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

Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.279 by root, Sun Aug 9 16:05:11 2009 UTC vs.
Revision 1.323 by root, Thu May 20 21:22:20 2010 UTC

…		…
7		7
8	=head1 SYNOPSIS	8	=head1 SYNOPSIS
9		9
10	use AnyEvent;	10	use AnyEvent;
11		11
		12	# if you prefer function calls, look at the AE manpage for
		13	# an alternative API.
		14
12	# file descriptor readable	15	# file handle or descriptor readable
13	my $w = AnyEvent->io (fh => $fh, poll => "r", cb => sub { ... });	16	my $w = AnyEvent->io (fh => $fh, poll => "r", cb => sub { ... });
14		17
15	# one-shot or repeating timers	18	# one-shot or repeating timers
16	my $w = AnyEvent->timer (after => $seconds, cb => sub { ... });	19	my $w = AnyEvent->timer (after => $seconds, cb => sub { ... });
17	my $w = AnyEvent->timer (after => $seconds, interval => $seconds, cb => ...	20	my $w = AnyEvent->timer (after => $seconds, interval => $seconds, cb => ...
…		…
363	might affect timers and time-outs.	366	might affect timers and time-outs.
364		367
365	When this is the case, you can call this method, which will update the	368	When this is the case, you can call this method, which will update the
366	event loop's idea of "current time".	369	event loop's idea of "current time".
367		370
		371	A typical example would be a script in a web server (e.g. C<mod_perl>) -
		372	when mod_perl executes the script, then the event loop will have the wrong
		373	idea about the "current time" (being potentially far in the past, when the
		374	script ran the last time). In that case you should arrange a call to C<<
		375	AnyEvent->now_update >> each time the web server process wakes up again
		376	(e.g. at the start of your script, or in a handler).
		377
368	Note that updating the time I<might> cause some events to be handled.	378	Note that updating the time I<might> cause some events to be handled.
369		379
370	=back	380	=back
371		381
372	=head2 SIGNAL WATCHERS	382	=head2 SIGNAL WATCHERS
…		…
395	correctly.	405	correctly.
396		406
397	Example: exit on SIGINT	407	Example: exit on SIGINT
398		408
399	my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });	409	my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });
		410
		411	=head3 Restart Behaviour
		412
		413	While restart behaviour is up to the event loop implementation, most will
		414	not restart syscalls (that includes L<Async::Interrupt> and AnyEvent's
		415	pure perl implementation).
		416
		417	=head3 Safe/Unsafe Signals
		418
		419	Perl signals can be either "safe" (synchronous to opcode handling) or
		420	"unsafe" (asynchronous) - the former might get delayed indefinitely, the
		421	latter might corrupt your memory.
		422
		423	AnyEvent signal handlers are, in addition, synchronous to the event loop,
		424	i.e. they will not interrupt your running perl program but will only be
		425	called as part of the normal event handling (just like timer, I/O etc.
		426	callbacks, too).
400		427
401	=head3 Signal Races, Delays and Workarounds	428	=head3 Signal Races, Delays and Workarounds
402		429
403	Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching	430	Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching
404	callbacks to signals in a generic way, which is a pity, as you cannot	431	callbacks to signals in a generic way, which is a pity, as you cannot
…		…
479		506
480	=head2 IDLE WATCHERS	507	=head2 IDLE WATCHERS
481		508
482	$w = AnyEvent->idle (cb => <callback>);	509	$w = AnyEvent->idle (cb => <callback>);
483		510
484	Sometimes there is a need to do something, but it is not so important	511	Repeatedly invoke the callback after the process becomes idle, until
485	to do it instantly, but only when there is nothing better to do. This	512	either the watcher is destroyed or new events have been detected.
486	"nothing better to do" is usually defined to be "no other events need
487	attention by the event loop".
488		513
489	Idle watchers ideally get invoked when the event loop has nothing	514	Idle watchers are useful when there is a need to do something, but it
490	better to do, just before it would block the process to wait for new	515	is not so important (or wise) to do it instantly. The callback will be
491	events. Instead of blocking, the idle watcher is invoked.	516	invoked only when there is "nothing better to do", which is usually
		517	defined as "all outstanding events have been handled and no new events
		518	have been detected". That means that idle watchers ideally get invoked
		519	when the event loop has just polled for new events but none have been
		520	detected. Instead of blocking to wait for more events, the idle watchers
		521	will be invoked.
492		522
493	Most event loops unfortunately do not really support idle watchers (only	523	Unfortunately, most event loops do not really support idle watchers (only
494	EV, Event and Glib do it in a usable fashion) - for the rest, AnyEvent	524	EV, Event and Glib do it in a usable fashion) - for the rest, AnyEvent
495	will simply call the callback "from time to time".	525	will simply call the callback "from time to time".
496		526
497	Example: read lines from STDIN, but only process them when the	527	Example: read lines from STDIN, but only process them when the
498	program is otherwise idle:	528	program is otherwise idle:
…		…
579	eventually calls C<< -> send >>, and the "consumer side", which waits	609	eventually calls C<< -> send >>, and the "consumer side", which waits
580	for the send to occur.	610	for the send to occur.
581		611
582	Example: wait for a timer.	612	Example: wait for a timer.
583		613
584	# wait till the result is ready	614	# condition: "wait till the timer is fired"
585	my $result_ready = AnyEvent->condvar;	615	my $timer_fired = AnyEvent->condvar;
586		616
587	# do something such as adding a timer	617	# create the timer - we could wait for, say
588	# or socket watcher the calls $result_ready->send	618	# a handle becomign ready, or even an
589	# when the "result" is ready.	619	# AnyEvent::HTTP request to finish, but
590	# in this case, we simply use a timer:	620	# in this case, we simply use a timer:
591	my $w = AnyEvent->timer (	621	my $w = AnyEvent->timer (
592	after => 1,	622	after => 1,
593	cb => sub { $result_ready->send },	623	cb => sub { $timer_fired->send },
594	);	624	);
595		625
596	# this "blocks" (while handling events) till the callback	626	# this "blocks" (while handling events) till the callback
597	# calls -<send	627	# calls ->send
598	$result_ready->recv;	628	$timer_fired->recv;
599		629
600	Example: wait for a timer, but take advantage of the fact that condition	630	Example: wait for a timer, but take advantage of the fact that condition
601	variables are also callable directly.	631	variables are also callable directly.
