… | |
… | |
176 | =head2 I/O WATCHERS |
176 | =head2 I/O WATCHERS |
177 | |
177 | |
178 | You can create an I/O watcher by calling the C<< AnyEvent->io >> method |
178 | You can create an I/O watcher by calling the C<< AnyEvent->io >> method |
179 | with the following mandatory key-value pairs as arguments: |
179 | with the following mandatory key-value pairs as arguments: |
180 | |
180 | |
181 | C<fh> is the Perl I<file handle> (I<not> file descriptor) to watch |
181 | C<fh> is the Perl I<file handle> (or a naked file descriptor) to watch |
182 | for events (AnyEvent might or might not keep a reference to this file |
182 | for events (AnyEvent might or might not keep a reference to this file |
183 | handle). Note that only file handles pointing to things for which |
183 | handle). Note that only file handles pointing to things for which |
184 | non-blocking operation makes sense are allowed. This includes sockets, |
184 | non-blocking operation makes sense are allowed. This includes sockets, |
185 | most character devices, pipes, fifos and so on, but not for example files |
185 | most character devices, pipes, fifos and so on, but not for example files |
186 | or block devices. |
186 | or block devices. |
… | |
… | |
463 | |
463 | |
464 | If you are familiar with some event loops you will know that all of them |
464 | If you are familiar with some event loops you will know that all of them |
465 | require you to run some blocking "loop", "run" or similar function that |
465 | require you to run some blocking "loop", "run" or similar function that |
466 | will actively watch for new events and call your callbacks. |
466 | will actively watch for new events and call your callbacks. |
467 | |
467 | |
468 | AnyEvent is different, it expects somebody else to run the event loop and |
468 | AnyEvent is slightly different: it expects somebody else to run the event |
469 | will only block when necessary (usually when told by the user). |
469 | loop and will only block when necessary (usually when told by the user). |
470 | |
470 | |
471 | The instrument to do that is called a "condition variable", so called |
471 | The instrument to do that is called a "condition variable", so called |
472 | because they represent a condition that must become true. |
472 | because they represent a condition that must become true. |
473 | |
473 | |
|
|
474 | Now is probably a good time to look at the examples further below. |
|
|
475 | |
474 | Condition variables can be created by calling the C<< AnyEvent->condvar |
476 | Condition variables can be created by calling the C<< AnyEvent->condvar |
475 | >> method, usually without arguments. The only argument pair allowed is |
477 | >> method, usually without arguments. The only argument pair allowed is |
476 | |
|
|
477 | C<cb>, which specifies a callback to be called when the condition variable |
478 | C<cb>, which specifies a callback to be called when the condition variable |
478 | becomes true, with the condition variable as the first argument (but not |
479 | becomes true, with the condition variable as the first argument (but not |
479 | the results). |
480 | the results). |
480 | |
481 | |
481 | After creation, the condition variable is "false" until it becomes "true" |
482 | After creation, the condition variable is "false" until it becomes "true" |
… | |
… | |
530 | after => 1, |
531 | after => 1, |
531 | cb => sub { $result_ready->send }, |
532 | cb => sub { $result_ready->send }, |
532 | ); |
533 | ); |
533 | |
534 | |
534 | # this "blocks" (while handling events) till the callback |
535 | # this "blocks" (while handling events) till the callback |
535 | # calls send |
536 | # calls -<send |
536 | $result_ready->recv; |
537 | $result_ready->recv; |
537 | |
538 | |
538 | Example: wait for a timer, but take advantage of the fact that |
539 | Example: wait for a timer, but take advantage of the fact that condition |
539 | condition variables are also code references. |
540 | variables are also callable directly. |
540 | |
541 | |
541 | my $done = AnyEvent->condvar; |
542 | my $done = AnyEvent->condvar; |
542 | my $delay = AnyEvent->timer (after => 5, cb => $done); |
543 | my $delay = AnyEvent->timer (after => 5, cb => $done); |
543 | $done->recv; |
544 | $done->recv; |
544 | |
545 | |
… | |
… | |
550 | |
551 | |
551 | ... |
552 | ... |
552 | |
553 | |
553 | my @info = $couchdb->info->recv; |
554 | my @info = $couchdb->info->recv; |
554 | |
555 | |
555 | And this is how you would just ste a callback to be called whenever the |
556 | And this is how you would just set a callback to be called whenever the |
556 | results are available: |
557 | results are available: |
557 | |
558 | |
558 | $couchdb->info->cb (sub { |
559 | $couchdb->info->cb (sub { |
559 | my @info = $_[0]->recv; |
560 | my @info = $_[0]->recv; |
560 | }); |
561 | }); |
… | |
… | |
578 | immediately from within send. |
579 | immediately from within send. |
579 | |
580 | |
580 | Any arguments passed to the C<send> call will be returned by all |
581 | Any arguments passed to the C<send> call will be returned by all |
581 | future C<< ->recv >> calls. |
582 | future C<< ->recv >> calls. |
582 | |
583 | |
583 | Condition variables are overloaded so one can call them directly |
584 | Condition variables are overloaded so one can call them directly (as if |
584 | (as a code reference). Calling them directly is the same as calling |
585 | they were a code reference). Calling them directly is the same as calling |
585 | C<send>. Note, however, that many C-based event loops do not handle |
