ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/AnyEvent/lib/AnyEvent.pm
(Generate patch)

Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.134 by root, Sun May 25 04:44:04 2008 UTC vs.
Revision 1.175 by root, Sun Jul 27 08:43:32 2008 UTC

1=head1 => NAME 1=head1 NAME
2 2
3AnyEvent - provide framework for multiple event loops 3AnyEvent - provide framework for multiple event loops
4 4
5EV, Event, Glib, Tk, Perl, Event::Lib, Qt, POE - various supported event loops 5EV, Event, Glib, Tk, Perl, Event::Lib, Qt, POE - various supported event loops
6 6
7=head1 SYNOPSIS 7=head1 SYNOPSIS
8 8
9 use AnyEvent; 9 use AnyEvent;
10 10
11 my $w = AnyEvent->io (fh => $fh, poll => "r|w", cb => sub { 11 my $w = AnyEvent->io (fh => $fh, poll => "r|w", cb => sub { ... });
12 ...
13 });
14 12
15 my $w = AnyEvent->timer (after => $seconds, cb => sub { 13 my $w = AnyEvent->timer (after => $seconds, cb => sub { ... });
14 my $w = AnyEvent->timer (after => $seconds, interval => $seconds, cb => ...
15
16 print AnyEvent->now; # prints current event loop time
17 print AnyEvent->time; # think Time::HiRes::time or simply CORE::time.
18
19 my $w = AnyEvent->signal (signal => "TERM", cb => sub { ... });
20
21 my $w = AnyEvent->child (pid => $pid, cb => sub {
22 my ($pid, $status) = @_;
16 ... 23 ...
17 }); 24 });
18 25
19 my $w = AnyEvent->condvar; # stores whether a condition was flagged 26 my $w = AnyEvent->condvar; # stores whether a condition was flagged
20 $w->send; # wake up current and all future recv's 27 $w->send; # wake up current and all future recv's
21 $w->recv; # enters "main loop" till $condvar gets ->send 28 $w->recv; # enters "main loop" till $condvar gets ->send
29 # use a condvar in callback mode:
30 $w->cb (sub { $_[0]->recv });
31
32=head1 INTRODUCTION/TUTORIAL
33
34This manpage is mainly a reference manual. If you are interested
35in a tutorial or some gentle introduction, have a look at the
36L<AnyEvent::Intro> manpage.
22 37
23=head1 WHY YOU SHOULD USE THIS MODULE (OR NOT) 38=head1 WHY YOU SHOULD USE THIS MODULE (OR NOT)
24 39
25Glib, POE, IO::Async, Event... CPAN offers event models by the dozen 40Glib, POE, IO::Async, Event... CPAN offers event models by the dozen
26nowadays. So what is different about AnyEvent? 41nowadays. So what is different about AnyEvent?
27 42
28Executive Summary: AnyEvent is I<compatible>, AnyEvent is I<free of 43Executive Summary: AnyEvent is I<compatible>, AnyEvent is I<free of
29policy> and AnyEvent is I<small and efficient>. 44policy> and AnyEvent is I<small and efficient>.
30 45
31First and foremost, I<AnyEvent is not an event model> itself, it only 46First and foremost, I<AnyEvent is not an event model> itself, it only
32interfaces to whatever event model the main program happens to use in a 47interfaces to whatever event model the main program happens to use, in a
33pragmatic way. For event models and certain classes of immortals alike, 48pragmatic way. For event models and certain classes of immortals alike,
34the statement "there can only be one" is a bitter reality: In general, 49the statement "there can only be one" is a bitter reality: In general,
35only one event loop can be active at the same time in a process. AnyEvent 50only one event loop can be active at the same time in a process. AnyEvent
36helps hiding the differences between those event loops. 51cannot change this, but it can hide the differences between those event
52loops.
37 53
38The goal of AnyEvent is to offer module authors the ability to do event 54The goal of AnyEvent is to offer module authors the ability to do event
39programming (waiting for I/O or timer events) without subscribing to a 55programming (waiting for I/O or timer events) without subscribing to a
40religion, a way of living, and most importantly: without forcing your 56religion, a way of living, and most importantly: without forcing your
41module users into the same thing by forcing them to use the same event 57module users into the same thing by forcing them to use the same event
42model you use. 58model you use.
43 59
44For modules like POE or IO::Async (which is a total misnomer as it is 60For modules like POE or IO::Async (which is a total misnomer as it is
45actually doing all I/O I<synchronously>...), using them in your module is 61actually doing all I/O I<synchronously>...), using them in your module is
46like joining a cult: After you joined, you are dependent on them and you 62like joining a cult: After you joined, you are dependent on them and you
47cannot use anything else, as it is simply incompatible to everything that 63cannot use anything else, as they are simply incompatible to everything
48isn't itself. What's worse, all the potential users of your module are 64that isn't them. What's worse, all the potential users of your
49I<also> forced to use the same event loop you use. 65module are I<also> forced to use the same event loop you use.
