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Revision 1.311 by root, Wed Feb 10 13:33:44 2010 UTC

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
372 403
373Example: exit on SIGINT 404Example: exit on SIGINT
374 405
375 my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 }); 406 my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });
376 407
408=head3 Restart Behaviour
409
410While restart behaviour is up to the event loop implementation, most will
411not restart syscalls (that includes L<Async::Interrupt> and AnyEvent's
412pure perl implementation).
413
414=head3 Safe/Unsafe Signals
415
416Perl signals can be either "safe" (synchronous to opcode handling) or
417"unsafe" (asynchronous) - the former might get delayed indefinitely, the
418latter might corrupt your memory.
419
420AnyEvent signal handlers are, in addition, synchronous to the event loop,
421i.e. they will not interrupt your running perl program but will only be
422called as part of the normal event handling (just like timer, I/O etc.
423callbacks, too).
424
377=head3 Signal Races, Delays and Workarounds 425=head3 Signal Races, Delays and Workarounds
378 426
379Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching 427Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching
380callbacks to signals in a generic way, which is a pity, as you cannot do 428callbacks to signals in a generic way, which is a pity, as you cannot
381race-free signal handling in perl. AnyEvent will try to do it's best, but 429do race-free signal handling in perl, requiring C libraries for
430this. AnyEvent will try to do it's best, which means in some cases,
382in some cases, signals will be delayed. The maximum time a signal might 431signals will be delayed. The maximum time a signal might be delayed is
383be delayed is specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 432specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 seconds). This
384seconds). This variable can be changed only before the first signal 433variable can be changed only before the first signal watcher is created,
385watcher 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
386will 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
387saving. All these problems can be avoided by installing the optional 439All these problems can be avoided by installing the optional
388L<Async::Interrupt> module. This will not work with inherently broken 440L<Async::Interrupt> module, which works with most event loops. It will not
389event loops such as L<Event> or L<Event::Lib> (and not with L<POE> 441work with inherently broken event loops such as L<Event> or L<Event::Lib>
390currently, as POE does it's own workaround with one-second latency). With 442(and not with L<POE> currently, as POE does it's own workaround with
391those, you just have to suffer the delays. 443one-second latency). For those, you just have to suffer the delays.
392 444
393=head2 CHILD PROCESS WATCHERS 445=head2 CHILD PROCESS WATCHERS
394 446
447 $w = AnyEvent->child (pid => <process id>, cb => <callback>);
448
395You 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.
396 450
397The 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,
398watches for any child process exit). The watcher will triggered only when 452using C<0> watches for any child process exit, on others this will
399the child process has finished and an exit status is available, not on 453croak). The watcher will be triggered only when the child process has
400any trace events (stopped/continued). 454finished and an exit status is available, not on any trace events
455(stopped/continued).
401 456
402The 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
403waitpid), 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
404callback arguments. 459callback arguments.
405 460
446 # do something else, then wait for process exit 501 # do something else, then wait for process exit
447 $done->recv; 502 $done->recv;
448 503
449=head2 IDLE WATCHERS 504=head2 IDLE WATCHERS
450 505
451Sometimes there is a need to do something, but it is not so important 506 $w = AnyEvent->idle (cb => <callback>);
452to do it instantly, but only when there is nothing better to do. This
453"nothing better to do" is usually defined to be "no other events need
454attention by the event loop".
455 507
456Idle watchers ideally get invoked when the event loop has nothing 508Repeatedly invoke the callback after the process becomes idle, until
457better to do, just before it would block the process to wait for new 509either the watcher is destroyed or new events have been detected.
458events. Instead of blocking, the idle watcher is invoked.
459 510
460Most 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
461EV, 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
462will simply call the callback "from time to time". 522will simply call the callback "from time to time".
463 523
464Example: read lines from STDIN, but only process them when the 524Example: read lines from STDIN, but only process them when the
465program is otherwise idle: 525program is otherwise idle:
481 }); 541 });
482 }); 542 });
483 543
484=head2 CONDITION VARIABLES 544=head2 CONDITION VARIABLES
485 545
546 $cv = AnyEvent->condvar;
547
548 $cv->send (<list>);
549 my @res = $cv->recv;
550
486If 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
487require you to run some blocking "loop", "run" or similar function that 552require you to run some blocking "loop", "run" or similar function that
488will actively watch for new events and call your callbacks. 553will actively watch for new events and call your callbacks.
489 554
490AnyEvent is slightly different: it expects somebody else to run the event 555AnyEvent is slightly different: it expects somebody else to run the event
509Condition variables are similar to callbacks, except that you can 574Condition variables are similar to callbacks, except that you can
510optionally wait for them. They can also be called merge points - points 575optionally wait for them. They can also be called merge points - points
511in time where multiple outstanding events have been processed. And yet 576in time where multiple outstanding events have been processed. And yet
512another way to call them is transactions - each condition variable can be 577another way to call them is transactions - each condition variable can be
513used to represent a transaction, which finishes at some point and delivers 578used to represent a transaction, which finishes at some point and delivers
514a result. 579a result. And yet some people know them as "futures" - a promise to
580compute/deliver something that you can wait for.
515 581
516Condition variables are very useful to signal that something has finished, 582Condition variables are very useful to signal that something has finished,
517for example, if you write a module that does asynchronous http requests, 583for example, if you write a module that does asynchronous http requests,
518then a condition variable would be the ideal candidate to signal the 584then a condition variable would be the ideal candidate to signal the
519availability of results. The user can either act when the callback is 585availability of results. The user can either act when the callback is
553 after => 1, 619 after => 1,
554 cb => sub { $result_ready->send }, 620 cb => sub { $result_ready->send },
555 ); 621 );
556 622
557 # this "blocks" (while handling events) till the callback 623 # this "blocks" (while handling events) till the callback
558 # calls -<send 624 # calls ->send
559 $result_ready->recv; 625 $result_ready->recv;
560 626
561Example: 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
562variables are also callable directly. 628variables are also callable directly.
563 629
627one. 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
628to use a condition variable for the whole process. 694to use a condition variable for the whole process.
629 695
630Every 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
631C<< ->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
632>>, 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
633is 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
634callback 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.
635 702
636You 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
637sends), 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
638condition (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).
