, if you want to wait for STDIN to become readable, you
271would create an EV::io watcher for that: 344would create an EV::io watcher for that:
272 345
273 my $watcher = EV::io *STDIN, EV::READ, sub { 346 my $watcher = EV::io *STDIN, EV::READ, sub {
274 my ($watcher, $revents) = @_; 347 my ($watcher, $revents) = @_;
275 warn "yeah, STDIN should now be readable without blocking!\n" 348 warn "yeah, STDIN should now be readable without blocking!\n"
276 }; 349 };
277 350
278All watchers can be active (waiting for events) or inactive (paused). Only 351All watchers can be active (waiting for events) or inactive (paused). Only
279active watchers will have their callbacks invoked. All callbacks will be 352active watchers will have their callbacks invoked. All callbacks will be
280called with at least two arguments: the watcher and a bitmask of received 353called with at least two arguments: the watcher and a bitmask of received
281events. 354events.
282 355
283Each watcher type has its associated bit in revents, so you can use the 356Each watcher type has its associated bit in revents, so you can use the
284same callback for multiple watchers. The event mask is named after the 357same callback for multiple watchers. The event mask is named after the
285type, i..e. EV::child sets EV::CHILD, EV::prepare sets EV::PREPARE, 358type, i.e. EV::child sets EV::CHILD, EV::prepare sets EV::PREPARE,
286EV::periodic sets EV::PERIODIC and so on, with the exception of I/O events 359EV::periodic sets EV::PERIODIC and so on, with the exception of I/O events
287(which can set both EV::READ and EV::WRITE bits), and EV::timer (which 360(which can set both EV::READ and EV::WRITE bits), and EV::timer (which
288uses EV::TIMEOUT). 361uses EV::TIMEOUT).
289 362
290In the rare case where one wants to create a watcher but not start it at 363In the rare case where one wants to create a watcher but not start it at
… …
386because you happen to have this long-running UDP port watcher. 459because you happen to have this long-running UDP port watcher.
387 460
388In this case you can clear the keepalive status, which means that even 461In this case you can clear the keepalive status, which means that even
389though your watcher is active, it won't keep C<EV::loop> from returning. 462though your watcher is active, it won't keep C<EV::loop> from returning.
390 463
391The initial value for keepalive is true (enabled), and you cna change it 464The initial value for keepalive is true (enabled), and you can change it
392any time. 465any time.
393 466
394Example: Register an I/O watcher for some UDP socket but do not keep the 467Example: Register an I/O watcher for some UDP socket but do not keep the
395event loop from running just because of that watcher. 468event loop from running just because of that watcher.
396 469
397 my $udp_socket = ... 470 my $udp_socket = ...
398 my $udp_watcher = EV::io $udp_socket, EV::READ, sub { ... }; 471 my $udp_watcher = EV::io $udp_socket, EV::READ, sub { ... };
399 $1000udp_watcher->keepalive (0); 472 $udp_watcher->keepalive (0);
400 473
401=item $loop = $w->loop 474=item $loop = $w->loop
402 475
403Return the loop that this watcher is attached to. 476Return the loop that this watcher is attached to.
404 477
… …
533This time simply fires at the wallclock time C<$at> and doesn't repeat. It 606This time simply fires at the wallclock time C<$at> and doesn't repeat. It
534will not adjust when a time jump occurs, that is, if it is to be run 607will not adjust when a time jump occurs, that is, if it is to be run
535at January 1st 2011 then it will run when the system time reaches or 608at January 1st 2011 then it will run when the system time reaches or
536surpasses this time. 609surpasses this time.
537 610
538=item * non-repeating interval timer ($interval > 0, $reschedule_cb = 0) 611=item * repeating interval timer ($interval > 0, $reschedule_cb = 0)
539 612
540In this mode the watcher will always be scheduled to time out at the 613In this mode the watcher will always be scheduled to time out at the
541next C<$at + N * $interval> time (for some integer N) and then repeat, 614next C<$at + N * $interval> time (for some integer N) and then repeat,
542regardless of any time jumps. 615regardless of any time jumps.
543 616
… …
561time the periodic watcher gets scheduled, the reschedule callback 634time the periodic watcher gets scheduled, the reschedule callback
562($reschedule_cb) will be called with the watcher as first, and the current 635($reschedule_cb) will be called with the watcher as first, and the current
563time as second argument. 636time as second argument.
564 637
565I<This callback MUST NOT stop or destroy this or any other periodic 638I<This callback MUST NOT stop or destroy this or any other periodic
566watcher, ever>. If you need to stop it, return 1e30 and stop it 639watcher, ever, and MUST NOT call any event loop functions or methods>. If
567afterwards. 640you need to stop it, return 1e30 and stop it afterwards. You may create
641and start a C<EV::prepare> watcher for this task.
568 642
569It must return the next time to trigger, based on the passed time value 643It must return the next time to trigger, based on the passed time value
570(that is, the lowest time value larger than to the second argument). It 644(that is, the lowest time value larger than or equal to to the second
571will usually be called just before the callback will be triggered, but 645argument). It will usually be called just before the callback will be
572might be called at other times, too. 646triggered, but might be called at other times, too.
573 647
574This can be used to create very complex timers, such as a timer that 648This can be used to create very complex timers, such as a timer that
575triggers on each midnight, local time (actually 24 hours after the last 649triggers on each midnight, local time (actually 24 hours after the last
576midnight, to keep the example simple. If you know a way to do it correctly 650midnight, to keep the example simple. If you know a way to do it correctly
577in about the same space (without requiring elaborate modules), drop me a 651in about the same space (without requiring elaborate modules), drop me a
… …
889 # make the dispatcher handle any new stuff 963 # make the dispatcher handle any new stuff
890 ... not shown 964 ... not shown
891 }; 965 };
892 966
893The callbacks of the created watchers will not be called as the watchers 967The callbacks of the created watchers will not be called as the watchers
894are destroyed before this cna happen (remember EV::check gets called 968are destroyed before this can happen (remember EV::check gets called
895first). 969first).