50 66
51AnyEvent is different: AnyEvent + POE works fine. AnyEvent + Glib works 67AnyEvent is different: AnyEvent + POE works fine. AnyEvent + Glib works
52fine. AnyEvent + Tk works fine etc. etc. but none of these work together 68fine. AnyEvent + Tk works fine etc. etc. but none of these work together
53with the rest: POE + IO::Async? no go. Tk + Event? no go. Again: if 69with the rest: POE + IO::Async? No go. Tk + Event? No go. Again: if
54your module uses one of those, every user of your module has to use it, 70your module uses one of those, every user of your module has to use it,
55too. But if your module uses AnyEvent, it works transparently with all 71too. But if your module uses AnyEvent, it works transparently with all
56event models it supports (including stuff like POE and IO::Async, as long 72event models it supports (including stuff like IO::Async, as long as those
57as those use one of the supported event loops. It is trivial to add new 73use one of the supported event loops. It is trivial to add new event loops
58event loops to AnyEvent, too, so it is future-proof). 74to AnyEvent, too, so it is future-proof).
59 75
60In addition to being free of having to use I<the one and only true event 76In addition to being free of having to use I<the one and only true event
61model>, AnyEvent also is free of bloat and policy: with POE or similar 77model>, AnyEvent also is free of bloat and policy: with POE or similar
62modules, you get an enormous amount of code and strict rules you have to 78modules, you get an enormous amount of code and strict rules you have to
63follow. AnyEvent, on the other hand, is lean and up to the point, by only 79follow. AnyEvent, on the other hand, is lean and up to the point, by only
64offering the functionality that is necessary, in as thin as a wrapper as 80offering the functionality that is necessary, in as thin as a wrapper as
65technically possible. 81technically possible.
66 82
83Of course, AnyEvent comes with a big (and fully optional!) toolbox
84of useful functionality, such as an asynchronous DNS resolver, 100%
85non-blocking connects (even with TLS/SSL, IPv6 and on broken platforms
86such as Windows) and lots of real-world knowledge and workarounds for
87platform bugs and differences.
88
67Of course, if you want lots of policy (this can arguably be somewhat 89Now, if you I<do want> lots of policy (this can arguably be somewhat
68useful) and you want to force your users to use the one and only event 90useful) and you want to force your users to use the one and only event
69model, you should I<not> use this module. 91model, you should I<not> use this module.
70 92
71=head1 DESCRIPTION 93=head1 DESCRIPTION
72 94
102starts using it, all bets are off. Maybe you should tell their authors to 124starts using it, all bets are off. Maybe you should tell their authors to
103use AnyEvent so their modules work together with others seamlessly... 125use AnyEvent so their modules work together with others seamlessly...
104 126
105The pure-perl implementation of AnyEvent is called 127The pure-perl implementation of AnyEvent is called
106C<AnyEvent::Impl::Perl>. Like other event modules you can load it 128C<AnyEvent::Impl::Perl>. Like other event modules you can load it
107explicitly. 129explicitly and enjoy the high availability of that event loop :)
108 130
109=head1 WATCHERS 131=head1 WATCHERS
110 132
111AnyEvent has the central concept of a I<watcher>, which is an object that 133AnyEvent has the central concept of a I<watcher>, which is an object that
112stores relevant data for each kind of event you are waiting for, such as 134stores relevant data for each kind of event you are waiting for, such as
126Many watchers either are used with "recursion" (repeating timers for 148Many watchers either are used with "recursion" (repeating timers for
127example), or need to refer to their watcher object in other ways. 149example), or need to refer to their watcher object in other ways.
128 150
129An any way to achieve that is this pattern: 151An any way to achieve that is this pattern:
130 152
131 my $w; $w = AnyEvent->type (arg => value ..., cb => sub { 153 my $w; $w = AnyEvent->type (arg => value ..., cb => sub {
132 # you can use $w here, for example to undef it 154 # you can use $w here, for example to undef it
133 undef $w; 155 undef $w;
134 }); 156 });
135 157
136Note that C<my $w; $w => combination. This is necessary because in Perl, 158Note that C<my $w; $w => combination. This is necessary because in Perl,
137my variables are only visible after the statement in which they are 159my variables are only visible after the statement in which they are
138declared. 160declared.
139 161
140=head2 I/O WATCHERS 162=head2 I/O WATCHERS
141 163
142You can create an I/O watcher by calling the C<< AnyEvent->io >> method 164You can create an I/O watcher by calling the C<< AnyEvent->io >> method
143with the following mandatory key-value pairs as arguments: 165with the following mandatory key-value pairs as arguments:
144 166
145C<fh> the Perl I<file handle> (I<not> file descriptor) to watch 167C<fh> the Perl I<file handle> (I<not> file descriptor) to watch for events
146for events. C<poll> must be a string that is either C<r> or C<w>, 168(AnyEvent might or might not keep a reference to this file handle). C<poll>
147which creates a watcher waiting for "r"eadable or "w"ritable events, 169must be a string that is either C<r> or C<w>, which creates a watcher
148respectively. C<cb> is the callback to invoke each time the file handle 170waiting for "r"eadable or "w"ritable events, respectively. C<cb> is the
149becomes ready. 171callback to invoke each time the file handle becomes ready.