639 706
666begung can potentially be zero: 733begung can potentially be zero:
667 734
668 my $cv = AnyEvent->condvar; 735 my $cv = AnyEvent->condvar;
669 736
670 my %result; 737 my %result;
671 $cv->begin (sub { $cv->send (\%result) }); 738 $cv->begin (sub { shift->send (\%result) });
672 739
673 for my $host (@list_of_hosts) { 740 for my $host (@list_of_hosts) {
674 $cv->begin; 741 $cv->begin;
675 ping_host_then_call_callback $host, sub { 742 ping_host_then_call_callback $host, sub {
676 $result{$host} = ...; 743 $result{$host} = ...;
751=item $cb = $cv->cb ($cb->($cv)) 818=item $cb = $cv->cb ($cb->($cv))
752 819
753This is a mutator function that returns the callback set and optionally 820This is a mutator function that returns the callback set and optionally
754replaces it before doing so. 821replaces it before doing so.
755 822
756The callback will be called when the condition becomes "true", i.e. when 823The callback will be called when the condition becomes (or already was)
757C<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
758variable itself. Calling C<recv> inside the callback or at any later time 825the only argument being the condition variable itself. Calling C<recv>
759is guaranteed not to block. 826inside the callback or at any later time is guaranteed not to block.
760 827
761=back 828=back
762 829
763=head1 SUPPORTED EVENT LOOPS/BACKENDS 830=head1 SUPPORTED EVENT LOOPS/BACKENDS
764 831
767=over 4 834=over 4
768 835
769=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.
770 837
771EV 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
772use. 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
773that, will fall back to its own pure-perl implementation, which is 840pure-perl implementation, which is available everywhere as it comes with
774available everywhere as it comes with AnyEvent itself. 841AnyEvent itself.
775 842
776 AnyEvent::Impl::EV based on EV (interface to libev, best choice). 843 AnyEvent::Impl::EV based on EV (interface to libev, best choice).
777 AnyEvent::Impl::Event based on Event, very stable, few glitches.
778 AnyEvent::Impl::Perl pure-perl implementation, fast and portable. 844 AnyEvent::Impl::Perl pure-perl implementation, fast and portable.
779 845
780=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.
781 847
782These 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
783is 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
784them. This means that AnyEvent will automatically pick the right backend 850them. This means that AnyEvent will automatically pick the right backend
785when the main program loads an event module before anything starts to 851when the main program loads an event module before anything starts to
786create watchers. Nothing special needs to be done by the main program. 852create watchers. Nothing special needs to be done by the main program.
787 853
854 AnyEvent::Impl::Event based on Event, very stable, few glitches.
788 AnyEvent::Impl::Glib based on Glib, slow but very stable. 855 AnyEvent::Impl::Glib based on Glib, slow but very stable.
789 AnyEvent::Impl::Tk based on Tk, very broken. 856 AnyEvent::Impl::Tk based on Tk, very broken.
790 AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse. 857 AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.
791 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.
792 860
793=item Backends with special needs. 861=item Backends with special needs.
794 862
795Qt requires the Qt::Application to be instantiated first, but will 863Qt requires the Qt::Application to be instantiated first, but will
796otherwise be picked up automatically. As long as the main program 864otherwise be picked up automatically. As long as the main program
870event module detection too early, for example, L<AnyEvent::AIO> creates 938event module detection too early, for example, L<AnyEvent::AIO> creates
871and 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
872avoid autodetecting the event module at load time. 940avoid autodetecting the event module at load time.
873 941
874If 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
875that 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
876L<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 ||= $guard;
877 962
878=item @AnyEvent::post_detect 963=item @AnyEvent::post_detect
879 964
880If there are any code references in this array (you can C<push> to it 965If there are any code references in this array (you can C<push> to it
881before or after loading AnyEvent), then they will called directly after 966before or after loading AnyEvent), then they will called directly after
884You should check C<$AnyEvent::MODEL> before adding to this array, though: 969You should check C<$AnyEvent::MODEL> before adding to this array, though:
885if 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
886array will be ignored. 971array will be ignored.
887 972
888Best use C<AnyEvent::post_detect { BLOCK }> when your application allows 973Best use C<AnyEvent::post_detect { BLOCK }> when your application allows
889it,as it takes care of these details. 974it, as it takes care of these details.
890 975
891This variable is mainly useful for modules that can do something useful 976This variable is mainly useful for modules that can do something useful
892when 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
893not 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
894into 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 }
895 993
896=back 994=back
897 995
898=head1 WHAT TO DO IN A MODULE 996=head1 WHAT TO DO IN A MODULE
899 997
1048 1146
1049package AnyEvent; 1147package AnyEvent;
1050 1148
1051# basically a tuned-down version of common::sense 1149# basically a tuned-down version of common::sense
1052sub common_sense { 1150sub common_sense {
1053 # no warnings 1151 # from common:.sense 1.0
1054 ${^WARNING_BITS} ^= ${^WARNING_BITS}; 1152 ${^WARNING_BITS} = "\xfc\x3f\x33\x00\x0f\xf3\xcf\xc0\xf3\xfc\x33\x00";
1055 # use strict vars subs 1153 # use strict vars subs - NO UTF-8, as Util.pm doesn't like this atm. (uts46data.pl)
1056 $^H |= 0x00000600; 1154 $^H |= 0x00000600;
1057} 1155}
1058 1156
1059BEGIN { AnyEvent::common_sense } 1157BEGIN { AnyEvent::common_sense }
1060 1158
1061use Carp (); 1159use Carp ();
1062 1160
1063our $VERSION = 4.85; 1161our $VERSION = '5.24';
1064our $MODEL; 1162our $MODEL;
1065 1163
1066our $AUTOLOAD; 1164our $AUTOLOAD;
1067our @ISA; 1165our @ISA;
1068 1166
1069our @REGISTRY; 1167our @REGISTRY;
1070 1168
1071our $WIN32;
1072
1073our $VERBOSE; 1169our $VERBOSE;
1074 1170
1075BEGIN { 1171BEGIN {
1172 eval "sub CYGWIN(){" . (($^O =~ /cygwin/i) *1) . "}";
