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1=head1 NAME 1=head1 NAME
2 2
3AnyEvent - provide framework for multiple event loops 3AnyEvent - the DBI of event loop programming
4 4
5EV, Event, Glib, Tk, Perl, Event::Lib, Qt and POE are various supported 5EV, Event, Glib, Tk, Perl, Event::Lib, Irssi, rxvt-unicode, IO::Async, Qt
6event loops. 6and POE are various supported event loops/environments.
7 7
8=head1 SYNOPSIS 8=head1 SYNOPSIS
9 9
10 use AnyEvent; 10 use AnyEvent;
11 11
40=head1 INTRODUCTION/TUTORIAL 40=head1 INTRODUCTION/TUTORIAL
41 41
42This manpage is mainly a reference manual. If you are interested 42This manpage is mainly a reference manual. If you are interested
43in a tutorial or some gentle introduction, have a look at the 43in a tutorial or some gentle introduction, have a look at the
44L<AnyEvent::Intro> manpage. 44L<AnyEvent::Intro> manpage.
45
46=head1 SUPPORT
47
48There is a mailinglist for discussing all things AnyEvent, and an IRC
49channel, too.
50
51See the AnyEvent project page at the B<Schmorpforge Ta-Sa Software
52Repository>, at L<http://anyevent.schmorp.de>, for more info.
45 53
46=head1 WHY YOU SHOULD USE THIS MODULE (OR NOT) 54=head1 WHY YOU SHOULD USE THIS MODULE (OR NOT)
47 55
48Glib, POE, IO::Async, Event... CPAN offers event models by the dozen 56Glib, POE, IO::Async, Event... CPAN offers event models by the dozen
49nowadays. So what is different about AnyEvent? 57nowadays. So what is different about AnyEvent?
173my variables are only visible after the statement in which they are 181my variables are only visible after the statement in which they are
174declared. 182declared.
175 183
176=head2 I/O WATCHERS 184=head2 I/O WATCHERS
177 185
186 $w = AnyEvent->io (
187 fh => <filehandle_or_fileno>,
188 poll => <"r" or "w">,
189 cb => <callback>,
190 );
191
178You can create an I/O watcher by calling the C<< AnyEvent->io >> method 192You can create an I/O watcher by calling the C<< AnyEvent->io >> method
179with the following mandatory key-value pairs as arguments: 193with the following mandatory key-value pairs as arguments:
180 194
181C<fh> is the Perl I<file handle> (or a naked file descriptor) to watch 195C<fh> is the Perl I<file handle> (or a naked file descriptor) to watch
182for events (AnyEvent might or might not keep a reference to this file 196for events (AnyEvent might or might not keep a reference to this file
211 undef $w; 225 undef $w;
212 }); 226 });
213 227
214=head2 TIME WATCHERS 228=head2 TIME WATCHERS
215 229
230 $w = AnyEvent->timer (after => <seconds>, cb => <callback>);
231
232 $w = AnyEvent->timer (
233 after => <fractional_seconds>,
234 interval => <fractional_seconds>,
235 cb => <callback>,
236 );
237
216You can create a time watcher by calling the C<< AnyEvent->timer >> 238You can create a time watcher by calling the C<< AnyEvent->timer >>
217method with the following mandatory arguments: 239method with the following mandatory arguments:
218 240
219C<after> specifies after how many seconds (fractional values are 241C<after> specifies after how many seconds (fractional values are
220supported) the callback should be invoked. C<cb> is the callback to invoke 242supported) the callback should be invoked. C<cb> is the callback to invoke
341might affect timers and time-outs. 363might affect timers and time-outs.
342 364
343When this is the case, you can call this method, which will update the 365When this is the case, you can call this method, which will update the
344event loop's idea of "current time". 366event loop's idea of "current time".
345 367
368A typical example would be a script in a web server (e.g. C<mod_perl>) -
369when mod_perl executes the script, then the event loop will have the wrong
370idea about the "current time" (being potentially far in the past, when the
371script ran the last time). In that case you should arrange a call to C<<
372AnyEvent->now_update >> each time the web server process wakes up again
373(e.g. at the start of your script, or in a handler).
374
346Note that updating the time I<might> cause some events to be handled. 375Note that updating the time I<might> cause some events to be handled.
347 376
348=back 377=back
349 378
350=head2 SIGNAL WATCHERS 379=head2 SIGNAL WATCHERS
380
381 $w = AnyEvent->signal (signal => <uppercase_signal_name>, cb => <callback>);
351 382
352You can watch for signals using a signal watcher, C<signal> is the signal 383You can watch for signals using a signal watcher, C<signal> is the signal
353I<name> in uppercase and without any C<SIG> prefix, C<cb> is the Perl 384I<name> in uppercase and without any C<SIG> prefix, C<cb> is the Perl
354callback to be invoked whenever a signal occurs. 385callback to be invoked whenever a signal occurs.
355 386
368 399
369This watcher might use C<%SIG> (depending on the event loop used), 400This watcher might use C<%SIG> (depending on the event loop used),
370so programs overwriting those signals directly will likely not work 401so programs overwriting those signals directly will likely not work
371correctly. 402correctly.
372 403
404Example: exit on SIGINT
405
406 my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });
407
408=head3 Restart Behaviour
409
410While restart behaviour is up to the event loop implementation, most will
411not restart syscalls (that includes L<Async::Interrupt> and AnyEvent's
412pure perl implementation).
413
414=head3 Safe/Unsafe Signals
415
416Perl signals can be either "safe" (synchronous to opcode handling) or
417"unsafe" (asynchronous) - the former might get delayed indefinitely, the
418latter might corrupt your memory.
419
420AnyEvent signal handlers are, in addition, synchronous to the event loop,
421i.e. they will not interrupt your running perl program but will only be
422called as part of the normal event handling (just like timer, I/O etc.
423callbacks, too).
424
425=head3 Signal Races, Delays and Workarounds
426
373Also note that many event loops (e.g. Glib, Tk, Qt, IO::Async) do not 427Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching
374support attaching callbacks to signals, which is a pity, as you cannot do 428callbacks to signals in a generic way, which is a pity, as you cannot
375race-free signal handling in perl. AnyEvent will try to do it's best, but 429do race-free signal handling in perl, requiring C libraries for
430this. AnyEvent will try to do it's best, which means in some cases,
376in some cases, signals will be delayed. The maximum time a signal might 431signals will be delayed. The maximum time a signal might be delayed is
377be delayed is specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 432specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 seconds). This
378seconds). This variable can be changed only before the first signal 433variable can be changed only before the first signal watcher is created,
379watcher is created, and should be left alone otherwise. Higher values 434and should be left alone otherwise. This variable determines how often
435AnyEvent polls for signals (in case a wake-up was missed). Higher values
380will cause fewer spurious wake-ups, which is better for power and CPU 436will cause fewer spurious wake-ups, which is better for power and CPU
437saving.
438
381saving. All these problems can be avoided by installing the optional 439All these problems can be avoided by installing the optional
382L<Async::Interrupt> module. 440L<Async::Interrupt> module, which works with most event loops. It will not
383 441work with inherently broken event loops such as L<Event> or L<Event::Lib>
384Example: exit on SIGINT 442(and not with L<POE> currently, as POE does it's own workaround with
385 443one-second latency). For those, you just have to suffer the delays.
386 my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });
387 444
388=head2 CHILD PROCESS WATCHERS 445=head2 CHILD PROCESS WATCHERS
389 446
447 $w = AnyEvent->child (pid => <process id>, cb => <callback>);
448
390You can also watch on a child process exit and catch its exit status. 449You can also watch on a child process exit and catch its exit status.