150 172
151Although the callback might get passed parameters, their value and 173Although the callback might get passed parameters, their value and
152presence is undefined and you cannot rely on them. Portable AnyEvent 174presence is undefined and you cannot rely on them. Portable AnyEvent
153callbacks cannot use arguments passed to I/O watcher callbacks. 175callbacks cannot use arguments passed to I/O watcher callbacks.
154 176
158 180
159Some event loops issue spurious readyness notifications, so you should 181Some event loops issue spurious readyness notifications, so you should
160always use non-blocking calls when reading/writing from/to your file 182always use non-blocking calls when reading/writing from/to your file
161handles. 183handles.
162 184
163Example:
164
165 # wait for readability of STDIN, then read a line and disable the watcher 185Example: wait for readability of STDIN, then read a line and disable the
186watcher.
187
166 my $w; $w = AnyEvent->io (fh => \*STDIN, poll => 'r', cb => sub { 188 my $w; $w = AnyEvent->io (fh => \*STDIN, poll => 'r', cb => sub {
167 chomp (my $input = <STDIN>); 189 chomp (my $input = <STDIN>);
168 warn "read: $input\n"; 190 warn "read: $input\n";
169 undef $w; 191 undef $w;
170 }); 192 });
180 202
181Although the callback might get passed parameters, their value and 203Although the callback might get passed parameters, their value and
182presence is undefined and you cannot rely on them. Portable AnyEvent 204presence is undefined and you cannot rely on them. Portable AnyEvent
183callbacks cannot use arguments passed to time watcher callbacks. 205callbacks cannot use arguments passed to time watcher callbacks.
184 206
185The timer callback will be invoked at most once: if you want a repeating 207The callback will normally be invoked once only. If you specify another
186timer you have to create a new watcher (this is a limitation by both Tk 208parameter, C<interval>, as a strictly positive number (> 0), then the
187and Glib). 209callback will be invoked regularly at that interval (in fractional
210seconds) after the first invocation. If C<interval> is specified with a
211false value, then it is treated as if it were missing.
188 212
189Example: 213The callback will be rescheduled before invoking the callback, but no
214attempt is done to avoid timer drift in most backends, so the interval is
215only approximate.
190 216
191 # fire an event after 7.7 seconds 217Example: fire an event after 7.7 seconds.
218
192 my $w = AnyEvent->timer (after => 7.7, cb => sub { 219 my $w = AnyEvent->timer (after => 7.7, cb => sub {
193 warn "timeout\n"; 220 warn "timeout\n";
194 }); 221 });
195 222
196 # to cancel the timer: 223 # to cancel the timer:
197 undef $w; 224 undef $w;
198 225
199Example 2:
200
201 # fire an event after 0.5 seconds, then roughly every second 226Example 2: fire an event after 0.5 seconds, then roughly every second.
202 my $w;
203 227
204 my $cb = sub {
205 # cancel the old timer while creating a new one
206 $w = AnyEvent->timer (after => 1, cb => $cb); 228 my $w = AnyEvent->timer (after => 0.5, interval => 1, cb => sub {
229 warn "timeout\n";
207 }; 230 };
208
209 # start the "loop" by creating the first watcher
210 $w = AnyEvent->timer (after => 0.5, cb => $cb);
211 231
212=head3 TIMING ISSUES 232=head3 TIMING ISSUES
213 233
214There are two ways to handle timers: based on real time (relative, "fire 234There are two ways to handle timers: based on real time (relative, "fire
215in 10 seconds") and based on wallclock time (absolute, "fire at 12 235in 10 seconds") and based on wallclock time (absolute, "fire at 12
227timers. 247timers.
228 248
229AnyEvent always prefers relative timers, if available, matching the 249AnyEvent always prefers relative timers, if available, matching the
230AnyEvent API. 250AnyEvent API.
231 251
252AnyEvent has two additional methods that return the "current time":
253
254=over 4
255
256=item AnyEvent->time
257
258This returns the "current wallclock time" as a fractional number of
259seconds since the Epoch (the same thing as C<time> or C<Time::HiRes::time>
260return, and the result is guaranteed to be compatible with those).
261
262It progresses independently of any event loop processing, i.e. each call
263will check the system clock, which usually gets updated frequently.
264
265=item AnyEvent->now
266
267This also returns the "current wallclock time", but unlike C<time>, above,
268this value might change only once per event loop iteration, depending on
269the event loop (most return the same time as C<time>, above). This is the
270time that AnyEvent's timers get scheduled against.
271
272I<In almost all cases (in all cases if you don't care), this is the
273function to call when you want to know the current time.>
274
275This function is also often faster then C<< AnyEvent->time >>, and
276thus the preferred method if you want some timestamp (for example,
277L<AnyEvent::Handle> uses this to update it's activity timeouts).
278
279The rest of this section is only of relevance if you try to be very exact
280with your timing, you can skip it without bad conscience.