1076 eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }"; 1173 eval "sub WIN32 (){" . (($^O =~ /mswin32/i)*1) . "}";
1077 eval "sub TAINT(){ " . (${^TAINT}*1) . " }"; 1174 eval "sub TAINT (){" . (${^TAINT} *1) . "}";
1078 1175
1079 delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV} 1176 delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}
1080 if ${^TAINT}; 1177 if ${^TAINT};
1081 1178
1082 $VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1; 1179 $VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1;
1093 for reverse split /\s*,\s*/, 1190 for reverse split /\s*,\s*/,
1094 $ENV{PERL_ANYEVENT_PROTOCOLS} || "ipv4,ipv6"; 1191 $ENV{PERL_ANYEVENT_PROTOCOLS} || "ipv4,ipv6";
1095} 1192}
1096 1193
1097my @models = ( 1194my @models = (
1098 [EV:: => AnyEvent::Impl::EV::], 1195 [EV:: => AnyEvent::Impl::EV:: , 1],
1099 [Event:: => AnyEvent::Impl::Event::],
1100 [AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl::], 1196 [AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl:: , 1],
1101 # everything below here will not be autoprobed 1197 # everything below here will not (normally) be autoprobed
1102 # as the pureperl backend should work everywhere 1198 # as the pureperl backend should work everywhere
1103 # and is usually faster 1199 # and is usually faster
1200 [Event:: => AnyEvent::Impl::Event::, 1],
1104 [Glib:: => AnyEvent::Impl::Glib::], # becomes extremely slow with many watchers 1201 [Glib:: => AnyEvent::Impl::Glib:: , 1], # becomes extremely slow with many watchers
1105 [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy 1202 [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy
1203 [Irssi:: => AnyEvent::Impl::Irssi::], # Irssi has a bogus "Event" package
1106 [Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles 1204 [Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles
1107 [Qt:: => AnyEvent::Impl::Qt::], # requires special main program 1205 [Qt:: => AnyEvent::Impl::Qt::], # requires special main program
1108 [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza 1206 [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza
1109 [Wx:: => AnyEvent::Impl::POE::], 1207 [Wx:: => AnyEvent::Impl::POE::],
1110 [Prima:: => AnyEvent::Impl::POE::], 1208 [Prima:: => AnyEvent::Impl::POE::],
1111 # IO::Async is just too broken - we would need workarounds for its 1209 # IO::Async is just too broken - we would need workarounds for its
1112 # byzantine signal and broken child handling, among others. 1210 # byzantine signal and broken child handling, among others.
1113 # IO::Async is rather hard to detect, as it doesn't have any 1211 # IO::Async is rather hard to detect, as it doesn't have any
1114 # obvious default class. 1212 # obvious default class.
1115# [IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program 1213 [IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program
1116# [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program 1214 [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program
1117# [IO::Async::Notifier:: => AnyEvent::Impl::IOAsync::], # requires special main program 1215 [IO::Async::Notifier:: => AnyEvent::Impl::IOAsync::], # requires special main program
1216 [AnyEvent::Impl::IOAsync:: => AnyEvent::Impl::IOAsync::], # requires special main program
1118); 1217);
1119 1218
1120our %method = map +($_ => 1), 1219our %method = map +($_ => 1),
1121 qw(io timer time now now_update signal child idle condvar one_event DESTROY); 1220 qw(io timer time now now_update signal child idle condvar one_event DESTROY);
1122 1221
1126 my ($cb) = @_; 1225 my ($cb) = @_;
1127 1226
1128 if ($MODEL) { 1227 if ($MODEL) {
1129 $cb->(); 1228 $cb->();
1130 1229
1131 1 1230 undef
1132 } else { 1231 } else {
1133 push @post_detect, $cb; 1232 push @post_detect, $cb;
1134 1233
1135 defined wantarray 1234 defined wantarray
1136 ? bless \$cb, "AnyEvent::Util::postdetect" 1235 ? bless \$cb, "AnyEvent::Util::postdetect"
1168 } 1267 }
1169 } 1268 }
1170 } 1269 }
1171 1270
1172 unless ($MODEL) { 1271 unless ($MODEL) {
1173 # try to load a model 1272 # try to autoload a model
1174
1175 for (@REGISTRY, @models) { 1273 for (@REGISTRY, @models) {
1176 my ($package, $model) = @$_; 1274 my ($package, $model, $autoload) = @$_;
1275 if (
1276 $autoload
1177 if (eval "require $package" 1277 and eval "require $package"
1178 and ${"$package\::VERSION"} > 0 1278 and ${"$package\::VERSION"} > 0
1179 and eval "require $model") { 1279 and eval "require $model"
1280 ) {
1180 $MODEL = $model; 1281 $MODEL = $model;
1181 warn "AnyEvent: autoprobed model '$model', using it.\n" if $VERBOSE >= 2; 1282 warn "AnyEvent: autoloaded model '$model', using it.\n" if $VERBOSE >= 2;
1182 last; 1283 last;
1183 } 1284 }
1184 } 1285 }
1185 1286
1186 $MODEL 1287 $MODEL
1227 # we assume CLOEXEC is already set by perl in all important cases 1328 # we assume CLOEXEC is already set by perl in all important cases
1228 1329
1229 ($fh2, $rw) 1330 ($fh2, $rw)
1230} 1331}
1231 1332
1333=head1 SIMPLIFIED AE API
1334
1335Starting with version 5.0, AnyEvent officially supports a second, much
1336simpler, API that is designed to reduce the calling, typing and memory
1337overhead.
1338
1339See the L<AE> manpage for details.
1340
1341=cut
1342
1343package AE;
1344
1345our $VERSION = $AnyEvent::VERSION;
1346
1347sub io($$$) {
1348 AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2])
1349}
1350
1351sub timer($$$) {
1352 AnyEvent->timer (after => $_[0], interval => $_[1], cb => $_[2])
1353}
1354
1355sub signal($$) {
1356 AnyEvent->signal (signal => $_[0], cb => $_[1])
1357}
1358
1359sub child($$) {
1360 AnyEvent->child (pid => $_[0], cb => $_[1])
1361}
1362
1363sub idle($) {
1364 AnyEvent->idle (cb => $_[0])
1365}
1366
1367sub cv(;&) {
1368 AnyEvent->condvar (@_ ? (cb => $_[0]) : ())
1369}
1370
1371sub now() {
1372 AnyEvent->now
1373}
1374
1375sub now_update() {
1376 AnyEvent->now_update
1377}
1378
1379sub time() {
1380 AnyEvent->time
1381}
1382
1232package AnyEvent::Base; 1383package AnyEvent::Base;
1233 1384
1234# default implementations for many methods 1385# default implementations for many methods
1235 1386
1236sub _time { 1387sub _time() {
1237 # probe for availability of Time::HiRes 1388 # probe for availability of Time::HiRes
1238 if (eval "use Time::HiRes (); Time::HiRes::time (); 1") { 1389 if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {
1239 warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8; 1390 warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8;
1240 *_time = \&Time::HiRes::time; 1391 *_time = \&Time::HiRes::time;
1241 # if (eval "use POSIX (); (POSIX::times())... 1392 # if (eval "use POSIX (); (POSIX::times())...
