… | |
… | |
5 | loops |
5 | loops |
6 | |
6 | |
7 | SYNOPSIS |
7 | SYNOPSIS |
8 | use AnyEvent; |
8 | use AnyEvent; |
9 | |
9 | |
10 | my $w = AnyEvent->io (fh => $fh, poll => "r|w", cb => sub { |
10 | my $w = AnyEvent->io (fh => $fh, poll => "r|w", cb => sub { ... }); |
11 | ... |
|
|
12 | }); |
|
|
13 | |
11 | |
14 | my $w = AnyEvent->timer (after => $seconds, cb => sub { |
12 | my $w = AnyEvent->timer (after => $seconds, cb => sub { ... }); |
|
|
13 | my $w = AnyEvent->timer (after => $seconds, interval => $seconds, cb => ... |
|
|
14 | |
|
|
15 | print AnyEvent->now; # prints current event loop time |
|
|
16 | print AnyEvent->time; # think Time::HiRes::time or simply CORE::time. |
|
|
17 | |
|
|
18 | my $w = AnyEvent->signal (signal => "TERM", cb => sub { ... }); |
|
|
19 | |
|
|
20 | my $w = AnyEvent->child (pid => $pid, cb => sub { |
|
|
21 | my ($pid, $status) = @_; |
15 | ... |
22 | ... |
16 | }); |
23 | }); |
17 | |
24 | |
18 | my $w = AnyEvent->condvar; # stores whether a condition was flagged |
25 | my $w = AnyEvent->condvar; # stores whether a condition was flagged |
19 | $w->send; # wake up current and all future recv's |
26 | $w->send; # wake up current and all future recv's |
20 | $w->recv; # enters "main loop" till $condvar gets ->send |
27 | $w->recv; # enters "main loop" till $condvar gets ->send |
|
|
28 | # use a condvar in callback mode: |
|
|
29 | $w->cb (sub { $_[0]->recv }); |
21 | |
30 | |
22 | INTRODUCTION/TUTORIAL |
31 | INTRODUCTION/TUTORIAL |
23 | This manpage is mainly a reference manual. If you are interested in a |
32 | This manpage is mainly a reference manual. If you are interested in a |
24 | tutorial or some gentle introduction, have a look at the AnyEvent::Intro |
33 | tutorial or some gentle introduction, have a look at the AnyEvent::Intro |
25 | manpage. |
34 | manpage. |
… | |
… | |
30 | |
39 | |
31 | Executive Summary: AnyEvent is *compatible*, AnyEvent is *free of |
40 | Executive Summary: AnyEvent is *compatible*, AnyEvent is *free of |
32 | policy* and AnyEvent is *small and efficient*. |
41 | policy* and AnyEvent is *small and efficient*. |
33 | |
42 | |
34 | First and foremost, *AnyEvent is not an event model* itself, it only |
43 | First and foremost, *AnyEvent is not an event model* itself, it only |
35 | interfaces to whatever event model the main program happens to use in a |
44 | interfaces to whatever event model the main program happens to use, in a |
36 | pragmatic way. For event models and certain classes of immortals alike, |
45 | pragmatic way. For event models and certain classes of immortals alike, |
37 | the statement "there can only be one" is a bitter reality: In general, |
46 | the statement "there can only be one" is a bitter reality: In general, |
38 | only one event loop can be active at the same time in a process. |
47 | only one event loop can be active at the same time in a process. |
39 | AnyEvent helps hiding the differences between those event loops. |
48 | AnyEvent cannot change this, but it can hide the differences between |
|
|
49 | those event loops. |
40 | |
50 | |
41 | The goal of AnyEvent is to offer module authors the ability to do event |
51 | The goal of AnyEvent is to offer module authors the ability to do event |
42 | programming (waiting for I/O or timer events) without subscribing to a |
52 | programming (waiting for I/O or timer events) without subscribing to a |
43 | religion, a way of living, and most importantly: without forcing your |
53 | religion, a way of living, and most importantly: without forcing your |
44 | module users into the same thing by forcing them to use the same event |
54 | module users into the same thing by forcing them to use the same event |
45 | model you use. |
55 | model you use. |
46 | |
56 | |
47 | For modules like POE or IO::Async (which is a total misnomer as it is |
57 | For modules like POE or IO::Async (which is a total misnomer as it is |