586 | C<send>. |
586 | overloading, so as tempting as it may be, passing a condition variable |
|
|
587 | instead of a callback does not work. Both the pure perl and EV loops |
|
|
588 | support overloading, however, as well as all functions that use perl to |
|
|
589 | invoke a callback (as in L<AnyEvent::Socket> and L<AnyEvent::DNS> for |
|
|
590 | example). |
|
|
591 | |
587 | |
592 | =item $cv->croak ($error) |
588 | =item $cv->croak ($error) |
593 | |
589 | |
594 | Similar to send, but causes all call's to C<< ->recv >> to invoke |
590 | Similar to send, but causes all call's to C<< ->recv >> to invoke |
595 | C<Carp::croak> with the given error message/object/scalar. |
591 | C<Carp::croak> with the given error message/object/scalar. |
596 | |
592 | |
597 | This can be used to signal any errors to the condition variable |
593 | This can be used to signal any errors to the condition variable |
598 | user/consumer. |
594 | user/consumer. Doing it this way instead of calling C<croak> directly |
|
|
595 | delays the error detetcion, but has the overwhelmign advantage that it |
|
|
596 | diagnoses the error at the place where the result is expected, and not |
|
|
597 | deep in some event clalback without connection to the actual code causing |
|
|
598 | the problem. |
599 | |
599 | |
600 | =item $cv->begin ([group callback]) |
600 | =item $cv->begin ([group callback]) |
601 | |
601 | |
602 | =item $cv->end |
602 | =item $cv->end |
603 | |
|
|
604 | These two methods are EXPERIMENTAL and MIGHT CHANGE. |
|
|
605 | |
603 | |
606 | These two methods can be used to combine many transactions/events into |
604 | These two methods can be used to combine many transactions/events into |
607 | one. For example, a function that pings many hosts in parallel might want |
605 | one. For example, a function that pings many hosts in parallel might want |
608 | to use a condition variable for the whole process. |
606 | to use a condition variable for the whole process. |
609 | |
607 | |
… | |
… | |
611 | C<< ->end >> will decrement it. If the counter reaches C<0> in C<< ->end |
609 | C<< ->end >> will decrement it. If the counter reaches C<0> in C<< ->end |
612 | >>, the (last) callback passed to C<begin> will be executed. That callback |
610 | >>, the (last) callback passed to C<begin> will be executed. That callback |
613 | is I<supposed> to call C<< ->send >>, but that is not required. If no |
611 | is I<supposed> to call C<< ->send >>, but that is not required. If no |
614 | callback was set, C<send> will be called without any arguments. |
612 | callback was set, C<send> will be called without any arguments. |
615 | |
613 | |
616 | Let's clarify this with the ping example: |
614 | You can think of C<< $cv->send >> giving you an OR condition (one call |
|
|
615 | sends), while C<< $cv->begin >> and C<< $cv->end >> giving you an AND |
|
|
616 | condition (all C<begin> calls must be C<end>'ed before the condvar sends). |
|
|
617 | |
|
|
618 | Let's start with a simple example: you have two I/O watchers (for example, |
|
|
619 | STDOUT and STDERR for a program), and you want to wait for both streams to |
|
|
620 | close before activating a condvar: |
|
|
621 | |
|
|
622 | my $cv = AnyEvent->condvar; |
|
|
623 | |
|
|
624 | $cv->begin; # first watcher |
|
|
625 | my $w1 = AnyEvent->io (fh => $fh1, cb => sub { |
|
|
626 | defined sysread $fh1, my $buf, 4096 |
|
|
627 | or $cv->end; |
|
|
628 | }); |
|
|
629 | |
|
|
630 | $cv->begin; # second watcher |
|
|
631 | my $w2 = AnyEvent->io (fh => $fh2, cb => sub { |
|
|
632 | defined sysread $fh2, my $buf, 4096 |
|
|
633 | or $cv->end; |
|
|
634 | }); |
|
|
635 | |
|
|
636 | $cv->recv; |
|
|
637 | |
|
|
638 | This works because for every event source (EOF on file handle), there is |
|
|
639 | one call to C<begin>, so the condvar waits for all calls to C<end> before |
|
|
640 | sending. |
|
|
641 | |
|
|
642 | The ping example mentioned above is slightly more complicated, as the |
|
|
643 | there are results to be passwd back, and the number of tasks that are |
|
|
644 | begung can potentially be zero: |
617 | |
645 | |
618 | my $cv = AnyEvent->condvar; |
646 | my $cv = AnyEvent->condvar; |
619 | |
647 | |
620 | my %result; |
648 | my %result; |
621 | $cv->begin (sub { $cv->send (\%result) }); |
649 | $cv->begin (sub { $cv->send (\%result) }); |
… | |
… | |
641 | loop, which serves two important purposes: first, it sets the callback |
669 | loop, which serves two important purposes: first, it sets the callback |
642 | to be called once the counter reaches C<0>, and second, it ensures that |
670 | to be called once the counter reaches C<0>, and second, it ensures that |
643 | C<send> is called even when C<no> hosts are being pinged (the loop |
671 | C<send> is called even when C<no> hosts are being pinged (the loop |
644 | doesn't execute once). |
672 | doesn't execute once). |
645 | |
673 | |
646 | This is the general pattern when you "fan out" into multiple subrequests: |
674 | This is the general pattern when you "fan out" into multiple (but |
647 | use an outer C<begin>/C<end> pair to set the callback and ensure C<end> |
675 | potentially none) subrequests: use an outer C<begin>/C<end> pair to set |
648 | is called at least once, and then, for each subrequest you start, call |
676 | the callback and ensure C<end> is called at least once, and then, for each |
649 | C<begin> and for each subrequest you finish, call C<end>. |
677 | subrequest you start, call C<begin> and for each subrequest you finish, |
|
|
678 | call C<end>. |
650 | |
679 | |
651 | =back |