1242 } else { 1393 } else {
1243 warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE; 1394 warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE;
1244 *_time = sub { time }; # epic fail 1395 *_time = sub (){ time }; # epic fail
1245 } 1396 }
1246 1397
1247 &_time 1398 &_time
1248} 1399}
1249 1400
1258} 1409}
1259 1410
1260# default implementation for ->signal 1411# default implementation for ->signal
1261 1412
1262our $HAVE_ASYNC_INTERRUPT; 1413our $HAVE_ASYNC_INTERRUPT;
1414
1415sub _have_async_interrupt() {
1416 $HAVE_ASYNC_INTERRUPT = 1*(!$ENV{PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT}
1417 && eval "use Async::Interrupt 1.02 (); 1")
1418 unless defined $HAVE_ASYNC_INTERRUPT;
1419
1420 $HAVE_ASYNC_INTERRUPT
1421}
1422
1263our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO); 1423our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO);
1264our (%SIG_ASY, %SIG_ASY_W); 1424our (%SIG_ASY, %SIG_ASY_W);
1265our ($SIG_COUNT, $SIG_TW); 1425our ($SIG_COUNT, $SIG_TW);
1266 1426
1267sub _signal_exec { 1427sub _signal_exec {
1268 $HAVE_ASYNC_INTERRUPT 1428 $HAVE_ASYNC_INTERRUPT
1269 ? $SIGPIPE_R->drain 1429 ? $SIGPIPE_R->drain
1270 : sysread $SIGPIPE_R, my $dummy, 9; 1430 : sysread $SIGPIPE_R, (my $dummy), 9;
1271 1431
1272 while (%SIG_EV) { 1432 while (%SIG_EV) {
1273 for (keys %SIG_EV) { 1433 for (keys %SIG_EV) {
1274 delete $SIG_EV{$_}; 1434 delete $SIG_EV{$_};
1275 $_->() for values %{ $SIG_CB{$_} || {} }; 1435 $_->() for values %{ $SIG_CB{$_} || {} };
1276 } 1436 }
1277 } 1437 }
1278} 1438}
1279 1439
1280# install a dumym wakeupw atcher to reduce signal catching latency 1440# install a dummy wakeup watcher to reduce signal catching latency
1281sub _sig_add() { 1441sub _sig_add() {
1282 unless ($SIG_COUNT++) { 1442 unless ($SIG_COUNT++) {
1283 # try to align timer on a full-second boundary, if possible 1443 # try to align timer on a full-second boundary, if possible
1284 my $NOW = AnyEvent->now; 1444 my $NOW = AE::now;
1285 1445
1286 $SIG_TW = AnyEvent->timer ( 1446 $SIG_TW = AE::timer
1287 after => $MAX_SIGNAL_LATENCY - ($NOW - int $NOW), 1447 $MAX_SIGNAL_LATENCY - ($NOW - int $NOW),
1288 interval => $MAX_SIGNAL_LATENCY, 1448 $MAX_SIGNAL_LATENCY,
1289 cb => sub { }, # just for the PERL_ASYNC_CHECK 1449 sub { } # just for the PERL_ASYNC_CHECK
1290 ); 1450 ;
1291 } 1451 }
1292} 1452}
1293 1453
1294sub _sig_del { 1454sub _sig_del {
1295 undef $SIG_TW 1455 undef $SIG_TW
1296 unless --$SIG_COUNT; 1456 unless --$SIG_COUNT;
1297} 1457}
1298 1458
1459our $_sig_name_init; $_sig_name_init = sub {
1460 eval q{ # poor man's autoloading
1461 undef $_sig_name_init;
1462
1463 if (_have_async_interrupt) {
1464 *sig2num = \&Async::Interrupt::sig2num;
1465 *sig2name = \&Async::Interrupt::sig2name;
1466 } else {
1467 require Config;
1468
1469 my %signame2num;
1470 @signame2num{ split ' ', $Config::Config{sig_name} }
1471 = split ' ', $Config::Config{sig_num};
1472
1473 my @signum2name;
1474 @signum2name[values %signame2num] = keys %signame2num;
1475
1476 *sig2num = sub($) {
1477 $_[0] > 0 ? shift : $signame2num{+shift}
1478 };
1479 *sig2name = sub ($) {
1480 $_[0] > 0 ? $signum2name[+shift] : shift
1481 };
1482 }
1483 };
1484 die if $@;
1485};
1486
1487sub sig2num ($) { &$_sig_name_init; &sig2num }
1488sub sig2name($) { &$_sig_name_init; &sig2name }
1489
1299sub _signal { 1490sub signal {
1491 eval q{ # poor man's autoloading {}
1492 # probe for availability of Async::Interrupt
1493 if (_have_async_interrupt) {
1494 warn "AnyEvent: using Async::Interrupt for race-free signal handling.\n" if $VERBOSE >= 8;
1495
1496 $SIGPIPE_R = new Async::Interrupt::EventPipe;
1497 $SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec;
1498
1499 } else {
1500 warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8;
1501
1502 require Fcntl;
1503
1504 if (AnyEvent::WIN32) {
1505 require AnyEvent::Util;
1506
1507 ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
1508 AnyEvent::Util::fh_nonblocking ($SIGPIPE_R, 1) if $SIGPIPE_R;
1509 AnyEvent::Util::fh_nonblocking ($SIGPIPE_W, 1) if $SIGPIPE_W; # just in case
1510 } else {
1511 pipe $SIGPIPE_R, $SIGPIPE_W;
1512 fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R;
1513 fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case
1514
1515 # not strictly required, as $^F is normally 2, but let's make sure...