391 450
392The child process is specified by the C<pid> argument (if set to C<0>, it 451The child process is specified by the C<pid> argument (one some backends,
393watches for any child process exit). The watcher will triggered only when 452using C<0> watches for any child process exit, on others this will
394the child process has finished and an exit status is available, not on 453croak). The watcher will be triggered only when the child process has
395any trace events (stopped/continued). 454finished and an exit status is available, not on any trace events
455(stopped/continued).
396 456
397The callback will be called with the pid and exit status (as returned by 457The callback will be called with the pid and exit status (as returned by
398waitpid), so unlike other watcher types, you I<can> rely on child watcher 458waitpid), so unlike other watcher types, you I<can> rely on child watcher
399callback arguments. 459callback arguments.
400 460
441 # do something else, then wait for process exit 501 # do something else, then wait for process exit
442 $done->recv; 502 $done->recv;
443 503
444=head2 IDLE WATCHERS 504=head2 IDLE WATCHERS
445 505
446Sometimes there is a need to do something, but it is not so important 506 $w = AnyEvent->idle (cb => <callback>);
447to do it instantly, but only when there is nothing better to do. This
448"nothing better to do" is usually defined to be "no other events need
449attention by the event loop".
450 507
451Idle watchers ideally get invoked when the event loop has nothing 508Repeatedly invoke the callback after the process becomes idle, until
452better to do, just before it would block the process to wait for new 509either the watcher is destroyed or new events have been detected.
453events. Instead of blocking, the idle watcher is invoked.
454 510
455Most event loops unfortunately do not really support idle watchers (only 511Idle watchers are useful when there is a need to do something, but it
512is not so important (or wise) to do it instantly. The callback will be
513invoked only when there is "nothing better to do", which is usually
514defined as "all outstanding events have been handled and no new events
515have been detected". That means that idle watchers ideally get invoked
516when the event loop has just polled for new events but none have been
517detected. Instead of blocking to wait for more events, the idle watchers
518will be invoked.
519
520Unfortunately, most event loops do not really support idle watchers (only
456EV, Event and Glib do it in a usable fashion) - for the rest, AnyEvent 521EV, Event and Glib do it in a usable fashion) - for the rest, AnyEvent
457will simply call the callback "from time to time". 522will simply call the callback "from time to time".
458 523
459Example: read lines from STDIN, but only process them when the 524Example: read lines from STDIN, but only process them when the
460program is otherwise idle: 525program is otherwise idle:
476 }); 541 });
477 }); 542 });
478 543
479=head2 CONDITION VARIABLES 544=head2 CONDITION VARIABLES
480 545
546 $cv = AnyEvent->condvar;
547
548 $cv->send (<list>);
549 my @res = $cv->recv;
550
481If you are familiar with some event loops you will know that all of them 551If you are familiar with some event loops you will know that all of them
482require you to run some blocking "loop", "run" or similar function that 552require you to run some blocking "loop", "run" or similar function that
483will actively watch for new events and call your callbacks. 553will actively watch for new events and call your callbacks.
484 554
485AnyEvent is slightly different: it expects somebody else to run the event 555AnyEvent is slightly different: it expects somebody else to run the event
504Condition variables are similar to callbacks, except that you can 574Condition variables are similar to callbacks, except that you can
505optionally wait for them. They can also be called merge points - points 575optionally wait for them. They can also be called merge points - points
506in time where multiple outstanding events have been processed. And yet 576in time where multiple outstanding events have been processed. And yet
507another way to call them is transactions - each condition variable can be 577another way to call them is transactions - each condition variable can be
508used to represent a transaction, which finishes at some point and delivers 578used to represent a transaction, which finishes at some point and delivers
509a result. 579a result. And yet some people know them as "futures" - a promise to
580compute/deliver something that you can wait for.
510 581
511Condition variables are very useful to signal that something has finished, 582Condition variables are very useful to signal that something has finished,
512for example, if you write a module that does asynchronous http requests, 583for example, if you write a module that does asynchronous http requests,
513then a condition variable would be the ideal candidate to signal the 584then a condition variable would be the ideal candidate to signal the
514availability of results. The user can either act when the callback is 585availability of results. The user can either act when the callback is
548 after => 1, 619 after => 1,
549 cb => sub { $result_ready->send }, 620 cb => sub { $result_ready->send },
550 ); 621 );
551 622
552 # this "blocks" (while handling events) till the callback 623 # this "blocks" (while handling events) till the callback
553 # calls -<send 624 # calls ->send
554 $result_ready->recv; 625 $result_ready->recv;
555 626
556Example: wait for a timer, but take advantage of the fact that condition 627Example: wait for a timer, but take advantage of the fact that condition
557variables are also callable directly. 628variables are also callable directly.
558 629
622one. For example, a function that pings many hosts in parallel might want 693one. For example, a function that pings many hosts in parallel might want
623to use a condition variable for the whole process. 694to use a condition variable for the whole process.
624 695
625Every call to C<< ->begin >> will increment a counter, and every call to 696Every call to C<< ->begin >> will increment a counter, and every call to
626C<< ->end >> will decrement it. If the counter reaches C<0> in C<< ->end 697C<< ->end >> will decrement it. If the counter reaches C<0> in C<< ->end
627>>, the (last) callback passed to C<begin> will be executed. That callback 698>>, the (last) callback passed to C<begin> will be executed, passing the
628is I<supposed> to call C<< ->send >>, but that is not required. If no 699condvar as first argument. That callback is I<supposed> to call C<< ->send
629callback was set, C<send> will be called without any arguments. 700>>, but that is not required. If no group callback was set, C<send> will
701be called without any arguments.
630 702
631You can think of C<< $cv->send >> giving you an OR condition (one call 703You can think of C<< $cv->send >> giving you an OR condition (one call
632sends), while C<< $cv->begin >> and C<< $cv->end >> giving you an AND 704sends), while C<< $cv->begin >> and C<< $cv->end >> giving you an AND
633condition (all C<begin> calls must be C<end>'ed before the condvar sends). 705condition (all C<begin> calls must be C<end>'ed before the condvar sends).
634 706
661begung can potentially be zero: 733begung can potentially be zero:
662 734
663 my $cv = AnyEvent->condvar; 735 my $cv = AnyEvent->condvar;
664 736
665 my %result; 737 my %result;
666 $cv->begin (sub { $cv->send (\%result) }); 738 $cv->begin (sub { shift->send (\%result) });
667 739
668 for my $host (@list_of_hosts) { 740 for my $host (@list_of_hosts) {
669 $cv->begin; 741 $cv->begin;
670 ping_host_then_call_callback $host, sub { 742 ping_host_then_call_callback $host, sub {
671 $result{$host} = ...; 743 $result{$host} = ...;
746=item $cb = $cv->cb ($cb->($cv)) 818=item $cb = $cv->cb ($cb->($cv))
747 819
748This is a mutator function that returns the callback set and optionally 820This is a mutator function that returns the callback set and optionally
749replaces it before doing so. 821replaces it before doing so.
750 822
751The callback will be called when the condition becomes "true", i.e. when 823The callback will be called when the condition becomes (or already was)
752C<send> or C<croak> are called, with the only argument being the condition 824"true", i.e. when C<send> or C<croak> are called (or were called), with
753variable itself. Calling C<recv> inside the callback or at any later time 825the only argument being the condition variable itself. Calling C<recv>
754is guaranteed not to block. 826inside the callback or at any later time is guaranteed not to block.