48 | actually doing all I/O *synchronously*...), using them in your module is |
58 | actually doing all I/O *synchronously*...), using them in your module is |
49 | like joining a cult: After you joined, you are dependent on them and you |
59 | like joining a cult: After you joined, you are dependent on them and you |
50 | cannot use anything else, as it is simply incompatible to everything |
60 | cannot use anything else, as they are simply incompatible to everything |
51 | that isn't itself. What's worse, all the potential users of your module |
61 | that isn't them. What's worse, all the potential users of your module |
52 | are *also* forced to use the same event loop you use. |
62 | are *also* forced to use the same event loop you use. |
53 | |
63 | |
54 | AnyEvent is different: AnyEvent + POE works fine. AnyEvent + Glib works |
64 | AnyEvent is different: AnyEvent + POE works fine. AnyEvent + Glib works |
55 | fine. AnyEvent + Tk works fine etc. etc. but none of these work together |
65 | fine. AnyEvent + Tk works fine etc. etc. but none of these work together |
56 | with the rest: POE + IO::Async? No go. Tk + Event? No go. Again: if your |
66 | with the rest: POE + IO::Async? No go. Tk + Event? No go. Again: if your |
57 | module uses one of those, every user of your module has to use it, too. |
67 | module uses one of those, every user of your module has to use it, too. |
58 | But if your module uses AnyEvent, it works transparently with all event |
68 | But if your module uses AnyEvent, it works transparently with all event |
59 | models it supports (including stuff like POE and IO::Async, as long as |
69 | models it supports (including stuff like IO::Async, as long as those use |
60 | those use one of the supported event loops. It is trivial to add new |
70 | one of the supported event loops. It is trivial to add new event loops |
61 | event loops to AnyEvent, too, so it is future-proof). |
71 | to AnyEvent, too, so it is future-proof). |
62 | |
72 | |
63 | In addition to being free of having to use *the one and only true event |
73 | In addition to being free of having to use *the one and only true event |
64 | model*, AnyEvent also is free of bloat and policy: with POE or similar |
74 | model*, AnyEvent also is free of bloat and policy: with POE or similar |
65 | modules, you get an enormous amount of code and strict rules you have to |
75 | modules, you get an enormous amount of code and strict rules you have to |
66 | follow. AnyEvent, on the other hand, is lean and up to the point, by |
76 | follow. AnyEvent, on the other hand, is lean and up to the point, by |
… | |
… | |
146 | |
156 | |
147 | I/O WATCHERS |
157 | I/O WATCHERS |
148 | You can create an I/O watcher by calling the "AnyEvent->io" method with |
158 | You can create an I/O watcher by calling the "AnyEvent->io" method with |
149 | the following mandatory key-value pairs as arguments: |
159 | the following mandatory key-value pairs as arguments: |
150 | |
160 | |
151 | "fh" the Perl *file handle* (*not* file descriptor) to watch for events. |
161 | "fh" the Perl *file handle* (*not* file descriptor) to watch for events |
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|
162 | (AnyEvent might or might not keep a reference to this file handle). |
152 | "poll" must be a string that is either "r" or "w", which creates a |
163 | "poll" must be a string that is either "r" or "w", which creates a |
153 | watcher waiting for "r"eadable or "w"ritable events, respectively. "cb" |
164 | watcher waiting for "r"eadable or "w"ritable events, respectively. "cb" |
154 | is the callback to invoke each time the file handle becomes ready. |
165 | is the callback to invoke each time the file handle becomes ready. |
155 | |
166 | |
156 | Although the callback might get passed parameters, their value and |