1516 fcntl $SIGPIPE_R, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;
1517 fcntl $SIGPIPE_W, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;
1518 }
1519
1520 $SIGPIPE_R
1521 or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";
1522
1523 $SIG_IO = AE::io $SIGPIPE_R, 0, \&_signal_exec;
1524 }
1525
1526 *signal = sub {
1300 my (undef, %arg) = @_; 1527 my (undef, %arg) = @_;
1301 1528
1302 my $signal = uc $arg{signal} 1529 my $signal = uc $arg{signal}
1303 or Carp::croak "required option 'signal' is missing"; 1530 or Carp::croak "required option 'signal' is missing";
1304 1531
1305 $SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1306
1307 if ($HAVE_ASYNC_INTERRUPT) { 1532 if ($HAVE_ASYNC_INTERRUPT) {
1308 # async::interrupt 1533 # async::interrupt
1309 1534
1310 $SIG_ASY{$signal} ||= do { 1535 $signal = sig2num $signal;
1311 my $asy = new Async::Interrupt 1536 $SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1537
1538 $SIG_ASY{$signal} ||= new Async::Interrupt
1312 cb => sub { undef $SIG_EV{$signal} }, 1539 cb => sub { undef $SIG_EV{$signal} },
1313 signal => $signal, 1540 signal => $signal,
1314 pipe => [$SIGPIPE_R->filenos], 1541 pipe => [$SIGPIPE_R->filenos],
1542 pipe_autodrain => 0,
1543 ;
1544
1545 } else {
1546 # pure perl
1547
1548 # AE::Util has been loaded in signal
1549 $signal = sig2name $signal;
1550 $SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1551
1552 $SIG{$signal} ||= sub {
1553 local $!;
1554 syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;
1555 undef $SIG_EV{$signal};
1556 };
1557
1558 # can't do signal processing without introducing races in pure perl,
1559 # so limit the signal latency.
1560 _sig_add;
1315 ; 1561 }
1316 $asy->pipe_autodrain (0);
1317 1562
1318 $asy 1563 bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
1319 }; 1564 };
1320 1565
1321 } else { 1566 *AnyEvent::Base::signal::DESTROY = sub {
1322 # pure perl 1567 my ($signal, $cb) = @{$_[0]};
1323 1568
1324 $SIG{$signal} ||= sub { 1569 _sig_del;
1325 local $!; 1570
1326 syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV; 1571 delete $SIG_CB{$signal}{$cb};
1572
1573 $HAVE_ASYNC_INTERRUPT
1574 ? delete $SIG_ASY{$signal}
1575 : # delete doesn't work with older perls - they then
1576 # print weird messages, or just unconditionally exit
1577 # instead of getting the default action.
1327 undef $SIG_EV{$signal}; 1578 undef $SIG{$signal}
1579 unless keys %{ $SIG_CB{$signal} };
1328 }; 1580 };
1329
1330 # can't do signal processing without introducing races in pure perl,
1331 # so limit the signal latency.
1332 _sig_add;
1333 } 1581 };
1334 1582 die if $@;
1335 bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
1336}
1337
1338sub signal {
1339 # probe for availability of Async::Interrupt
1340 if (!$ENV{PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT} && eval "use Async::Interrupt 0.6 (); 1") {
1341 warn "AnyEvent: using Async::Interrupt for race-free signal handling.\n" if $VERBOSE >= 8;
1342
1343 $HAVE_ASYNC_INTERRUPT = 1;
1344 $SIGPIPE_R = new Async::Interrupt::EventPipe;
1345 $SIG_IO = AnyEvent->io (fh => $SIGPIPE_R->fileno, poll => "r", cb => \&_signal_exec);
1346
1347 } else {
1348 warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8;
1349
1350 require Fcntl;
1351
1352 if (AnyEvent::WIN32) {
1353 require AnyEvent::Util;
1354
1355 ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
1356 AnyEvent::Util::fh_nonblocking ($SIGPIPE_R) if $SIGPIPE_R;
1357 AnyEvent::Util::fh_nonblocking ($SIGPIPE_W) if $SIGPIPE_W; # just in case
1358 } else {
1359 pipe $SIGPIPE_R, $SIGPIPE_W;
1360 fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R;
1361 fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case
1362
1363 # not strictly required, as $^F is normally 2, but let's make sure...
1364 fcntl $SIGPIPE_R, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;
1365 fcntl $SIGPIPE_W, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;
1366 }
1367
1368 $SIGPIPE_R
1369 or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";
1370
1371 $SIG_IO = AnyEvent->io (fh => $SIGPIPE_R, poll => "r", cb => \&_signal_exec);
1372 }
1373
1374 *signal = \&_signal;
1375 &signal 1583 &signal
1376}
1377
1378sub AnyEvent::Base::signal::DESTROY {
1379 my ($signal, $cb) = @{$_[0]};
1380
1381 _sig_del;
1382
1383 delete $SIG_CB{$signal}{$cb};
1384
1385 $HAVE_ASYNC_INTERRUPT
1386 ? delete $SIG_ASY{$signal}
1387 : # delete doesn't work with older perls - they then
1388 # print weird messages, or just unconditionally exit
1389 # instead of getting the default action.
1390 undef $SIG{$signal}
1391 unless keys %{ $SIG_CB{$signal} };
1392} 1584}
1393 1585
1394# default implementation for ->child 1586# default implementation for ->child
1395 1587
1396our %PID_CB; 1588our %PID_CB;
1397our $CHLD_W; 1589our $CHLD_W;
1398our $CHLD_DELAY_W; 1590our $CHLD_DELAY_W;
1399our $WNOHANG; 1591our $WNOHANG;
1400 1592
1593sub _emit_childstatus($$) {
1594 my (undef, $rpid, $rstatus) = @_;
1595
1596 $_->($rpid, $rstatus)
1597 for values %{ $PID_CB{$rpid} || {} },
1598 values %{ $PID_CB{0} || {} };
1599}
1600
1401sub _sigchld { 1601sub _sigchld {
1602 my $pid;
1603
1604 AnyEvent->_emit_childstatus ($pid, $?)
1402 while (0 < (my $pid = waitpid -1, $WNOHANG)) { 1605 while ($pid = waitpid -1, $WNOHANG) > 0;
1403 $_->($pid, $?)