281
282For a practical example of when these times differ, consider L<Event::Lib>
283and L<EV> and the following set-up:
284
285The event loop is running and has just invoked one of your callback at
286time=500 (assume no other callbacks delay processing). In your callback,
287you wait a second by executing C<sleep 1> (blocking the process for a
288second) and then (at time=501) you create a relative timer that fires
289after three seconds.
290
291With L<Event::Lib>, C<< AnyEvent->time >> and C<< AnyEvent->now >> will
292both return C<501>, because that is the current time, and the timer will
293be scheduled to fire at time=504 (C<501> + C<3>).
294
295With L<EV>, C<< AnyEvent->time >> returns C<501> (as that is the current
296time), but C<< AnyEvent->now >> returns C<500>, as that is the time the
297last event processing phase started. With L<EV>, your timer gets scheduled
298to run at time=503 (C<500> + C<3>).
299
300In one sense, L<Event::Lib> is more exact, as it uses the current time
301regardless of any delays introduced by event processing. However, most
302callbacks do not expect large delays in processing, so this causes a
303higher drift (and a lot more system calls to get the current time).
304
305In another sense, L<EV> is more exact, as your timer will be scheduled at
306the same time, regardless of how long event processing actually took.
307
308In either case, if you care (and in most cases, you don't), then you
309can get whatever behaviour you want with any event loop, by taking the
310difference between C<< AnyEvent->time >> and C<< AnyEvent->now >> into
311account.
312
313=back
314
232=head2 SIGNAL WATCHERS 315=head2 SIGNAL WATCHERS
233 316
234You can watch for signals using a signal watcher, C<signal> is the signal 317You can watch for signals using a signal watcher, C<signal> is the signal
235I<name> without any C<SIG> prefix, C<cb> is the Perl callback to 318I<name> in uppercase and without any C<SIG> prefix, C<cb> is the Perl
236be invoked whenever a signal occurs. 319callback to be invoked whenever a signal occurs.
237 320
238Although the callback might get passed parameters, their value and 321Although the callback might get passed parameters, their value and
239presence is undefined and you cannot rely on them. Portable AnyEvent 322presence is undefined and you cannot rely on them. Portable AnyEvent
240callbacks cannot use arguments passed to signal watcher callbacks. 323callbacks cannot use arguments passed to signal watcher callbacks.
241 324
277AnyEvent program, you I<have> to create at least one watcher before you 360AnyEvent program, you I<have> to create at least one watcher before you
278C<fork> the child (alternatively, you can call C<AnyEvent::detect>). 361C<fork> the child (alternatively, you can call C<AnyEvent::detect>).
279 362
280Example: fork a process and wait for it 363Example: fork a process and wait for it
281 364
282 my $done = AnyEvent->condvar; 365 my $done = AnyEvent->condvar;
283 366
284 my $pid = fork or exit 5; 367 my $pid = fork or exit 5;
285 368
286 my $w = AnyEvent->child ( 369 my $w = AnyEvent->child (
287 pid => $pid, 370 pid => $pid,
288 cb => sub { 371 cb => sub {
289 my ($pid, $status) = @_; 372 my ($pid, $status) = @_;
290 warn "pid $pid exited with status $status"; 373 warn "pid $pid exited with status $status";
291 $done->send; 374 $done->send;
292 }, 375 },
293 ); 376 );
294 377
295 # do something else, then wait for process exit 378 # do something else, then wait for process exit
296 $done->recv; 379 $done->recv;
297 380
298=head2 CONDITION VARIABLES 381=head2 CONDITION VARIABLES
299 382
300If you are familiar with some event loops you will know that all of them 383If you are familiar with some event loops you will know that all of them
301require you to run some blocking "loop", "run" or similar function that 384require you to run some blocking "loop", "run" or similar function that
307The instrument to do that is called a "condition variable", so called 390The instrument to do that is called a "condition variable", so called
308because they represent a condition that must become true. 391because they represent a condition that must become true.
309 392
310Condition variables can be created by calling the C<< AnyEvent->condvar 393Condition variables can be created by calling the C<< AnyEvent->condvar
311>> method, usually without arguments. The only argument pair allowed is 394>> method, usually without arguments. The only argument pair allowed is
395
312C<cb>, which specifies a callback to be called when the condition variable 396C<cb>, which specifies a callback to be called when the condition variable
313becomes true. 397becomes true, with the condition variable as the first argument (but not
398the results).
314 399
315After creation, the condition variable is "false" until it becomes "true" 400After creation, the condition variable is "false" until it becomes "true"
316by calling the C<send> method (or calling the condition variable as if it 401by calling the C<send> method (or calling the condition variable as if it
317were a callback). 402were a callback, read about the caveats in the description for the C<<
403->send >> method).