602		632
603	my $done = AnyEvent->condvar;	633	my $done = AnyEvent->condvar;
…		…
666	one. For example, a function that pings many hosts in parallel might want	696	one. For example, a function that pings many hosts in parallel might want
667	to use a condition variable for the whole process.	697	to use a condition variable for the whole process.
668		698
669	Every call to C<< ->begin >> will increment a counter, and every call to	699	Every call to C<< ->begin >> will increment a counter, and every call to
670	C<< ->end >> will decrement it. If the counter reaches C<0> in C<< ->end	700	C<< ->end >> will decrement it. If the counter reaches C<0> in C<< ->end
671	>>, the (last) callback passed to C<begin> will be executed. That callback	701	>>, the (last) callback passed to C<begin> will be executed, passing the
672	is I<supposed> to call C<< ->send >>, but that is not required. If no	702	condvar as first argument. That callback is I<supposed> to call C<< ->send
673	callback was set, C<send> will be called without any arguments.	703	>>, but that is not required. If no group callback was set, C<send> will
		704	be called without any arguments.
674		705
675	You can think of C<< $cv->send >> giving you an OR condition (one call	706	You can think of C<< $cv->send >> giving you an OR condition (one call
676	sends), while C<< $cv->begin >> and C<< $cv->end >> giving you an AND	707	sends), while C<< $cv->begin >> and C<< $cv->end >> giving you an AND
677	condition (all C<begin> calls must be C<end>'ed before the condvar sends).	708	condition (all C<begin> calls must be C<end>'ed before the condvar sends).
678		709
…		…
705	begung can potentially be zero:	736	begung can potentially be zero:
706		737
707	my $cv = AnyEvent->condvar;	738	my $cv = AnyEvent->condvar;
708		739
709	my %result;	740	my %result;
710	$cv->begin (sub { $cv->send (\%result) });	741	$cv->begin (sub { shift->send (\%result) });
711		742
712	for my $host (@list_of_hosts) {	743	for my $host (@list_of_hosts) {
713	$cv->begin;	744	$cv->begin;
714	ping_host_then_call_callback $host, sub {	745	ping_host_then_call_callback $host, sub {
715	$result{$host} = ...;	746	$result{$host} = ...;
…		…
941	You should check C<$AnyEvent::MODEL> before adding to this array, though:	972	You should check C<$AnyEvent::MODEL> before adding to this array, though:
942	if it is defined then the event loop has already been detected, and the	973	if it is defined then the event loop has already been detected, and the
943	array will be ignored.	974	array will be ignored.
944		975
945	Best use C<AnyEvent::post_detect { BLOCK }> when your application allows	976	Best use C<AnyEvent::post_detect { BLOCK }> when your application allows
946	it,as it takes care of these details.	977	it, as it takes care of these details.
947		978
948	This variable is mainly useful for modules that can do something useful	979	This variable is mainly useful for modules that can do something useful
949	when AnyEvent is used and thus want to know when it is initialised, but do	980	when AnyEvent is used and thus want to know when it is initialised, but do
950	not need to even load it by default. This array provides the means to hook	981	not need to even load it by default. This array provides the means to hook
951	into AnyEvent passively, without loading it.	982	into AnyEvent passively, without loading it.
		983
		984	Example: To load Coro::AnyEvent whenever Coro and AnyEvent are used
		985	together, you could put this into Coro (this is the actual code used by
		986	Coro to accomplish this):
		987
		988	if (defined $AnyEvent::MODEL) {
		989	# AnyEvent already initialised, so load Coro::AnyEvent
		990	require Coro::AnyEvent;
		991	} else {
		992	# AnyEvent not yet initialised, so make sure to load Coro::AnyEvent
		993	# as soon as it is
		994	push @AnyEvent::post_detect, sub { require Coro::AnyEvent };
		995	}
952		996
953	=back	997	=back
954		998
955	=head1 WHAT TO DO IN A MODULE	999	=head1 WHAT TO DO IN A MODULE
956		1000
…		…
1038		1082
1039	=item L<AnyEvent::DNS>	1083	=item L<AnyEvent::DNS>
1040		1084
1041	Provides rich asynchronous DNS resolver capabilities.	1085	Provides rich asynchronous DNS resolver capabilities.
1042		1086
		1087	=item L<AnyEvent::HTTP>, L<AnyEvent::IRC>, L<AnyEvent::XMPP>, L<AnyEvent::GPSD>, L<AnyEvent::IGS>, L<AnyEvent::FCP>
		1088
		1089	Implement event-based interfaces to the protocols of the same name (for
		1090	the curious, IGS is the International Go Server and FCP is the Freenet
		1091	Client Protocol).
		1092
		1093	=item L<AnyEvent::Handle::UDP>
		1094
		1095	Here be danger!
		1096
		1097	As Pauli would put it, "Not only is it not right, it's not even wrong!" -
		1098	there are so many things wrong with AnyEvent::Handle::UDP, most notably
		1099	it's use of a stream-based API with a protocol that isn't streamable, that
		1100	the only way to improve it is to delete it.
		1101
		1102	It features data corruption (but typically only under load) and general
		1103	confusion. On top, the author is not only clueless about UDP but also
		1104	fact-resistant - some gems of his understanding: "connect doesn't work
		1105	with UDP", "UDP packets are not IP packets", "UDP only has datagrams, not
		1106	packets", "I don't need to implement proper error checking as UDP doesn't
		1107	support error checking" and so on - he doesn't even understand what's
		1108	wrong with his module when it is explained to him.
		1109
1043	=item L<AnyEvent::HTTP>	1110	=item L<AnyEvent::DBI>
1044		1111
1045	A simple-to-use HTTP library that is capable of making a lot of concurrent	1112	Executes L<DBI> requests asynchronously in a proxy process for you,
1046	HTTP requests.	1113	notifying you in an event-bnased way when the operation is finished.
		1114
		1115	=item L<AnyEvent::AIO>
		1116
		1117	Truly asynchronous (as opposed to non-blocking) I/O, should be in the
		1118	toolbox of every event programmer. AnyEvent::AIO transparently fuses
		1119	L<IO::AIO> and AnyEvent together, giving AnyEvent access to event-based
		1120	file I/O, and much more.