167 | Although the callback might get passed parameters, their value and |
… | |
… | |
163 | |
174 | |
164 | Some event loops issue spurious readyness notifications, so you should |
175 | Some event loops issue spurious readyness notifications, so you should |
165 | always use non-blocking calls when reading/writing from/to your file |
176 | always use non-blocking calls when reading/writing from/to your file |
166 | handles. |
177 | handles. |
167 | |
178 | |
168 | Example: |
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|
169 | |
|
|
170 | # wait for readability of STDIN, then read a line and disable the watcher |
179 | Example: wait for readability of STDIN, then read a line and disable the |
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|
180 | watcher. |
|
|
181 | |
171 | my $w; $w = AnyEvent->io (fh => \*STDIN, poll => 'r', cb => sub { |
182 | my $w; $w = AnyEvent->io (fh => \*STDIN, poll => 'r', cb => sub { |
172 | chomp (my $input = <STDIN>); |
183 | chomp (my $input = <STDIN>); |
173 | warn "read: $input\n"; |
184 | warn "read: $input\n"; |
174 | undef $w; |
185 | undef $w; |
175 | }); |
186 | }); |
… | |
… | |
184 | |
195 | |
185 | Although the callback might get passed parameters, their value and |
196 | Although the callback might get passed parameters, their value and |
186 | presence is undefined and you cannot rely on them. Portable AnyEvent |
197 | presence is undefined and you cannot rely on them. Portable AnyEvent |
187 | callbacks cannot use arguments passed to time watcher callbacks. |
198 | callbacks cannot use arguments passed to time watcher callbacks. |
188 | |
199 | |
189 | The timer callback will be invoked at most once: if you want a repeating |
200 | The callback will normally be invoked once only. If you specify another |
190 | timer you have to create a new watcher (this is a limitation by both Tk |
201 | parameter, "interval", as a strictly positive number (> 0), then the |
191 | and Glib). |
202 | callback will be invoked regularly at that interval (in fractional |
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|
203 | seconds) after the first invocation. If "interval" is specified with a |
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|
204 | false value, then it is treated as if it were missing. |
192 | |
205 | |
193 | Example: |
206 | The callback will be rescheduled before invoking the callback, but no |
|
|
207 | attempt is done to avoid timer drift in most backends, so the interval |
|
|
208 | is only approximate. |
194 | |
209 | |
195 | # fire an event after 7.7 seconds |
210 | Example: fire an event after 7.7 seconds. |
|
|
211 | |
196 | my $w = AnyEvent->timer (after => 7.7, cb => sub { |
212 | my $w = AnyEvent->timer (after => 7.7, cb => sub { |
197 | warn "timeout\n"; |
213 | warn "timeout\n"; |
198 | }); |
214 | }); |
199 | |
215 | |
200 | # to cancel the timer: |
216 | # to cancel the timer: |
201 | undef $w; |
217 | undef $w; |
202 | |
218 | |
203 | Example 2: |
|
|
204 | |
|
|
205 | # fire an event after 0.5 seconds, then roughly every second |
219 | Example 2: fire an event after 0.5 seconds, then roughly every second. |
206 | my $w; |
|
|
207 | |
220 | |
208 | my $cb = sub { |
|
|
209 | # cancel the old timer while creating a new one |
|
|
210 | $w = AnyEvent->timer (after => 1, cb => $cb); |
221 | my $w = AnyEvent->timer (after => 0.5, interval => 1, cb => sub { |
|
|
222 | warn "timeout\n"; |
211 | }; |
223 | }; |
212 | |
|
|
213 | # start the "loop" by creating the first watcher |
|
|
214 | $w = AnyEvent->timer (after => 0.5, cb => $cb); |
|
|
215 | |
224 | |
216 | TIMING ISSUES |
225 | TIMING ISSUES |
217 | There are two ways to handle timers: based on real time (relative, "fire |
226 | There are two ways to handle timers: based on real time (relative, "fire |
218 | in 10 seconds") and based on wallclock time (absolute, "fire at 12 |
227 | in 10 seconds") and based on wallclock time (absolute, "fire at 12 |