755 827
756=back 828=back
757 829
758=head1 SUPPORTED EVENT LOOPS/BACKENDS 830=head1 SUPPORTED EVENT LOOPS/BACKENDS
759 831
762=over 4 834=over 4
763 835
764=item Backends that are autoprobed when no other event loop can be found. 836=item Backends that are autoprobed when no other event loop can be found.
765 837
766EV is the preferred backend when no other event loop seems to be in 838EV is the preferred backend when no other event loop seems to be in
767use. If EV is not installed, then AnyEvent will try Event, and, failing 839use. If EV is not installed, then AnyEvent will fall back to its own
768that, will fall back to its own pure-perl implementation, which is 840pure-perl implementation, which is available everywhere as it comes with
769available everywhere as it comes with AnyEvent itself. 841AnyEvent itself.
770 842
771 AnyEvent::Impl::EV based on EV (interface to libev, best choice). 843 AnyEvent::Impl::EV based on EV (interface to libev, best choice).
772 AnyEvent::Impl::Event based on Event, very stable, few glitches.
773 AnyEvent::Impl::Perl pure-perl implementation, fast and portable. 844 AnyEvent::Impl::Perl pure-perl implementation, fast and portable.
774 845
775=item Backends that are transparently being picked up when they are used. 846=item Backends that are transparently being picked up when they are used.
776 847
777These will be used when they are currently loaded when the first watcher 848These will be used when they are currently loaded when the first watcher
778is created, in which case it is assumed that the application is using 849is created, in which case it is assumed that the application is using
779them. This means that AnyEvent will automatically pick the right backend 850them. This means that AnyEvent will automatically pick the right backend
780when the main program loads an event module before anything starts to 851when the main program loads an event module before anything starts to
781create watchers. Nothing special needs to be done by the main program. 852create watchers. Nothing special needs to be done by the main program.
782 853
854 AnyEvent::Impl::Event based on Event, very stable, few glitches.
783 AnyEvent::Impl::Glib based on Glib, slow but very stable. 855 AnyEvent::Impl::Glib based on Glib, slow but very stable.
784 AnyEvent::Impl::Tk based on Tk, very broken. 856 AnyEvent::Impl::Tk based on Tk, very broken.
785 AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse. 857 AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.
786 AnyEvent::Impl::POE based on POE, very slow, some limitations. 858 AnyEvent::Impl::POE based on POE, very slow, some limitations.
859 AnyEvent::Impl::Irssi used when running within irssi.
787 860
788=item Backends with special needs. 861=item Backends with special needs.
789 862
790Qt requires the Qt::Application to be instantiated first, but will 863Qt requires the Qt::Application to be instantiated first, but will
791otherwise be picked up automatically. As long as the main program 864otherwise be picked up automatically. As long as the main program
865event module detection too early, for example, L<AnyEvent::AIO> creates 938event module detection too early, for example, L<AnyEvent::AIO> creates
866and installs the global L<IO::AIO> watcher in a C<post_detect> block to 939and installs the global L<IO::AIO> watcher in a C<post_detect> block to
867avoid autodetecting the event module at load time. 940avoid autodetecting the event module at load time.
868 941
869If called in scalar or list context, then it creates and returns an object 942If called in scalar or list context, then it creates and returns an object
870that automatically removes the callback again when it is destroyed. See 943that automatically removes the callback again when it is destroyed (or
944C<undef> when the hook was immediately executed). See L<AnyEvent::AIO> for
871L<Coro::BDB> for a case where this is useful. 945a case where this is useful.
946
947Example: Create a watcher for the IO::AIO module and store it in
948C<$WATCHER>. Only do so after the event loop is initialised, though.
949
950 our WATCHER;
951
952 my $guard = AnyEvent::post_detect {
953 $WATCHER = AnyEvent->io (fh => IO::AIO::poll_fileno, poll => 'r', cb => \&IO::AIO::poll_cb);
954 };
955
956 # the ||= is important in case post_detect immediately runs the block,
957 # as to not clobber the newly-created watcher. assigning both watcher and
958 # post_detect guard to the same variable has the advantage of users being
959 # able to just C<undef $WATCHER> if the watcher causes them grief.
960
961 $WATCHER ||= $guard;
872 962
873=item @AnyEvent::post_detect 963=item @AnyEvent::post_detect
874 964
875If there are any code references in this array (you can C<push> to it 965If there are any code references in this array (you can C<push> to it
876before or after loading AnyEvent), then they will called directly after 966before or after loading AnyEvent), then they will called directly after
879You should check C<$AnyEvent::MODEL> before adding to this array, though: 969You should check C<$AnyEvent::MODEL> before adding to this array, though:
880if it is defined then the event loop has already been detected, and the 970if it is defined then the event loop has already been detected, and the
881array will be ignored. 971array will be ignored.
882 972
883Best use C<AnyEvent::post_detect { BLOCK }> when your application allows 973Best use C<AnyEvent::post_detect { BLOCK }> when your application allows
884it,as it takes care of these details. 974it, as it takes care of these details.
885 975
886This variable is mainly useful for modules that can do something useful 976This variable is mainly useful for modules that can do something useful
887when AnyEvent is used and thus want to know when it is initialised, but do 977when AnyEvent is used and thus want to know when it is initialised, but do
888not need to even load it by default. This array provides the means to hook 978not need to even load it by default. This array provides the means to hook
889into AnyEvent passively, without loading it. 979into AnyEvent passively, without loading it.
980
981Example: To load Coro::AnyEvent whenever Coro and AnyEvent are used
982together, you could put this into Coro (this is the actual code used by
983Coro to accomplish this):
984
985 if (defined $AnyEvent::MODEL) {
986 # AnyEvent already initialised, so load Coro::AnyEvent
987 require Coro::AnyEvent;
988 } else {
989 # AnyEvent not yet initialised, so make sure to load Coro::AnyEvent
990 # as soon as it is
991 push @AnyEvent::post_detect, sub { require Coro::AnyEvent };
992 }
890 993
891=back 994=back
892 995
893=head1 WHAT TO DO IN A MODULE 996=head1 WHAT TO DO IN A MODULE
894 997
1043 1146
1044package AnyEvent; 1147package AnyEvent;
1045 1148
1046# basically a tuned-down version of common::sense 1149# basically a tuned-down version of common::sense
1047sub common_sense { 1150sub common_sense {
1048 # no warnings 1151 # from common:.sense 1.0
1049 ${^WARNING_BITS} ^= ${^WARNING_BITS}; 1152 ${^WARNING_BITS} = "\xfc\x3f\x33\x00\x0f\xf3\xcf\xc0\xf3\xfc\x33\x00";
1050 # use strict vars subs 1153 # use strict vars subs - NO UTF-8, as Util.pm doesn't like this atm. (uts46data.pl)
1051 $^H |= 0x00000600; 1154 $^H |= 0x00000600;
1052} 1155}
1053 1156
1054BEGIN { AnyEvent::common_sense } 1157BEGIN { AnyEvent::common_sense }
1055 1158
1056use Carp (); 1159use Carp ();
1057 1160
1058our $VERSION = 4.83; 1161our $VERSION = '5.23';
1059our $MODEL; 1162our $MODEL;
1060 1163
1061our $AUTOLOAD; 1164our $AUTOLOAD;
1062our @ISA; 1165our @ISA;
1063 1166
1064our @REGISTRY; 1167our @REGISTRY;
1065
1066our $WIN32;
1067 1168
1068our $VERBOSE; 1169our $VERBOSE;
1069 1170
1070BEGIN { 1171BEGIN {
1071 eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }"; 1172 eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }";
1088 for reverse split /\s*,\s*/, 1189 for reverse split /\s*,\s*/,
1089 $ENV{PERL_ANYEVENT_PROTOCOLS} || "ipv4,ipv6"; 1190 $ENV{PERL_ANYEVENT_PROTOCOLS} || "ipv4,ipv6";
1090} 1191}
1091 1192
1092my @models = ( 1193my @models = (
1093 [EV:: => AnyEvent::Impl::EV::], 1194 [EV:: => AnyEvent::Impl::EV:: , 1],
1094 [Event:: => AnyEvent::Impl::Event::],
1095 [AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl::], 1195 [AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl:: , 1],
1096 # everything below here will not be autoprobed 1196 # everything below here will not (normally) be autoprobed
1097 # as the pureperl backend should work everywhere 1197 # as the pureperl backend should work everywhere
1098 # and is usually faster 1198 # and is usually faster
1199 [Event:: => AnyEvent::Impl::Event::, 1],
1099 [Glib:: => AnyEvent::Impl::Glib::], # becomes extremely slow with many watchers 1200 [Glib:: => AnyEvent::Impl::Glib:: , 1], # becomes extremely slow with many watchers
1100 [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy 1201 [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy
1202 [Irssi:: => AnyEvent::Impl::Irssi::], # Irssi has a bogus "Event" package
1101 [Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles 1203 [Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles
1102 [Qt:: => AnyEvent::Impl::Qt::], # requires special main program 1204 [Qt:: => AnyEvent::Impl::Qt::], # requires special main program
1103 [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza 1205 [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza
1104 [Wx:: => AnyEvent::Impl::POE::], 1206 [Wx:: => AnyEvent::Impl::POE::],
1105 [Prima:: => AnyEvent::Impl::POE::], 1207 [Prima:: => AnyEvent::Impl::POE::],
1106 # IO::Async is just too broken - we would need workarounds for its 1208 # IO::Async is just too broken - we would need workarounds for its
1107 # byzantine signal and broken child handling, among others. 1209 # byzantine signal and broken child handling, among others.