1047		1121
1048	=item L<AnyEvent::HTTPD>	1122	=item L<AnyEvent::HTTPD>
1049		1123
1050	Provides a simple web application server framework.	1124	A simple embedded webserver.
1051		1125
1052	=item L<AnyEvent::FastPing>	1126	=item L<AnyEvent::FastPing>
1053		1127
1054	The fastest ping in the west.	1128	The fastest ping in the west.
1055
1056	=item L<AnyEvent::DBI>
1057
1058	Executes L<DBI> requests asynchronously in a proxy process.
1059
1060	=item L<AnyEvent::AIO>
1061
1062	Truly asynchronous I/O, should be in the toolbox of every event
1063	programmer. AnyEvent::AIO transparently fuses L<IO::AIO> and AnyEvent
1064	together.
1065
1066	=item L<AnyEvent::BDB>
1067
1068	Truly asynchronous Berkeley DB access. AnyEvent::BDB transparently fuses
1069	L<BDB> and AnyEvent together.
1070
1071	=item L<AnyEvent::GPSD>
1072
1073	A non-blocking interface to gpsd, a daemon delivering GPS information.
1074
1075	=item L<AnyEvent::IRC>
1076
1077	AnyEvent based IRC client module family (replacing the older Net::IRC3).
1078
1079	=item L<AnyEvent::XMPP>
1080
1081	AnyEvent based XMPP (Jabber protocol) module family (replacing the older
1082	Net::XMPP2>.
1083
1084	=item L<AnyEvent::IGS>
1085
1086	A non-blocking interface to the Internet Go Server protocol (used by
1087	L<App::IGS>).
1088
1089	=item L<Net::FCP>
1090
1091	AnyEvent-based implementation of the Freenet Client Protocol, birthplace
1092	of AnyEvent.
1093
1094	=item L<Event::ExecFlow>
1095
1096	High level API for event-based execution flow control.
1097		1129
1098	=item L<Coro>	1130	=item L<Coro>
1099		1131
1100	Has special support for AnyEvent via L<Coro::AnyEvent>.	1132	Has special support for AnyEvent via L<Coro::AnyEvent>.
1101		1133
…		…
1105		1137
1106	package AnyEvent;	1138	package AnyEvent;
1107		1139
1108	# basically a tuned-down version of common::sense	1140	# basically a tuned-down version of common::sense
1109	sub common_sense {	1141	sub common_sense {
1110	# no warnings	1142	# from common:.sense 1.0
1111	${^WARNING_BITS} ^= ${^WARNING_BITS};	1143	${^WARNING_BITS} = "\xfc\x3f\x33\x00\x0f\xf3\xcf\xc0\xf3\xfc\x33\x00";
1112	# use strict vars subs	1144	# use strict vars subs - NO UTF-8, as Util.pm doesn't like this atm. (uts46data.pl)
1113	$^H \|= 0x00000600;	1145	$^H \|= 0x00000600;
1114	}	1146	}
1115		1147
1116	BEGIN { AnyEvent::common_sense }	1148	BEGIN { AnyEvent::common_sense }
1117		1149
1118	use Carp ();	1150	use Carp ();
1119		1151
1120	our $VERSION = '5.0';	1152	our $VERSION = '5.261';
1121	our $MODEL;	1153	our $MODEL;
1122		1154
1123	our $AUTOLOAD;	1155	our $AUTOLOAD;
1124	our @ISA;	1156	our @ISA;
1125		1157
1126	our @REGISTRY;	1158	our @REGISTRY;
1127		1159
1128	our $WIN32;
1129
1130	our $VERBOSE;	1160	our $VERBOSE;
1131		1161
1132	BEGIN {	1162	BEGIN {
1133	eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }";	1163	require "AnyEvent/constants.pl";
		1164
1134	eval "sub TAINT(){ " . (${^TAINT}*1) . " }";	1165	eval "sub TAINT (){" . (${^TAINT}*1) . "}";
1135		1166
1136	delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}	1167	delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}
1137	if ${^TAINT};	1168	if ${^TAINT};
1138		1169
1139	$VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1;	1170	$VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1;
…		…
1182	our @post_detect;	1213	our @post_detect;
1183		1214
1184	sub post_detect(&) {	1215	sub post_detect(&) {
1185	my ($cb) = @_;	1216	my ($cb) = @_;
1186		1217
1187	if ($MODEL) {
1188	$cb->();
1189
1190	undef
1191	} else {
1192	push @post_detect, $cb;	1218	push @post_detect, $cb;
1193		1219
1194	defined wantarray	1220	defined wantarray
1195	? bless \$cb, "AnyEvent::Util::postdetect"	1221	? bless \$cb, "AnyEvent::Util::postdetect"
1196	: ()	1222	: ()
1197	}
1198	}	1223	}
1199		1224
1200	sub AnyEvent::Util::postdetect::DESTROY {	1225	sub AnyEvent::Util::postdetect::DESTROY {
1201	@post_detect = grep $_ != ${$_[0]}, @post_detect;	1226	@post_detect = grep $_ != ${$_[0]}, @post_detect;
1202	}	1227	}
1203		1228
1204	sub detect() {	1229	sub detect() {
		1230	# free some memory
		1231	*detect = sub () { $MODEL };
		1232
		1233	local $!; # for good measure
		1234	local $SIG{__DIE__};
		1235
		1236	if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) {
		1237	my $model = "AnyEvent::Impl::$1";
		1238	if (eval "require $model") {
		1239	$MODEL = $model;
		1240	warn "AnyEvent: loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.\n" if $VERBOSE >= 2;
		1241	} else {
		1242	warn "AnyEvent: unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@" if $VERBOSE;
		1243	}
		1244	}
		1245
		1246	# check for already loaded models
1205	unless ($MODEL) {	1247	unless ($MODEL) {
1206	local $SIG{__DIE__};	1248	for (@REGISTRY, @models) {
1207		1249	my ($package, $model) = @$_;
1208	if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) {	1250	if (${"$package\::VERSION"} > 0) {
1209	my $model = "AnyEvent::Impl::$1";
1210	if (eval "require $model") {	1251	if (eval "require $model") {