219 | o'clock"). |
228 | o'clock"). |
… | |
… | |
295 | the difference between "AnyEvent->time" and "AnyEvent->now" into |
304 | the difference between "AnyEvent->time" and "AnyEvent->now" into |
296 | account. |
305 | account. |
297 | |
306 | |
298 | SIGNAL WATCHERS |
307 | SIGNAL WATCHERS |
299 | You can watch for signals using a signal watcher, "signal" is the signal |
308 | You can watch for signals using a signal watcher, "signal" is the signal |
300 | *name* without any "SIG" prefix, "cb" is the Perl callback to be invoked |
309 | *name* in uppercase and without any "SIG" prefix, "cb" is the Perl |
301 | whenever a signal occurs. |
310 | callback to be invoked whenever a signal occurs. |
302 | |
311 | |
303 | Although the callback might get passed parameters, their value and |
312 | Although the callback might get passed parameters, their value and |
304 | presence is undefined and you cannot rely on them. Portable AnyEvent |
313 | presence is undefined and you cannot rely on them. Portable AnyEvent |
305 | callbacks cannot use arguments passed to signal watcher callbacks. |
314 | callbacks cannot use arguments passed to signal watcher callbacks. |
306 | |
315 | |
… | |
… | |
321 | |
330 | |
322 | CHILD PROCESS WATCHERS |
331 | CHILD PROCESS WATCHERS |
323 | You can also watch on a child process exit and catch its exit status. |
332 | You can also watch on a child process exit and catch its exit status. |
324 | |
333 | |
325 | The child process is specified by the "pid" argument (if set to 0, it |
334 | The child process is specified by the "pid" argument (if set to 0, it |
326 | watches for any child process exit). The watcher will trigger as often |
335 | watches for any child process exit). The watcher will triggered only |
327 | as status change for the child are received. This works by installing a |
336 | when the child process has finished and an exit status is available, not |
328 | signal handler for "SIGCHLD". The callback will be called with the pid |
337 | on any trace events (stopped/continued). |
329 | and exit status (as returned by waitpid), so unlike other watcher types, |
338 | |
330 | you *can* rely on child watcher callback arguments. |
339 | The callback will be called with the pid and exit status (as returned by |
|
|
340 | waitpid), so unlike other watcher types, you *can* rely on child watcher |
|
|
341 | callback arguments. |
|
|
342 | |
|
|
343 | This watcher type works by installing a signal handler for "SIGCHLD", |
|
|
344 | and since it cannot be shared, nothing else should use SIGCHLD or reap |
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|
345 | random child processes (waiting for specific child processes, e.g. |
|
|
346 | inside "system", is just fine). |
331 | |
347 | |
332 | There is a slight catch to child watchers, however: you usually start |
348 | There is a slight catch to child watchers, however: you usually start |
333 | them *after* the child process was created, and this means the process |
349 | them *after* the child process was created, and this means the process |
334 | could have exited already (and no SIGCHLD will be sent anymore). |
350 | could have exited already (and no SIGCHLD will be sent anymore). |
335 | |
351 | |
… | |
… | |
371 | The instrument to do that is called a "condition variable", so called |
387 | The instrument to do that is called a "condition variable", so called |
372 | because they represent a condition that must become true. |
388 | because they represent a condition that must become true. |
373 | |
389 | |
374 | Condition variables can be created by calling the "AnyEvent->condvar" |
390 | Condition variables can be created by calling the "AnyEvent->condvar" |
375 | method, usually without arguments. The only argument pair allowed is |
391 | method, usually without arguments. The only argument pair allowed is |