318 404
319Condition variables are similar to callbacks, except that you can 405Condition variables are similar to callbacks, except that you can
320optionally wait for them. They can also be called merge points - points 406optionally wait for them. They can also be called merge points - points
321in time where multiple outstanding events have been processed. And yet 407in time where multiple outstanding events have been processed. And yet
322another way to call them is transactions - each condition variable can be 408another way to call them is transactions - each condition variable can be
373 459
374 my $done = AnyEvent->condvar; 460 my $done = AnyEvent->condvar;
375 my $delay = AnyEvent->timer (after => 5, cb => $done); 461 my $delay = AnyEvent->timer (after => 5, cb => $done);
376 $done->recv; 462 $done->recv;
377 463
464Example: Imagine an API that returns a condvar and doesn't support
465callbacks. This is how you make a synchronous call, for example from
466the main program:
467
468 use AnyEvent::CouchDB;
469
470 ...
471
472 my @info = $couchdb->info->recv;
473
474And this is how you would just ste a callback to be called whenever the
475results are available:
476
477 $couchdb->info->cb (sub {
478 my @info = $_[0]->recv;
479 });
480
378=head3 METHODS FOR PRODUCERS 481=head3 METHODS FOR PRODUCERS
379 482
380These methods should only be used by the producing side, i.e. the 483These methods should only be used by the producing side, i.e. the
381code/module that eventually sends the signal. Note that it is also 484code/module that eventually sends the signal. Note that it is also
382the producer side which creates the condvar in most cases, but it isn't 485the producer side which creates the condvar in most cases, but it isn't
394immediately from within send. 497immediately from within send.
395 498
396Any arguments passed to the C<send> call will be returned by all 499Any arguments passed to the C<send> call will be returned by all
397future C<< ->recv >> calls. 500future C<< ->recv >> calls.
398 501
399Condition variables are overloaded so one can call them directly (as a 502Condition variables are overloaded so one can call them directly
400code reference). Calling them directly is the same as calling C<send>. 503(as a code reference). Calling them directly is the same as calling
504C<send>. Note, however, that many C-based event loops do not handle
505overloading, so as tempting as it may be, passing a condition variable
506instead of a callback does not work. Both the pure perl and EV loops
507support overloading, however, as well as all functions that use perl to
508invoke a callback (as in L<AnyEvent::Socket> and L<AnyEvent::DNS> for
509example).
401 510
402=item $cv->croak ($error) 511=item $cv->croak ($error)
403 512
404Similar to send, but causes all call's to C<< ->recv >> to invoke 513Similar to send, but causes all call's to C<< ->recv >> to invoke
405C<Carp::croak> with the given error message/object/scalar. 514C<Carp::croak> with the given error message/object/scalar.
509=item $bool = $cv->ready 618=item $bool = $cv->ready
510 619
511Returns true when the condition is "true", i.e. whether C<send> or 620Returns true when the condition is "true", i.e. whether C<send> or
512C<croak> have been called. 621C<croak> have been called.
513 622
514=item $cb = $cv->cb ([new callback]) 623=item $cb = $cv->cb ($cb->($cv))
515 624
516This is a mutator function that returns the callback set and optionally 625This is a mutator function that returns the callback set and optionally
517replaces it before doing so. 626replaces it before doing so.
518 627
519The callback will be called when the condition becomes "true", i.e. when 628The callback will be called when the condition becomes "true", i.e. when
520C<send> or C<croak> are called. Calling C<recv> inside the callback 629C<send> or C<croak> are called, with the only argument being the condition
521or at any later time is guaranteed not to block. 630variable itself. Calling C<recv> inside the callback or at any later time
631is guaranteed not to block.
522 632
523=back 633=back
524 634
525=head1 GLOBAL VARIABLES AND FUNCTIONS 635=head1 GLOBAL VARIABLES AND FUNCTIONS
526 636
655=item L<AnyEvent::Util> 765=item L<AnyEvent::Util>
656 766
657Contains various utility functions that replace often-used but blocking 767Contains various utility functions that replace often-used but blocking
658functions such as C<inet_aton> by event-/callback-based versions. 768functions such as C<inet_aton> by event-/callback-based versions.
659 769
660=item L<AnyEvent::Handle>
661
662Provide read and write buffers and manages watchers for reads and writes.
663
664=item L<AnyEvent::Socket> 770=item L<AnyEvent::Socket>
665 771
666Provides various utility functions for (internet protocol) sockets, 772Provides various utility functions for (internet protocol) sockets,
667addresses and name resolution. Also functions to create non-blocking tcp 773addresses and name resolution. Also functions to create non-blocking tcp
668connections or tcp servers, with IPv6 and SRV record support and more. 774connections or tcp servers, with IPv6 and SRV record support and more.
669 775
776=item L<AnyEvent::Handle>
777
778Provide read and write buffers, manages watchers for reads and writes,
779supports raw and formatted I/O, I/O queued and fully transparent and
780non-blocking SSL/TLS.
781
670=item L<AnyEvent::DNS> 782=item L<AnyEvent::DNS>
671 783
672Provides rich asynchronous DNS resolver capabilities. 784Provides rich asynchronous DNS resolver capabilities.
673 785
786=item L<AnyEvent::HTTP>
787
788A simple-to-use HTTP library that is capable of making a lot of concurrent
789HTTP requests.