1211	$MODEL = $model;	1252	$MODEL = $model;
1212	warn "AnyEvent: loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.\n" if $VERBOSE >= 2;	1253	warn "AnyEvent: autodetected model '$model', using it.\n" if $VERBOSE >= 2;
1213	} else {	1254	last;
1214	warn "AnyEvent: unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@" if $VERBOSE;	1255	}
1215	}	1256	}
1216	}	1257	}
1217		1258
1218	# check for already loaded models
1219	unless ($MODEL) {	1259	unless ($MODEL) {
		1260	# try to autoload a model
1220	for (@REGISTRY, @models) {	1261	for (@REGISTRY, @models) {
1221	my ($package, $model) = @$_;	1262	my ($package, $model, $autoload) = @$_;
		1263	if (
		1264	$autoload
		1265	and eval "require $package"
1222	if (${"$package\::VERSION"} > 0) {	1266	and ${"$package\::VERSION"} > 0
1223	if (eval "require $model") {	1267	and eval "require $model"
		1268	) {
1224	$MODEL = $model;	1269	$MODEL = $model;
1225	warn "AnyEvent: autodetected model '$model', using it.\n" if $VERBOSE >= 2;	1270	warn "AnyEvent: autoloaded model '$model', using it.\n" if $VERBOSE >= 2;
1226	last;	1271	last;
1227	}
1228	}	1272	}
1229	}	1273	}
1230		1274
1231	unless ($MODEL) {
1232	# try to autoload a model
1233	for (@REGISTRY, @models) {
1234	my ($package, $model, $autoload) = @$_;
1235	if (
1236	$autoload
1237	and eval "require $package"
1238	and ${"$package\::VERSION"} > 0
1239	and eval "require $model"
1240	) {
1241	$MODEL = $model;
1242	warn "AnyEvent: autoloaded model '$model', using it.\n" if $VERBOSE >= 2;
1243	last;
1244	}
1245	}
1246
1247	$MODEL	1275	$MODEL
1248	or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib.\n";	1276	or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib.\n";
1249	}
1250	}	1277	}
1251
1252	push @{"$MODEL\::ISA"}, "AnyEvent::Base";
1253
1254	unshift @ISA, $MODEL;
1255
1256	require AnyEvent::Strict if $ENV{PERL_ANYEVENT_STRICT};
1257
1258	(shift @post_detect)->() while @post_detect;
1259	}	1278	}
		1279
		1280	@models = (); # free probe data
		1281
		1282	push @{"$MODEL\::ISA"}, "AnyEvent::Base";
		1283	unshift @ISA, $MODEL;
		1284
		1285	# now nuke some methods that are overriden by the backend.
		1286	# SUPER is not allowed.
		1287	for (qw(time signal child idle)) {
		1288	undef &{"AnyEvent::Base::$_"}
		1289	if defined &{"$MODEL\::$_"};
		1290	}
		1291
		1292	require AnyEvent::Strict if $ENV{PERL_ANYEVENT_STRICT};
		1293
		1294	(shift @post_detect)->() while @post_detect;
		1295
		1296	*post_detect = sub(&) {
		1297	shift->();
		1298
		1299	undef
		1300	};
1260		1301
1261	$MODEL	1302	$MODEL
1262	}	1303	}
1263		1304
1264	sub AUTOLOAD {	1305	sub AUTOLOAD {
1265	(my $func = $AUTOLOAD) =~ s/.*://;	1306	(my $func = $AUTOLOAD) =~ s/.*://;
1266		1307
1267	$method{$func}	1308	$method{$func}
1268	or Carp::croak "$func: not a valid method for AnyEvent objects";	1309	or Carp::croak "$func: not a valid AnyEvent class method";
1269		1310
1270	detect unless $MODEL;	1311	detect;
1271		1312
1272	my $class = shift;	1313	my $class = shift;
1273	$class->$func (@_);	1314	$class->$func (@_);
1274	}	1315	}
1275		1316
…		…
1292		1333
1293	=head1 SIMPLIFIED AE API	1334	=head1 SIMPLIFIED AE API
1294		1335
1295	Starting with version 5.0, AnyEvent officially supports a second, much	1336	Starting with version 5.0, AnyEvent officially supports a second, much
1296	simpler, API that is designed to reduce the calling, typing and memory	1337	simpler, API that is designed to reduce the calling, typing and memory
1297	overhead.	1338	overhead by using function call syntax and a fixed number of parameters.
1298		1339
1299	See the L<AE> manpage for details.	1340	See the L<AE> manpage for details.
1300		1341
1301	=cut	1342	=cut
1302		1343
1303	package AE;	1344	package AE;
1304		1345
1305	our $VERSION = $AnyEvent::VERSION;	1346	our $VERSION = $AnyEvent::VERSION;
		1347
		1348	# fall back to the main API by default - backends and AnyEvent::Base
		1349	# implementations can overwrite these.
1306		1350
1307	sub io($$$) {	1351	sub io($$$) {
1308	AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2])	1352	AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2])
1309	}	1353	}
1310		1354
…		…
1342		1386
1343	package AnyEvent::Base;	1387	package AnyEvent::Base;
1344		1388
1345	# default implementations for many methods	1389	# default implementations for many methods
1346		1390
1347	sub _time {	1391	sub time {
		1392	eval q{ # poor man's autoloading {}
1348	# probe for availability of Time::HiRes	1393	# probe for availability of Time::HiRes
1349	if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {	1394	if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {
1350	warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8;	1395	warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8;
1351	*_time = \&Time::HiRes::time;	1396	*AE::time = \&Time::HiRes::time;
1352	# if (eval "use POSIX (); (POSIX::times())...	1397	# if (eval "use POSIX (); (POSIX::times())...