896 970
897The C<check_ns> variant doesn't start (activate) the newly created watcher. 971The C<check_ns> variant doesn't start (activate) the newly created watcher.
898 972
899=back 973=back
… …
930loop, other types of watchers might be handled in a delayed or incorrect 1004loop, other types of watchers might be handled in a delayed or incorrect
931fashion and must not be used). 1005fashion and must not be used).
932 1006
933See the libev documentation at 1007See the libev documentation at
934L<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#code_ev_embed_code_when_one_backend_> 1008L<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#code_ev_embed_code_when_one_backend_>
935for more details. 1009(locally installed as F<EV::libev>) for more details.
936 1010
937In short, this watcher is most useful on BSD systems without working 1011In short, this watcher is most useful on BSD systems without working
938kqueue to still be able to handle a large number of sockets: 1012kqueue to still be able to handle a large number of sockets:
939 1013
940 my $socket_loop; 1014 my $socket_loop;
941 1015
942 # check wether we use SELECT or POLL _and_ KQUEUE is supported 1016 # check wether we use SELECT or POLL _and_ KQUEUE is supported
943 if ( 1017 if (
944 (EV::backend & (EV::BACKEND_POLL | EV::BACKEND_SELECT)) 1018 (EV::backend & (EV::BACKEND_POLL | EV::BACKEND_SELECT))
945 && (EV::supported_backends & EV::embeddable_backends & EV::BACKEND_KQUEUE) 1019 && (EV::supported_backends & EV::embeddable_backends & EV::BACKEND_KQUEUE)
946 ) { 1020 ) {
947 # use kqueue for sockets 1021 # use kqueue for sockets
948 $socket_loop = new EV::Loop EV::BACKEND_KQUEUE | EV::FLAG_NOENV; 1022 $socket_loop = new EV::Loop EV::BACKEND_KQUEUE | EV::FLAG_NOENV;
949 } 1023 }
950 1024
951 # use the default loop otherwise 1025 # use the default loop otherwise
952 $socket_loop ||= EV::default_loop; 1026 $socket_loop ||= EV::default_loop;
953 1027
954=over 4 1028=over 4
955 1029
956=item $w = EV::embed $otherloop, $callback 1030=item $w = EV::embed $otherloop[, $callback]
957 1031
958=item $w = EV::embed_ns $otherloop, $callback 1032=item $w = EV::embed_ns $otherloop[, $callback]
959 1033
960=item $w = $loop->embed ($otherloop, $callback) 1034=item $w = $loop->embed ($otherloop[, $callback])
961 1035
962=item $w = $loop->embed_ns ($otherloop, $callback) 1036=item $w = $loop->embed_ns ($otherloop[, $callback])
963 1037
964Call the callback when the embedded event loop (C<$otherloop>) has any 1038Call the callback when the embedded event loop (C<$otherloop>) has any
965I/O activity. The C<$callback> should alwas be specified as C<undef> in 1039I/O activity. The C<$callback> is optional: if it is missing, then the
966this version of EV, which means the embedded event loop will be managed 1040embedded event loop will be managed automatically (which is recommended),
967automatically. 1041otherwise you have to invoke C<sweep> yourself.
968 1042
969The C<embed_ns> variant doesn't start (activate) the newly created watcher. 1043The C<embed_ns> variant doesn't start (activate) the newly created watcher.
1044
1045=back
1046
1047=head3 ASYNC WATCHERS - how to wake up another event loop
1048
1049Async watchers are provided by EV, but have little use in perl directly, as perl
1050neither supports threads nor direct access to signal handlers or other
1051contexts where they could be of value.
1052
1053It is, however, possible to use them from the XS level.
1054
1055Please see the libev documentation for further details.
1056
1057=over 4
1058
1059=item $w = EV::async $callback
1060
1061=item $w = EV::async_ns $callback
1062
1063=item $w->send
1064
1065=item $bool = $w->async_pending
970 1066
971=back 1067=back
972 1068
973 1069
974=head1 PERL SIGNALS 1070=head1 PERL SIGNALS
… …
1026 1122
1027=head1 SEE ALSO 1123=head1 SEE ALSO
1028 1124
1029L<EV::ADNS> (asynchronous DNS), L<Glib::EV> (makes Glib/Gtk2 use EV as 1125L<EV::ADNS> (asynchronous DNS), L<Glib::EV> (makes Glib/Gtk2 use EV as
1030event loop), L<EV::Glib> (embed Glib into EV), L<Coro::EV> (efficient 1126event loop), L<EV::Glib> (embed Glib into EV), L<Coro::EV> (efficient
1031coroutines with EV), L<Net::SNMP::EV> (asynchronous SNMP). 1127coroutines with EV), L<Net::SNMP::EV> (asynchronous SNMP), L<AnyEvent> for
1128event-loop agnostic and portable event driven programming.
1032 1129
1033=head1 AUTHOR 1130=head1 AUTHOR
1034 1131
1035 Marc Lehmann <schmorp@schmorp.de> 1132 Marc Lehmann <schmorp@schmorp.de>
1036 http://home.schmorp.de/ 1133 http://home.schmorp.de/
1037 1134
1038=cut 1135=cut
1039 1136

Diff Legend

– Removed lines
+ Added lines
< Changed lines
> Changed lines