1404 for values %{ $PID_CB{$pid} || {} },
1405 values %{ $PID_CB{0} || {} };
1406 }
1407} 1606}
1408 1607
1409sub child { 1608sub child {
1410 my (undef, %arg) = @_; 1609 my (undef, %arg) = @_;
1411 1610
1418 $WNOHANG ||= $^O =~ /^(?:openbsd|netbsd|linux|freebsd|cygwin|MSWin32)$/ 1617 $WNOHANG ||= $^O =~ /^(?:openbsd|netbsd|linux|freebsd|cygwin|MSWin32)$/
1419 ? 1 1618 ? 1
1420 : eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1; 1619 : eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1;
1421 1620
1422 unless ($CHLD_W) { 1621 unless ($CHLD_W) {
1423 $CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld); 1622 $CHLD_W = AE::signal CHLD => \&_sigchld;
1424 # child could be a zombie already, so make at least one round 1623 # child could be a zombie already, so make at least one round
1425 &_sigchld; 1624 &_sigchld;
1426 } 1625 }
1427 1626
1428 bless [$pid, $arg{cb}], "AnyEvent::Base::child" 1627 bless [$pid, $arg{cb}], "AnyEvent::Base::child"
1454 # never use more then 50% of the time for the idle watcher, 1653 # never use more then 50% of the time for the idle watcher,
1455 # within some limits 1654 # within some limits
1456 $w = 0.0001 if $w < 0.0001; 1655 $w = 0.0001 if $w < 0.0001;
1457 $w = 5 if $w > 5; 1656 $w = 5 if $w > 5;
1458 1657
1459 $w = AnyEvent->timer (after => $w, cb => $rcb); 1658 $w = AE::timer $w, 0, $rcb;
1460 } else { 1659 } else {
1461 # clean up... 1660 # clean up...
1462 undef $w; 1661 undef $w;
1463 undef $rcb; 1662 undef $rcb;
1464 } 1663 }
1465 }; 1664 };
1466 1665
1467 $w = AnyEvent->timer (after => 0.05, cb => $rcb); 1666 $w = AE::timer 0.05, 0, $rcb;
1468 1667
1469 bless \\$cb, "AnyEvent::Base::idle" 1668 bless \\$cb, "AnyEvent::Base::idle"
1470} 1669}
1471 1670
1472sub AnyEvent::Base::idle::DESTROY { 1671sub AnyEvent::Base::idle::DESTROY {
1526 Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak}; 1725 Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak};
1527 wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0] 1726 wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0]
1528} 1727}
1529 1728
1530sub cb { 1729sub cb {
1531 $_[0]{_ae_cb} = $_[1] if @_ > 1; 1730 my $cv = shift;
1731
1732 @_
1733 and $cv->{_ae_cb} = shift
1734 and $cv->{_ae_sent}
1735 and (delete $cv->{_ae_cb})->($cv);
1736
1532 $_[0]{_ae_cb} 1737 $cv->{_ae_cb}
1533} 1738}
1534 1739
1535sub begin { 1740sub begin {
1536 ++$_[0]{_ae_counter}; 1741 ++$_[0]{_ae_counter};
1537 $_[0]{_ae_end_cb} = $_[1] if @_ > 1; 1742 $_[0]{_ae_end_cb} = $_[1] if @_ > 1;
1746 warn "read: $input\n"; # output what has been read 1951 warn "read: $input\n"; # output what has been read
1747 $cv->send if $input =~ /^q/i; # quit program if /^q/i 1952 $cv->send if $input =~ /^q/i; # quit program if /^q/i
1748 }, 1953 },
1749 ); 1954 );
1750 1955
1751 my $time_watcher; # can only be used once
1752
1753 sub new_timer {
1754 $timer = AnyEvent->timer (after => 1, cb => sub { 1956 my $time_watcher = AnyEvent->timer (after => 1, interval => 1, cb => sub {
1755 warn "timeout\n"; # print 'timeout' about every second 1957 warn "timeout\n"; # print 'timeout' at most every second
1756 &new_timer; # and restart the time
1757 }); 1958 });
1758 }
1759
1760 new_timer; # create first timer
1761 1959
1762 $cv->recv; # wait until user enters /^q/i 1960 $cv->recv; # wait until user enters /^q/i
1763 1961
1764=head1 REAL-WORLD EXAMPLE 1962=head1 REAL-WORLD EXAMPLE
1765 1963
1896through AnyEvent. The benchmark creates a lot of timers (with a zero 2094through AnyEvent. The benchmark creates a lot of timers (with a zero
1897timeout) and I/O watchers (watching STDOUT, a pty, to become writable, 2095timeout) and I/O watchers (watching STDOUT, a pty, to become writable,
1898which it is), lets them fire exactly once and destroys them again. 2096which it is), lets them fire exactly once and destroys them again.
1899 2097
1900Source code for this benchmark is found as F<eg/bench> in the AnyEvent 2098Source code for this benchmark is found as F<eg/bench> in the AnyEvent
1901distribution. 2099distribution. It uses the L<AE> interface, which makes a real difference
2100for the EV and Perl backends only.
1902 2101
1903=head3 Explanation of the columns 2102=head3 Explanation of the columns
1904 2103
1905I<watcher> is the number of event watchers created/destroyed. Since 2104I<watcher> is the number of event watchers created/destroyed. Since
1906different event models feature vastly different performances, each event 2105different event models feature vastly different performances, each event
1927watcher. 2126watcher.