1108 # IO::Async is rather hard to detect, as it doesn't have any 1210 # IO::Async is rather hard to detect, as it doesn't have any
1109 # obvious default class. 1211 # obvious default class.
1110# [IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program 1212 [IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program
1111# [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program 1213 [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program
1112# [IO::Async::Notifier:: => AnyEvent::Impl::IOAsync::], # requires special main program 1214 [IO::Async::Notifier:: => AnyEvent::Impl::IOAsync::], # requires special main program
1215 [AnyEvent::Impl::IOAsync:: => AnyEvent::Impl::IOAsync::], # requires special main program
1113); 1216);
1114 1217
1115our %method = map +($_ => 1), 1218our %method = map +($_ => 1),
1116 qw(io timer time now now_update signal child idle condvar one_event DESTROY); 1219 qw(io timer time now now_update signal child idle condvar one_event DESTROY);
1117 1220
1121 my ($cb) = @_; 1224 my ($cb) = @_;
1122 1225
1123 if ($MODEL) { 1226 if ($MODEL) {
1124 $cb->(); 1227 $cb->();
1125 1228
1126 1 1229 undef
1127 } else { 1230 } else {
1128 push @post_detect, $cb; 1231 push @post_detect, $cb;
1129 1232
1130 defined wantarray 1233 defined wantarray
1131 ? bless \$cb, "AnyEvent::Util::postdetect" 1234 ? bless \$cb, "AnyEvent::Util::postdetect"
1163 } 1266 }
1164 } 1267 }
1165 } 1268 }
1166 1269
1167 unless ($MODEL) { 1270 unless ($MODEL) {
1168 # try to load a model 1271 # try to autoload a model
1169
1170 for (@REGISTRY, @models) { 1272 for (@REGISTRY, @models) {
1171 my ($package, $model) = @$_; 1273 my ($package, $model, $autoload) = @$_;
1274 if (
1275 $autoload
1172 if (eval "require $package" 1276 and eval "require $package"
1173 and ${"$package\::VERSION"} > 0 1277 and ${"$package\::VERSION"} > 0
1174 and eval "require $model") { 1278 and eval "require $model"
1279 ) {
1175 $MODEL = $model; 1280 $MODEL = $model;
1176 warn "AnyEvent: autoprobed model '$model', using it.\n" if $VERBOSE >= 2; 1281 warn "AnyEvent: autoloaded model '$model', using it.\n" if $VERBOSE >= 2;
1177 last; 1282 last;
1178 } 1283 }
1179 } 1284 }
1180 1285
1181 $MODEL 1286 $MODEL
1222 # we assume CLOEXEC is already set by perl in all important cases 1327 # we assume CLOEXEC is already set by perl in all important cases
1223 1328
1224 ($fh2, $rw) 1329 ($fh2, $rw)
1225} 1330}
1226 1331
1332=head1 SIMPLIFIED AE API
1333
1334Starting with version 5.0, AnyEvent officially supports a second, much
1335simpler, API that is designed to reduce the calling, typing and memory
1336overhead.
1337
1338See the L<AE> manpage for details.
1339
1340=cut
1341
1342package AE;
1343
1344our $VERSION = $AnyEvent::VERSION;
1345
1346sub io($$$) {
1347 AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2])
1348}
1349
1350sub timer($$$) {
1351 AnyEvent->timer (after => $_[0], interval => $_[1], cb => $_[2])
1352}
1353
1354sub signal($$) {
1355 AnyEvent->signal (signal => $_[0], cb => $_[1])
1356}
1357
1358sub child($$) {
1359 AnyEvent->child (pid => $_[0], cb => $_[1])
1360}
1361
1362sub idle($) {
1363 AnyEvent->idle (cb => $_[0])
1364}
1365
1366sub cv(;&) {
1367 AnyEvent->condvar (@_ ? (cb => $_[0]) : ())
1368}
1369
1370sub now() {
1371 AnyEvent->now
1372}
1373
1374sub now_update() {
1375 AnyEvent->now_update
1376}
1377
1378sub time() {
1379 AnyEvent->time
1380}
1381
1227package AnyEvent::Base; 1382package AnyEvent::Base;
1228 1383
1229# default implementations for many methods 1384# default implementations for many methods
1230 1385
1231sub _time { 1386sub _time() {
1232 # probe for availability of Time::HiRes 1387 # probe for availability of Time::HiRes
1233 if (eval "use Time::HiRes (); Time::HiRes::time (); 1") { 1388 if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {
1234 warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8; 1389 warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8;
1235 *_time = \&Time::HiRes::time; 1390 *_time = \&Time::HiRes::time;
1236 # if (eval "use POSIX (); (POSIX::times())... 1391 # if (eval "use POSIX (); (POSIX::times())...