|
|
392 | |
376 | "cb", which specifies a callback to be called when the condition |
393 | "cb", which specifies a callback to be called when the condition |
377 | variable becomes true. |
394 | variable becomes true, with the condition variable as the first argument |
|
|
395 | (but not the results). |
378 | |
396 | |
379 | After creation, the condition variable is "false" until it becomes |
397 | After creation, the condition variable is "false" until it becomes |
380 | "true" by calling the "send" method (or calling the condition variable |
398 | "true" by calling the "send" method (or calling the condition variable |
381 | as if it were a callback, read about the caveats in the description for |
399 | as if it were a callback, read about the caveats in the description for |
382 | the "->send" method). |
400 | the "->send" method). |
… | |
… | |
438 | |
456 | |
439 | my $done = AnyEvent->condvar; |
457 | my $done = AnyEvent->condvar; |
440 | my $delay = AnyEvent->timer (after => 5, cb => $done); |
458 | my $delay = AnyEvent->timer (after => 5, cb => $done); |
441 | $done->recv; |
459 | $done->recv; |
442 | |
460 | |
|
|
461 | Example: Imagine an API that returns a condvar and doesn't support |
|
|
462 | callbacks. This is how you make a synchronous call, for example from the |
|
|
463 | main program: |
|
|
464 | |
|
|
465 | use AnyEvent::CouchDB; |
|
|
466 | |
|
|
467 | ... |
|
|
468 | |
|
|
469 | my @info = $couchdb->info->recv; |
|
|
470 | |
|
|
471 | And this is how you would just ste a callback to be called whenever the |
|
|
472 | results are available: |
|
|
473 | |
|
|
474 | $couchdb->info->cb (sub { |
|
|
475 | my @info = $_[0]->recv; |
|
|
476 | }); |
|
|
477 | |
443 | METHODS FOR PRODUCERS |
478 | METHODS FOR PRODUCERS |
444 | These methods should only be used by the producing side, i.e. the |
479 | These methods should only be used by the producing side, i.e. the |
445 | code/module that eventually sends the signal. Note that it is also the |
480 | code/module that eventually sends the signal. Note that it is also the |
446 | producer side which creates the condvar in most cases, but it isn't |
481 | producer side which creates the condvar in most cases, but it isn't |
447 | uncommon for the consumer to create it as well. |
482 | uncommon for the consumer to create it as well. |
… | |
… | |
567 | |
602 | |
568 | $bool = $cv->ready |
603 | $bool = $cv->ready |
569 | Returns true when the condition is "true", i.e. whether "send" or |
604 | Returns true when the condition is "true", i.e. whether "send" or |
570 | "croak" have been called. |
605 | "croak" have been called. |
571 | |
606 | |
572 | $cb = $cv->cb ([new callback]) |
607 | $cb = $cv->cb ($cb->($cv)) |
573 | This is a mutator function that returns the callback set and |
608 | This is a mutator function that returns the callback set and |
574 | optionally replaces it before doing so. |
609 | optionally replaces it before doing so. |
575 | |
610 | |
576 | The callback will be called when the condition becomes "true", i.e. |
611 | The callback will be called when the condition becomes "true", i.e. |
577 | when "send" or "croak" are called, with the only argument being the |
612 | when "send" or "croak" are called, with the only argument being the |
… | |
… | |
698 | AnyEvent::Util |
733 | AnyEvent::Util |
699 | Contains various utility functions that replace often-used but |
734 | Contains various utility functions that replace often-used but |
700 | blocking functions such as "inet_aton" by event-/callback-based |
735 | blocking functions such as "inet_aton" by event-/callback-based |
701 | versions. |
736 | versions. |
702 | |
737 | |
703 | AnyEvent::Handle |
|
|
704 | Provide read and write buffers and manages watchers for reads and |
|
|
705 | writes. |
|
|
706 | |
|
|
707 | AnyEvent::Socket |
738 | AnyEvent::Socket |