1353	} else {	1398	} else {
1354	warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE;	1399	warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE;
1355	*_time = sub { time }; # epic fail	1400	*AE::time = sub (){ time }; # epic fail
		1401	}
		1402
		1403	*time = sub { AE::time }; # different prototypes
1356	}	1404	};
		1405	die if $@;
1357		1406
1358	&_time	1407	&time
1359	}	1408	}
1360		1409
1361	sub time { _time }	1410	*now = \&time;
1362	sub now { _time }	1411
1363	sub now_update { }	1412	sub now_update { }
1364		1413
1365	# default implementation for ->condvar	1414	# default implementation for ->condvar
1366		1415
1367	sub condvar {	1416	sub condvar {
		1417	eval q{ # poor man's autoloading {}
		1418	*condvar = sub {
1368	bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"	1419	bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"
		1420	};
		1421
		1422	*AE::cv = sub (;&) {
		1423	bless { @_ ? (_ae_cb => shift) : () }, "AnyEvent::CondVar"
		1424	};
		1425	};
		1426	die if $@;
		1427
		1428	&condvar
1369	}	1429	}
1370		1430
1371	# default implementation for ->signal	1431	# default implementation for ->signal
1372		1432
1373	our $HAVE_ASYNC_INTERRUPT;	1433	our $HAVE_ASYNC_INTERRUPT;
1374		1434
1375	sub _have_async_interrupt() {	1435	sub _have_async_interrupt() {
1376	$HAVE_ASYNC_INTERRUPT = 1*(!$ENV{PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT}	1436	$HAVE_ASYNC_INTERRUPT = 1*(!$ENV{PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT}
1377	&& eval "use Async::Interrupt 1.0 (); 1")	1437	&& eval "use Async::Interrupt 1.02 (); 1")
1378	unless defined $HAVE_ASYNC_INTERRUPT;	1438	unless defined $HAVE_ASYNC_INTERRUPT;
1379		1439
1380	$HAVE_ASYNC_INTERRUPT	1440	$HAVE_ASYNC_INTERRUPT
1381	}	1441	}
1382		1442
1383	our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO);	1443	our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO);
1384	our (%SIG_ASY, %SIG_ASY_W);	1444	our (%SIG_ASY, %SIG_ASY_W);
1385	our ($SIG_COUNT, $SIG_TW);	1445	our ($SIG_COUNT, $SIG_TW);
1386		1446
1387	sub _signal_exec {
1388	$HAVE_ASYNC_INTERRUPT
1389	? $SIGPIPE_R->drain
1390	: sysread $SIGPIPE_R, my $dummy, 9;
1391
1392	while (%SIG_EV) {
1393	for (keys %SIG_EV) {
1394	delete $SIG_EV{$_};
1395	$_->() for values %{ $SIG_CB{$_} \|\| {} };
1396	}
1397	}
1398	}
1399
1400	# install a dummy wakeup watcher to reduce signal catching latency	1447	# install a dummy wakeup watcher to reduce signal catching latency
		1448	# used by Impls
1401	sub _sig_add() {	1449	sub _sig_add() {
1402	unless ($SIG_COUNT++) {	1450	unless ($SIG_COUNT++) {
1403	# try to align timer on a full-second boundary, if possible	1451	# try to align timer on a full-second boundary, if possible
1404	my $NOW = AE::now;	1452	my $NOW = AE::now;
1405		1453
…		…
1415	undef $SIG_TW	1463	undef $SIG_TW
1416	unless --$SIG_COUNT;	1464	unless --$SIG_COUNT;
1417	}	1465	}
1418		1466
1419	our $_sig_name_init; $_sig_name_init = sub {	1467	our $_sig_name_init; $_sig_name_init = sub {
1420	eval q{ # poor man's autoloading	1468	eval q{ # poor man's autoloading {}
1421	undef $_sig_name_init;	1469	undef $_sig_name_init;
1422		1470
1423	if (_have_async_interrupt) {	1471	if (_have_async_interrupt) {
1424	*sig2num = \&Async::Interrupt::sig2num;	1472	*sig2num = \&Async::Interrupt::sig2num;
1425	*sig2name = \&Async::Interrupt::sig2name;	1473	*sig2name = \&Async::Interrupt::sig2name;
…		…
1457	$SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec;	1505	$SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec;
1458		1506
1459	} else {	1507	} else {
1460	warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8;	1508	warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8;
1461		1509
1462	require Fcntl;
1463
1464	if (AnyEvent::WIN32) {	1510	if (AnyEvent::WIN32) {
1465	require AnyEvent::Util;	1511	require AnyEvent::Util;
1466		1512
1467	($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();	1513	($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
1468	AnyEvent::Util::fh_nonblocking ($SIGPIPE_R, 1) if $SIGPIPE_R;	1514	AnyEvent::Util::fh_nonblocking ($SIGPIPE_R, 1) if $SIGPIPE_R;
1469	AnyEvent::Util::fh_nonblocking ($SIGPIPE_W, 1) if $SIGPIPE_W; # just in case	1515	AnyEvent::Util::fh_nonblocking ($SIGPIPE_W, 1) if $SIGPIPE_W; # just in case
1470	} else {	1516	} else {
1471	pipe $SIGPIPE_R, $SIGPIPE_W;	1517	pipe $SIGPIPE_R, $SIGPIPE_W;
1472	fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R;	1518	fcntl $SIGPIPE_R, AnyEvent::F_SETFL, AnyEvent::O_NONBLOCK if $SIGPIPE_R;
1473	fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case	1519	fcntl $SIGPIPE_W, AnyEvent::F_SETFL, AnyEvent::O_NONBLOCK if $SIGPIPE_W; # just in case
1474		1520
1475	# not strictly required, as $^F is normally 2, but let's make sure...	1521	# not strictly required, as $^F is normally 2, but let's make sure...
1476	fcntl $SIGPIPE_R, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;	1522	fcntl $SIGPIPE_R, AnyEvent::F_SETFD, AnyEvent::FD_CLOEXEC;
1477	fcntl $SIGPIPE_W, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;	1523	fcntl $SIGPIPE_W, AnyEvent::F_SETFD, AnyEvent::FD_CLOEXEC;
1478	}	1524	}
1479		1525
1480	$SIGPIPE_R	1526	$SIGPIPE_R
1481	or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";	1527	or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";
1482		1528
1483	$SIG_IO = AE::io $SIGPIPE_R, 0, \&_signal_exec;	1529	$SIG_IO = AE::io $SIGPIPE_R, 0, \&_signal_exec;
1484	}	1530	}
1485		1531
1486	*signal = sub {	1532	*signal = $HAVE_ASYNC_INTERRUPT
		1533	? sub {
1487	my (undef, %arg) = @_;	1534	my (undef, %arg) = @_;
1488		1535
1489	my $signal = uc $arg{signal}
1490	or Carp::croak "required option 'signal' is missing";
1491
1492	if ($HAVE_ASYNC_INTERRUPT) {
1493	# async::interrupt	1536	# async::interrupt
1494
1495	$signal = sig2num $signal;	1537	my $signal = sig2num $arg{signal};
1496	$SIG_CB{$signal}{$arg{cb}} = $arg{cb};	1538	$SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1497		1539
1498	$SIG_ASY{$signal} \|\|= new Async::Interrupt	1540	$SIG_ASY{$signal} \|\|= new Async::Interrupt
1499	cb => sub { undef $SIG_EV{$signal} },	1541	cb => sub { undef $SIG_EV{$signal} },
1500	signal => $signal,	1542	signal => $signal,
1501	pipe => [$SIGPIPE_R->filenos],	1543	pipe => [$SIGPIPE_R->filenos],
1502	pipe_autodrain => 0,	1544	pipe_autodrain => 0,
1503	;	1545	;
1504		1546
1505	} else {	1547	bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
		1548	}
		1549	: sub {
		1550	my (undef, %arg) = @_;
		1551
1506	# pure perl	1552	# pure perl
1507
1508	# AE::Util has been loaded in signal
1509	$signal = sig2name $signal;	1553	my $signal = sig2name $arg{signal};
1510	$SIG_CB{$signal}{$arg{cb}} = $arg{cb};	1554	$SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1511		1555
1512	$SIG{$signal} \|\|= sub {	1556	$SIG{$signal} \|\|= sub {
1513	local $!;	1557	local $!;
1514	syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;	1558	syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;
1515	undef $SIG_EV{$signal};	1559	undef $SIG_EV{$signal};
1516	};	1560	};
1517		1561
1518	# can't do signal processing without introducing races in pure perl,	1562	# can't do signal processing without introducing races in pure perl,
1519	# so limit the signal latency.	1563	# so limit the signal latency.
