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

Comparing EV/EV.pm (file contents):
Revision 1.121 by root, Sun Jul 19 03:12:28 2009 UTC vs.
Revision 1.139 by root, Fri Mar 1 11:20:07 2013 UTC

… …
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::run; # 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::run EV::RUN_ONCE; # 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::run EV::RUN_NOWAIT; # try to handle same events, but do not block
55
56=head1 BEFORE YOU START USING THIS MODULE
57
58If you only need timer, I/O, signal, child and idle watchers and not the
59advanced functionality of this module, consider using L<AnyEvent> instead,
60specifically the simplified API described in L<AE>.
61
62When used with EV as backend, the L<AE> API is as fast as the native L<EV>
63API, but your programs/modules will still run with many other event loops.
55 64
56=head1 DESCRIPTION 65=head1 DESCRIPTION
57 66
58This module provides an interface to libev 67This module provides an interface to libev
59(L<http://software.schmorp.de/pkg/libev.html>). While the documentation 68(L<http://software.schmorp.de/pkg/libev.html>). While the documentation
… …
68can use it through the L<AnyEvent> module, stay portable to other event 77can 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) 78loops (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 79and still be faster than with any other event loop currently supported in
71Perl. 80Perl.
72 81
82=head2 PORTING FROM EV 3.X to 4.X
83
84EV version 4 introduces a number of incompatible changes summarised
85here. According to the depreciation strategy used by libev, there is a
86compatibility layer in place so programs should continue to run unchanged
87(the XS interface lacks this layer, so programs using that one need to be
88updated).
89
90This compatibility layer will be switched off in some future release.
91
92All changes relevant to Perl are renames of symbols, functions and
93methods:
94
95 EV::loop => EV::run
96 EV::LOOP_NONBLOCK => EV::RUN_NOWAIT
97 EV::LOOP_ONESHOT => EV::RUN_ONCE
98
99 EV::unloop => EV::break
100 EV::UNLOOP_CANCEL => EV::BREAK_CANCEL
101 EV::UNLOOP_ONE => EV::BREAK_ONE
102 EV::UNLOOP_ALL => EV::BREAK_ALL
103
104 EV::TIMEOUT => EV::TIMER
105
106 EV::loop_count => EV::iteration
107 EV::loop_depth => EV::depth
108 EV::loop_verify => EV::verify
109
110The loop object methods corresponding to the functions above have been
111similarly renamed.
112
73=head2 MODULE EXPORTS 113=head2 MODULE EXPORTS
74 114
75This module does not export any symbols. 115This module does not export any symbols.
76 116
77=cut 117=cut
… …
79package EV; 119package EV;
80 120
81use common::sense; 121use common::sense;
82 122
83BEGIN { 123BEGIN {
84 our $VERSION = '3.7001'; 124 our $VERSION = '4.15';
85 use XSLoader; 125 use XSLoader;
86 XSLoader::load "EV", $VERSION; 126 XSLoader::load "EV", $VERSION;
87} 127}
88 128
89@EV::IO::ISA = 129@EV::IO::ISA =
… …
146Must be called after a fork in the child, before entering or continuing 186Must be called after a fork in the child, before entering or continuing
147the event loop. An alternative is to use C<EV::FLAG_FORKCHECK> which calls 187the event loop. An alternative is to use C<EV::FLAG_FORKCHECK> which calls
148this function automatically, at some performance loss (refer to the libev 188this function automatically, at some performance loss (refer to the libev
149documentation). 189documentation).
150 190
151=item $loop->loop_verify 191=item $loop->verify
152 192
153Calls C<ev_verify> to make internal consistency checks (for debugging 193Calls C<ev_verify> to make internal consistency checks (for debugging
154libev) and abort the program if any data structures were found to be 194libev) and abort the program if any data structures were found to be
155corrupted. 195corrupted.
156 196
… …
250=item $backend = $loop->backend 290=item $backend = $loop->backend
251 291
252Returns an integer describing the backend used by libev (EV::BACKEND_SELECT 292Returns an integer describing the backend used by libev (EV::BACKEND_SELECT
253or EV::BACKEND_EPOLL). 293or EV::BACKEND_EPOLL).