790
674=item L<AnyEvent::HTTPD> 791=item L<AnyEvent::HTTPD>
675 792
676Provides a simple web application server framework. 793Provides a simple web application server framework.
677 794
678=item L<AnyEvent::FastPing> 795=item L<AnyEvent::FastPing>
679 796
680The fastest ping in the west. 797The fastest ping in the west.
798
799=item L<AnyEvent::DBI>
800
801Executes L<DBI> requests asynchronously in a proxy process.
802
803=item L<AnyEvent::AIO>
804
805Truly asynchronous I/O, should be in the toolbox of every event
806programmer. AnyEvent::AIO transparently fuses L<IO::AIO> and AnyEvent
807together.
808
809=item L<AnyEvent::BDB>
810
811Truly asynchronous Berkeley DB access. AnyEvent::BDB transparently fuses
812L<BDB> and AnyEvent together.
813
814=item L<AnyEvent::GPSD>
815
816A non-blocking interface to gpsd, a daemon delivering GPS information.
817
818=item L<AnyEvent::IGS>
819
820A non-blocking interface to the Internet Go Server protocol (used by
821L<App::IGS>).
681 822
682=item L<Net::IRC3> 823=item L<Net::IRC3>
683 824
684AnyEvent based IRC client module family. 825AnyEvent based IRC client module family.
685 826
698 839
699=item L<Coro> 840=item L<Coro>
700 841
701Has special support for AnyEvent via L<Coro::AnyEvent>. 842Has special support for AnyEvent via L<Coro::AnyEvent>.
702 843
703=item L<AnyEvent::AIO>, L<IO::AIO>
704
705Truly asynchronous I/O, should be in the toolbox of every event
706programmer. AnyEvent::AIO transparently fuses IO::AIO and AnyEvent
707together.
708
709=item L<AnyEvent::BDB>, L<BDB>
710
711Truly asynchronous Berkeley DB access. AnyEvent::AIO transparently fuses
712IO::AIO and AnyEvent together.
713
714=item L<IO::Lambda> 844=item L<IO::Lambda>
715 845
716The lambda approach to I/O - don't ask, look there. Can use AnyEvent. 846The lambda approach to I/O - don't ask, look there. Can use AnyEvent.
717 847
718=back 848=back
724no warnings; 854no warnings;
725use strict; 855use strict;
726 856
727use Carp; 857use Carp;
728 858
729our $VERSION = '4.03'; 859our $VERSION = 4.23;
730our $MODEL; 860our $MODEL;
731 861
732our $AUTOLOAD; 862our $AUTOLOAD;
733our @ISA; 863our @ISA;
734 864
865our @REGISTRY;
866
867our $WIN32;
868
869BEGIN {
870 my $win32 = ! ! ($^O =~ /mswin32/i);
871 eval "sub WIN32(){ $win32 }";
872}
873
735our $verbose = $ENV{PERL_ANYEVENT_VERBOSE}*1; 874our $verbose = $ENV{PERL_ANYEVENT_VERBOSE}*1;
736 875
737our @REGISTRY; 876our %PROTOCOL; # (ipv4|ipv6) => (1|2), higher numbers are preferred
738
739our %PROTOCOL; # (ipv4|ipv6) => (1|2)
740 877
741{ 878{
742 my $idx; 879 my $idx;
743 $PROTOCOL{$_} = ++$idx 880 $PROTOCOL{$_} = ++$idx
881 for reverse split /\s*,\s*/,
744 for split /\s*,\s*/, $ENV{PERL_ANYEVENT_PROTOCOLS} || "ipv4,ipv6"; 882 $ENV{PERL_ANYEVENT_PROTOCOLS} || "ipv4,ipv6";
745} 883}
746 884
747my @models = ( 885my @models = (
748 [EV:: => AnyEvent::Impl::EV::], 886 [EV:: => AnyEvent::Impl::EV::],
749 [Event:: => AnyEvent::Impl::Event::], 887 [Event:: => AnyEvent::Impl::Event::],
750 [Tk:: => AnyEvent::Impl::Tk::],
751 [Wx:: => AnyEvent::Impl::POE::],
752 [Prima:: => AnyEvent::Impl::POE::],
753 [AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl::], 888 [AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl::],
754 # everything below here will not be autoprobed as the pureperl backend should work everywhere 889 # everything below here will not be autoprobed
755 [Glib:: => AnyEvent::Impl::Glib::], 890 # as the pureperl backend should work everywhere
891 # and is usually faster
892 [Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles
893 [Glib:: => AnyEvent::Impl::Glib::], # becomes extremely slow with many watchers
756 [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy 894 [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy
757 [Qt:: => AnyEvent::Impl::Qt::], # requires special main program 895 [Qt:: => AnyEvent::Impl::Qt::], # requires special main program
758 [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza 896 [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza
897 [Wx:: => AnyEvent::Impl::POE::],
898 [Prima:: => AnyEvent::Impl::POE::],
759); 899);
760 900
761our %method = map +($_ => 1), qw(io timer signal child condvar one_event DESTROY); 901our %method = map +($_ => 1), qw(io timer time now signal child condvar one_event DESTROY);
762 902
763our @post_detect; 903our @post_detect;