1928 2127
1929=head3 Results 2128=head3 Results
1930 2129
1931 name watchers bytes create invoke destroy comment 2130 name watchers bytes create invoke destroy comment
1932 EV/EV 400000 224 0.47 0.35 0.27 EV native interface 2131 EV/EV 100000 223 0.47 0.43 0.27 EV native interface
1933 EV/Any 100000 224 2.88 0.34 0.27 EV + AnyEvent watchers 2132 EV/Any 100000 223 0.48 0.42 0.26 EV + AnyEvent watchers
1934 CoroEV/Any 100000 224 2.85 0.35 0.28 coroutines + Coro::Signal 2133 Coro::EV/Any 100000 223 0.47 0.42 0.26 coroutines + Coro::Signal
1935 Perl/Any 100000 452 4.13 0.73 0.95 pure perl implementation 2134 Perl/Any 100000 431 2.70 0.74 0.92 pure perl implementation
1936 Event/Event 16000 517 32.20 31.80 0.81 Event native interface 2135 Event/Event 16000 516 31.16 31.84 0.82 Event native interface
1937 Event/Any 16000 590 35.85 31.55 1.06 Event + AnyEvent watchers 2136 Event/Any 16000 1203 42.61 34.79 1.80 Event + AnyEvent watchers
1938 IOAsync/Any 16000 989 38.10 32.77 11.13 via IO::Async::Loop::IO_Poll 2137 IOAsync/Any 16000 1911 41.92 27.45 16.81 via IO::Async::Loop::IO_Poll
1939 IOAsync/Any 16000 990 37.59 29.50 10.61 via IO::Async::Loop::Epoll 2138 IOAsync/Any 16000 1726 40.69 26.37 15.25 via IO::Async::Loop::Epoll
1940 Glib/Any 16000 1357 102.33 12.31 51.00 quadratic behaviour 2139 Glib/Any 16000 1118 89.00 12.57 51.17 quadratic behaviour
1941 Tk/Any 2000 1860 27.20 66.31 14.00 SEGV with >> 2000 watchers 2140 Tk/Any 2000 1346 20.96 10.75 8.00 SEGV with >> 2000 watchers
1942 POE/Event 2000 6328 109.99 751.67 14.02 via POE::Loop::Event 2141 POE/Any 2000 6951 108.97 795.32 14.24 via POE::Loop::Event
1943 POE/Select 2000 6027 94.54 809.13 579.80 via POE::Loop::Select 2142 POE/Any 2000 6648 94.79 774.40 575.51 via POE::Loop::Select
1944 2143
1945=head3 Discussion 2144=head3 Discussion
1946 2145
1947The benchmark does I<not> measure scalability of the event loop very 2146The benchmark does I<not> measure scalability of the event loop very
1948well. For example, a select-based event loop (such as the pure perl one) 2147well. For example, a select-based event loop (such as the pure perl one)
1960benchmark machine, handling an event takes roughly 1600 CPU cycles with 2159benchmark machine, handling an event takes roughly 1600 CPU cycles with
1961EV, 3100 CPU cycles with AnyEvent's pure perl loop and almost 3000000 CPU 2160EV, 3100 CPU cycles with AnyEvent's pure perl loop and almost 3000000 CPU
1962cycles with POE. 2161cycles with POE.
1963 2162
1964C<EV> is the sole leader regarding speed and memory use, which are both 2163C<EV> is the sole leader regarding speed and memory use, which are both
1965maximal/minimal, respectively. Even when going through AnyEvent, it uses 2164maximal/minimal, respectively. When using the L<AE> API there is zero
2165overhead (when going through the AnyEvent API create is about 5-6 times
2166slower, with other times being equal, so still uses far less memory than
1966far less memory than any other event loop and is still faster than Event 2167any other event loop and is still faster than Event natively).
1967natively.
1968 2168
1969The pure perl implementation is hit in a few sweet spots (both the 2169The pure perl implementation is hit in a few sweet spots (both the
1970constant timeout and the use of a single fd hit optimisations in the perl 2170constant timeout and the use of a single fd hit optimisations in the perl
1971interpreter and the backend itself). Nevertheless this shows that it 2171interpreter and the backend itself). Nevertheless this shows that it
1972adds very little overhead in itself. Like any select-based backend its 2172adds very little overhead in itself. Like any select-based backend its
2046In this benchmark, we use 10000 socket pairs (20000 sockets), of which 100 2246In this benchmark, we use 10000 socket pairs (20000 sockets), of which 100
2047(1%) are active. This mirrors the activity of large servers with many 2247(1%) are active. This mirrors the activity of large servers with many
2048connections, most of which are idle at any one point in time. 2248connections, most of which are idle at any one point in time.
2049 2249
2050Source code for this benchmark is found as F<eg/bench2> in the AnyEvent 2250Source code for this benchmark is found as F<eg/bench2> in the AnyEvent
2051distribution. 2251distribution. It uses the L<AE> interface, which makes a real difference
2252for the EV and Perl backends only.
2052 2253
2053=head3 Explanation of the columns 2254=head3 Explanation of the columns
2054 2255
2055I<sockets> is the number of sockets, and twice the number of "servers" (as 2256I<sockets> is the number of sockets, and twice the number of "servers" (as
2056each server has a read and write socket end). 2257each server has a read and write socket end).
2064a new one that moves the timeout into the future. 2265a new one that moves the timeout into the future.
2065 2266
2066=head3 Results 2267=head3 Results
2067 2268
2068 name sockets create request 2269 name sockets create request
2069 EV 20000 69.01 11.16 2270 EV 20000 62.66 7.99
2070 Perl 20000 73.32 35.87 2271 Perl 20000 68.32 32.64
2071 IOAsync 20000 157.00 98.14 epoll 2272 IOAsync 20000 174.06 101.15 epoll
2072 IOAsync 20000 159.31 616.06 poll 2273 IOAsync 20000 174.67 610.84 poll
2073 Event 20000 212.62 257.32 2274 Event 20000 202.69 242.91
2074 Glib 20000 651.16 1896.30 2275 Glib 20000 557.01 1689.52
2075 POE 20000 349.67 12317.24 uses POE::Loop::Event 2276 POE 20000 341.54 12086.32 uses POE::Loop::Event
2076 2277
2077=head3 Discussion 2278=head3 Discussion
2078 2279
2079This benchmark I<does> measure scalability and overall performance of the 2280This benchmark I<does> measure scalability and overall performance of the
2080particular event loop. 2281particular event loop.
2206As you can see, the AnyEvent + EV combination even beats the 2407As you can see, the AnyEvent + EV combination even beats the
2207hand-optimised "raw sockets benchmark", while AnyEvent + its pure perl 2408hand-optimised "raw sockets benchmark", while AnyEvent + its pure perl
2208backend easily beats IO::Lambda and POE. 2409backend easily beats IO::Lambda and POE.