254 294
255=item EV::loop [$flags] 295=item $active = EV::run [$flags]
256 296
257=item $loop->loop ([$flags]) 297=item $active = $loop->run ([$flags])
258 298
259Begin checking for events and calling callbacks. It returns when a 299Begin checking for events and calling callbacks. It returns when a
260callback calls EV::unloop. 300callback calls EV::unloop or the flasg are nonzero (in which case the
301return value is true) or when there are no active watchers which reference
302the loop (keepalive is true), in which case the return value will be
303false. The returnv alue can generally be interpreted as "if true, there is
304more work left to do".
261 305
262The $flags argument can be one of the following: 306The $flags argument can be one of the following:
263 307
264 0 as above 308 0 as above
265 EV::LOOP_ONESHOT block at most once (wait, but do not loop) 309 EV::RUN_ONCE block at most once (wait, but do not loop)
266 EV::LOOP_NONBLOCK do not block at all (fetch/handle events but do not wait) 310 EV::RUN_NOWAIT do not block at all (fetch/handle events but do not wait)
267 311
268=item EV::unloop [$how] 312=item EV::break [$how]
269 313
270=item $loop->unloop ([$how]) 314=item $loop->break ([$how])
271 315
272When called with no arguments or an argument of EV::UNLOOP_ONE, makes the 316When called with no arguments or an argument of EV::BREAK_ONE, makes the
273innermost call to EV::loop return. 317innermost call to EV::loop return.
274 318
275When called with an argument of EV::UNLOOP_ALL, all calls to EV::loop will return as 319When called with an argument of EV::BREAK_ALL, all calls to EV::loop will
276fast as possible. 320return as fast as possible.
277 321
278=item $count = EV::loop_count 322When called with an argument of EV::BREAK_CANCEL, any pending break will
323be cancelled.
279 324
325=item $count = EV::iteration
326
280=item $count = $loop->loop_count 327=item $count = $loop->iteration
281 328
282Return the number of times the event loop has polled for new 329Return the number of times the event loop has polled for new
283events. Sometimes useful as a generation counter. 330events. Sometimes useful as a generation counter.
284 331
285=item EV::once $fh_or_undef, $events, $timeout, $cb->($revents) 332=item EV::once $fh_or_undef, $events, $timeout, $cb->($revents)
… …
299timeout. Otherwise a EV::timer with this value will be started. 346timeout. Otherwise a EV::timer with this value will be started.
300 347
301When an error occurs or either the timeout or I/O watcher triggers, then 348When an error occurs or either the timeout or I/O watcher triggers, then
302the callback will be called with the received event set (in general 349the callback will be called with the received event set (in general
303you can expect it to be a combination of C<EV::ERROR>, C<EV::READ>, 350you can expect it to be a combination of C<EV::ERROR>, C<EV::READ>,
304C<EV::WRITE> and C<EV::TIMEOUT>). 351C<EV::WRITE> and C<EV::TIMER>).
305 352
306EV::once doesn't return anything: the watchers stay active till either 353EV::once doesn't return anything: the watchers stay active till either
307of them triggers, then they will be stopped and freed, and the callback 354of them triggers, then they will be stopped and freed, and the callback
308invoked. 355invoked.
309 356
310=item EV::feed_fd_event ($fd, $revents) 357=item EV::feed_fd_event $fd, $revents
311 358
312=item $loop->feed_fd_event ($fd, $revents) 359=item $loop->feed_fd_event ($fd, $revents)
313 360
314Feed an event on a file descriptor into EV. EV will react to this call as 361Feed an event on a file descriptor into EV. EV will react to this call as
315if the readyness notifications specified by C<$revents> (a combination of 362if the readyness notifications specified by C<$revents> (a combination of
316C<EV::READ> and C<EV::WRITE>) happened on the file descriptor C<$fd>. 363C<EV::READ> and C<EV::WRITE>) happened on the file descriptor C<$fd>.
