[ViewVC] Diff of: cvs/AnyEvent/lib/AnyEvent.pm

Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.228 by root, Wed Jul 8 01:11:12 2009 UTC vs.
Revision 1.258 by root, Sun Jul 26 05:57:05 2009 UTC

…		…
1	=head1 NAME	1	=head1 NAME
2		2
3	AnyEvent - provide framework for multiple event loops	3	AnyEvent - the DBI of event loop programming
4		4
5	EV, Event, Glib, Tk, Perl, Event::Lib, Qt and POE are various supported	5	EV, Event, Glib, Tk, Perl, Event::Lib, Irssi, rxvt-unicode, IO::Async, Qt
6	event loops.	6	and 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
42	This manpage is mainly a reference manual. If you are interested	42	This manpage is mainly a reference manual. If you are interested
43	in a tutorial or some gentle introduction, have a look at the	43	in a tutorial or some gentle introduction, have a look at the
44	L<AnyEvent::Intro> manpage.	44	L<AnyEvent::Intro> manpage.
		45
		46	=head1 SUPPORT
		47
		48	There is a mailinglist for discussing all things AnyEvent, and an IRC
		49	channel, too.
		50
		51	See the AnyEvent project page at the B<Schmorpforge Ta-Sa Software
		52	Repository>, 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
48	Glib, POE, IO::Async, Event... CPAN offers event models by the dozen	56	Glib, POE, IO::Async, Event... CPAN offers event models by the dozen
49	nowadays. So what is different about AnyEvent?	57	nowadays. So what is different about AnyEvent?
…		…
176	=head2 I/O WATCHERS	184	=head2 I/O WATCHERS
177		185
178	You can create an I/O watcher by calling the C<< AnyEvent->io >> method	186	You can create an I/O watcher by calling the C<< AnyEvent->io >> method
179	with the following mandatory key-value pairs as arguments:	187	with the following mandatory key-value pairs as arguments:
180		188
181	C<fh> is the Perl I<file handle> (I<not> file descriptor, see below) to	189	C<fh> is the Perl I<file handle> (or a naked file descriptor) to watch
182	watch for events (AnyEvent might or might not keep a reference to this	190	for events (AnyEvent might or might not keep a reference to this file
183	file handle). Note that only file handles pointing to things for which	191	handle). Note that only file handles pointing to things for which
184	non-blocking operation makes sense are allowed. This includes sockets,	192	non-blocking operation makes sense are allowed. This includes sockets,
185	most character devices, pipes, fifos and so on, but not for example files	193	most character devices, pipes, fifos and so on, but not for example files
186	or block devices.	194	or block devices.
187		195
188	C<poll> must be a string that is either C<r> or C<w>, which creates a	196	C<poll> must be a string that is either C<r> or C<w>, which creates a
…		…
209	chomp (my $input = <STDIN>);	217	chomp (my $input = <STDIN>);
210	warn "read: $input\n";	218	warn "read: $input\n";
211	undef $w;	219	undef $w;
212	});	220	});
213		221
214	=head3 GETTING A FILE HANDLE FROM A FILE DESCRIPTOR
215
216	It is not uncommon to only have a file descriptor, while AnyEvent requires
217	a Perl file handle.
218
219	There are basically two methods to convert a file descriptor into a file handle. If you own
220	the file descriptor, you can open it with C<&=>, as in:
221
222	open my $fh, "<&=$fileno" or die "xxx: §!";
223
224	This will "own" the file descriptor, meaning that when C<$fh> is
225	destroyed, it will automatically close the C<$fileno>. Also, note that
226	the open mode (read, write, read/write) must correspond with how the
227	underlying file descriptor was opened.
228
229	In many cases, taking over the file descriptor is now what you want, in
230	which case the only alternative is to dup the file descriptor:
231
232	open my $fh, "<&$fileno" or die "xxx: $!";
233
234	This has the advantage of not closing the file descriptor and the
235	disadvantage of making a slow copy.
236
237	=head2 TIME WATCHERS	222	=head2 TIME WATCHERS
238		223
239	You can create a time watcher by calling the C<< AnyEvent->timer >>	224	You can create a time watcher by calling the C<< AnyEvent->timer >>
240	method with the following mandatory arguments:	225	method with the following mandatory arguments:
241		226
…		…
384	invocation, and callback invocation will be synchronous. Synchronous means	369	invocation, and callback invocation will be synchronous. Synchronous means
385	that it might take a while until the signal gets handled by the process,	370	that it might take a while until the signal gets handled by the process,
386	but it is guaranteed not to interrupt any other callbacks.	371	but it is guaranteed not to interrupt any other callbacks.
387		372
388	The main advantage of using these watchers is that you can share a signal	373	The main advantage of using these watchers is that you can share a signal
389	between multiple watchers.	374	between multiple watchers, and AnyEvent will ensure that signals will not
		375	interrupt your program at bad times.
390		376
391	This watcher might use C<%SIG>, so programs overwriting those signals	377	This watcher might use C<%SIG> (depending on the event loop used),
392	directly will likely not work correctly.	378	so programs overwriting those signals directly will likely not work
		379	correctly.
393		380
394	Example: exit on SIGINT	381	Example: exit on SIGINT
395		382
396	my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });	383	my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });
397		384
		385	=head3 Signal Races, Delays and Workarounds
		386
		387	Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching
		388	callbacks to signals in a generic way, which is a pity, as you cannot do
		389	race-free signal handling in perl. AnyEvent will try to do it's best, but
		390	in some cases, signals will be delayed. The maximum time a signal might
		391	be delayed is specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10
		392	seconds). This variable can be changed only before the first signal
		393	watcher is created, and should be left alone otherwise. Higher values
		394	will cause fewer spurious wake-ups, which is better for power and CPU
		395	saving. All these problems can be avoided by installing the optional
		396	L<Async::Interrupt> module. This will not work with inherently broken
		397	event loops such as L<Event> or L<Event::Lib> (and not with L<POE>
		398	currently, as POE does it's own workaround with one-second latency). With
		399	those, you just have to suffer the delays.
		400
398	=head2 CHILD PROCESS WATCHERS	401	=head2 CHILD PROCESS WATCHERS
399		402
400	You can also watch on a child process exit and catch its exit status.	403	You can also watch on a child process exit and catch its exit status.
401		404
402	The child process is specified by the C<pid> argument (if set to C<0>, it	405	The child process is specified by the C<pid> argument (one some backends,
403	watches for any child process exit). The watcher will triggered only when	406	using C<0> watches for any child process exit, on others this will
404	the child process has finished and an exit status is available, not on	407	croak). The watcher will be triggered only when the child process has
405	any trace events (stopped/continued).	408	finished and an exit status is available, not on any trace events
		409	(stopped/continued).
406		410
407	The callback will be called with the pid and exit status (as returned by	411	The callback will be called with the pid and exit status (as returned by
408	waitpid), so unlike other watcher types, you I<can> rely on child watcher	412	waitpid), so unlike other watcher types, you I<can> rely on child watcher
409	callback arguments.	413	callback arguments.
410		414
…		…
426		430
427	This means you cannot create a child watcher as the very first	431	This means you cannot create a child watcher as the very first
428	thing in an AnyEvent program, you I<have> to create at least one	432	thing in an AnyEvent program, you I<have> to create at least one
429	watcher before you C<fork> the child (alternatively, you can call	433	watcher before you C<fork> the child (alternatively, you can call
430	C<AnyEvent::detect>).	434	C<AnyEvent::detect>).
		435
		436	As most event loops do not support waiting for child events, they will be
		437	emulated by AnyEvent in most cases, in which the latency and race problems
		438	mentioned in the description of signal watchers apply.