680 | =back |
652 | |
681 | |
653 | =head3 METHODS FOR CONSUMERS |
682 | =head3 METHODS FOR CONSUMERS |
654 | |
683 | |
… | |
… | |
670 | function will call C<croak>. |
699 | function will call C<croak>. |
671 | |
700 | |
672 | In list context, all parameters passed to C<send> will be returned, |
701 | In list context, all parameters passed to C<send> will be returned, |
673 | in scalar context only the first one will be returned. |
702 | in scalar context only the first one will be returned. |
674 | |
703 | |
|
|
704 | Note that doing a blocking wait in a callback is not supported by any |
|
|
705 | event loop, that is, recursive invocation of a blocking C<< ->recv |
|
|
706 | >> is not allowed, and the C<recv> call will C<croak> if such a |
|
|
707 | condition is detected. This condition can be slightly loosened by using |
|
|
708 | L<Coro::AnyEvent>, which allows you to do a blocking C<< ->recv >> from |
|
|
709 | any thread that doesn't run the event loop itself. |
|
|
710 | |
675 | Not all event models support a blocking wait - some die in that case |
711 | Not all event models support a blocking wait - some die in that case |
676 | (programs might want to do that to stay interactive), so I<if you are |
712 | (programs might want to do that to stay interactive), so I<if you are |
677 | using this from a module, never require a blocking wait>, but let the |
713 | using this from a module, never require a blocking wait>. Instead, let the |
678 | caller decide whether the call will block or not (for example, by coupling |
714 | caller decide whether the call will block or not (for example, by coupling |
679 | condition variables with some kind of request results and supporting |
715 | condition variables with some kind of request results and supporting |
680 | callbacks so the caller knows that getting the result will not block, |
716 | callbacks so the caller knows that getting the result will not block, |
681 | while still supporting blocking waits if the caller so desires). |
717 | while still supporting blocking waits if the caller so desires). |
682 | |
718 | |
683 | Another reason I<never> to C<< ->recv >> in a module is that you cannot |
|
|
684 | sensibly have two C<< ->recv >>'s in parallel, as that would require |
|
|
685 | multiple interpreters or coroutines/threads, none of which C<AnyEvent> |
|
|
686 | can supply. |
|
|
687 | |
|
|
688 | The L<Coro> module, however, I<can> and I<does> supply coroutines and, in |
|
|
689 | fact, L<Coro::AnyEvent> replaces AnyEvent's condvars by coroutine-safe |
|
|
690 | versions and also integrates coroutines into AnyEvent, making blocking |
|
|
691 | C<< ->recv >> calls perfectly safe as long as they are done from another |
|
|
692 | coroutine (one that doesn't run the event loop). |
|
|
693 | |
|
|
694 | You can ensure that C<< -recv >> never blocks by setting a callback and |
719 | You can ensure that C<< -recv >> never blocks by setting a callback and |
695 | only calling C<< ->recv >> from within that callback (or at a later |
720 | only calling C<< ->recv >> from within that callback (or at a later |
696 | time). This will work even when the event loop does not support blocking |
721 | time). This will work even when the event loop does not support blocking |
697 | waits otherwise. |
722 | waits otherwise. |
698 | |
723 | |
… | |
… | |
711 | variable itself. Calling C<recv> inside the callback or at any later time |
736 | variable itself. Calling C<recv> inside the callback or at any later time |
712 | is guaranteed not to block. |
737 | is guaranteed not to block. |
713 | |
738 | |
714 | =back |
739 | =back |
715 | |
740 | |
|
|
741 | =head1 SUPPORTED EVENT LOOPS/BACKENDS |
|
|
742 | |
|
|
743 | The available backend classes are (every class has its own manpage): |
|
|
744 | |
|
|
745 | =over 4 |
|
|
746 | |
|
|
747 | =item Backends that are autoprobed when no other event loop can be found. |
|
|
748 | |
|
|
749 | EV is the preferred backend when no other event loop seems to be in |
|
|
750 | use. If EV is not installed, then AnyEvent will try Event, and, failing |
|
|
751 | that, will fall back to its own pure-perl implementation, which is |
|
|
752 | available everywhere as it comes with AnyEvent itself. |
|
|
753 | |
|
|
754 | AnyEvent::Impl::EV based on EV (interface to libev, best choice). |
|
|
755 | AnyEvent::Impl::Event based on Event, very stable, few glitches. |
|
|
756 | AnyEvent::Impl::Perl pure-perl implementation, fast and portable. |
|
|
757 | |
|
|
758 | =item Backends that are transparently being picked up when they are used. |
|
|
759 | |
|
|
760 | These will be used when they are currently loaded when the first watcher |
|
|
761 | is created, in which case it is assumed that the application is using |
|
|
762 | them. This means that AnyEvent will automatically pick the right backend |
|
|
763 | when the main program loads an event module before anything starts to |
|
|
764 | create watchers. Nothing special needs to be done by the main program. |
|
|
765 | |
|
|
766 | AnyEvent::Impl::Glib based on Glib, slow but very stable. |
|
|
767 | AnyEvent::Impl::Tk based on Tk, very broken. |
|
|
768 | AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse. |
|
|
769 | AnyEvent::Impl::POE based on POE, very slow, some limitations. |
|
|
770 | |
|
|
771 | =item Backends with special needs. |
|
|
772 | |
|
|
773 | Qt requires the Qt::Application to be instantiated first, but will |
|
|
774 | otherwise be picked up automatically. As long as the main program |
|
|
775 | instantiates the application before any AnyEvent watchers are created, |