1253} 1408}
1254 1409
1255# default implementation for ->signal 1410# default implementation for ->signal
1256 1411
1257our $HAVE_ASYNC_INTERRUPT; 1412our $HAVE_ASYNC_INTERRUPT;
1413
1414sub _have_async_interrupt() {
1415 $HAVE_ASYNC_INTERRUPT = 1*(!$ENV{PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT}
1416 && eval "use Async::Interrupt 1.02 (); 1")
1417 unless defined $HAVE_ASYNC_INTERRUPT;
1418
1419 $HAVE_ASYNC_INTERRUPT
1420}
1421
1258our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO); 1422our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO);
1259our (%SIG_ASY, %SIG_ASY_W); 1423our (%SIG_ASY, %SIG_ASY_W);
1260our ($SIG_COUNT, $SIG_TW); 1424our ($SIG_COUNT, $SIG_TW);
1261 1425
1262sub _signal_exec { 1426sub _signal_exec {
1263 $HAVE_ASYNC_INTERRUPT 1427 $HAVE_ASYNC_INTERRUPT
1264 ? $SIGPIPE_R->drain 1428 ? $SIGPIPE_R->drain
1265 : sysread $SIGPIPE_R, my $dummy, 9; 1429 : sysread $SIGPIPE_R, (my $dummy), 9;
1266 1430
1267 while (%SIG_EV) { 1431 while (%SIG_EV) {
1268 for (keys %SIG_EV) { 1432 for (keys %SIG_EV) {
1269 delete $SIG_EV{$_}; 1433 delete $SIG_EV{$_};
1270 $_->() for values %{ $SIG_CB{$_} || {} }; 1434 $_->() for values %{ $SIG_CB{$_} || {} };
1271 } 1435 }
1272 } 1436 }
1273} 1437}
1274 1438
1439# install a dummy wakeup watcher to reduce signal catching latency
1275sub _signal { 1440sub _sig_add() {
1276 my (undef, %arg) = @_; 1441 unless ($SIG_COUNT++) {
1442 # try to align timer on a full-second boundary, if possible
1443 my $NOW = AE::now;
1277 1444
1278 my $signal = uc $arg{signal} 1445 $SIG_TW = AE::timer
1279 or Carp::croak "required option 'signal' is missing"; 1446 $MAX_SIGNAL_LATENCY - ($NOW - int $NOW),
1280 1447 $MAX_SIGNAL_LATENCY,
1281 $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; 1448 sub { } # just for the PERL_ASYNC_CHECK
1282
1283 if ($HAVE_ASYNC_INTERRUPT) {
1284 # async::interrupt
1285
1286 $SIG_ASY{$signal} ||= do {
1287 my $asy = new Async::Interrupt
1288 cb => sub { undef $SIG_EV{$signal} },
1289 signal => $signal,
1290 pipe => [$SIGPIPE_R->filenos],
1291 ;
1292 $asy->pipe_autodrain (0);
1293
1294 $asy
1295 }; 1449 ;
1296
1297 } else {
1298 # pure perl
1299
1300 $SIG{$signal} ||= sub {
1301 local $!;
1302 syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;
1303 undef $SIG_EV{$signal};
1304 };
1305
1306 # can't do signal processing without introducing races in pure perl,
1307 # so limit the signal latency.
1308 ++$SIG_COUNT;
1309 $SIG_TW ||= AnyEvent->timer (
1310 after => $MAX_SIGNAL_LATENCY,
1311 interval => $MAX_SIGNAL_LATENCY,
1312 cb => sub { }, # just for the PERL_ASYNC_CHECK
1313 );
1314 } 1450 }
1315
1316 bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
1317} 1451}
1318 1452
1319sub signal { 1453sub _sig_del {
1320 # probe for availability of Async::Interrupt
1321 if (!$ENV{PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT} && eval "use Async::Interrupt 0.6 (); 1") {
1322 warn "AnyEvent: using Async::Interrupt for race-free signal handling.\n" if $VERBOSE >= 8;
1323
1324 $HAVE_ASYNC_INTERRUPT = 1;
1325 $SIGPIPE_R = new Async::Interrupt::EventPipe;
1326 $SIG_IO = AnyEvent->io (fh => $SIGPIPE_R->fileno, poll => "r", cb => \&_signal_exec);
1327
1328 } else {
1329 warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8;
1330
1331 require Fcntl;
1332
1333 if (AnyEvent::WIN32) {
1334 require AnyEvent::Util;
1335
1336 ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
1337 AnyEvent::Util::fh_nonblocking ($SIGPIPE_R) if $SIGPIPE_R;
1338 AnyEvent::Util::fh_nonblocking ($SIGPIPE_W) if $SIGPIPE_W; # just in case
1339 } else {
1340 pipe $SIGPIPE_R, $SIGPIPE_W;
1341 fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R;
1342 fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case
1343
1344 # not strictly required, as $^F is normally 2, but let's make sure...
1345 fcntl $SIGPIPE_R, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;
1346 fcntl $SIGPIPE_W, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;
1347 }
1348
1349 $SIGPIPE_R
1350 or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";
1351
1352 $SIG_IO = AnyEvent->io (fh => $SIGPIPE_R, poll => "r", cb => \&_signal_exec);
1353 }
1354
1355 *signal = \&_signal;
1356 &signal
1357}
1358
1359sub AnyEvent::Base::signal::DESTROY {
1360 my ($signal, $cb) = @{$_[0]};
1361
1362 undef $SIG_TW 1454 undef $SIG_TW
1363 unless --$SIG_COUNT; 1455 unless --$SIG_COUNT;
1456}
1364 1457
1458our $_sig_name_init; $_sig_name_init = sub {
1459 eval q{ # poor man's autoloading
1460 undef $_sig_name_init;
1461
1462 if (_have_async_interrupt) {
1463 *sig2num = \&Async::Interrupt::sig2num;
1464 *sig2name = \&Async::Interrupt::sig2name;
1465 } else {
1466 require Config;
1467
1468 my %signame2num;
1469 @signame2num{ split ' ', $Config::Config{sig_name} }
1470 = split ' ', $Config::Config{sig_num};
1471
1472 my @signum2name;
1473 @signum2name[values %signame2num] = keys %signame2num;
1474
1475 *sig2num = sub($) {
1476 $_[0] > 0 ? shift : $signame2num{+shift}
1477 };
1478 *sig2name = sub ($) {
1479 $_[0] > 0 ? $signum2name[+shift] : shift
1480 };
1481 }
1482 };
1483 die if $@;
1484};
1485
1486sub sig2num ($) { &$_sig_name_init; &sig2num }
1487sub sig2name($) { &$_sig_name_init; &sig2name }
1488
1489sub signal {
1490 eval q{ # poor man's autoloading {}
1491 # probe for availability of Async::Interrupt
1492 if (_have_async_interrupt) {
1493 warn "AnyEvent: using Async::Interrupt for race-free signal handling.\n" if $VERBOSE >= 8;
1494
1495 $SIGPIPE_R = new Async::Interrupt::EventPipe;
1496 $SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec;
1497
1498 } else {
1499 warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8;
1500
1501 require Fcntl;
1502
1503 if (AnyEvent::WIN32) {
1504 require AnyEvent::Util;
1505
1506 ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
1507 AnyEvent::Util::fh_nonblocking ($SIGPIPE_R, 1) if $SIGPIPE_R;
1508 AnyEvent::Util::fh_nonblocking ($SIGPIPE_W, 1) if $SIGPIPE_W; # just in case
1509 } else {
1510 pipe $SIGPIPE_R, $SIGPIPE_W;
1511 fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R;
1512 fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case
1513
1514 # not strictly required, as $^F is normally 2, but let's make sure...