431		439
432	Example: fork a process and wait for it	440	Example: fork a process and wait for it
433		441
434	my $done = AnyEvent->condvar;	442	my $done = AnyEvent->condvar;
435		443
…		…
486		494
487	If you are familiar with some event loops you will know that all of them	495	If you are familiar with some event loops you will know that all of them
488	require you to run some blocking "loop", "run" or similar function that	496	require you to run some blocking "loop", "run" or similar function that
489	will actively watch for new events and call your callbacks.	497	will actively watch for new events and call your callbacks.
490		498
491	AnyEvent is different, it expects somebody else to run the event loop and	499	AnyEvent is slightly different: it expects somebody else to run the event
492	will only block when necessary (usually when told by the user).	500	loop and will only block when necessary (usually when told by the user).
493		501
494	The instrument to do that is called a "condition variable", so called	502	The instrument to do that is called a "condition variable", so called
495	because they represent a condition that must become true.	503	because they represent a condition that must become true.
496		504
		505	Now is probably a good time to look at the examples further below.
		506
497	Condition variables can be created by calling the C<< AnyEvent->condvar	507	Condition variables can be created by calling the C<< AnyEvent->condvar
498	>> method, usually without arguments. The only argument pair allowed is	508	>> method, usually without arguments. The only argument pair allowed is
499
500	C<cb>, which specifies a callback to be called when the condition variable	509	C<cb>, which specifies a callback to be called when the condition variable
501	becomes true, with the condition variable as the first argument (but not	510	becomes true, with the condition variable as the first argument (but not
502	the results).	511	the results).
503		512
504	After creation, the condition variable is "false" until it becomes "true"	513	After creation, the condition variable is "false" until it becomes "true"
…		…
509	Condition variables are similar to callbacks, except that you can	518	Condition variables are similar to callbacks, except that you can
510	optionally wait for them. They can also be called merge points - points	519	optionally wait for them. They can also be called merge points - points
511	in time where multiple outstanding events have been processed. And yet	520	in time where multiple outstanding events have been processed. And yet
512	another way to call them is transactions - each condition variable can be	521	another way to call them is transactions - each condition variable can be
513	used to represent a transaction, which finishes at some point and delivers	522	used to represent a transaction, which finishes at some point and delivers
514	a result.	523	a result. And yet some people know them as "futures" - a promise to
		524	compute/deliver something that you can wait for.
515		525
516	Condition variables are very useful to signal that something has finished,	526	Condition variables are very useful to signal that something has finished,
517	for example, if you write a module that does asynchronous http requests,	527	for example, if you write a module that does asynchronous http requests,
518	then a condition variable would be the ideal candidate to signal the	528	then a condition variable would be the ideal candidate to signal the
519	availability of results. The user can either act when the callback is	529	availability of results. The user can either act when the callback is
…		…
553	after => 1,	563	after => 1,
554	cb => sub { $result_ready->send },	564	cb => sub { $result_ready->send },
555	);	565	);
556		566
557	# this "blocks" (while handling events) till the callback	567	# this "blocks" (while handling events) till the callback
558	# calls send	568	# calls -<send
559	$result_ready->recv;	569	$result_ready->recv;
560		570
561	Example: wait for a timer, but take advantage of the fact that	571	Example: wait for a timer, but take advantage of the fact that condition
562	condition variables are also code references.	572	variables are also callable directly.
563		573
564	my $done = AnyEvent->condvar;	574	my $done = AnyEvent->condvar;
565	my $delay = AnyEvent->timer (after => 5, cb => $done);	575	my $delay = AnyEvent->timer (after => 5, cb => $done);
566	$done->recv;	576	$done->recv;
567		577
…		…
573		583
574	...	584	...
575		585
576	my @info = $couchdb->info->recv;	586	my @info = $couchdb->info->recv;
577		587
578	And this is how you would just ste a callback to be called whenever the	588	And this is how you would just set a callback to be called whenever the
579	results are available:	589	results are available:
580		590
581	$couchdb->info->cb (sub {	591	$couchdb->info->cb (sub {
582	my @info = $_[0]->recv;	592	my @info = $_[0]->recv;
583	});	593	});
…		…
601	immediately from within send.	611	immediately from within send.
602		612
603	Any arguments passed to the C<send> call will be returned by all	613	Any arguments passed to the C<send> call will be returned by all
604	future C<< ->recv >> calls.	614	future C<< ->recv >> calls.
605		615
606	Condition variables are overloaded so one can call them directly	616	Condition variables are overloaded so one can call them directly (as if
607	(as a code reference). Calling them directly is the same as calling	617	they were a code reference). Calling them directly is the same as calling
608	C<send>. Note, however, that many C-based event loops do not handle	618	C<send>.
609	overloading, so as tempting as it may be, passing a condition variable
610	instead of a callback does not work. Both the pure perl and EV loops
611	support overloading, however, as well as all functions that use perl to
612	invoke a callback (as in L<AnyEvent::Socket> and L<AnyEvent::DNS> for
613	example).
614		619
615	=item $cv->croak ($error)	620	=item $cv->croak ($error)
616		621
617	Similar to send, but causes all call's to C<< ->recv >> to invoke	622	Similar to send, but causes all call's to C<< ->recv >> to invoke
618	C<Carp::croak> with the given error message/object/scalar.	623	C<Carp::croak> with the given error message/object/scalar.
619		624
620	This can be used to signal any errors to the condition variable	625	This can be used to signal any errors to the condition variable
621	user/consumer.	626	user/consumer. Doing it this way instead of calling C<croak> directly
		627	delays the error detetcion, but has the overwhelmign advantage that it
		628	diagnoses the error at the place where the result is expected, and not
		629	deep in some event clalback without connection to the actual code causing
		630	the problem.
622		631
623	=item $cv->begin ([group callback])	632	=item $cv->begin ([group callback])
624		633
625	=item $cv->end	634	=item $cv->end
626		635
…		…
722	function will call C<croak>.	731	function will call C<croak>.
723		732
724	In list context, all parameters passed to C<send> will be returned,	733	In list context, all parameters passed to C<send> will be returned,
725	in scalar context only the first one will be returned.	734	in scalar context only the first one will be returned.
726		735
		736	Note that doing a blocking wait in a callback is not supported by any
		737	event loop, that is, recursive invocation of a blocking C<< ->recv
		738	>> is not allowed, and the C<recv> call will C<croak> if such a
		739	condition is detected. This condition can be slightly loosened by using
		740	L<Coro::AnyEvent>, which allows you to do a blocking C<< ->recv >> from
		741	any thread that doesn't run the event loop itself.
		742
727	Not all event models support a blocking wait - some die in that case	743	Not all event models support a blocking wait - some die in that case
728	(programs might want to do that to stay interactive), so I<if you are	744	(programs might want to do that to stay interactive), so I<if you are
729	using this from a module, never require a blocking wait>, but let the	745	using this from a module, never require a blocking wait>. Instead, let the
730	caller decide whether the call will block or not (for example, by coupling	746	caller decide whether the call will block or not (for example, by coupling
731	condition variables with some kind of request results and supporting	747	condition variables with some kind of request results and supporting
732	callbacks so the caller knows that getting the result will not block,	748	callbacks so the caller knows that getting the result will not block,
733	while still supporting blocking waits if the caller so desires).	749	while still supporting blocking waits if the caller so desires).
734		750
735	Another reason I<never> to C<< ->recv >> in a module is that you cannot
736	sensibly have two C<< ->recv >>'s in parallel, as that would require
737	multiple interpreters or coroutines/threads, none of which C<AnyEvent>
738	can supply.