317 364
318=item EV::feed_signal_event ($signal) 365=item EV::feed_signal_event $signal
319 366
320Feed a signal event into EV. EV will react to this call as if the signal 367Feed a signal event into the default loop. EV will react to this call as
321specified by C<$signal> had occured. 368if the signal specified by C<$signal> had occured.
369
370=item EV::feed_signal $signal
371
372Feed a signal event into EV - unlike C<EV::feed_signal_event>, this works
373regardless of which loop has registered the signal, and is mainly useful
374fro custom signal implementations.
322 375
323=item EV::set_io_collect_interval $time 376=item EV::set_io_collect_interval $time
324 377
325=item $loop->set_io_collect_interval ($time) 378=item $loop->set_io_collect_interval ($time)
326 379
… …
366 419
367Each watcher type has its associated bit in revents, so you can use the 420Each watcher type has its associated bit in revents, so you can use the
368same callback for multiple watchers. The event mask is named after the 421same callback for multiple watchers. The event mask is named after the
369type, i.e. EV::child sets EV::CHILD, EV::prepare sets EV::PREPARE, 422type, i.e. EV::child sets EV::CHILD, EV::prepare sets EV::PREPARE,
370EV::periodic sets EV::PERIODIC and so on, with the exception of I/O events 423EV::periodic sets EV::PERIODIC and so on, with the exception of I/O events
371(which can set both EV::READ and EV::WRITE bits), and EV::timer (which 424(which can set both EV::READ and EV::WRITE bits).
372uses EV::TIMEOUT).
373 425
374In the rare case where one wants to create a watcher but not start it at 426In the rare case where one wants to create a watcher but not start it at
375the same time, each constructor has a variant with a trailing C<_ns> in 427the same time, each constructor has a variant with a trailing C<_ns> in
376its name, e.g. EV::io has a non-starting variant EV::io_ns and so on. 428its name, e.g. EV::io has a non-starting variant EV::io_ns and so on.
377 429
… …
456 508
457=item $previous_state = $w->keepalive ($bool) 509=item $previous_state = $w->keepalive ($bool)
458 510
459Normally, C<EV::loop> will return when there are no active watchers 511Normally, C<EV::loop> will return when there are no active watchers
460(which is a "deadlock" because no progress can be made anymore). This is 512(which is a "deadlock" because no progress can be made anymore). This is
461convinient because it allows you to start your watchers (and your jobs), 513convenient because it allows you to start your watchers (and your jobs),
462call C<EV::loop> once and when it returns you know that all your jobs are 514call C<EV::loop> once and when it returns you know that all your jobs are
463finished (or they forgot to register some watchers for their task :). 515finished (or they forgot to register some watchers for their task :).
464 516
465Sometimes, however, this gets in your way, for example when the module 517Sometimes, however, this gets in your way, for example when the module
466that calls C<EV::loop> (usually the main program) is not the same module 518that calls C<EV::loop> (usually the main program) is not the same module
… …
698 750
699=item $w = EV::signal $signal, $callback 751=item $w = EV::signal $signal, $callback
700 752
701=item $w = EV::signal_ns $signal, $callback 753=item $w = EV::signal_ns $signal, $callback
702 754
755=item $w = $loop->signal ($signal, $callback)
756
757=item $w = $loop->signal_ns ($signal, $callback)
758
703Call the callback when $signal is received (the signal can be specified by 759Call the callback when $signal is received (the signal can be specified by
704number or by name, just as with C<kill> or C<%SIG>). 760number or by name, just as with C<kill> or C<%SIG>).
761
762Only one event loop can grab a given signal - attempting to grab the same
763signal from two EV loops will crash the program immediately or cause data
764corruption.
705 765
706EV will grab the signal for the process (the kernel only allows one 766EV will grab the signal for the process (the kernel only allows one
707component to receive a signal at a time) when you start a signal watcher, 767component to receive a signal at a time) when you start a signal watcher,
708and removes it again when you stop it. Perl does the same when you 768and removes it again when you stop it. Perl does the same when you
709add/remove callbacks to C<%SIG>, so watch out. 769add/remove callbacks to C<%SIG>, so watch out.