|
|
776 | everything should just work. |
|
|
777 | |
|
|
778 | AnyEvent::Impl::Qt based on Qt. |
|
|
779 | |
|
|
780 | Support for IO::Async can only be partial, as it is too broken and |
|
|
781 | architecturally limited to even support the AnyEvent API. It also |
|
|
782 | is the only event loop that needs the loop to be set explicitly, so |
|
|
783 | it can only be used by a main program knowing about AnyEvent. See |
|
|
784 | L<AnyEvent::Impl::Async> for the gory details. |
|
|
785 | |
|
|
786 | AnyEvent::Impl::IOAsync based on IO::Async, cannot be autoprobed. |
|
|
787 | |
|
|
788 | =item Event loops that are indirectly supported via other backends. |
|
|
789 | |
|
|
790 | Some event loops can be supported via other modules: |
|
|
791 | |
|
|
792 | There is no direct support for WxWidgets (L<Wx>) or L<Prima>. |
|
|
793 | |
|
|
794 | B<WxWidgets> has no support for watching file handles. However, you can |
|
|
795 | use WxWidgets through the POE adaptor, as POE has a Wx backend that simply |
|
|
796 | polls 20 times per second, which was considered to be too horrible to even |
|
|
797 | consider for AnyEvent. |
|
|
798 | |
|
|
799 | B<Prima> is not supported as nobody seems to be using it, but it has a POE |
|
|
800 | backend, so it can be supported through POE. |
|
|
801 | |
|
|
802 | AnyEvent knows about both L<Prima> and L<Wx>, however, and will try to |
|
|
803 | load L<POE> when detecting them, in the hope that POE will pick them up, |
|
|
804 | in which case everything will be automatic. |
|
|
805 | |
|
|
806 | =back |
|
|
807 | |
716 | =head1 GLOBAL VARIABLES AND FUNCTIONS |
808 | =head1 GLOBAL VARIABLES AND FUNCTIONS |
717 | |
809 | |
|
|
810 | These are not normally required to use AnyEvent, but can be useful to |
|
|
811 | write AnyEvent extension modules. |
|
|
812 | |
718 | =over 4 |
813 | =over 4 |
719 | |
814 | |
720 | =item $AnyEvent::MODEL |
815 | =item $AnyEvent::MODEL |
721 | |
816 | |
722 | Contains C<undef> until the first watcher is being created. Then it |
817 | Contains C<undef> until the first watcher is being created, before the |
|
|
818 | backend has been autodetected. |
|
|
819 | |
723 | contains the event model that is being used, which is the name of the |
820 | Afterwards it contains the event model that is being used, which is the |
724 | Perl class implementing the model. This class is usually one of the |
821 | name of the Perl class implementing the model. This class is usually one |
725 | C<AnyEvent::Impl:xxx> modules, but can be any other class in the case |
822 | of the C<AnyEvent::Impl:xxx> modules, but can be any other class in the |
726 | AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode>). |
823 | case AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode> it |
727 | |
824 | will be C<urxvt::anyevent>). |
728 | The known classes so far are: |
|
|
729 | |
|
|
730 | AnyEvent::Impl::EV based on EV (an interface to libev, best choice). |
|
|
731 | AnyEvent::Impl::Event based on Event, second best choice. |
|
|
732 | AnyEvent::Impl::Perl pure-perl implementation, fast and portable. |
|
|
733 | AnyEvent::Impl::Glib based on Glib, third-best choice. |
|
|
734 | AnyEvent::Impl::Tk based on Tk, very bad choice. |
|
|
735 | AnyEvent::Impl::Qt based on Qt, cannot be autoprobed (see its docs). |
|
|
736 | AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse. |
|
|
737 | AnyEvent::Impl::POE based on POE, not generic enough for full support. |
|
|
738 | |
|
|
739 | # warning, support for IO::Async is only partial, as it is too broken |
|
|
740 | # and limited toe ven support the AnyEvent API. See AnyEvent::Impl::Async. |
|
|
741 | AnyEvent::Impl::IOAsync based on IO::Async, cannot be autoprobed (see its docs). |
|
|
742 | |
|
|
743 | There is no support for WxWidgets, as WxWidgets has no support for |
|
|
744 | watching file handles. However, you can use WxWidgets through the |
|
|
745 | POE Adaptor, as POE has a Wx backend that simply polls 20 times per |
|
|
746 | second, which was considered to be too horrible to even consider for |
|
|
747 | AnyEvent. Likewise, other POE backends can be used by AnyEvent by using |
|
|
748 | it's adaptor. |
|
|
749 | |
|
|
750 | AnyEvent knows about L<Prima> and L<Wx> and will try to use L<POE> when |
|
|
751 | autodetecting them. |
|
|
752 | |
825 | |
753 | =item AnyEvent::detect |
826 | =item AnyEvent::detect |
754 | |
827 | |
755 | Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model |
828 | Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model |
756 | if necessary. You should only call this function right before you would |
829 | if necessary. You should only call this function right before you would |
757 | have created an AnyEvent watcher anyway, that is, as late as possible at |
830 | have created an AnyEvent watcher anyway, that is, as late as possible at |
758 | runtime. |
831 | runtime, and not e.g. while initialising of your module. |
|
|
832 | |
|
|
833 | If you need to do some initialisation before AnyEvent watchers are |
|
|
834 | created, use C<post_detect>. |
759 | |
835 | |
760 | =item $guard = AnyEvent::post_detect { BLOCK } |
836 | =item $guard = AnyEvent::post_detect { BLOCK } |
761 | |
837 | |
762 | Arranges for the code block to be executed as soon as the event model is |
838 | Arranges for the code block to be executed as soon as the event model is |
763 | autodetected (or immediately if this has already happened). |
839 | autodetected (or immediately if this has already happened). |
|
|
840 | |
|
|
841 | The block will be executed I<after> the actual backend has been detected |