739
740	The L<Coro> module, however, I<can> and I<does> supply coroutines and, in
741	fact, L<Coro::AnyEvent> replaces AnyEvent's condvars by coroutine-safe
742	versions and also integrates coroutines into AnyEvent, making blocking
743	C<< ->recv >> calls perfectly safe as long as they are done from another
744	coroutine (one that doesn't run the event loop).
745
746	You can ensure that C<< -recv >> never blocks by setting a callback and	751	You can ensure that C<< -recv >> never blocks by setting a callback and
747	only calling C<< ->recv >> from within that callback (or at a later	752	only calling C<< ->recv >> from within that callback (or at a later
748	time). This will work even when the event loop does not support blocking	753	time). This will work even when the event loop does not support blocking
749	waits otherwise.	754	waits otherwise.
750		755
…		…
763	variable itself. Calling C<recv> inside the callback or at any later time	768	variable itself. Calling C<recv> inside the callback or at any later time
764	is guaranteed not to block.	769	is guaranteed not to block.
765		770
766	=back	771	=back
767		772
		773	=head1 SUPPORTED EVENT LOOPS/BACKENDS
		774
		775	The available backend classes are (every class has its own manpage):
		776
		777	=over 4
		778
		779	=item Backends that are autoprobed when no other event loop can be found.
		780
		781	EV is the preferred backend when no other event loop seems to be in
		782	use. If EV is not installed, then AnyEvent will try Event, and, failing
		783	that, will fall back to its own pure-perl implementation, which is
		784	available everywhere as it comes with AnyEvent itself.
		785
		786	AnyEvent::Impl::EV based on EV (interface to libev, best choice).
		787	AnyEvent::Impl::Event based on Event, very stable, few glitches.
		788	AnyEvent::Impl::Perl pure-perl implementation, fast and portable.
		789
		790	=item Backends that are transparently being picked up when they are used.
		791
		792	These will be used when they are currently loaded when the first watcher
		793	is created, in which case it is assumed that the application is using
		794	them. This means that AnyEvent will automatically pick the right backend
		795	when the main program loads an event module before anything starts to
		796	create watchers. Nothing special needs to be done by the main program.
		797
		798	AnyEvent::Impl::Glib based on Glib, slow but very stable.
		799	AnyEvent::Impl::Tk based on Tk, very broken.
		800	AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.
		801	AnyEvent::Impl::POE based on POE, very slow, some limitations.
		802	AnyEvent::Impl::Irssi used when running within irssi.
		803
		804	=item Backends with special needs.
		805
		806	Qt requires the Qt::Application to be instantiated first, but will
		807	otherwise be picked up automatically. As long as the main program
		808	instantiates the application before any AnyEvent watchers are created,
		809	everything should just work.
		810
		811	AnyEvent::Impl::Qt based on Qt.
		812
		813	Support for IO::Async can only be partial, as it is too broken and
		814	architecturally limited to even support the AnyEvent API. It also
		815	is the only event loop that needs the loop to be set explicitly, so
		816	it can only be used by a main program knowing about AnyEvent. See
		817	L<AnyEvent::Impl::Async> for the gory details.
		818
		819	AnyEvent::Impl::IOAsync based on IO::Async, cannot be autoprobed.
		820
		821	=item Event loops that are indirectly supported via other backends.
		822
		823	Some event loops can be supported via other modules:
		824
		825	There is no direct support for WxWidgets (L<Wx>) or L<Prima>.
		826
		827	B<WxWidgets> has no support for watching file handles. However, you can
		828	use WxWidgets through the POE adaptor, as POE has a Wx backend that simply
		829	polls 20 times per second, which was considered to be too horrible to even
		830	consider for AnyEvent.
		831
		832	B<Prima> is not supported as nobody seems to be using it, but it has a POE
		833	backend, so it can be supported through POE.
		834
		835	AnyEvent knows about both L<Prima> and L<Wx>, however, and will try to
		836	load L<POE> when detecting them, in the hope that POE will pick them up,
		837	in which case everything will be automatic.
		838
		839	=back
		840
768	=head1 GLOBAL VARIABLES AND FUNCTIONS	841	=head1 GLOBAL VARIABLES AND FUNCTIONS
769		842
		843	These are not normally required to use AnyEvent, but can be useful to
		844	write AnyEvent extension modules.
		845
770	=over 4	846	=over 4
771		847
772	=item $AnyEvent::MODEL	848	=item $AnyEvent::MODEL
773		849
774	Contains C<undef> until the first watcher is being created. Then it	850	Contains C<undef> until the first watcher is being created, before the
		851	backend has been autodetected.
		852
775	contains the event model that is being used, which is the name of the	853	Afterwards it contains the event model that is being used, which is the
776	Perl class implementing the model. This class is usually one of the	854	name of the Perl class implementing the model. This class is usually one
777	C<AnyEvent::Impl:xxx> modules, but can be any other class in the case	855	of the C<AnyEvent::Impl:xxx> modules, but can be any other class in the
778	AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode>).	856	case AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode> it
779		857	will be C<urxvt::anyevent>).
780	The known classes so far are:
781
782	AnyEvent::Impl::EV based on EV (an interface to libev, best choice).
783	AnyEvent::Impl::Event based on Event, second best choice.
784	AnyEvent::Impl::Perl pure-perl implementation, fast and portable.
785	AnyEvent::Impl::Glib based on Glib, third-best choice.
786	AnyEvent::Impl::Tk based on Tk, very bad choice.
787	AnyEvent::Impl::Qt based on Qt, cannot be autoprobed (see its docs).
788	AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.
789	AnyEvent::Impl::POE based on POE, not generic enough for full support.
790
791	# warning, support for IO::Async is only partial, as it is too broken
792	# and limited toe ven support the AnyEvent API. See AnyEvent::Impl::Async.
793	AnyEvent::Impl::IOAsync based on IO::Async, cannot be autoprobed (see its docs).
794
795	There is no support for WxWidgets, as WxWidgets has no support for
796	watching file handles. However, you can use WxWidgets through the
797	POE Adaptor, as POE has a Wx backend that simply polls 20 times per
798	second, which was considered to be too horrible to even consider for
799	AnyEvent. Likewise, other POE backends can be used by AnyEvent by using
800	it's adaptor.
801
802	AnyEvent knows about L<Prima> and L<Wx> and will try to use L<POE> when
803	autodetecting them.
804		858
805	=item AnyEvent::detect	859	=item AnyEvent::detect
806		860
807	Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model	861	Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model
808	if necessary. You should only call this function right before you would	862	if necessary. You should only call this function right before you would
809	have created an AnyEvent watcher anyway, that is, as late as possible at	863	have created an AnyEvent watcher anyway, that is, as late as possible at
810	runtime.	864	runtime, and not e.g. while initialising of your module.
		865
		866	If you need to do some initialisation before AnyEvent watchers are
		867	created, use C<post_detect>.
811		868
812	=item $guard = AnyEvent::post_detect { BLOCK }	869	=item $guard = AnyEvent::post_detect { BLOCK }
813		870
814	Arranges for the code block to be executed as soon as the event model is	871	Arranges for the code block to be executed as soon as the event model is
815	autodetected (or immediately if this has already happened).	872	autodetected (or immediately if this has already happened).
816		873
		874	The block will be executed I<after> the actual backend has been detected
		875	(C<$AnyEvent::MODEL> is set), but I<before> any watchers have been
		876	created, so it is possible to e.g. patch C<@AnyEvent::ISA> or do
		877	other initialisations - see the sources of L<AnyEvent::Strict> or
		878	L<AnyEvent::AIO> to see how this is used.
		879
		880	The most common usage is to create some global watchers, without forcing
		881	event module detection too early, for example, L<AnyEvent::AIO> creates
		882	and installs the global L<IO::AIO> watcher in a C<post_detect> block to
		883	avoid autodetecting the event module at load time.