708 | Provides various utility functions for (internet protocol) sockets, |
739 | Provides various utility functions for (internet protocol) sockets, |
709 | addresses and name resolution. Also functions to create non-blocking |
740 | addresses and name resolution. Also functions to create non-blocking |
710 | tcp connections or tcp servers, with IPv6 and SRV record support and |
741 | tcp connections or tcp servers, with IPv6 and SRV record support and |
711 | more. |
742 | more. |
712 | |
743 | |
|
|
744 | AnyEvent::Handle |
|
|
745 | Provide read and write buffers, manages watchers for reads and |
|
|
746 | writes, supports raw and formatted I/O, I/O queued and fully |
|
|
747 | transparent and non-blocking SSL/TLS. |
|
|
748 | |
713 | AnyEvent::DNS |
749 | AnyEvent::DNS |
714 | Provides rich asynchronous DNS resolver capabilities. |
750 | Provides rich asynchronous DNS resolver capabilities. |
715 | |
751 | |
|
|
752 | AnyEvent::HTTP |
|
|
753 | A simple-to-use HTTP library that is capable of making a lot of |
|
|
754 | concurrent HTTP requests. |
|
|
755 | |
716 | AnyEvent::HTTPD |
756 | AnyEvent::HTTPD |
717 | Provides a simple web application server framework. |
757 | Provides a simple web application server framework. |
718 | |
758 | |
719 | AnyEvent::FastPing |
759 | AnyEvent::FastPing |
720 | The fastest ping in the west. |
760 | The fastest ping in the west. |
721 | |
761 | |
|
|
762 | AnyEvent::DBI |
|
|
763 | Executes DBI requests asynchronously in a proxy process. |
|
|
764 | |
|
|
765 | AnyEvent::AIO |
|
|
766 | Truly asynchronous I/O, should be in the toolbox of every event |
|
|
767 | programmer. AnyEvent::AIO transparently fuses IO::AIO and AnyEvent |
|
|
768 | together. |
|
|
769 | |
|
|
770 | AnyEvent::BDB |
|
|
771 | Truly asynchronous Berkeley DB access. AnyEvent::BDB transparently |
|
|
772 | fuses BDB and AnyEvent together. |
|
|
773 | |
|
|
774 | AnyEvent::GPSD |
|
|
775 | A non-blocking interface to gpsd, a daemon delivering GPS |
|
|
776 | information. |
|
|
777 | |
|
|
778 | AnyEvent::IGS |
|
|
779 | A non-blocking interface to the Internet Go Server protocol (used by |
|
|
780 | App::IGS). |
|
|
781 | |
|
|
782 | AnyEvent::IRC |
|
|
783 | AnyEvent based IRC client module family (replacing the older |
722 | Net::IRC3 |
784 | Net::IRC3). |
723 | AnyEvent based IRC client module family. |
|
|
724 | |
785 | |
725 | Net::XMPP2 |
786 | Net::XMPP2 |
726 | AnyEvent based XMPP (Jabber protocol) module family. |
787 | AnyEvent based XMPP (Jabber protocol) module family. |
727 | |
788 | |
728 | Net::FCP |
789 | Net::FCP |
… | |
… | |
733 | High level API for event-based execution flow control. |
794 | High level API for event-based execution flow control. |
734 | |
795 | |
735 | Coro |
796 | Coro |
736 | Has special support for AnyEvent via Coro::AnyEvent. |
797 | Has special support for AnyEvent via Coro::AnyEvent. |
737 | |
798 | |
738 | AnyEvent::AIO, IO::AIO |
|
|
739 | Truly asynchronous I/O, should be in the toolbox of every event |
|
|
740 | programmer. AnyEvent::AIO transparently fuses IO::AIO and AnyEvent |
|
|
741 | together. |
|
|
742 | |
|
|
743 | AnyEvent::BDB, BDB |
|
|
744 | Truly asynchronous Berkeley DB access. AnyEvent::AIO transparently |
|
|
745 | fuses IO::AIO and AnyEvent together. |
|
|
746 | |
|
|
747 | IO::Lambda |
799 | IO::Lambda |
748 | The lambda approach to I/O - don't ask, look there. Can use |
800 | The lambda approach to I/O - don't ask, look there. Can use |
749 | AnyEvent. |
801 | AnyEvent. |
750 | |
802 | |
751 | SUPPLYING YOUR OWN EVENT MODEL INTERFACE |
803 | ERROR AND EXCEPTION HANDLING |
752 | This is an advanced topic that you do not normally need to use AnyEvent |
804 | In general, AnyEvent does not do any error handling - it relies on the |
753 | in a module. This section is only of use to event loop authors who want |
805 | caller to do that if required. The AnyEvent::Strict module (see also the |