|
|
842 | (C<$AnyEvent::MODEL> is set), but I<before> any watchers have been |
|
|
843 | created, so it is possible to e.g. patch C<@AnyEvent::ISA> or do |
|
|
844 | other initialisations - see the sources of L<AnyEvent::Strict> or |
|
|
845 | L<AnyEvent::AIO> to see how this is used. |
|
|
846 | |
|
|
847 | The most common usage is to create some global watchers, without forcing |
|
|
848 | event module detection too early, for example, L<AnyEvent::AIO> creates |
|
|
849 | and installs the global L<IO::AIO> watcher in a C<post_detect> block to |
|
|
850 | avoid autodetecting the event module at load time. |
764 | |
851 | |
765 | If called in scalar or list context, then it creates and returns an object |
852 | If called in scalar or list context, then it creates and returns an object |
766 | that automatically removes the callback again when it is destroyed. See |
853 | that automatically removes the callback again when it is destroyed. See |
767 | L<Coro::BDB> for a case where this is useful. |
854 | L<Coro::BDB> for a case where this is useful. |
768 | |
855 | |
… | |
… | |
771 | If there are any code references in this array (you can C<push> to it |
858 | If there are any code references in this array (you can C<push> to it |
772 | before or after loading AnyEvent), then they will called directly after |
859 | before or after loading AnyEvent), then they will called directly after |
773 | the event loop has been chosen. |
860 | the event loop has been chosen. |
774 | |
861 | |
775 | You should check C<$AnyEvent::MODEL> before adding to this array, though: |
862 | You should check C<$AnyEvent::MODEL> before adding to this array, though: |
776 | if it contains a true value then the event loop has already been detected, |
863 | if it is defined then the event loop has already been detected, and the |
777 | and the array will be ignored. |
864 | array will be ignored. |
778 | |
865 | |
779 | Best use C<AnyEvent::post_detect { BLOCK }> instead. |
866 | Best use C<AnyEvent::post_detect { BLOCK }> when your application allows |
|
|
867 | it,as it takes care of these details. |
|
|
868 | |
|
|
869 | This variable is mainly useful for modules that can do something useful |
|
|
870 | when AnyEvent is used and thus want to know when it is initialised, but do |
|
|
871 | not need to even load it by default. This array provides the means to hook |
|
|
872 | into AnyEvent passively, without loading it. |
780 | |
873 | |
781 | =back |
874 | =back |
782 | |
875 | |
783 | =head1 WHAT TO DO IN A MODULE |
876 | =head1 WHAT TO DO IN A MODULE |
784 | |
877 | |
… | |
… | |
839 | |
932 | |
840 | |
933 | |
841 | =head1 OTHER MODULES |
934 | =head1 OTHER MODULES |
842 | |
935 | |
843 | The following is a non-exhaustive list of additional modules that use |
936 | The following is a non-exhaustive list of additional modules that use |
844 | AnyEvent and can therefore be mixed easily with other AnyEvent modules |
937 | AnyEvent as a client and can therefore be mixed easily with other AnyEvent |
845 | in the same program. Some of the modules come with AnyEvent, some are |
938 | modules and other event loops in the same program. Some of the modules |
846 | available via CPAN. |
939 | come with AnyEvent, most are available via CPAN. |
847 | |
940 | |
848 | =over 4 |
941 | =over 4 |
849 | |
942 | |
850 | =item L<AnyEvent::Util> |
943 | =item L<AnyEvent::Util> |
851 | |
944 | |
… | |
… | |
860 | |
953 | |
861 | =item L<AnyEvent::Handle> |
954 | =item L<AnyEvent::Handle> |
862 | |
955 | |
863 | Provide read and write buffers, manages watchers for reads and writes, |
956 | Provide read and write buffers, manages watchers for reads and writes, |
864 | supports raw and formatted I/O, I/O queued and fully transparent and |
957 | supports raw and formatted I/O, I/O queued and fully transparent and |
865 | non-blocking SSL/TLS. |
958 | non-blocking SSL/TLS (via L<AnyEvent::TLS>. |
866 | |
959 | |
867 | =item L<AnyEvent::DNS> |
960 | =item L<AnyEvent::DNS> |
868 | |
961 | |
869 | Provides rich asynchronous DNS resolver capabilities. |
962 | Provides rich asynchronous DNS resolver capabilities. |
870 | |
963 | |
… | |
… | |
898 | |
991 | |
899 | =item L<AnyEvent::GPSD> |
992 | =item L<AnyEvent::GPSD> |
900 | |
993 | |
901 | A non-blocking interface to gpsd, a daemon delivering GPS information. |
994 | A non-blocking interface to gpsd, a daemon delivering GPS information. |
902 | |
995 | |
|
|
996 | =item L<AnyEvent::IRC> |
|
|
997 | |
|
|
998 | AnyEvent based IRC client module family (replacing the older Net::IRC3). |
|
|
999 | |
|
|
1000 | =item L<AnyEvent::XMPP> |
|
|
1001 | |
|
|
1002 | AnyEvent based XMPP (Jabber protocol) module family (replacing the older |
|
|
1003 | Net::XMPP2>. |
|
|
1004 | |
903 | =item L<AnyEvent::IGS> |
1005 | =item L<AnyEvent::IGS> |
904 | |
1006 | |
905 | A non-blocking interface to the Internet Go Server protocol (used by |
1007 | A non-blocking interface to the Internet Go Server protocol (used by |
906 | L<App::IGS>). |
1008 | L<App::IGS>). |
907 | |
1009 | |
908 | =item L<AnyEvent::IRC> |
|
|
909 | |
|
|
910 | AnyEvent based IRC client module family (replacing the older Net::IRC3). |
|
|
911 | |
|
|
912 | =item L<Net::XMPP2> |
|
|
913 | |
|
|
914 | AnyEvent based XMPP (Jabber protocol) module family. |
|
|
915 | |
|
|
916 | =item L<Net::FCP> |
1010 | =item L<Net::FCP> |
917 | |
1011 | |
918 | AnyEvent-based implementation of the Freenet Client Protocol, birthplace |
1012 | AnyEvent-based implementation of the Freenet Client Protocol, birthplace |