		884
817	If called in scalar or list context, then it creates and returns an object	885	If called in scalar or list context, then it creates and returns an object
818	that automatically removes the callback again when it is destroyed. See	886	that automatically removes the callback again when it is destroyed (or
		887	C<undef> when the hook was immediately executed). See L<AnyEvent::AIO> for
819	L<Coro::BDB> for a case where this is useful.	888	a case where this is useful.
		889
		890	Example: Create a watcher for the IO::AIO module and store it in
		891	C<$WATCHER>. Only do so after the event loop is initialised, though.
		892
		893	our WATCHER;
		894
		895	my $guard = AnyEvent::post_detect {
		896	$WATCHER = AnyEvent->io (fh => IO::AIO::poll_fileno, poll => 'r', cb => \&IO::AIO::poll_cb);
		897	};
		898
		899	# the \|\|= is important in case post_detect immediately runs the block,
		900	# as to not clobber the newly-created watcher. assigning both watcher and
		901	# post_detect guard to the same variable has the advantage of users being
		902	# able to just C<undef $WATCHER> if the watcher causes them grief.
		903
		904	$WATCHER \|\|= $guard;
820		905
821	=item @AnyEvent::post_detect	906	=item @AnyEvent::post_detect
822		907
823	If there are any code references in this array (you can C<push> to it	908	If there are any code references in this array (you can C<push> to it
824	before or after loading AnyEvent), then they will called directly after	909	before or after loading AnyEvent), then they will called directly after
825	the event loop has been chosen.	910	the event loop has been chosen.
826		911
827	You should check C<$AnyEvent::MODEL> before adding to this array, though:	912	You should check C<$AnyEvent::MODEL> before adding to this array, though:
828	if it contains a true value then the event loop has already been detected,	913	if it is defined then the event loop has already been detected, and the
829	and the array will be ignored.	914	array will be ignored.
830		915
831	Best use C<AnyEvent::post_detect { BLOCK }> instead.	916	Best use C<AnyEvent::post_detect { BLOCK }> when your application allows
		917	it,as it takes care of these details.
		918
		919	This variable is mainly useful for modules that can do something useful
		920	when AnyEvent is used and thus want to know when it is initialised, but do
		921	not need to even load it by default. This array provides the means to hook
		922	into AnyEvent passively, without loading it.
832		923
833	=back	924	=back
834		925
835	=head1 WHAT TO DO IN A MODULE	926	=head1 WHAT TO DO IN A MODULE
836		927
…		…
891		982
892		983
893	=head1 OTHER MODULES	984	=head1 OTHER MODULES
894		985
895	The following is a non-exhaustive list of additional modules that use	986	The following is a non-exhaustive list of additional modules that use
896	AnyEvent and can therefore be mixed easily with other AnyEvent modules	987	AnyEvent as a client and can therefore be mixed easily with other AnyEvent
897	in the same program. Some of the modules come with AnyEvent, some are	988	modules and other event loops in the same program. Some of the modules
898	available via CPAN.	989	come with AnyEvent, most are available via CPAN.
899		990
900	=over 4	991	=over 4
901		992
902	=item L<AnyEvent::Util>	993	=item L<AnyEvent::Util>
903		994
…		…
912		1003
913	=item L<AnyEvent::Handle>	1004	=item L<AnyEvent::Handle>
914		1005
915	Provide read and write buffers, manages watchers for reads and writes,	1006	Provide read and write buffers, manages watchers for reads and writes,
916	supports raw and formatted I/O, I/O queued and fully transparent and	1007	supports raw and formatted I/O, I/O queued and fully transparent and
917	non-blocking SSL/TLS.	1008	non-blocking SSL/TLS (via L<AnyEvent::TLS>.
918		1009
919	=item L<AnyEvent::DNS>	1010	=item L<AnyEvent::DNS>
920		1011
921	Provides rich asynchronous DNS resolver capabilities.	1012	Provides rich asynchronous DNS resolver capabilities.
922		1013
…		…
950		1041
951	=item L<AnyEvent::GPSD>	1042	=item L<AnyEvent::GPSD>
952		1043
953	A non-blocking interface to gpsd, a daemon delivering GPS information.	1044	A non-blocking interface to gpsd, a daemon delivering GPS information.
954		1045
		1046	=item L<AnyEvent::IRC>
		1047
		1048	AnyEvent based IRC client module family (replacing the older Net::IRC3).
		1049
		1050	=item L<AnyEvent::XMPP>
		1051
		1052	AnyEvent based XMPP (Jabber protocol) module family (replacing the older
		1053	Net::XMPP2>.
		1054
955	=item L<AnyEvent::IGS>	1055	=item L<AnyEvent::IGS>
956		1056
957	A non-blocking interface to the Internet Go Server protocol (used by	1057	A non-blocking interface to the Internet Go Server protocol (used by
958	L<App::IGS>).	1058	L<App::IGS>).
959		1059
960	=item L<AnyEvent::IRC>
961
962	AnyEvent based IRC client module family (replacing the older Net::IRC3).
963
964	=item L<Net::XMPP2>
965
966	AnyEvent based XMPP (Jabber protocol) module family.
967
968	=item L<Net::FCP>	1060	=item L<Net::FCP>
969		1061
970	AnyEvent-based implementation of the Freenet Client Protocol, birthplace	1062	AnyEvent-based implementation of the Freenet Client Protocol, birthplace
971	of AnyEvent.	1063	of AnyEvent.