754 | to provide AnyEvent compatibility. |
806 | "PERL_ANYEVENT_STRICT" environment variable, below) provides strict |
|
|
807 | checking of all AnyEvent methods, however, which is highly useful during |
|
|
808 | development. |
755 | |
809 | |
756 | If you need to support another event library which isn't directly |
810 | As for exception handling (i.e. runtime errors and exceptions thrown |
757 | supported by AnyEvent, you can supply your own interface to it by |
811 | while executing a callback), this is not only highly event-loop |
758 | pushing, before the first watcher gets created, the package name of the |
812 | specific, but also not in any way wrapped by this module, as this is the |
759 | event module and the package name of the interface to use onto |
813 | job of the main program. |
760 | @AnyEvent::REGISTRY. You can do that before and even without loading |
|
|
761 | AnyEvent, so it is reasonably cheap. |
|
|
762 | |
814 | |
763 | Example: |
815 | The pure perl event loop simply re-throws the exception (usually within |
764 | |
816 | "condvar->recv"), the Event and EV modules call "$Event/EV::DIED->()", |
765 | push @AnyEvent::REGISTRY, [urxvt => urxvt::anyevent::]; |
817 | Glib uses "install_exception_handler" and so on. |
766 | |
|
|
767 | This tells AnyEvent to (literally) use the "urxvt::anyevent::" |
|
|
768 | package/class when it finds the "urxvt" package/module is already |
|
|
769 | loaded. |
|
|
770 | |
|
|
771 | When AnyEvent is loaded and asked to find a suitable event model, it |
|
|
772 | will first check for the presence of urxvt by trying to "use" the |
|
|
773 | "urxvt::anyevent" module. |
|
|
774 | |
|
|
775 | The class should provide implementations for all watcher types. See |
|
|
776 | AnyEvent::Impl::EV (source code), AnyEvent::Impl::Glib (Source code) and |
|
|
777 | so on for actual examples. Use "perldoc -m AnyEvent::Impl::Glib" to see |
|
|
778 | the sources. |
|
|
779 | |
|
|
780 | If you don't provide "signal" and "child" watchers than AnyEvent will |
|
|
781 | provide suitable (hopefully) replacements. |
|
|
782 | |
|
|
783 | The above example isn't fictitious, the *rxvt-unicode* (a.k.a. urxvt) |
|
|
784 | terminal emulator uses the above line as-is. An interface isn't included |
|
|
785 | in AnyEvent because it doesn't make sense outside the embedded |
|
|
786 | interpreter inside *rxvt-unicode*, and it is updated and maintained as |
|
|
787 | part of the *rxvt-unicode* distribution. |
|
|
788 | |
|
|
789 | *rxvt-unicode* also cheats a bit by not providing blocking access to |
|
|
790 | condition variables: code blocking while waiting for a condition will |
|
|
791 | "die". This still works with most modules/usages, and blocking calls |
|
|
792 | must not be done in an interactive application, so it makes sense. |
|
|
793 | |
818 | |
794 | ENVIRONMENT VARIABLES |
819 | ENVIRONMENT VARIABLES |
795 | The following environment variables are used by this module: |
820 | The following environment variables are used by this module or its |
|
|
821 | submodules: |
796 | |
822 | |
797 | "PERL_ANYEVENT_VERBOSE" |
823 | "PERL_ANYEVENT_VERBOSE" |
798 | By default, AnyEvent will be completely silent except in fatal |
824 | By default, AnyEvent will be completely silent except in fatal |
799 | conditions. You can set this environment variable to make AnyEvent |
825 | conditions. You can set this environment variable to make AnyEvent |
800 | more talkative. |
826 | more talkative. |
… | |
… | |
803 | conditions, such as not being able to load the event model specified |
829 | conditions, such as not being able to load the event model specified |
804 | by "PERL_ANYEVENT_MODEL". |
830 | by "PERL_ANYEVENT_MODEL". |
805 | |
831 | |
806 | When set to 2 or higher, cause AnyEvent to report to STDERR which |
832 | When set to 2 or higher, cause AnyEvent to report to STDERR which |
807 | event model it chooses. |