919 | of AnyEvent. |
1013 | of AnyEvent. |
920 | |
1014 | |
… | |
… | |
924 | |
1018 | |
925 | =item L<Coro> |
1019 | =item L<Coro> |
926 | |
1020 | |
927 | Has special support for AnyEvent via L<Coro::AnyEvent>. |
1021 | Has special support for AnyEvent via L<Coro::AnyEvent>. |
928 | |
1022 | |
929 | =item L<IO::Lambda> |
|
|
930 | |
|
|
931 | The lambda approach to I/O - don't ask, look there. Can use AnyEvent. |
|
|
932 | |
|
|
933 | =back |
1023 | =back |
934 | |
1024 | |
935 | =cut |
1025 | =cut |
936 | |
1026 | |
937 | package AnyEvent; |
1027 | package AnyEvent; |
938 | |
1028 | |
939 | no warnings; |
1029 | no warnings; |
940 | use strict qw(vars subs); |
1030 | use strict qw(vars subs); |
941 | |
1031 | |
942 | use Carp; |
1032 | use Carp (); |
943 | |
1033 | |
944 | our $VERSION = 4.412; |
1034 | our $VERSION = 4.82; |
945 | our $MODEL; |
1035 | our $MODEL; |
946 | |
1036 | |
947 | our $AUTOLOAD; |
1037 | our $AUTOLOAD; |
948 | our @ISA; |
1038 | our @ISA; |
949 | |
1039 | |
… | |
… | |
975 | [Event:: => AnyEvent::Impl::Event::], |
1065 | [Event:: => AnyEvent::Impl::Event::], |
976 | [AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl::], |
1066 | [AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl::], |
977 | # everything below here will not be autoprobed |
1067 | # everything below here will not be autoprobed |
978 | # as the pureperl backend should work everywhere |
1068 | # as the pureperl backend should work everywhere |
979 | # and is usually faster |
1069 | # and is usually faster |
980 | [Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles |
|
|
981 | [Glib:: => AnyEvent::Impl::Glib::], # becomes extremely slow with many watchers |
1070 | [Glib:: => AnyEvent::Impl::Glib::], # becomes extremely slow with many watchers |
982 | [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy |
1071 | [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy |
|
|
1072 | [Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles |
983 | [Qt:: => AnyEvent::Impl::Qt::], # requires special main program |
1073 | [Qt:: => AnyEvent::Impl::Qt::], # requires special main program |
984 | [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza |
1074 | [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza |
985 | [Wx:: => AnyEvent::Impl::POE::], |
1075 | [Wx:: => AnyEvent::Impl::POE::], |
986 | [Prima:: => AnyEvent::Impl::POE::], |
1076 | [Prima:: => AnyEvent::Impl::POE::], |
987 | # IO::Async is just too broken - we would need workaorunds for its |
1077 | # IO::Async is just too broken - we would need workarounds for its |
988 | # byzantine signal and broken child handling, among others. |
1078 | # byzantine signal and broken child handling, among others. |
989 | # IO::Async is rather hard to detect, as it doesn't have any |
1079 | # IO::Async is rather hard to detect, as it doesn't have any |
990 | # obvious default class. |
1080 | # obvious default class. |
991 | # [IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program |
1081 | # [IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program |
992 | # [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program |
1082 | # [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program |
… | |
… | |
1025 | |
1115 | |
1026 | if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) { |
1116 | if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) { |
1027 | my $model = "AnyEvent::Impl::$1"; |
1117 | my $model = "AnyEvent::Impl::$1"; |
1028 | if (eval "require $model") { |
1118 | if (eval "require $model") { |
1029 | $MODEL = $model; |
1119 | $MODEL = $model; |
1030 | warn "AnyEvent: loaded model '$model' (forced by \$PERL_ANYEVENT_MODEL), using it.\n" if $verbose > 1; |
1120 | warn "AnyEvent: loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.\n" if $verbose > 1; |
1031 | } else { |
1121 | } else { |
1032 | warn "AnyEvent: unable to load model '$model' (from \$PERL_ANYEVENT_MODEL):\n$@" if $verbose; |
1122 | warn "AnyEvent: unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@" if $verbose; |
1033 | } |
1123 | } |
1034 | } |
1124 | } |
1035 | |
1125 | |
1036 | # check for already loaded models |
1126 | # check for already loaded models |
1037 | unless ($MODEL) { |
1127 | unless ($MODEL) { |
… | |
… | |
1079 | |
1169 | |
1080 | sub AUTOLOAD { |
1170 | sub AUTOLOAD { |
1081 | (my $func = $AUTOLOAD) =~ s/.*://; |
1171 | (my $func = $AUTOLOAD) =~ s/.*://; |
1082 | |
1172 | |
1083 | $method{$func} |
1173 | $method{$func} |
1084 | or croak "$func: not a valid method for AnyEvent objects"; |
1174 | or Carp::croak "$func: not a valid method for AnyEvent objects"; |
1085 | |
1175 | |
1086 | detect unless $MODEL; |
1176 | detect unless $MODEL; |
1087 | |
1177 | |
1088 | my $class = shift; |
1178 | my $class = shift; |
1089 | $class->$func (@_); |
1179 | $class->$func (@_); |
… | |
… | |
1094 | # allow only one watcher per fd, so we dup it to get a different one). |
1184 | # allow only one watcher per fd, so we dup it to get a different one). |
1095 | sub _dupfh($$;$$) { |
1185 | sub _dupfh($$;$$) { |
1096 | my ($poll, $fh, $r, $w) = @_; |
1186 | my ($poll, $fh, $r, $w) = @_; |
1097 | |
1187 | |
1098 | # cygwin requires the fh mode to be matching, unix doesn't |
1188 | # cygwin requires the fh mode to be matching, unix doesn't |
1099 | my ($rw, $mode) = $poll eq "r" ? ($r, "<") |
1189 | my ($rw, $mode) = $poll eq "r" ? ($r, "<") : ($w, ">"); |
1100 | : $poll eq "w" ? ($w, ">") |
|
|
1101 | : Carp::croak "AnyEvent->io requires poll set to either 'r' or 'w'"; |
|
|
1102 | |
1190 | |
1103 | open my $fh2, "$mode&" . fileno $fh |