972		1064
…		…
976		1068
977	=item L<Coro>	1069	=item L<Coro>
978		1070
979	Has special support for AnyEvent via L<Coro::AnyEvent>.	1071	Has special support for AnyEvent via L<Coro::AnyEvent>.
980		1072
981	=item L<IO::Lambda>
982
983	The lambda approach to I/O - don't ask, look there. Can use AnyEvent.
984
985	=back	1073	=back
986		1074
987	=cut	1075	=cut
988		1076
989	package AnyEvent;	1077	package AnyEvent;
990		1078
		1079	# basically a tuned-down version of common::sense
		1080	sub common_sense {
991	no warnings;	1081	# no warnings
		1082	${^WARNING_BITS} ^= ${^WARNING_BITS};
992	use strict qw(vars subs);	1083	# use strict vars subs
		1084	$^H \|= 0x00000600;
		1085	}
993		1086
		1087	BEGIN { AnyEvent::common_sense }
		1088
994	use Carp;	1089	use Carp ();
995		1090
996	our $VERSION = 4.8;	1091	our $VERSION = 4.87;
997	our $MODEL;	1092	our $MODEL;
998		1093
999	our $AUTOLOAD;	1094	our $AUTOLOAD;
1000	our @ISA;	1095	our @ISA;
1001		1096
1002	our @REGISTRY;	1097	our @REGISTRY;
1003		1098
1004	our $WIN32;	1099	our $WIN32;
		1100
		1101	our $VERBOSE;
1005		1102
1006	BEGIN {	1103	BEGIN {
1007	eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }";	1104	eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }";
1008	eval "sub TAINT(){ " . (${^TAINT}*1) . " }";	1105	eval "sub TAINT(){ " . (${^TAINT}*1) . " }";
1009		1106
1010	delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}	1107	delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}
1011	if ${^TAINT};	1108	if ${^TAINT};
1012	}
1013		1109
1014	our $verbose = $ENV{PERL_ANYEVENT_VERBOSE}*1;	1110	$VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1;
		1111
		1112	}
		1113
		1114	our $MAX_SIGNAL_LATENCY = 10;
1015		1115
1016	our %PROTOCOL; # (ipv4\|ipv6) => (1\|2), higher numbers are preferred	1116	our %PROTOCOL; # (ipv4\|ipv6) => (1\|2), higher numbers are preferred
1017		1117
1018	{	1118	{
1019	my $idx;	1119	my $idx;
…		…
1021	for reverse split /\s,\s/,	1121	for reverse split /\s,\s/,
1022	$ENV{PERL_ANYEVENT_PROTOCOLS} \|\| "ipv4,ipv6";	1122	$ENV{PERL_ANYEVENT_PROTOCOLS} \|\| "ipv4,ipv6";
1023	}	1123	}
1024		1124
1025	my @models = (	1125	my @models = (
1026	[EV:: => AnyEvent::Impl::EV::],	1126	[EV:: => AnyEvent::Impl::EV:: , 1],
1027	[Event:: => AnyEvent::Impl::Event::],	1127	[Event:: => AnyEvent::Impl::Event::, 1],
1028	[AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl::],	1128	[AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl:: , 1],
1029	# everything below here will not be autoprobed	1129	# everything below here will not (normally) be autoprobed
1030	# as the pureperl backend should work everywhere	1130	# as the pureperl backend should work everywhere
1031	# and is usually faster	1131	# and is usually faster
		1132	[Glib:: => AnyEvent::Impl::Glib:: , 1], # becomes extremely slow with many watchers
		1133	[Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy
		1134	[Irssi:: => AnyEvent::Impl::Irssi::], # Irssi has a bogus "Event" package
1032	[Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles	1135	[Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles
1033	[Glib:: => AnyEvent::Impl::Glib::], # becomes extremely slow with many watchers
1034	[Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy
1035	[Qt:: => AnyEvent::Impl::Qt::], # requires special main program	1136	[Qt:: => AnyEvent::Impl::Qt::], # requires special main program
1036	[POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza	1137	[POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza
1037	[Wx:: => AnyEvent::Impl::POE::],	1138	[Wx:: => AnyEvent::Impl::POE::],
1038	[Prima:: => AnyEvent::Impl::POE::],	1139	[Prima:: => AnyEvent::Impl::POE::],
1039	# IO::Async is just too broken - we would need workaorunds for its	1140	# IO::Async is just too broken - we would need workarounds for its
1040	# byzantine signal and broken child handling, among others.	1141	# byzantine signal and broken child handling, among others.
1041	# IO::Async is rather hard to detect, as it doesn't have any	1142	# IO::Async is rather hard to detect, as it doesn't have any
1042	# obvious default class.	1143	# obvious default class.
1043	# [IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program	1144	# [0, IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program
1044	# [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program	1145	# [0, IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program
1045	# [IO::Async::Notifier:: => AnyEvent::Impl::IOAsync::], # requires special main program	1146	# [0, IO::Async::Notifier:: => AnyEvent::Impl::IOAsync::], # requires special main program
1046	);	1147	);
1047		1148
1048	our %method = map +($_ => 1),	1149	our %method = map +($_ => 1),
1049	qw(io timer time now now_update signal child idle condvar one_event DESTROY);	1150	qw(io timer time now now_update signal child idle condvar one_event DESTROY);
1050		1151
…		…
1054	my ($cb) = @_;	1155	my ($cb) = @_;
1055		1156
1056	if ($MODEL) {	1157	if ($MODEL) {
1057	$cb->();	1158	$cb->();
1058		1159
1059	1	1160	undef
1060	} else {	1161	} else {
1061	push @post_detect, $cb;	1162	push @post_detect, $cb;
1062		1163
1063	defined wantarray	1164	defined wantarray
1064	? bless \$cb, "AnyEvent::Util::postdetect"	1165	? bless \$cb, "AnyEvent::Util::postdetect"
…		…
1070	@post_detect = grep $_ != ${$_[0]}, @post_detect;	1171	@post_detect = grep $_ != ${$_[0]}, @post_detect;
1071	}	1172	}
1072		1173
1073	sub detect() {	1174	sub detect() {
1074	unless ($MODEL) {	1175	unless ($MODEL) {
1075	no strict 'refs';
1076	local $SIG{__DIE__};	1176	local $SIG{__DIE__};
1077		1177
1078	if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) {	1178	if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) {
1079	my $model = "AnyEvent::Impl::$1";	1179	my $model = "AnyEvent::Impl::$1";
1080	if (eval "require $model") {	1180	if (eval "require $model") {
1081	$MODEL = $model;	1181	$MODEL = $model;
1082	warn "AnyEvent: loaded model '$model' (forced by \$PERL_ANYEVENT_MODEL), using it.\n" if $verbose > 1;	1182	warn "AnyEvent: loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.\n" if $VERBOSE >= 2;
1083	} else {	1183	} else {
1084	warn "AnyEvent: unable to load model '$model' (from \$PERL_ANYEVENT_MODEL):\n$@" if $verbose;	1184	warn "AnyEvent: unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@" if $VERBOSE;
1085	}	1185	}
1086	}	1186	}
1087		1187
1088	# check for already loaded models	1188	# check for already loaded models
1089	unless ($MODEL) {	1189	unless ($MODEL) {
1090	for (@REGISTRY, @models) {	1190	for (@REGISTRY, @models) {
1091	my ($package, $model) = @$_;	1191	my ($package, $model) = @$_;
1092	if (${"$package\::VERSION"} > 0) {	1192	if (${"$package\::VERSION"} > 0) {
1093	if (eval "require $model") {	1193	if (eval "require $model") {
1094	$MODEL = $model;	1194	$MODEL = $model;
1095	warn "AnyEvent: autodetected model '$model', using it.\n" if $verbose > 1;	1195	warn "AnyEvent: autodetected model '$model', using it.\n" if $VERBOSE >= 2;
1096	last;	1196	last;
1097	}	1197	}
1098	}	1198	}
1099	}	1199	}
1100		1200
1101	unless ($MODEL) {	1201	unless ($MODEL) {
1102	# try to load a model	1202	# try to autoload a model
1103
1104	for (@REGISTRY, @models) {	1203	for (@REGISTRY, @models) {
1105	my ($package, $model) = @$_;	1204	my ($package, $model, $autoload) = @$_;
		1205	if (
		1206	$autoload
1106	if (eval "require $package"	1207	and eval "require $package"
1107	and ${"$package\::VERSION"} > 0	1208	and ${"$package\::VERSION"} > 0
1108	and eval "require $model") {	1209	and eval "require $model"
		1210	) {
1109	$MODEL = $model;	1211	$MODEL = $model;
1110	warn "AnyEvent: autoprobed model '$model', using it.\n" if $verbose > 1;	1212	warn "AnyEvent: autoloaded model '$model', using it.\n" if $VERBOSE >= 2;
1111	last;	1213	last;
1112	}	1214	}
1113	}	1215	}
1114		1216
1115	$MODEL	1217	$MODEL
…		…
1131		1233
1132	sub AUTOLOAD {	1234	sub AUTOLOAD {
1133	(my $func = $AUTOLOAD) =~ s/.*://;	1235	(my $func = $AUTOLOAD) =~ s/.*://;
1134		1236
1135	$method{$func}	1237	$method{$func}
1136	or croak "$func: not a valid method for AnyEvent objects";	1238	or Carp::croak "$func: not a valid method for AnyEvent objects";
1137		1239
1138	detect unless $MODEL;	1240	detect unless $MODEL;
1139		1241
1140	my $class = shift;	1242	my $class = shift;
1141	$class->$func (@_);	1243	$class->$func (@_);
…		…
1146	# allow only one watcher per fd, so we dup it to get a different one).	1248	# allow only one watcher per fd, so we dup it to get a different one).