1515 fcntl $SIGPIPE_R, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;
1516 fcntl $SIGPIPE_W, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;
1517 }
1518
1519 $SIGPIPE_R
1520 or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";
1521
1522 $SIG_IO = AE::io $SIGPIPE_R, 0, \&_signal_exec;
1523 }
1524
1525 *signal = sub {
1526 my (undef, %arg) = @_;
1527
1528 my $signal = uc $arg{signal}
1529 or Carp::croak "required option 'signal' is missing";
1530
1531 if ($HAVE_ASYNC_INTERRUPT) {
1532 # async::interrupt
1533
1534 $signal = sig2num $signal;
1535 $SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1536
1537 $SIG_ASY{$signal} ||= new Async::Interrupt
1538 cb => sub { undef $SIG_EV{$signal} },
1539 signal => $signal,
1540 pipe => [$SIGPIPE_R->filenos],
1541 pipe_autodrain => 0,
1542 ;
1543
1544 } else {
1545 # pure perl
1546
1547 # AE::Util has been loaded in signal
1548 $signal = sig2name $signal;
1549 $SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1550
1551 $SIG{$signal} ||= sub {
1552 local $!;
1553 syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;
1554 undef $SIG_EV{$signal};
1555 };
1556
1557 # can't do signal processing without introducing races in pure perl,
1558 # so limit the signal latency.
1559 _sig_add;
1560 }
1561
1562 bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
1563 };
1564
1565 *AnyEvent::Base::signal::DESTROY = sub {
1566 my ($signal, $cb) = @{$_[0]};
1567
1568 _sig_del;
1569
1365 delete $SIG_CB{$signal}{$cb}; 1570 delete $SIG_CB{$signal}{$cb};
1366 1571
1572 $HAVE_ASYNC_INTERRUPT
1573 ? delete $SIG_ASY{$signal}
1367 # delete doesn't work with older perls - they then 1574 : # delete doesn't work with older perls - they then
1368 # print weird messages, or just unconditionally exit 1575 # print weird messages, or just unconditionally exit
1369 # instead of getting the default action. 1576 # instead of getting the default action.
1370 undef $SIG{$signal} 1577 undef $SIG{$signal}
1371 unless keys %{ $SIG_CB{$signal} }; 1578 unless keys %{ $SIG_CB{$signal} };
1579 };
1580 };
1581 die if $@;
1582 &signal
1372} 1583}
1373 1584
1374# default implementation for ->child 1585# default implementation for ->child
1375 1586
1376our %PID_CB; 1587our %PID_CB;
1377our $CHLD_W; 1588our $CHLD_W;
1378our $CHLD_DELAY_W; 1589our $CHLD_DELAY_W;
1379our $WNOHANG; 1590our $WNOHANG;
1380 1591
1592sub _emit_childstatus($$) {
1593 my (undef, $rpid, $rstatus) = @_;
1594
1595 $_->($rpid, $rstatus)
1596 for values %{ $PID_CB{$rpid} || {} },
1597 values %{ $PID_CB{0} || {} };
1598}
1599
1381sub _sigchld { 1600sub _sigchld {
1601 my $pid;
1602
1603 AnyEvent->_emit_childstatus ($pid, $?)
1382 while (0 < (my $pid = waitpid -1, $WNOHANG)) { 1604 while ($pid = waitpid -1, $WNOHANG) > 0;
1383 $_->($pid, $?)
1384 for values %{ $PID_CB{$pid} || {} },
1385 values %{ $PID_CB{0} || {} };
1386 }
1387} 1605}
1388 1606
1389sub child { 1607sub child {
1390 my (undef, %arg) = @_; 1608 my (undef, %arg) = @_;
1391 1609
1398 $WNOHANG ||= $^O =~ /^(?:openbsd|netbsd|linux|freebsd|cygwin|MSWin32)$/ 1616 $WNOHANG ||= $^O =~ /^(?:openbsd|netbsd|linux|freebsd|cygwin|MSWin32)$/
1399 ? 1 1617 ? 1
1400 : eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1; 1618 : eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1;
1401 1619
1402 unless ($CHLD_W) { 1620 unless ($CHLD_W) {
1403 $CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld); 1621 $CHLD_W = AE::signal CHLD => \&_sigchld;
1404 # child could be a zombie already, so make at least one round 1622 # child could be a zombie already, so make at least one round
1405 &_sigchld; 1623 &_sigchld;
1406 } 1624 }
1407 1625
1408 bless [$pid, $arg{cb}], "AnyEvent::Base::child" 1626 bless [$pid, $arg{cb}], "AnyEvent::Base::child"
1434 # never use more then 50% of the time for the idle watcher, 1652 # never use more then 50% of the time for the idle watcher,
1435 # within some limits 1653 # within some limits
1436 $w = 0.0001 if $w < 0.0001; 1654 $w = 0.0001 if $w < 0.0001;
1437 $w = 5 if $w > 5; 1655 $w = 5 if $w > 5;
1438 1656
1439 $w = AnyEvent->timer (after => $w, cb => $rcb); 1657 $w = AE::timer $w, 0, $rcb;
1440 } else { 1658 } else {
1441 # clean up... 1659 # clean up...
1442 undef $w; 1660 undef $w;
1443 undef $rcb; 1661 undef $rcb;
1444 } 1662 }
1445 }; 1663 };
1446 1664
1447 $w = AnyEvent->timer (after => 0.05, cb => $rcb); 1665 $w = AE::timer 0.05, 0, $rcb;
1448 1666
1449 bless \\$cb, "AnyEvent::Base::idle" 1667 bless \\$cb, "AnyEvent::Base::idle"
1450} 1668}
1451 1669
1452sub AnyEvent::Base::idle::DESTROY { 1670sub AnyEvent::Base::idle::DESTROY {
1506 Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak}; 1724 Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak};
1507 wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0] 1725 wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0]
1508} 1726}
1509 1727
1510sub cb { 1728sub cb {
1511 $_[0]{_ae_cb} = $_[1] if @_ > 1; 1729 my $cv = shift;
1730
1731 @_
1732 and $cv->{_ae_cb} = shift
1733 and $cv->{_ae_sent}
1734 and (delete $cv->{_ae_cb})->($cv);
1735
1512 $_[0]{_ae_cb} 1736 $cv->{_ae_cb}
1513} 1737}
1514 1738
1515sub begin { 1739sub begin {
1516 ++$_[0]{_ae_counter}; 1740 ++$_[0]{_ae_counter};
1517 $_[0]{_ae_end_cb} = $_[1] if @_ > 1; 1741 $_[0]{_ae_end_cb} = $_[1] if @_ > 1;
1726 warn "read: $input\n"; # output what has been read 1950 warn "read: $input\n"; # output what has been read
1727 $cv->send if $input =~ /^q/i; # quit program if /^q/i 1951 $cv->send if $input =~ /^q/i; # quit program if /^q/i
1728 }, 1952 },
1729 ); 1953 );
1730 1954
1731 my $time_watcher; # can only be used once
1732
1733 sub new_timer {
1734 $timer = AnyEvent->timer (after => 1, cb => sub { 1955 my $time_watcher = AnyEvent->timer (after => 1, interval => 1, cb => sub {
1735 warn "timeout\n"; # print 'timeout' about every second 1956 warn "timeout\n"; # print 'timeout' at most every second
1736 &new_timer; # and restart the time
1737 }); 1957 });
1738 }
1739
1740 new_timer; # create first timer
1741 1958
1742 $cv->recv; # wait until user enters /^q/i 1959 $cv->recv; # wait until user enters /^q/i
1743 1960
1744=head1 REAL-WORLD EXAMPLE 1961=head1 REAL-WORLD EXAMPLE
1745 1962
1876through AnyEvent. The benchmark creates a lot of timers (with a zero 2093through AnyEvent. The benchmark creates a lot of timers (with a zero
1877timeout) and I/O watchers (watching STDOUT, a pty, to become writable, 2094timeout) and I/O watchers (watching STDOUT, a pty, to become writable,
1878which it is), lets them fire exactly once and destroys them again. 2095which it is), lets them fire exactly once and destroys them again.