2209 2410
2210And even the 100% non-blocking version written using the high-level (and 2411And even the 100% non-blocking version written using the high-level (and
2211slow :) L<AnyEvent::Handle> abstraction beats both POE and IO::Lambda by a 2412slow :) L<AnyEvent::Handle> abstraction beats both POE and IO::Lambda
2212large margin, even though it does all of DNS, tcp-connect and socket I/O 2413higher level ("unoptimised") abstractions by a large margin, even though
2213in a non-blocking way. 2414it does all of DNS, tcp-connect and socket I/O in a non-blocking way.
2214 2415
2215The two AnyEvent benchmarks programs can be found as F<eg/ae0.pl> and 2416The two AnyEvent benchmarks programs can be found as F<eg/ae0.pl> and
2216F<eg/ae2.pl> in the AnyEvent distribution, the remaining benchmarks are 2417F<eg/ae2.pl> in the AnyEvent distribution, the remaining benchmarks are
2217part of the IO::lambda distribution and were used without any changes. 2418part of the IO::Lambda distribution and were used without any changes.
2218 2419
2219 2420
2220=head1 SIGNALS 2421=head1 SIGNALS
2221 2422
2222AnyEvent currently installs handlers for these signals: 2423AnyEvent currently installs handlers for these signals:
2264it's built-in modules) are required to use it. 2465it's built-in modules) are required to use it.
2265 2466
2266That does not mean that AnyEvent won't take advantage of some additional 2467That does not mean that AnyEvent won't take advantage of some additional
2267modules if they are installed. 2468modules if they are installed.
2268 2469
2269This section epxlains which additional modules will be used, and how they 2470This section explains which additional modules will be used, and how they
2270affect AnyEvent's operetion. 2471affect AnyEvent's operation.
2271 2472
2272=over 4 2473=over 4
2273 2474
2274=item L<Async::Interrupt> 2475=item L<Async::Interrupt>
2275 2476
2280catch the signals) with some delay (default is 10 seconds, look for 2481catch the signals) with some delay (default is 10 seconds, look for
2281C<$AnyEvent::MAX_SIGNAL_LATENCY>). 2482C<$AnyEvent::MAX_SIGNAL_LATENCY>).
2282 2483
2283If this module is available, then it will be used to implement signal 2484If this module is available, then it will be used to implement signal
2284catching, which means that signals will not be delayed, and the event loop 2485catching, which means that signals will not be delayed, and the event loop
2285will not be interrupted regularly, which is more efficient (And good for 2486will not be interrupted regularly, which is more efficient (and good for
2286battery life on laptops). 2487battery life on laptops).
2287 2488
2288This affects not just the pure-perl event loop, but also other event loops 2489This affects not just the pure-perl event loop, but also other event loops
2289that have no signal handling on their own (e.g. Glib, Tk, Qt). 2490that have no signal handling on their own (e.g. Glib, Tk, Qt).
2290 2491
2311lot less memory), but otherwise doesn't affect guard operation much. It is 2512lot less memory), but otherwise doesn't affect guard operation much. It is
2312purely used for performance. 2513purely used for performance.
2313 2514
2314=item L<JSON> and L<JSON::XS> 2515=item L<JSON> and L<JSON::XS>
2315 2516
2316This module is required when you want to read or write JSON data via 2517One of these modules is required when you want to read or write JSON data
2317L<AnyEvent::Handle>. It is also written in pure-perl, but can take 2518via L<AnyEvent::Handle>. It is also written in pure-perl, but can take
2318advantage of the ulta-high-speed L<JSON::XS> module when it is installed. 2519advantage of the ultra-high-speed L<JSON::XS> module when it is installed.
2319 2520
2320In fact, L<AnyEvent::Handle> will use L<JSON::XS> by default if it is 2521In fact, L<AnyEvent::Handle> will use L<JSON::XS> by default if it is
2321installed. 2522installed.
2322 2523
2323=item L<Net::SSLeay> 2524=item L<Net::SSLeay>
2337 2538
2338 2539
2339=head1 FORK 2540=head1 FORK
2340 2541
2341Most event libraries are not fork-safe. The ones who are usually are 2542Most event libraries are not fork-safe. The ones who are usually are
2342because they rely on inefficient but fork-safe C<select> or C<poll> 2543because they rely on inefficient but fork-safe C<select> or C<poll> calls
2343calls. Only L<EV> is fully fork-aware. 2544- higher performance APIs such as BSD's kqueue or the dreaded Linux epoll
2545are usually badly thought-out hacks that are incompatible with fork in
2546one way or another. Only L<EV> is fully fork-aware and ensures that you
2547continue event-processing in both parent and child (or both, if you know
2548what you are doing).
2549
2550This means that, in general, you cannot fork and do event processing in
2551the child if the event library was initialised before the fork (which
2552usually happens when the first AnyEvent watcher is created, or the library
2553is loaded).
2344 2554
2345If you have to fork, you must either do so I<before> creating your first 2555If you have to fork, you must either do so I<before> creating your first
2346watcher OR you must not use AnyEvent at all in the child OR you must do 2556watcher OR you must not use AnyEvent at all in the child OR you must do
2347something completely out of the scope of AnyEvent. 2557something completely out of the scope of AnyEvent.
2558
2559The problem of doing event processing in the parent I<and> the child
2560is much more complicated: even for backends that I<are> fork-aware or
2561fork-safe, their behaviour is not usually what you want: fork clones all
2562watchers, that means all timers, I/O watchers etc. are active in both
2563parent and child, which is almost never what you want. USing C<exec>
2564to start worker children from some kind of manage rprocess is usually
2565preferred, because it is much easier and cleaner, at the expense of having
2566to have another binary.
2348 2567
2349 2568
2350=head1 SECURITY CONSIDERATIONS 2569=head1 SECURITY CONSIDERATIONS
2351 2570
2352AnyEvent can be forced to load any event model via 2571AnyEvent can be forced to load any event model via
2390L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>. 2609L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>.
2391 2610
2392Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>, 2611Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>,
2393L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>, 2612L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>,
2394L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>, 2613L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>,
2395L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>. 2614L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>, L<Anyevent::Impl::Irssi>.
2396 2615
2397Non-blocking file handles, sockets, TCP clients and 2616Non-blocking file handles, sockets, TCP clients and
2398servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>. 2617servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>.
2399 2618
2400Asynchronous DNS: L<AnyEvent::DNS>. 2619Asynchronous DNS: L<AnyEvent::DNS>.

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