764 904
765sub post_detect(&) { 905sub post_detect(&) {
766 my ($cb) = @_; 906 my ($cb) = @_;
783} 923}
784 924
785sub detect() { 925sub detect() {
786 unless ($MODEL) { 926 unless ($MODEL) {
787 no strict 'refs'; 927 no strict 'refs';
928 local $SIG{__DIE__};
788 929
789 if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) { 930 if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) {
790 my $model = "AnyEvent::Impl::$1"; 931 my $model = "AnyEvent::Impl::$1";
791 if (eval "require $model") { 932 if (eval "require $model") {
792 $MODEL = $model; 933 $MODEL = $model;
826 $MODEL 967 $MODEL
827 or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib."; 968 or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib.";
828 } 969 }
829 } 970 }
830 971
972 push @{"$MODEL\::ISA"}, "AnyEvent::Base";
973
831 unshift @ISA, $MODEL; 974 unshift @ISA, $MODEL;
832 push @{"$MODEL\::ISA"}, "AnyEvent::Base"; 975
976 require AnyEvent::Strict if $ENV{PERL_ANYEVENT_STRICT};
833 977
834 (shift @post_detect)->() while @post_detect; 978 (shift @post_detect)->() while @post_detect;
835 } 979 }
836 980
837 $MODEL 981 $MODEL
847 991
848 my $class = shift; 992 my $class = shift;
849 $class->$func (@_); 993 $class->$func (@_);
850} 994}
851 995
996# utility function to dup a filehandle. this is used by many backends
997# to support binding more than one watcher per filehandle (they usually
998# allow only one watcher per fd, so we dup it to get a different one).
999sub _dupfh($$$$) {
1000 my ($poll, $fh, $r, $w) = @_;
1001
1002 require Fcntl;
1003
1004 # cygwin requires the fh mode to be matching, unix doesn't
1005 my ($rw, $mode) = $poll eq "r" ? ($r, "<")
1006 : $poll eq "w" ? ($w, ">")
1007 : Carp::croak "AnyEvent->io requires poll set to either 'r' or 'w'";
1008
1009 open my $fh2, "$mode&" . fileno $fh
1010 or die "cannot dup() filehandle: $!";
1011
1012 # we assume CLOEXEC is already set by perl in all important cases
1013
1014 ($fh2, $rw)
1015}
1016
852package AnyEvent::Base; 1017package AnyEvent::Base;
1018
1019# default implementation for now and time
1020
1021use Time::HiRes ();
1022
1023sub time { Time::HiRes::time }
1024sub now { Time::HiRes::time }
853 1025
854# default implementation for ->condvar 1026# default implementation for ->condvar
855 1027
856sub condvar { 1028sub condvar {
857 bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, AnyEvent::CondVar:: 1029 bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, AnyEvent::CondVar::
878sub AnyEvent::Base::Signal::DESTROY { 1050sub AnyEvent::Base::Signal::DESTROY {
879 my ($signal, $cb) = @{$_[0]}; 1051 my ($signal, $cb) = @{$_[0]};
880 1052
881 delete $SIG_CB{$signal}{$cb}; 1053 delete $SIG_CB{$signal}{$cb};
882 1054
883 $SIG{$signal} = 'DEFAULT' unless keys %{ $SIG_CB{$signal} }; 1055 delete $SIG{$signal} unless keys %{ $SIG_CB{$signal} };
884} 1056}
885 1057
886# default implementation for ->child 1058# default implementation for ->child
887 1059
888our %PID_CB; 1060our %PID_CB;
915 or Carp::croak "required option 'pid' is missing"; 1087 or Carp::croak "required option 'pid' is missing";
916 1088
917 $PID_CB{$pid}{$arg{cb}} = $arg{cb}; 1089 $PID_CB{$pid}{$arg{cb}} = $arg{cb};
918 1090
919 unless ($WNOHANG) { 1091 unless ($WNOHANG) {
920 $WNOHANG = eval { require POSIX; &POSIX::WNOHANG } || 1; 1092 $WNOHANG = eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1;
921 } 1093 }
922 1094
923 unless ($CHLD_W) { 1095 unless ($CHLD_W) {
924 $CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld); 1096 $CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld);
925 # child could be a zombie already, so make at least one round 1097 # child could be a zombie already, so make at least one round
1058C<PERL_ANYEVENT_MODEL>. 1230C<PERL_ANYEVENT_MODEL>.
1059 1231
1060When set to C<2> or higher, cause AnyEvent to report to STDERR which event 1232When set to C<2> or higher, cause AnyEvent to report to STDERR which event
1061model it chooses. 1233model it chooses.
1062 1234
1235=item C<PERL_ANYEVENT_STRICT>
1236
1237AnyEvent does not do much argument checking by default, as thorough
1238argument checking is very costly. Setting this variable to a true value
1239will cause AnyEvent to load C<AnyEvent::Strict> and then to thoroughly
1240check the arguments passed to most method calls. If it finds any problems
1241it will croak.