1520	_sig_add;	1564	_sig_add;
1521	}
1522		1565
1523	bless [$signal, $arg{cb}], "AnyEvent::Base::signal"	1566	bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
		1567	}
1524	};	1568	;
1525		1569
1526	*AnyEvent::Base::signal::DESTROY = sub {	1570	*AnyEvent::Base::signal::DESTROY = sub {
1527	my ($signal, $cb) = @{$_[0]};	1571	my ($signal, $cb) = @{$_[0]};
1528		1572
1529	_sig_del;	1573	_sig_del;
…		…
1536	# print weird messages, or just unconditionally exit	1580	# print weird messages, or just unconditionally exit
1537	# instead of getting the default action.	1581	# instead of getting the default action.
1538	undef $SIG{$signal}	1582	undef $SIG{$signal}
1539	unless keys %{ $SIG_CB{$signal} };	1583	unless keys %{ $SIG_CB{$signal} };
1540	};	1584	};
		1585
		1586	*_signal_exec = sub {
		1587	$HAVE_ASYNC_INTERRUPT
		1588	? $SIGPIPE_R->drain
		1589	: sysread $SIGPIPE_R, (my $dummy), 9;
		1590
		1591	while (%SIG_EV) {
		1592	for (keys %SIG_EV) {
		1593	delete $SIG_EV{$_};
		1594	$_->() for values %{ $SIG_CB{$_} \|\| {} };
		1595	}
		1596	}
		1597	};
1541	};	1598	};
1542	die if $@;	1599	die if $@;
		1600
1543	&signal	1601	&signal
1544	}	1602	}
1545		1603
1546	# default implementation for ->child	1604	# default implementation for ->child
1547		1605
1548	our %PID_CB;	1606	our %PID_CB;
1549	our $CHLD_W;	1607	our $CHLD_W;
1550	our $CHLD_DELAY_W;	1608	our $CHLD_DELAY_W;
1551	our $WNOHANG;	1609	our $WNOHANG;
1552		1610
		1611	# used by many Impl's
1553	sub _emit_childstatus($$) {	1612	sub _emit_childstatus($$) {
1554	my (undef, $rpid, $rstatus) = @_;	1613	my (undef, $rpid, $rstatus) = @_;
1555		1614
1556	$_->($rpid, $rstatus)	1615	$_->($rpid, $rstatus)
1557	for values %{ $PID_CB{$rpid} \|\| {} },	1616	for values %{ $PID_CB{$rpid} \|\| {} },
1558	values %{ $PID_CB{0} \|\| {} };	1617	values %{ $PID_CB{0} \|\| {} };
1559	}	1618	}
1560		1619
1561	sub _sigchld {
1562	my $pid;
1563
1564	AnyEvent->_emit_childstatus ($pid, $?)
1565	while ($pid = waitpid -1, $WNOHANG) > 0;
1566	}
1567
1568	sub child {	1620	sub child {
		1621	eval q{ # poor man's autoloading {}
		1622	*_sigchld = sub {
		1623	my $pid;
		1624
		1625	AnyEvent->_emit_childstatus ($pid, $?)
		1626	while ($pid = waitpid -1, $WNOHANG) > 0;
		1627	};
		1628
		1629	*child = sub {
1569	my (undef, %arg) = @_;	1630	my (undef, %arg) = @_;
1570		1631
1571	defined (my $pid = $arg{pid} + 0)	1632	defined (my $pid = $arg{pid} + 0)
1572	or Carp::croak "required option 'pid' is missing";	1633	or Carp::croak "required option 'pid' is missing";
1573		1634
1574	$PID_CB{$pid}{$arg{cb}} = $arg{cb};	1635	$PID_CB{$pid}{$arg{cb}} = $arg{cb};
1575		1636
1576	# WNOHANG is almost cetrainly 1 everywhere	1637	# WNOHANG is almost cetrainly 1 everywhere
1577	$WNOHANG \|\|= $^O =~ /^(?:openbsd\|netbsd\|linux\|freebsd\|cygwin\|MSWin32)$/	1638	$WNOHANG \|\|= $^O =~ /^(?:openbsd\|netbsd\|linux\|freebsd\|cygwin\|MSWin32)$/
1578	? 1	1639	? 1
1579	: eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } \|\| 1;	1640	: eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } \|\| 1;
1580		1641
1581	unless ($CHLD_W) {	1642	unless ($CHLD_W) {
1582	$CHLD_W = AE::signal CHLD => \&_sigchld;	1643	$CHLD_W = AE::signal CHLD => \&_sigchld;
1583	# child could be a zombie already, so make at least one round	1644	# child could be a zombie already, so make at least one round
1584	&_sigchld;	1645	&_sigchld;
1585	}	1646	}
1586		1647
1587	bless [$pid, $arg{cb}], "AnyEvent::Base::child"	1648	bless [$pid, $arg{cb}], "AnyEvent::Base::child"
1588	}	1649	};
1589		1650
1590	sub AnyEvent::Base::child::DESTROY {	1651	*AnyEvent::Base::child::DESTROY = sub {
1591	my ($pid, $cb) = @{$_[0]};	1652	my ($pid, $cb) = @{$_[0]};
1592		1653
1593	delete $PID_CB{$pid}{$cb};	1654	delete $PID_CB{$pid}{$cb};
1594	delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} };	1655	delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} };
1595		1656
1596	undef $CHLD_W unless keys %PID_CB;	1657	undef $CHLD_W unless keys %PID_CB;
		1658	};
		1659	};
		1660	die if $@;
		1661
		1662	&child
1597	}	1663	}
1598		1664
1599	# idle emulation is done by simply using a timer, regardless	1665	# idle emulation is done by simply using a timer, regardless
1600	# of whether the process is idle or not, and not letting	1666	# of whether the process is idle or not, and not letting
1601	# the callback use more than 50% of the time.	1667	# the callback use more than 50% of the time.