1879 2096
1880Source code for this benchmark is found as F<eg/bench> in the AnyEvent 2097Source code for this benchmark is found as F<eg/bench> in the AnyEvent
1881distribution. 2098distribution. It uses the L<AE> interface, which makes a real difference
2099for the EV and Perl backends only.
1882 2100
1883=head3 Explanation of the columns 2101=head3 Explanation of the columns
1884 2102
1885I<watcher> is the number of event watchers created/destroyed. Since 2103I<watcher> is the number of event watchers created/destroyed. Since
1886different event models feature vastly different performances, each event 2104different event models feature vastly different performances, each event
1907watcher. 2125watcher.
1908 2126
1909=head3 Results 2127=head3 Results
1910 2128
1911 name watchers bytes create invoke destroy comment 2129 name watchers bytes create invoke destroy comment
1912 EV/EV 400000 224 0.47 0.35 0.27 EV native interface 2130 EV/EV 100000 223 0.47 0.43 0.27 EV native interface
1913 EV/Any 100000 224 2.88 0.34 0.27 EV + AnyEvent watchers 2131 EV/Any 100000 223 0.48 0.42 0.26 EV + AnyEvent watchers
1914 CoroEV/Any 100000 224 2.85 0.35 0.28 coroutines + Coro::Signal 2132 Coro::EV/Any 100000 223 0.47 0.42 0.26 coroutines + Coro::Signal
1915 Perl/Any 100000 452 4.13 0.73 0.95 pure perl implementation 2133 Perl/Any 100000 431 2.70 0.74 0.92 pure perl implementation
1916 Event/Event 16000 517 32.20 31.80 0.81 Event native interface 2134 Event/Event 16000 516 31.16 31.84 0.82 Event native interface
1917 Event/Any 16000 590 35.85 31.55 1.06 Event + AnyEvent watchers 2135 Event/Any 16000 1203 42.61 34.79 1.80 Event + AnyEvent watchers
1918 IOAsync/Any 16000 989 38.10 32.77 11.13 via IO::Async::Loop::IO_Poll 2136 IOAsync/Any 16000 1911 41.92 27.45 16.81 via IO::Async::Loop::IO_Poll
1919 IOAsync/Any 16000 990 37.59 29.50 10.61 via IO::Async::Loop::Epoll 2137 IOAsync/Any 16000 1726 40.69 26.37 15.25 via IO::Async::Loop::Epoll
1920 Glib/Any 16000 1357 102.33 12.31 51.00 quadratic behaviour 2138 Glib/Any 16000 1118 89.00 12.57 51.17 quadratic behaviour
1921 Tk/Any 2000 1860 27.20 66.31 14.00 SEGV with >> 2000 watchers 2139 Tk/Any 2000 1346 20.96 10.75 8.00 SEGV with >> 2000 watchers
1922 POE/Event 2000 6328 109.99 751.67 14.02 via POE::Loop::Event 2140 POE/Any 2000 6951 108.97 795.32 14.24 via POE::Loop::Event
1923 POE/Select 2000 6027 94.54 809.13 579.80 via POE::Loop::Select 2141 POE/Any 2000 6648 94.79 774.40 575.51 via POE::Loop::Select
1924 2142
1925=head3 Discussion 2143=head3 Discussion
1926 2144
1927The benchmark does I<not> measure scalability of the event loop very 2145The benchmark does I<not> measure scalability of the event loop very
1928well. For example, a select-based event loop (such as the pure perl one) 2146well. For example, a select-based event loop (such as the pure perl one)
1940benchmark machine, handling an event takes roughly 1600 CPU cycles with 2158benchmark machine, handling an event takes roughly 1600 CPU cycles with
1941EV, 3100 CPU cycles with AnyEvent's pure perl loop and almost 3000000 CPU 2159EV, 3100 CPU cycles with AnyEvent's pure perl loop and almost 3000000 CPU
1942cycles with POE. 2160cycles with POE.
1943 2161
1944C<EV> is the sole leader regarding speed and memory use, which are both 2162C<EV> is the sole leader regarding speed and memory use, which are both
1945maximal/minimal, respectively. Even when going through AnyEvent, it uses 2163maximal/minimal, respectively. When using the L<AE> API there is zero
2164overhead (when going through the AnyEvent API create is about 5-6 times
2165slower, with other times being equal, so still uses far less memory than
1946far less memory than any other event loop and is still faster than Event 2166any other event loop and is still faster than Event natively).
1947natively.
1948 2167
1949The pure perl implementation is hit in a few sweet spots (both the 2168The pure perl implementation is hit in a few sweet spots (both the
1950constant timeout and the use of a single fd hit optimisations in the perl 2169constant timeout and the use of a single fd hit optimisations in the perl
1951interpreter and the backend itself). Nevertheless this shows that it 2170interpreter and the backend itself). Nevertheless this shows that it
1952adds very little overhead in itself. Like any select-based backend its 2171adds very little overhead in itself. Like any select-based backend its
2026In this benchmark, we use 10000 socket pairs (20000 sockets), of which 100 2245In this benchmark, we use 10000 socket pairs (20000 sockets), of which 100
2027(1%) are active. This mirrors the activity of large servers with many 2246(1%) are active. This mirrors the activity of large servers with many
2028connections, most of which are idle at any one point in time. 2247connections, most of which are idle at any one point in time.
2029 2248
2030Source code for this benchmark is found as F<eg/bench2> in the AnyEvent 2249Source code for this benchmark is found as F<eg/bench2> in the AnyEvent
2031distribution. 2250distribution. It uses the L<AE> interface, which makes a real difference
2251for the EV and Perl backends only.
2032 2252
2033=head3 Explanation of the columns 2253=head3 Explanation of the columns
2034 2254
2035I<sockets> is the number of sockets, and twice the number of "servers" (as 2255I<sockets> is the number of sockets, and twice the number of "servers" (as
2036each server has a read and write socket end). 2256each server has a read and write socket end).
2044a new one that moves the timeout into the future. 2264a new one that moves the timeout into the future.
2045 2265
2046=head3 Results 2266=head3 Results
2047 2267
2048 name sockets create request 2268 name sockets create request
2049 EV 20000 69.01 11.16 2269 EV 20000 62.66 7.99
2050 Perl 20000 73.32 35.87 2270 Perl 20000 68.32 32.64
2051 IOAsync 20000 157.00 98.14 epoll 2271 IOAsync 20000 174.06 101.15 epoll
2052 IOAsync 20000 159.31 616.06 poll 2272 IOAsync 20000 174.67 610.84 poll
2053 Event 20000 212.62 257.32 2273 Event 20000 202.69 242.91
2054 Glib 20000 651.16 1896.30 2274 Glib 20000 557.01 1689.52
2055 POE 20000 349.67 12317.24 uses POE::Loop::Event 2275 POE 20000 341.54 12086.32 uses POE::Loop::Event
2056 2276
2057=head3 Discussion 2277=head3 Discussion
2058 2278
2059This benchmark I<does> measure scalability and overall performance of the 2279This benchmark I<does> measure scalability and overall performance of the
2060particular event loop. 2280particular event loop.
2186As you can see, the AnyEvent + EV combination even beats the 2406As you can see, the AnyEvent + EV combination even beats the
2187hand-optimised "raw sockets benchmark", while AnyEvent + its pure perl 2407hand-optimised "raw sockets benchmark", while AnyEvent + its pure perl
2188backend easily beats IO::Lambda and POE. 2408backend easily beats IO::Lambda and POE.