1147	sub _dupfh($$;$$) {	1249	sub _dupfh($$;$$) {
1148	my ($poll, $fh, $r, $w) = @_;	1250	my ($poll, $fh, $r, $w) = @_;
1149		1251
1150	# cygwin requires the fh mode to be matching, unix doesn't	1252	# cygwin requires the fh mode to be matching, unix doesn't
1151	my ($rw, $mode) = $poll eq "r" ? ($r, "<")	1253	my ($rw, $mode) = $poll eq "r" ? ($r, "<&") : ($w, ">&");
1152	: $poll eq "w" ? ($w, ">")
1153	: Carp::croak "AnyEvent->io requires poll set to either 'r' or 'w'";
1154		1254
1155	open my $fh2, "$mode&" . fileno $fh	1255	open my $fh2, $mode, $fh
1156	or die "cannot dup() filehandle: $!,";	1256	or die "AnyEvent->io: cannot dup() filehandle in mode '$poll': $!,";
1157		1257
1158	# we assume CLOEXEC is already set by perl in all important cases	1258	# we assume CLOEXEC is already set by perl in all important cases
1159		1259
1160	($fh2, $rw)	1260	($fh2, $rw)
1161	}	1261	}
1162		1262
1163	package AnyEvent::Base;	1263	package AnyEvent::Base;
1164		1264
1165	# default implementations for many methods	1265	# default implementations for many methods
1166		1266
1167	BEGIN {	1267	sub _time {
		1268	# probe for availability of Time::HiRes
1168	if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {	1269	if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {
		1270	warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8;
1169	*_time = \&Time::HiRes::time;	1271	*_time = \&Time::HiRes::time;
1170	# if (eval "use POSIX (); (POSIX::times())...	1272	# if (eval "use POSIX (); (POSIX::times())...
1171	} else {	1273	} else {
		1274	warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE;
1172	*_time = sub { time }; # epic fail	1275	*_time = sub { time }; # epic fail
1173	}	1276	}
		1277
		1278	&_time
1174	}	1279	}
1175		1280
1176	sub time { _time }	1281	sub time { _time }
1177	sub now { _time }	1282	sub now { _time }
1178	sub now_update { }	1283	sub now_update { }
…		…
1183	bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"	1288	bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"
1184	}	1289	}
1185		1290
1186	# default implementation for ->signal	1291	# default implementation for ->signal
1187		1292
		1293	our $HAVE_ASYNC_INTERRUPT;
1188	our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO);	1294	our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO);
		1295	our (%SIG_ASY, %SIG_ASY_W);
		1296	our ($SIG_COUNT, $SIG_TW);
1189		1297
1190	sub _signal_exec {	1298	sub _signal_exec {
		1299	$HAVE_ASYNC_INTERRUPT
		1300	? $SIGPIPE_R->drain
1191	sysread $SIGPIPE_R, my $dummy, 4;	1301	: sysread $SIGPIPE_R, my $dummy, 9;
1192		1302
1193	while (%SIG_EV) {	1303	while (%SIG_EV) {
1194	for (keys %SIG_EV) {	1304	for (keys %SIG_EV) {
1195	delete $SIG_EV{$_};	1305	delete $SIG_EV{$_};
1196	$_->() for values %{ $SIG_CB{$_} \|\| {} };	1306	$_->() for values %{ $SIG_CB{$_} \|\| {} };
1197	}	1307	}
1198	}	1308	}
1199	}	1309	}
1200		1310
		1311	# install a dumym wakeupw atcher to reduce signal catching latency
		1312	sub _sig_add() {
		1313	unless ($SIG_COUNT++) {
		1314	# try to align timer on a full-second boundary, if possible
		1315	my $NOW = AnyEvent->now;
		1316
		1317	$SIG_TW = AnyEvent->timer (
		1318	after => $MAX_SIGNAL_LATENCY - ($NOW - int $NOW),
		1319	interval => $MAX_SIGNAL_LATENCY,
		1320	cb => sub { }, # just for the PERL_ASYNC_CHECK
		1321	);
		1322	}
		1323	}
		1324
		1325	sub _sig_del {
		1326	undef $SIG_TW
		1327	unless --$SIG_COUNT;
		1328	}
		1329
		1330	sub _signal {
		1331	my (undef, %arg) = @_;
		1332
		1333	my $signal = uc $arg{signal}
		1334	or Carp::croak "required option 'signal' is missing";
		1335
		1336	$SIG_CB{$signal}{$arg{cb}} = $arg{cb};
		1337
		1338	if ($HAVE_ASYNC_INTERRUPT) {
		1339	# async::interrupt
		1340
		1341	$SIG_ASY{$signal} \|\|= do {
		1342	my $asy = new Async::Interrupt
		1343	cb => sub { undef $SIG_EV{$signal} },
		1344	signal => $signal,
		1345	pipe => [$SIGPIPE_R->filenos],
		1346	;
		1347	$asy->pipe_autodrain (0);
		1348
		1349	$asy
		1350	};
		1351
		1352	} else {
		1353	# pure perl
		1354
		1355	$SIG{$signal} \|\|= sub {
		1356	local $!;
		1357	syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;
		1358	undef $SIG_EV{$signal};
		1359	};
		1360
		1361	# can't do signal processing without introducing races in pure perl,
		1362	# so limit the signal latency.
		1363	_sig_add;
		1364	}
		1365
		1366	bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
		1367	}
		1368
1201	sub signal {	1369	sub signal {
1202	my (undef, %arg) = @_;	1370	# probe for availability of Async::Interrupt
		1371	if (!$ENV{PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT} && eval "use Async::Interrupt 0.6 (); 1") {
		1372	warn "AnyEvent: using Async::Interrupt for race-free signal handling.\n" if $VERBOSE >= 8;
1203		1373
1204	unless ($SIGPIPE_R) {	1374	$HAVE_ASYNC_INTERRUPT = 1;
		1375	$SIGPIPE_R = new Async::Interrupt::EventPipe;
		1376	$SIG_IO = AnyEvent->io (fh => $SIGPIPE_R->fileno, poll => "r", cb => \&_signal_exec);
		1377
		1378	} else {
		1379	warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8;
		1380
1205	require Fcntl;	1381	require Fcntl;
1206		1382
1207	if (AnyEvent::WIN32) {	1383	if (AnyEvent::WIN32) {
1208	require AnyEvent::Util;	1384	require AnyEvent::Util;
1209		1385
…		…
1224	or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";	1400	or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";
1225		1401
1226	$SIG_IO = AnyEvent->io (fh => $SIGPIPE_R, poll => "r", cb => \&_signal_exec);	1402	$SIG_IO = AnyEvent->io (fh => $SIGPIPE_R, poll => "r", cb => \&_signal_exec);
1227	}	1403	}
1228		1404
1229	my $signal = uc $arg{signal}	1405	*signal = \&_signal;
1230	or Carp::croak "required option 'signal' is missing";	1406	&signal
1231
1232	$SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1233	$SIG{$signal} \|\|= sub {
1234	local $!;
1235	syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;
1236	undef $SIG_EV{$signal};
1237	};
1238
1239	bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
1240	}	1407	}
1241		1408
1242	sub AnyEvent::Base::signal::DESTROY {	1409	sub AnyEvent::Base::signal::DESTROY {
1243	my ($signal, $cb) = @{$_[0]};	1410	my ($signal, $cb) = @{$_[0]};
1244		1411
		1412	_sig_del;
		1413
1245	delete $SIG_CB{$signal}{$cb};	1414	delete $SIG_CB{$signal}{$cb};
1246		1415
		1416	$HAVE_ASYNC_INTERRUPT
		1417	? delete $SIG_ASY{$signal}
1247	# delete doesn't work with older perls - they then	1418	: # delete doesn't work with older perls - they then
1248	# print weird messages, or just unconditionally exit	1419	# print weird messages, or just unconditionally exit
1249	# instead of getting the default action.	1420	# instead of getting the default action.