1602	sub idle {	1668	sub idle {
		1669	eval q{ # poor man's autoloading {}
		1670	*idle = sub {
1603	my (undef, %arg) = @_;	1671	my (undef, %arg) = @_;
1604		1672
1605	my ($cb, $w, $rcb) = $arg{cb};	1673	my ($cb, $w, $rcb) = $arg{cb};
1606		1674
1607	$rcb = sub {	1675	$rcb = sub {
1608	if ($cb) {	1676	if ($cb) {
1609	$w = _time;	1677	$w = _time;
1610	&$cb;	1678	&$cb;
1611	$w = _time - $w;	1679	$w = _time - $w;
1612		1680
1613	# never use more then 50% of the time for the idle watcher,	1681	# never use more then 50% of the time for the idle watcher,
1614	# within some limits	1682	# within some limits
1615	$w = 0.0001 if $w < 0.0001;	1683	$w = 0.0001 if $w < 0.0001;
1616	$w = 5 if $w > 5;	1684	$w = 5 if $w > 5;
1617		1685
1618	$w = AE::timer $w, 0, $rcb;	1686	$w = AE::timer $w, 0, $rcb;
1619	} else {	1687	} else {
1620	# clean up...	1688	# clean up...
1621	undef $w;	1689	undef $w;
1622	undef $rcb;	1690	undef $rcb;
		1691	}
		1692	};
		1693
		1694	$w = AE::timer 0.05, 0, $rcb;
		1695
		1696	bless \\$cb, "AnyEvent::Base::idle"
1623	}	1697	};
		1698
		1699	*AnyEvent::Base::idle::DESTROY = sub {
		1700	undef $${$_[0]};
		1701	};
1624	};	1702	};
		1703	die if $@;
1625		1704
1626	$w = AE::timer 0.05, 0, $rcb;	1705	&idle
1627
1628	bless \\$cb, "AnyEvent::Base::idle"
1629	}
1630
1631	sub AnyEvent::Base::idle::DESTROY {
1632	undef $${$_[0]};
1633	}	1706	}
1634		1707
1635	package AnyEvent::CondVar;	1708	package AnyEvent::CondVar;
1636		1709
1637	our @ISA = AnyEvent::CondVar::Base::;	1710	our @ISA = AnyEvent::CondVar::Base::;
…		…
1911	warn "read: $input\n"; # output what has been read	1984	warn "read: $input\n"; # output what has been read
1912	$cv->send if $input =~ /^q/i; # quit program if /^q/i	1985	$cv->send if $input =~ /^q/i; # quit program if /^q/i
1913	},	1986	},
1914	);	1987	);
1915		1988
1916	my $time_watcher; # can only be used once
1917
1918	sub new_timer {
1919	$timer = AnyEvent->timer (after => 1, cb => sub {	1989	my $time_watcher = AnyEvent->timer (after => 1, interval => 1, cb => sub {
1920	warn "timeout\n"; # print 'timeout' about every second	1990	warn "timeout\n"; # print 'timeout' at most every second
1921	&new_timer; # and restart the time
1922	});	1991	});
1923	}
1924
1925	new_timer; # create first timer
1926		1992
1927	$cv->recv; # wait until user enters /^q/i	1993	$cv->recv; # wait until user enters /^q/i
1928		1994
1929	=head1 REAL-WORLD EXAMPLE	1995	=head1 REAL-WORLD EXAMPLE
1930		1996
…		…
2003		2069
2004	The actual code goes further and collects all errors (C<die>s, exceptions)	2070	The actual code goes further and collects all errors (C<die>s, exceptions)
2005	that occurred during request processing. The C<result> method detects	2071	that occurred during request processing. The C<result> method detects
2006	whether an exception as thrown (it is stored inside the $txn object)	2072	whether an exception as thrown (it is stored inside the $txn object)
2007	and just throws the exception, which means connection errors and other	2073	and just throws the exception, which means connection errors and other
2008	problems get reported tot he code that tries to use the result, not in a	2074	problems get reported to the code that tries to use the result, not in a
2009	random callback.	2075	random callback.
2010		2076
2011	All of this enables the following usage styles:	2077	All of this enables the following usage styles:
2012		2078
2013	1. Blocking:	2079	1. Blocking:
…		…
2374	As you can see, the AnyEvent + EV combination even beats the	2440	As you can see, the AnyEvent + EV combination even beats the
2375	hand-optimised "raw sockets benchmark", while AnyEvent + its pure perl	2441	hand-optimised "raw sockets benchmark", while AnyEvent + its pure perl
2376	backend easily beats IO::Lambda and POE.	2442	backend easily beats IO::Lambda and POE.
2377		2443
2378	And even the 100% non-blocking version written using the high-level (and	2444	And even the 100% non-blocking version written using the high-level (and
2379	slow :) L<AnyEvent::Handle> abstraction beats both POE and IO::Lambda by a	2445	slow :) L<AnyEvent::Handle> abstraction beats both POE and IO::Lambda
2380	large margin, even though it does all of DNS, tcp-connect and socket I/O	2446	higher level ("unoptimised") abstractions by a large margin, even though
2381	in a non-blocking way.	2447	it does all of DNS, tcp-connect and socket I/O in a non-blocking way.
2382		2448
2383	The two AnyEvent benchmarks programs can be found as F<eg/ae0.pl> and	2449	The two AnyEvent benchmarks programs can be found as F<eg/ae0.pl> and
2384	F<eg/ae2.pl> in the AnyEvent distribution, the remaining benchmarks are	2450	F<eg/ae2.pl> in the AnyEvent distribution, the remaining benchmarks are
2385	part of the IO::lambda distribution and were used without any changes.	2451	part of the IO::Lambda distribution and were used without any changes.
2386		2452
2387		2453
2388	=head1 SIGNALS	2454	=head1 SIGNALS
2389		2455
2390	AnyEvent currently installs handlers for these signals:	2456	AnyEvent currently installs handlers for these signals:
…		…
2432	it's built-in modules) are required to use it.	2498	it's built-in modules) are required to use it.
2433		2499
2434	That does not mean that AnyEvent won't take advantage of some additional	2500	That does not mean that AnyEvent won't take advantage of some additional
2435	modules if they are installed.	2501	modules if they are installed.