1191 | open my $fh2, "$mode&", $fh |
1104 | or die "cannot dup() filehandle: $!,"; |
1192 | or die "AnyEvent->io: cannot dup() filehandle in mode '$poll': $!,"; |
1105 | |
1193 | |
1106 | # we assume CLOEXEC is already set by perl in all important cases |
1194 | # we assume CLOEXEC is already set by perl in all important cases |
1107 | |
1195 | |
1108 | ($fh2, $rw) |
1196 | ($fh2, $rw) |
1109 | } |
1197 | } |
… | |
… | |
1284 | |
1372 | |
1285 | use overload |
1373 | use overload |
1286 | '&{}' => sub { my $self = shift; sub { $self->send (@_) } }, |
1374 | '&{}' => sub { my $self = shift; sub { $self->send (@_) } }, |
1287 | fallback => 1; |
1375 | fallback => 1; |
1288 | |
1376 | |
|
|
1377 | our $WAITING; |
|
|
1378 | |
1289 | sub _send { |
1379 | sub _send { |
1290 | # nop |
1380 | # nop |
1291 | } |
1381 | } |
1292 | |
1382 | |
1293 | sub send { |
1383 | sub send { |
… | |
… | |
1305 | sub ready { |
1395 | sub ready { |
1306 | $_[0]{_ae_sent} |
1396 | $_[0]{_ae_sent} |
1307 | } |
1397 | } |
1308 | |
1398 | |
1309 | sub _wait { |
1399 | sub _wait { |
|
|
1400 | $WAITING |
|
|
1401 | and !$_[0]{_ae_sent} |
|
|
1402 | and Carp::croak "AnyEvent::CondVar: recursive blocking wait detected"; |
|
|
1403 | |
|
|
1404 | local $WAITING = 1; |
1310 | AnyEvent->one_event while !$_[0]{_ae_sent}; |
1405 | AnyEvent->one_event while !$_[0]{_ae_sent}; |
1311 | } |
1406 | } |
1312 | |
1407 | |
1313 | sub recv { |
1408 | sub recv { |
1314 | $_[0]->_wait; |
1409 | $_[0]->_wait; |
… | |
… | |
1441 | |
1536 | |
1442 | =item C<PERL_ANYEVENT_MAX_FORKS> |
1537 | =item C<PERL_ANYEVENT_MAX_FORKS> |
1443 | |
1538 | |
1444 | The maximum number of child processes that C<AnyEvent::Util::fork_call> |
1539 | The maximum number of child processes that C<AnyEvent::Util::fork_call> |
1445 | will create in parallel. |
1540 | will create in parallel. |
|
|
1541 | |
|
|
1542 | =item C<PERL_ANYEVENT_MAX_OUTSTANDING_DNS> |
|
|
1543 | |
|
|
1544 | The default value for the C<max_outstanding> parameter for the default DNS |
|
|
1545 | resolver - this is the maximum number of parallel DNS requests that are |
|
|
1546 | sent to the DNS server. |
|
|
1547 | |
|
|
1548 | =item C<PERL_ANYEVENT_RESOLV_CONF> |
|
|
1549 | |
|
|
1550 | The file to use instead of F</etc/resolv.conf> (or OS-specific |
|
|
1551 | configuration) in the default resolver. When set to the empty string, no |
|
|
1552 | default config will be used. |
|
|
1553 | |
|
|
1554 | =item C<PERL_ANYEVENT_CA_FILE>, C<PERL_ANYEVENT_CA_PATH>. |
|
|
1555 | |
|
|
1556 | When neither C<ca_file> nor C<ca_path> was specified during |
|
|
1557 | L<AnyEvent::TLS> context creation, and either of these environment |
|
|
1558 | variables exist, they will be used to specify CA certificate locations |
|
|
1559 | instead of a system-dependent default. |
1446 | |
1560 | |
1447 | =back |
1561 | =back |
1448 | |
1562 | |
1449 | =head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE |
1563 | =head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE |
1450 | |
1564 | |
… | |
… | |
1695 | EV/Any 100000 224 2.88 0.34 0.27 EV + AnyEvent watchers |
1809 | EV/Any 100000 224 2.88 0.34 0.27 EV + AnyEvent watchers |
1696 | CoroEV/Any 100000 224 2.85 0.35 0.28 coroutines + Coro::Signal |
1810 | CoroEV/Any 100000 224 2.85 0.35 0.28 coroutines + Coro::Signal |
1697 | Perl/Any 100000 452 4.13 0.73 0.95 pure perl implementation |
1811 | Perl/Any 100000 452 4.13 0.73 0.95 pure perl implementation |
1698 | Event/Event 16000 517 32.20 31.80 0.81 Event native interface |
1812 | Event/Event 16000 517 32.20 31.80 0.81 Event native interface |
1699 | Event/Any 16000 590 35.85 31.55 1.06 Event + AnyEvent watchers |
1813 | Event/Any 16000 590 35.85 31.55 1.06 Event + AnyEvent watchers |
|
|
1814 | IOAsync/Any 16000 989 38.10 32.77 11.13 via IO::Async::Loop::IO_Poll |
|
|
1815 | IOAsync/Any 16000 990 37.59 29.50 10.61 via IO::Async::Loop::Epoll |
1700 | Glib/Any 16000 1357 102.33 12.31 51.00 quadratic behaviour |
1816 | Glib/Any 16000 1357 102.33 12.31 51.00 quadratic behaviour |
1701 | Tk/Any 2000 1860 27.20 66.31 14.00 SEGV with >> 2000 watchers |
1817 | Tk/Any 2000 1860 27.20 66.31 14.00 SEGV with >> 2000 watchers |
1702 | POE/Event 2000 6328 109.99 751.67 14.02 via POE::Loop::Event |
1818 | POE/Event 2000 6328 109.99 751.67 14.02 via POE::Loop::Event |
1703 | POE/Select 2000 6027 94.54 809.13 579.80 via POE::Loop::Select |
1819 | POE/Select 2000 6027 94.54 809.13 579.80 via POE::Loop::Select |
1704 | |
1820 | |
… | |
… | |
1733 | performance becomes really bad with lots of file descriptors (and few of |
1849 | performance becomes really bad with lots of file descriptors (and few of |
1734 | them active), of course, but this was not subject of this benchmark. |
1850 | them active), of course, but this was not subject of this benchmark. |
1735 | |
1851 | |
1736 | The C<Event> module has a relatively high setup and callback invocation |
1852 | The C<Event> module has a relatively high setup and callback invocation |
1737 | cost, but overall scores in on the third place. |
1853 | cost, but overall scores in on the third place. |
|
|
1854 | |
|
|
1855 | C<IO::Async> performs admirably well, about on par with C<Event>, even |
|
|
1856 | when using its pure perl backend. |
1738 | |
1857 | |
1739 | C<Glib>'s memory usage is quite a bit higher, but it features a |
1858 | C<Glib>'s memory usage is quite a bit higher, but it features a |
1740 | faster callback invocation and overall ends up in the same class as |
1859 | faster callback invocation and overall ends up in the same class as |