		1421	undef $SIG{$signal}
1250	undef $SIG{$signal} unless keys %{ $SIG_CB{$signal} };	1422	unless keys %{ $SIG_CB{$signal} };
1251	}	1423	}
1252		1424
1253	# default implementation for ->child	1425	# default implementation for ->child
1254		1426
1255	our %PID_CB;	1427	our %PID_CB;
1256	our $CHLD_W;	1428	our $CHLD_W;
1257	our $CHLD_DELAY_W;	1429	our $CHLD_DELAY_W;
1258	our $WNOHANG;	1430	our $WNOHANG;
1259		1431
		1432	sub _emit_childstatus($$) {
		1433	my (undef, $rpid, $rstatus) = @_;
		1434
		1435	$_->($rpid, $rstatus)
		1436	for values %{ $PID_CB{$rpid} \|\| {} },
		1437	values %{ $PID_CB{0} \|\| {} };
		1438	}
		1439
1260	sub _sigchld {	1440	sub _sigchld {
		1441	my $pid;
		1442
		1443	AnyEvent->_emit_childstatus ($pid, $?)
1261	while (0 < (my $pid = waitpid -1, $WNOHANG)) {	1444	while ($pid = waitpid -1, $WNOHANG) > 0;
1262	$_->($pid, $?) for (values %{ $PID_CB{$pid} \|\| {} }),
1263	(values %{ $PID_CB{0} \|\| {} });
1264	}
1265	}	1445	}
1266		1446
1267	sub child {	1447	sub child {
1268	my (undef, %arg) = @_;	1448	my (undef, %arg) = @_;
1269		1449
1270	defined (my $pid = $arg{pid} + 0)	1450	defined (my $pid = $arg{pid} + 0)
1271	or Carp::croak "required option 'pid' is missing";	1451	or Carp::croak "required option 'pid' is missing";
1272		1452
1273	$PID_CB{$pid}{$arg{cb}} = $arg{cb};	1453	$PID_CB{$pid}{$arg{cb}} = $arg{cb};
1274		1454
		1455	# WNOHANG is almost cetrainly 1 everywhere
		1456	$WNOHANG \|\|= $^O =~ /^(?:openbsd\|netbsd\|linux\|freebsd\|cygwin\|MSWin32)$/
		1457	? 1
1275	$WNOHANG \|\|= eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } \|\| 1;	1458	: eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } \|\| 1;
1276		1459
1277	unless ($CHLD_W) {	1460	unless ($CHLD_W) {
1278	$CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld);	1461	$CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld);
1279	# child could be a zombie already, so make at least one round	1462	# child could be a zombie already, so make at least one round
1280	&_sigchld;	1463	&_sigchld;
…		…
1332		1515
1333	our @ISA = AnyEvent::CondVar::Base::;	1516	our @ISA = AnyEvent::CondVar::Base::;
1334		1517
1335	package AnyEvent::CondVar::Base;	1518	package AnyEvent::CondVar::Base;
1336		1519
1337	use overload	1520	#use overload
1338	'&{}' => sub { my $self = shift; sub { $self->send (@_) } },	1521	# '&{}' => sub { my $self = shift; sub { $self->send (@_) } },
1339	fallback => 1;	1522	# fallback => 1;
		1523
		1524	# save 300+ kilobytes by dirtily hardcoding overloading
		1525	${"AnyEvent::CondVar::Base::OVERLOAD"}{dummy}++; # Register with magic by touching.
		1526	*{'AnyEvent::CondVar::Base::()'} = sub { }; # "Make it findable via fetchmethod."
		1527	*{'AnyEvent::CondVar::Base::(&{}'} = sub { my $self = shift; sub { $self->send (@_) } }; # &{}
		1528	${'AnyEvent::CondVar::Base::()'} = 1; # fallback
		1529
		1530	our $WAITING;
1340		1531
1341	sub _send {	1532	sub _send {
1342	# nop	1533	# nop
1343	}	1534	}
1344		1535
…		…
1357	sub ready {	1548	sub ready {
1358	$_[0]{_ae_sent}	1549	$_[0]{_ae_sent}
1359	}	1550	}
1360		1551
1361	sub _wait {	1552	sub _wait {
		1553	$WAITING
		1554	and !$_[0]{_ae_sent}
		1555	and Carp::croak "AnyEvent::CondVar: recursive blocking wait detected";
		1556
		1557	local $WAITING = 1;
1362	AnyEvent->one_event while !$_[0]{_ae_sent};	1558	AnyEvent->one_event while !$_[0]{_ae_sent};
1363	}	1559	}
1364		1560
1365	sub recv {	1561	sub recv {
1366	$_[0]->_wait;	1562	$_[0]->_wait;
…		…
1428	C<PERL_ANYEVENT_MODEL>.	1624	C<PERL_ANYEVENT_MODEL>.
1429		1625
1430	When set to C<2> or higher, cause AnyEvent to report to STDERR which event	1626	When set to C<2> or higher, cause AnyEvent to report to STDERR which event
1431	model it chooses.	1627	model it chooses.
1432		1628
		1629	When set to C<8> or higher, then AnyEvent will report extra information on
		1630	which optional modules it loads and how it implements certain features.
		1631
1433	=item C<PERL_ANYEVENT_STRICT>	1632	=item C<PERL_ANYEVENT_STRICT>
1434		1633
1435	AnyEvent does not do much argument checking by default, as thorough	1634	AnyEvent does not do much argument checking by default, as thorough
1436	argument checking is very costly. Setting this variable to a true value	1635	argument checking is very costly. Setting this variable to a true value
1437	will cause AnyEvent to load C<AnyEvent::Strict> and then to thoroughly	1636	will cause AnyEvent to load C<AnyEvent::Strict> and then to thoroughly
1438	check the arguments passed to most method calls. If it finds any problems,	1637	check the arguments passed to most method calls. If it finds any problems,
1439	it will croak.	1638	it will croak.
1440		1639
1441	In other words, enables "strict" mode.	1640	In other words, enables "strict" mode.
1442		1641
1443	Unlike C<use strict>, it is definitely recommended to keep it off in	1642	Unlike C<use strict> (or it's modern cousin, C<< use L<common::sense>
1444	production. Keeping C<PERL_ANYEVENT_STRICT=1> in your environment while	1643	>>, it is definitely recommended to keep it off in production. Keeping
1445	developing programs can be very useful, however.	1644	C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs
		1645	can be very useful, however.
1446		1646
1447	=item C<PERL_ANYEVENT_MODEL>	1647	=item C<PERL_ANYEVENT_MODEL>
1448		1648
1449	This can be used to specify the event model to be used by AnyEvent, before	1649	This can be used to specify the event model to be used by AnyEvent, before
1450	auto detection and -probing kicks in. It must be a string consisting	1650	auto detection and -probing kicks in. It must be a string consisting
…		…
1512		1712
1513	When neither C<ca_file> nor C<ca_path> was specified during	1713	When neither C<ca_file> nor C<ca_path> was specified during
1514	L<AnyEvent::TLS> context creation, and either of these environment	1714	L<AnyEvent::TLS> context creation, and either of these environment
1515	variables exist, they will be used to specify CA certificate locations	1715	variables exist, they will be used to specify CA certificate locations
1516	instead of a system-dependent default.	1716	instead of a system-dependent default.
		1717
		1718	=item C<PERL_ANYEVENT_AVOID_GUARD> and C<PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT>
		1719
		1720	When these are set to C<1>, then the respective modules are not
		1721	loaded. Mostly good for testing AnyEvent itself.