… …
934=item $w = $loop->check_ns ($callback) 994=item $w = $loop->check_ns ($callback)
935 995
936Call the callback just after the process wakes up again (after it has 996Call the callback just after the process wakes up again (after it has
937gathered events), but before any other callbacks have been invoked. 997gathered events), but before any other callbacks have been invoked.
938 998
939This is used to integrate other event-based software into the EV 999This can be used to integrate other event-based software into the EV
940mainloop: You register a prepare callback and in there, you create io and 1000mainloop: You register a prepare callback and in there, you create io and
941timer watchers as required by the other software. Here is a real-world 1001timer watchers as required by the other software. Here is a real-world
942example of integrating Net::SNMP (with some details left out): 1002example of integrating Net::SNMP (with some details left out):
943 1003
944 our @snmp_watcher; 1004 our @snmp_watcher;
… …
978The callbacks of the created watchers will not be called as the watchers 1038The callbacks of the created watchers will not be called as the watchers
979are destroyed before this can happen (remember EV::check gets called 1039are destroyed before this can happen (remember EV::check gets called
980first). 1040first).
981 1041
982The C<check_ns> variant doesn't start (activate) the newly created watcher. 1042The C<check_ns> variant doesn't start (activate) the newly created watcher.
1043
1044=item EV::CHECK constant issues
1045
1046Like all other watcher types, there is a bitmask constant for use in
1047C<$revents> and other places. The C<EV::CHECK> is special as it has
1048the same name as the C<CHECK> sub called by Perl. This doesn't cause
1049big issues on newer perls (beginning with 5.8.9), but it means thatthe
1050constant must be I<inlined>, i.e. runtime calls will not work. That means
1051that as long as you always C<use EV> and then C<EV::CHECK> you are on the
1052safe side.
983 1053
984=back 1054=back
985 1055
986 1056
987=head3 FORK WATCHERS - the audacity to resume the event loop after a fork 1057=head3 FORK WATCHERS - the audacity to resume the event loop after a fork
… …
1069 1139
1070=item $w = EV::async $callback 1140=item $w = EV::async $callback
1071 1141
1072=item $w = EV::async_ns $callback 1142=item $w = EV::async_ns $callback
1073 1143
1144=item $w = $loop->async ($callback)
1145
1146=item $w = $loop->async_ns ($callback)
1147
1074=item $w->send 1148=item $w->send
1075 1149
1076=item $bool = $w->async_pending 1150=item $bool = $w->async_pending
1077 1151
1078=back 1152=back
1153
1154=head3 CLEANUP WATCHERS - how to clean up when the event loop goes away
1155
1156Cleanup watchers are not supported on the Perl level, they can only be
1157used via XS currently.
1079 1158
1080 1159
1081=head1 PERL SIGNALS 1160=head1 PERL SIGNALS
1082 1161
1083While Perl signal handling (C<%SIG>) is not affected by EV, the behaviour 1162While Perl signal handling (C<%SIG>) is not affected by EV, the behaviour
… …
1131 1210
11321; 12111;
1133 1212
1134=head1 SEE ALSO 1213=head1 SEE ALSO
1135 1214
1215L<EV::MakeMaker> - MakeMaker interface to XS API, L<EV::ADNS>
1136L<EV::ADNS> (asynchronous DNS), L<Glib::EV> (makes Glib/Gtk2 use EV as 1216(asynchronous DNS), L<Glib::EV> (makes Glib/Gtk2 use EV as event
1137event loop), L<EV::Glib> (embed Glib into EV), L<Coro::EV> (efficient 1217loop), L<EV::Glib> (embed Glib into EV), L<Coro::EV> (efficient thread
1138coroutines with EV), L<Net::SNMP::EV> (asynchronous SNMP), L<AnyEvent> for 1218integration), L<Net::SNMP::EV> (asynchronous SNMP), L<AnyEvent> for
1139event-loop agnostic and portable event driven programming. 1219event-loop agnostic and portable event driven programming.
1140 1220
1141=head1 AUTHOR 1221=head1 AUTHOR
1142 1222
1143 Marc Lehmann <schmorp@schmorp.de> 1223 Marc Lehmann <schmorp@schmorp.de>

Diff Legend

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