1741 | C<Event>. However, Glib scales extremely badly, doubling the number of |
1860 | C<Event>. However, Glib scales extremely badly, doubling the number of |
1742 | watchers increases the processing time by more than a factor of four, |
1861 | watchers increases the processing time by more than a factor of four, |
… | |
… | |
1820 | it to another server. This includes deleting the old timeout and creating |
1939 | it to another server. This includes deleting the old timeout and creating |
1821 | a new one that moves the timeout into the future. |
1940 | a new one that moves the timeout into the future. |
1822 | |
1941 | |
1823 | =head3 Results |
1942 | =head3 Results |
1824 | |
1943 | |
1825 | name sockets create request |
1944 | name sockets create request |
1826 | EV 20000 69.01 11.16 |
1945 | EV 20000 69.01 11.16 |
1827 | Perl 20000 73.32 35.87 |
1946 | Perl 20000 73.32 35.87 |
|
|
1947 | IOAsync 20000 157.00 98.14 epoll |
|
|
1948 | IOAsync 20000 159.31 616.06 poll |
1828 | Event 20000 212.62 257.32 |
1949 | Event 20000 212.62 257.32 |
1829 | Glib 20000 651.16 1896.30 |
1950 | Glib 20000 651.16 1896.30 |
1830 | POE 20000 349.67 12317.24 uses POE::Loop::Event |
1951 | POE 20000 349.67 12317.24 uses POE::Loop::Event |
1831 | |
1952 | |
1832 | =head3 Discussion |
1953 | =head3 Discussion |
1833 | |
1954 | |
1834 | This benchmark I<does> measure scalability and overall performance of the |
1955 | This benchmark I<does> measure scalability and overall performance of the |
1835 | particular event loop. |
1956 | particular event loop. |
… | |
… | |
1837 | EV is again fastest. Since it is using epoll on my system, the setup time |
1958 | EV is again fastest. Since it is using epoll on my system, the setup time |
1838 | is relatively high, though. |
1959 | is relatively high, though. |
1839 | |
1960 | |
1840 | Perl surprisingly comes second. It is much faster than the C-based event |
1961 | Perl surprisingly comes second. It is much faster than the C-based event |
1841 | loops Event and Glib. |
1962 | loops Event and Glib. |
|
|
1963 | |
|
|
1964 | IO::Async performs very well when using its epoll backend, and still quite |
|
|
1965 | good compared to Glib when using its pure perl backend. |
1842 | |
1966 | |
1843 | Event suffers from high setup time as well (look at its code and you will |
1967 | Event suffers from high setup time as well (look at its code and you will |
1844 | understand why). Callback invocation also has a high overhead compared to |
1968 | understand why). Callback invocation also has a high overhead compared to |
1845 | the C<< $_->() for .. >>-style loop that the Perl event loop uses. Event |
1969 | the C<< $_->() for .. >>-style loop that the Perl event loop uses. Event |
1846 | uses select or poll in basically all documented configurations. |
1970 | uses select or poll in basically all documented configurations. |
… | |
… | |
1979 | |
2103 | |
1980 | A handler for C<SIGCHLD> is installed by AnyEvent's child watcher |
2104 | A handler for C<SIGCHLD> is installed by AnyEvent's child watcher |
1981 | emulation for event loops that do not support them natively. Also, some |
2105 | emulation for event loops that do not support them natively. Also, some |
1982 | event loops install a similar handler. |
2106 | event loops install a similar handler. |
1983 | |
2107 | |
1984 | If, when AnyEvent is loaded, SIGCHLD is set to IGNORE, then AnyEvent will |
2108 | Additionally, when AnyEvent is loaded and SIGCHLD is set to IGNORE, then |
1985 | reset it to default, to avoid losing child exit statuses. |
2109 | AnyEvent will reset it to default, to avoid losing child exit statuses. |
1986 | |
2110 | |
1987 | =item SIGPIPE |
2111 | =item SIGPIPE |
1988 | |
2112 | |
1989 | A no-op handler is installed for C<SIGPIPE> when C<$SIG{PIPE}> is C<undef> |
2113 | A no-op handler is installed for C<SIGPIPE> when C<$SIG{PIPE}> is C<undef> |
1990 | when AnyEvent gets loaded. |
2114 | when AnyEvent gets loaded. |
… | |
… | |
2063 | L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>. |
2187 | L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>. |
2064 | |
2188 | |
2065 | Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>, |
2189 | Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>, |
2066 | L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>, |
2190 | L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>, |
2067 | L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>, |
2191 | L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>, |
2068 | L<AnyEvent::Impl::POE>. |
2192 | L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>. |
2069 | |
2193 | |
2070 | Non-blocking file handles, sockets, TCP clients and |
2194 | Non-blocking file handles, sockets, TCP clients and |
2071 | servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>. |
2195 | servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>. |
2072 | |
2196 | |
2073 | Asynchronous DNS: L<AnyEvent::DNS>. |
2197 | Asynchronous DNS: L<AnyEvent::DNS>. |
2074 | |
2198 | |
2075 | Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>, |
2199 | Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, |
|
|
2200 | L<Coro::Event>, |
2076 | |
2201 | |
2077 | Nontrivial usage examples: L<Net::FCP>, L<Net::XMPP2>, L<AnyEvent::DNS>. |
2202 | Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::XMPP>, |
|
|
2203 | L<AnyEvent::HTTP>. |
2078 | |
2204 | |
2079 | |
2205 | |
2080 | =head1 AUTHOR |
2206 | =head1 AUTHOR |
2081 | |
2207 | |
2082 | Marc Lehmann <schmorp@schmorp.de> |
2208 | Marc Lehmann <schmorp@schmorp.de> |