1517		1722
1518	=back	1723	=back
1519		1724
1520	=head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE	1725	=head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE
1521		1726
…		…
2060		2265
2061	A handler for C<SIGCHLD> is installed by AnyEvent's child watcher	2266	A handler for C<SIGCHLD> is installed by AnyEvent's child watcher
2062	emulation for event loops that do not support them natively. Also, some	2267	emulation for event loops that do not support them natively. Also, some
2063	event loops install a similar handler.	2268	event loops install a similar handler.
2064		2269
2065	If, when AnyEvent is loaded, SIGCHLD is set to IGNORE, then AnyEvent will	2270	Additionally, when AnyEvent is loaded and SIGCHLD is set to IGNORE, then
2066	reset it to default, to avoid losing child exit statuses.	2271	AnyEvent will reset it to default, to avoid losing child exit statuses.
2067		2272
2068	=item SIGPIPE	2273	=item SIGPIPE
2069		2274
2070	A no-op handler is installed for C<SIGPIPE> when C<$SIG{PIPE}> is C<undef>	2275	A no-op handler is installed for C<SIGPIPE> when C<$SIG{PIPE}> is C<undef>
2071	when AnyEvent gets loaded.	2276	when AnyEvent gets loaded.
…		…
2089	if $SIG{CHLD} eq 'IGNORE';	2294	if $SIG{CHLD} eq 'IGNORE';
2090		2295
2091	$SIG{PIPE} = sub { }	2296	$SIG{PIPE} = sub { }
2092	unless defined $SIG{PIPE};	2297	unless defined $SIG{PIPE};
2093		2298
		2299	=head1 RECOMMENDED/OPTIONAL MODULES
		2300
		2301	One of AnyEvent's main goals is to be 100% Pure-Perl(tm): only perl (and
		2302	it's built-in modules) are required to use it.
		2303
		2304	That does not mean that AnyEvent won't take advantage of some additional
		2305	modules if they are installed.
		2306
		2307	This section epxlains which additional modules will be used, and how they
		2308	affect AnyEvent's operetion.
		2309
		2310	=over 4
		2311
		2312	=item L<Async::Interrupt>
		2313
		2314	This slightly arcane module is used to implement fast signal handling: To
		2315	my knowledge, there is no way to do completely race-free and quick
		2316	signal handling in pure perl. To ensure that signals still get
		2317	delivered, AnyEvent will start an interval timer to wake up perl (and
		2318	catch the signals) with some delay (default is 10 seconds, look for
		2319	C<$AnyEvent::MAX_SIGNAL_LATENCY>).
		2320
		2321	If this module is available, then it will be used to implement signal
		2322	catching, which means that signals will not be delayed, and the event loop
		2323	will not be interrupted regularly, which is more efficient (And good for
		2324	battery life on laptops).
		2325
		2326	This affects not just the pure-perl event loop, but also other event loops
		2327	that have no signal handling on their own (e.g. Glib, Tk, Qt).
		2328
		2329	Some event loops (POE, Event, Event::Lib) offer signal watchers natively,
		2330	and either employ their own workarounds (POE) or use AnyEvent's workaround
		2331	(using C<$AnyEvent::MAX_SIGNAL_LATENCY>). Installing L<Async::Interrupt>
		2332	does nothing for those backends.
		2333
		2334	=item L<EV>
		2335
		2336	This module isn't really "optional", as it is simply one of the backend
		2337	event loops that AnyEvent can use. However, it is simply the best event
		2338	loop available in terms of features, speed and stability: It supports
		2339	the AnyEvent API optimally, implements all the watcher types in XS, does
		2340	automatic timer adjustments even when no monotonic clock is available,
		2341	can take avdantage of advanced kernel interfaces such as C<epoll> and
		2342	C<kqueue>, and is the fastest backend I<by far>. You can even embed
		2343	L<Glib>/L<Gtk2> in it (or vice versa, see L<EV::Glib> and L<Glib::EV>).
		2344
		2345	=item L<Guard>
		2346
		2347	The guard module, when used, will be used to implement
		2348	C<AnyEvent::Util::guard>. This speeds up guards considerably (and uses a
		2349	lot less memory), but otherwise doesn't affect guard operation much. It is
		2350	purely used for performance.
		2351
		2352	=item L<JSON> and L<JSON::XS>
		2353
		2354	This module is required when you want to read or write JSON data via
		2355	L<AnyEvent::Handle>. It is also written in pure-perl, but can take
		2356	advantage of the ultra-high-speed L<JSON::XS> module when it is installed.
		2357
		2358	In fact, L<AnyEvent::Handle> will use L<JSON::XS> by default if it is
		2359	installed.
		2360
		2361	=item L<Net::SSLeay>
		2362
		2363	Implementing TLS/SSL in Perl is certainly interesting, but not very
		2364	worthwhile: If this module is installed, then L<AnyEvent::Handle> (with
		2365	the help of L<AnyEvent::TLS>), gains the ability to do TLS/SSL.
		2366
		2367	=item L<Time::HiRes>
		2368
		2369	This module is part of perl since release 5.008. It will be used when the
		2370	chosen event library does not come with a timing source on it's own. The
		2371	pure-perl event loop (L<AnyEvent::Impl::Perl>) will additionally use it to
		2372	try to use a monotonic clock for timing stability.
		2373
		2374	=back
		2375
		2376
2094	=head1 FORK	2377	=head1 FORK
2095		2378
2096	Most event libraries are not fork-safe. The ones who are usually are	2379	Most event libraries are not fork-safe. The ones who are usually are
2097	because they rely on inefficient but fork-safe C<select> or C<poll>	2380	because they rely on inefficient but fork-safe C<select> or C<poll>
2098	calls. Only L<EV> is fully fork-aware.	2381	calls. Only L<EV> is fully fork-aware.
2099		2382
2100	If you have to fork, you must either do so I<before> creating your first	2383	If you have to fork, you must either do so I<before> creating your first
2101	watcher OR you must not use AnyEvent at all in the child.	2384	watcher OR you must not use AnyEvent at all in the child OR you must do
		2385	something completely out of the scope of AnyEvent.
2102		2386
2103		2387
2104	=head1 SECURITY CONSIDERATIONS	2388	=head1 SECURITY CONSIDERATIONS
2105		2389
2106	AnyEvent can be forced to load any event model via	2390	AnyEvent can be forced to load any event model via
…		…
2144	L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>.	2428	L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>.
2145		2429
2146	Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>,	2430	Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>,
2147	L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>,	2431	L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>,
2148	L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>,	2432	L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>,
2149	L<AnyEvent::Impl::POE>.	2433	L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>, L<Anyevent::Impl::Irssi>.
2150		2434
2151	Non-blocking file handles, sockets, TCP clients and	2435	Non-blocking file handles, sockets, TCP clients and
2152	servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>.	2436	servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>.
2153		2437
2154	Asynchronous DNS: L<AnyEvent::DNS>.	2438	Asynchronous DNS: L<AnyEvent::DNS>.
2155		2439
2156	Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>,	2440	Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>,
		2441	L<Coro::Event>,
2157		2442
2158	Nontrivial usage examples: L<Net::FCP>, L<Net::XMPP2>, L<AnyEvent::DNS>.	2443	Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::XMPP>,
		2444	L<AnyEvent::HTTP>.
2159		2445
2160		2446
2161	=head1 AUTHOR	2447	=head1 AUTHOR
2162		2448
2163	Marc Lehmann <schmorp@schmorp.de>	2449	Marc Lehmann <schmorp@schmorp.de>

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Comparing AnyEvent/lib/AnyEvent.pm (file contents): Revision 1.228 by root, Wed Jul 8 01:11:12 2009 UTC vs. Revision 1.258 by root, Sun Jul 26 05:57:05 2009 UTC

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Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.228 by root, Wed Jul 8 01:11:12 2009 UTC vs.
Revision 1.258 by root, Sun Jul 26 05:57:05 2009 UTC