2436		2502
2437	This section epxlains which additional modules will be used, and how they	2503	This section explains which additional modules will be used, and how they
2438	affect AnyEvent's operetion.	2504	affect AnyEvent's operation.
2439		2505
2440	=over 4	2506	=over 4
2441		2507
2442	=item L<Async::Interrupt>	2508	=item L<Async::Interrupt>
2443		2509
…		…
2448	catch the signals) with some delay (default is 10 seconds, look for	2514	catch the signals) with some delay (default is 10 seconds, look for
2449	C<$AnyEvent::MAX_SIGNAL_LATENCY>).	2515	C<$AnyEvent::MAX_SIGNAL_LATENCY>).
2450		2516
2451	If this module is available, then it will be used to implement signal	2517	If this module is available, then it will be used to implement signal
2452	catching, which means that signals will not be delayed, and the event loop	2518	catching, which means that signals will not be delayed, and the event loop
2453	will not be interrupted regularly, which is more efficient (And good for	2519	will not be interrupted regularly, which is more efficient (and good for
2454	battery life on laptops).	2520	battery life on laptops).
2455		2521
2456	This affects not just the pure-perl event loop, but also other event loops	2522	This affects not just the pure-perl event loop, but also other event loops
2457	that have no signal handling on their own (e.g. Glib, Tk, Qt).	2523	that have no signal handling on their own (e.g. Glib, Tk, Qt).
2458		2524
…		…
2470	automatic timer adjustments even when no monotonic clock is available,	2536	automatic timer adjustments even when no monotonic clock is available,
2471	can take avdantage of advanced kernel interfaces such as C<epoll> and	2537	can take avdantage of advanced kernel interfaces such as C<epoll> and
2472	C<kqueue>, and is the fastest backend I<by far>. You can even embed	2538	C<kqueue>, and is the fastest backend I<by far>. You can even embed
2473	L<Glib>/L<Gtk2> in it (or vice versa, see L<EV::Glib> and L<Glib::EV>).	2539	L<Glib>/L<Gtk2> in it (or vice versa, see L<EV::Glib> and L<Glib::EV>).
2474		2540
		2541	If you only use backends that rely on another event loop (e.g. C<Tk>),
		2542	then this module will do nothing for you.
		2543
2475	=item L<Guard>	2544	=item L<Guard>
2476		2545
2477	The guard module, when used, will be used to implement	2546	The guard module, when used, will be used to implement
2478	C<AnyEvent::Util::guard>. This speeds up guards considerably (and uses a	2547	C<AnyEvent::Util::guard>. This speeds up guards considerably (and uses a
2479	lot less memory), but otherwise doesn't affect guard operation much. It is	2548	lot less memory), but otherwise doesn't affect guard operation much. It is
2480	purely used for performance.	2549	purely used for performance.
2481		2550
2482	=item L<JSON> and L<JSON::XS>	2551	=item L<JSON> and L<JSON::XS>
2483		2552
2484	This module is required when you want to read or write JSON data via	2553	One of these modules is required when you want to read or write JSON data
2485	L<AnyEvent::Handle>. It is also written in pure-perl, but can take	2554	via L<AnyEvent::Handle>. L<JSON> is also written in pure-perl, but can take
2486	advantage of the ultra-high-speed L<JSON::XS> module when it is installed.	2555	advantage of the ultra-high-speed L<JSON::XS> module when it is installed.
2487
2488	In fact, L<AnyEvent::Handle> will use L<JSON::XS> by default if it is
2489	installed.
2490		2556
2491	=item L<Net::SSLeay>	2557	=item L<Net::SSLeay>
2492		2558
2493	Implementing TLS/SSL in Perl is certainly interesting, but not very	2559	Implementing TLS/SSL in Perl is certainly interesting, but not very
2494	worthwhile: If this module is installed, then L<AnyEvent::Handle> (with	2560	worthwhile: If this module is installed, then L<AnyEvent::Handle> (with
…		…
2505		2571
2506		2572
2507	=head1 FORK	2573	=head1 FORK
2508		2574
2509	Most event libraries are not fork-safe. The ones who are usually are	2575	Most event libraries are not fork-safe. The ones who are usually are
2510	because they rely on inefficient but fork-safe C<select> or C<poll>	2576	because they rely on inefficient but fork-safe C<select> or C<poll> calls
2511	calls. Only L<EV> is fully fork-aware.	2577	- higher performance APIs such as BSD's kqueue or the dreaded Linux epoll
		2578	are usually badly thought-out hacks that are incompatible with fork in
		2579	one way or another. Only L<EV> is fully fork-aware and ensures that you
		2580	continue event-processing in both parent and child (or both, if you know
		2581	what you are doing).
		2582
		2583	This means that, in general, you cannot fork and do event processing in
		2584	the child if the event library was initialised before the fork (which
		2585	usually happens when the first AnyEvent watcher is created, or the library
		2586	is loaded).
2512		2587
2513	If you have to fork, you must either do so I<before> creating your first	2588	If you have to fork, you must either do so I<before> creating your first
2514	watcher OR you must not use AnyEvent at all in the child OR you must do	2589	watcher OR you must not use AnyEvent at all in the child OR you must do
2515	something completely out of the scope of AnyEvent.	2590	something completely out of the scope of AnyEvent.
		2591
		2592	The problem of doing event processing in the parent I<and> the child
		2593	is much more complicated: even for backends that I<are> fork-aware or
		2594	fork-safe, their behaviour is not usually what you want: fork clones all
		2595	watchers, that means all timers, I/O watchers etc. are active in both
		2596	parent and child, which is almost never what you want. USing C<exec>
		2597	to start worker children from some kind of manage rprocess is usually
		2598	preferred, because it is much easier and cleaner, at the expense of having
		2599	to have another binary.
2516		2600
2517		2601
2518	=head1 SECURITY CONSIDERATIONS	2602	=head1 SECURITY CONSIDERATIONS
2519		2603
2520	AnyEvent can be forced to load any event model via	2604	AnyEvent can be forced to load any event model via

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Comparing AnyEvent/lib/AnyEvent.pm (file contents): Revision 1.279 by root, Sun Aug 9 16:05:11 2009 UTC vs. Revision 1.323 by root, Thu May 20 21:22:20 2010 UTC

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Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.279 by root, Sun Aug 9 16:05:11 2009 UTC vs.
Revision 1.323 by root, Thu May 20 21:22:20 2010 UTC