2189 2409
2190And even the 100% non-blocking version written using the high-level (and 2410And even the 100% non-blocking version written using the high-level (and
2191slow :) L<AnyEvent::Handle> abstraction beats both POE and IO::Lambda by a 2411slow :) L<AnyEvent::Handle> abstraction beats both POE and IO::Lambda
2192large margin, even though it does all of DNS, tcp-connect and socket I/O 2412higher level ("unoptimised") abstractions by a large margin, even though
2193in a non-blocking way. 2413it does all of DNS, tcp-connect and socket I/O in a non-blocking way.
2194 2414
2195The two AnyEvent benchmarks programs can be found as F<eg/ae0.pl> and 2415The two AnyEvent benchmarks programs can be found as F<eg/ae0.pl> and
2196F<eg/ae2.pl> in the AnyEvent distribution, the remaining benchmarks are 2416F<eg/ae2.pl> in the AnyEvent distribution, the remaining benchmarks are
2197part of the IO::lambda distribution and were used without any changes. 2417part of the IO::Lambda distribution and were used without any changes.
2198 2418
2199 2419
2200=head1 SIGNALS 2420=head1 SIGNALS
2201 2421
2202AnyEvent currently installs handlers for these signals: 2422AnyEvent currently installs handlers for these signals:
2244it's built-in modules) are required to use it. 2464it's built-in modules) are required to use it.
2245 2465
2246That does not mean that AnyEvent won't take advantage of some additional 2466That does not mean that AnyEvent won't take advantage of some additional
2247modules if they are installed. 2467modules if they are installed.
2248 2468
2249This section epxlains which additional modules will be used, and how they 2469This section explains which additional modules will be used, and how they
2250affect AnyEvent's operetion. 2470affect AnyEvent's operation.
2251 2471
2252=over 4 2472=over 4
2253 2473
2254=item L<Async::Interrupt> 2474=item L<Async::Interrupt>
2255 2475
2256This slightly arcane module is used to implement fast signal handling: To 2476This slightly arcane module is used to implement fast signal handling: To
2257my knowledge, there is no way to do completely race-free and quick 2477my knowledge, there is no way to do completely race-free and quick
2258signal handling in pure perl. To ensure that signals still get 2478signal handling in pure perl. To ensure that signals still get
2259delivered, AnyEvent will start an interval timer to wake up perl (and 2479delivered, AnyEvent will start an interval timer to wake up perl (and
2260catch the signals) with soemd elay (default is 10 seconds, look for 2480catch the signals) with some delay (default is 10 seconds, look for
2261C<$AnyEvent::MAX_SIGNAL_LATENCY>). 2481C<$AnyEvent::MAX_SIGNAL_LATENCY>).
2262 2482
2263If this module is available, then it will be used to implement signal 2483If this module is available, then it will be used to implement signal
2264catching, which means that signals will not be delayed, and the event loop 2484catching, which means that signals will not be delayed, and the event loop
2265will not be interrupted regularly, which is more efficient (And good for 2485will not be interrupted regularly, which is more efficient (and good for
2266battery life on laptops). 2486battery life on laptops).
2267 2487
2268This affects not just the pure-perl event loop, but also other event loops 2488This affects not just the pure-perl event loop, but also other event loops
2269that have no signal handling on their own (e.g. Glib, Tk, Qt). 2489that have no signal handling on their own (e.g. Glib, Tk, Qt).
2490
2491Some event loops (POE, Event, Event::Lib) offer signal watchers natively,
2492and either employ their own workarounds (POE) or use AnyEvent's workaround
2493(using C<$AnyEvent::MAX_SIGNAL_LATENCY>). Installing L<Async::Interrupt>
2494does nothing for those backends.
2270 2495
2271=item L<EV> 2496=item L<EV>
2272 2497
2273This module isn't really "optional", as it is simply one of the backend 2498This module isn't really "optional", as it is simply one of the backend
2274event loops that AnyEvent can use. However, it is simply the best event 2499event loops that AnyEvent can use. However, it is simply the best event
2286lot less memory), but otherwise doesn't affect guard operation much. It is 2511lot less memory), but otherwise doesn't affect guard operation much. It is
2287purely used for performance. 2512purely used for performance.
2288 2513
2289=item L<JSON> and L<JSON::XS> 2514=item L<JSON> and L<JSON::XS>
2290 2515
2291This module is required when you want to read or write JSON data via 2516One of these modules is required when you want to read or write JSON data
2292L<AnyEvent::Handle>. It is also written in pure-perl, but can take 2517via L<AnyEvent::Handle>. It is also written in pure-perl, but can take
2293advantage of the ulta-high-speed L<JSON::XS> module when it is installed. 2518advantage of the ultra-high-speed L<JSON::XS> module when it is installed.
2294 2519
2295In fact, L<AnyEvent::Handle> will use L<JSON::XS> by default if it is 2520In fact, L<AnyEvent::Handle> will use L<JSON::XS> by default if it is
2296installed. 2521installed.
2297 2522
2298=item L<Net::SSLeay> 2523=item L<Net::SSLeay>
2312 2537
2313 2538
2314=head1 FORK 2539=head1 FORK
2315 2540
2316Most event libraries are not fork-safe. The ones who are usually are 2541Most event libraries are not fork-safe. The ones who are usually are
2317because they rely on inefficient but fork-safe C<select> or C<poll> 2542because they rely on inefficient but fork-safe C<select> or C<poll> calls
2318calls. Only L<EV> is fully fork-aware. 2543- higher performance APIs such as BSD's kqueue or the dreaded Linux epoll
2544are usually badly thought-out hacks that are incompatible with fork in
2545one way or another. Only L<EV> is fully fork-aware and ensures that you
2546continue event-processing in both parent and child (or both, if you know
2547what you are doing).
2548
2549This means that, in general, you cannot fork and do event processing in
2550the child if the event library was initialised before the fork (which
2551usually happens when the first AnyEvent watcher is created, or the library
2552is loaded).
2319 2553
2320If you have to fork, you must either do so I<before> creating your first 2554If you have to fork, you must either do so I<before> creating your first
2321watcher OR you must not use AnyEvent at all in the child OR you must do 2555watcher OR you must not use AnyEvent at all in the child OR you must do
2322something completely out of the scope of AnyEvent. 2556something completely out of the scope of AnyEvent.
2557
2558The problem of doing event processing in the parent I<and> the child
2559is much more complicated: even for backends that I<are> fork-aware or
2560fork-safe, their behaviour is not usually what you want: fork clones all
2561watchers, that means all timers, I/O watchers etc. are active in both
2562parent and child, which is almost never what you want. USing C<exec>
2563to start worker children from some kind of manage rprocess is usually
2564preferred, because it is much easier and cleaner, at the expense of having
2565to have another binary.
2323 2566
2324 2567
2325=head1 SECURITY CONSIDERATIONS 2568=head1 SECURITY CONSIDERATIONS
2326 2569
2327AnyEvent can be forced to load any event model via 2570AnyEvent can be forced to load any event model via
2365L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>. 2608L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>.
2366 2609
2367Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>, 2610Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>,
2368L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>, 2611L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>,
2369L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>, 2612L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>,
2370L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>. 2613L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>, L<Anyevent::Impl::Irssi>.
2371 2614
2372Non-blocking file handles, sockets, TCP clients and 2615Non-blocking file handles, sockets, TCP clients and
2373servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>. 2616servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>.
2374 2617
2375Asynchronous DNS: L<AnyEvent::DNS>. 2618Asynchronous DNS: L<AnyEvent::DNS>.

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