1242
1243In other words, enables "strict" mode.
1244
1245Unlike C<use strict> it is definitely recommended ot keep it off in
1246production.
1247
1063=item C<PERL_ANYEVENT_MODEL> 1248=item C<PERL_ANYEVENT_MODEL>
1064 1249
1065This can be used to specify the event model to be used by AnyEvent, before 1250This can be used to specify the event model to be used by AnyEvent, before
1066auto detection and -probing kicks in. It must be a string consisting 1251auto detection and -probing kicks in. It must be a string consisting
1067entirely of ASCII letters. The string C<AnyEvent::Impl::> gets prepended 1252entirely of ASCII letters. The string C<AnyEvent::Impl::> gets prepended
1072This functionality might change in future versions. 1257This functionality might change in future versions.
1073 1258
1074For example, to force the pure perl model (L<AnyEvent::Impl::Perl>) you 1259For example, to force the pure perl model (L<AnyEvent::Impl::Perl>) you
1075could start your program like this: 1260could start your program like this:
1076 1261
1077 PERL_ANYEVENT_MODEL=Perl perl ... 1262 PERL_ANYEVENT_MODEL=Perl perl ...
1078 1263
1079=item C<PERL_ANYEVENT_PROTOCOLS> 1264=item C<PERL_ANYEVENT_PROTOCOLS>
1080 1265
1081Used by both L<AnyEvent::DNS> and L<AnyEvent::Socket> to determine preferences 1266Used by both L<AnyEvent::DNS> and L<AnyEvent::Socket> to determine preferences
1082for IPv4 or IPv6. The default is unspecified (and might change, or be the result 1267for IPv4 or IPv6. The default is unspecified (and might change, or be the result
1104some (broken) firewalls drop such DNS packets, which is why it is off by 1289some (broken) firewalls drop such DNS packets, which is why it is off by
1105default. 1290default.
1106 1291
1107Setting this variable to C<1> will cause L<AnyEvent::DNS> to announce 1292Setting this variable to C<1> will cause L<AnyEvent::DNS> to announce
1108EDNS0 in its DNS requests. 1293EDNS0 in its DNS requests.
1294
1295=item C<PERL_ANYEVENT_MAX_FORKS>
1296
1297The maximum number of child processes that C<AnyEvent::Util::fork_call>
1298will create in parallel.
1109 1299
1110=back 1300=back
1111 1301
1112=head1 EXAMPLE PROGRAM 1302=head1 EXAMPLE PROGRAM
1113 1303
1552specified in the variable. 1742specified in the variable.
1553 1743
1554You can make AnyEvent completely ignore this variable by deleting it 1744You can make AnyEvent completely ignore this variable by deleting it
1555before the first watcher gets created, e.g. with a C<BEGIN> block: 1745before the first watcher gets created, e.g. with a C<BEGIN> block:
1556 1746
1557 BEGIN { delete $ENV{PERL_ANYEVENT_MODEL} } 1747 BEGIN { delete $ENV{PERL_ANYEVENT_MODEL} }
1558 1748
1559 use AnyEvent; 1749 use AnyEvent;
1560 1750
1561Similar considerations apply to $ENV{PERL_ANYEVENT_VERBOSE}, as that can 1751Similar considerations apply to $ENV{PERL_ANYEVENT_VERBOSE}, as that can
1562be used to probe what backend is used and gain other information (which is 1752be used to probe what backend is used and gain other information (which is
1563probably even less useful to an attacker than PERL_ANYEVENT_MODEL). 1753probably even less useful to an attacker than PERL_ANYEVENT_MODEL), and
1754$ENV{PERL_ANYEGENT_STRICT}.
1755
1756
1757=head1 BUGS
1758
1759Perl 5.8 has numerous memleaks that sometimes hit this module and are hard
1760to work around. If you suffer from memleaks, first upgrade to Perl 5.10
1761and check wether the leaks still show up. (Perl 5.10.0 has other annoying
1762mamleaks, such as leaking on C<map> and C<grep> but it is usually not as
1763pronounced).
1564 1764
1565 1765
1566=head1 SEE ALSO 1766=head1 SEE ALSO
1567 1767
1568Utility functions: L<AnyEvent::Util>. 1768Utility functions: L<AnyEvent::Util>.
1585Nontrivial usage examples: L<Net::FCP>, L<Net::XMPP2>, L<AnyEvent::DNS>. 1785Nontrivial usage examples: L<Net::FCP>, L<Net::XMPP2>, L<AnyEvent::DNS>.
1586 1786
1587 1787
1588=head1 AUTHOR 1788=head1 AUTHOR
1589 1789
1590 Marc Lehmann <schmorp@schmorp.de> 1790 Marc Lehmann <schmorp@schmorp.de>
1591 http://home.schmorp.de/ 1791 http://home.schmorp.de/
1592 1792
1593=cut 1793=cut
1594 1794
15951 17951
1596 1796

Diff Legend

Removed lines
+ Added lines
< Changed lines
> Changed lines