833 | event model it chooses. |
|
|
834 | |
|
|
835 | "PERL_ANYEVENT_STRICT" |
|
|
836 | AnyEvent does not do much argument checking by default, as thorough |
|
|
837 | argument checking is very costly. Setting this variable to a true |
|
|
838 | value will cause AnyEvent to load "AnyEvent::Strict" and then to |
|
|
839 | thoroughly check the arguments passed to most method calls. If it |
|
|
840 | finds any problems it will croak. |
|
|
841 | |
|
|
842 | In other words, enables "strict" mode. |
|
|
843 | |
|
|
844 | Unlike "use strict", it is definitely recommended ot keep it off in |
|
|
845 | production. Keeping "PERL_ANYEVENT_STRICT=1" in your environment |
|
|
846 | while developing programs can be very useful, however. |
808 | |
847 | |
809 | "PERL_ANYEVENT_MODEL" |
848 | "PERL_ANYEVENT_MODEL" |
810 | This can be used to specify the event model to be used by AnyEvent, |
849 | This can be used to specify the event model to be used by AnyEvent, |
811 | before auto detection and -probing kicks in. It must be a string |
850 | before auto detection and -probing kicks in. It must be a string |
812 | consisting entirely of ASCII letters. The string "AnyEvent::Impl::" |
851 | consisting entirely of ASCII letters. The string "AnyEvent::Impl::" |
… | |
… | |
853 | EDNS0 in its DNS requests. |
892 | EDNS0 in its DNS requests. |
854 | |
893 | |
855 | "PERL_ANYEVENT_MAX_FORKS" |
894 | "PERL_ANYEVENT_MAX_FORKS" |
856 | The maximum number of child processes that |
895 | The maximum number of child processes that |
857 | "AnyEvent::Util::fork_call" will create in parallel. |
896 | "AnyEvent::Util::fork_call" will create in parallel. |
|
|
897 | |
|
|
898 | SUPPLYING YOUR OWN EVENT MODEL INTERFACE |
|
|
899 | This is an advanced topic that you do not normally need to use AnyEvent |
|
|
900 | in a module. This section is only of use to event loop authors who want |
|
|
901 | to provide AnyEvent compatibility. |
|
|
902 | |
|
|
903 | If you need to support another event library which isn't directly |
|
|
904 | supported by AnyEvent, you can supply your own interface to it by |
|
|
905 | pushing, before the first watcher gets created, the package name of the |
|
|
906 | event module and the package name of the interface to use onto |
|
|
907 | @AnyEvent::REGISTRY. You can do that before and even without loading |
|
|
908 | AnyEvent, so it is reasonably cheap. |
|
|
909 | |
|
|
910 | Example: |
|
|
911 | |
|
|
912 | push @AnyEvent::REGISTRY, [urxvt => urxvt::anyevent::]; |
|
|
913 | |
|
|
914 | This tells AnyEvent to (literally) use the "urxvt::anyevent::" |
|
|
915 | package/class when it finds the "urxvt" package/module is already |
|
|
916 | loaded. |
|
|
917 | |
|
|
918 | When AnyEvent is loaded and asked to find a suitable event model, it |
|
|
919 | will first check for the presence of urxvt by trying to "use" the |
|
|
920 | "urxvt::anyevent" module. |
|
|
921 | |
|
|
922 | The class should provide implementations for all watcher types. See |
|
|
923 | AnyEvent::Impl::EV (source code), AnyEvent::Impl::Glib (Source code) and |
|
|
924 | so on for actual examples. Use "perldoc -m AnyEvent::Impl::Glib" to see |
|
|
925 | the sources. |
|
|
926 | |
|
|
927 | If you don't provide "signal" and "child" watchers than AnyEvent will |
|
|
928 | provide suitable (hopefully) replacements. |
|
|
929 | |
|
|
930 | The above example isn't fictitious, the *rxvt-unicode* (a.k.a. urxvt) |
|
|
931 | terminal emulator uses the above line as-is. An interface isn't included |
|
|
932 | in AnyEvent because it doesn't make sense outside the embedded |
|
|
933 | interpreter inside *rxvt-unicode*, and it is updated and maintained as |
|
|
934 | part of the *rxvt-unicode* distribution. |
|
|
935 | |
|
|
936 | *rxvt-unicode* also cheats a bit by not providing blocking access to |
|
|
937 | condition variables: code blocking while waiting for a condition will |
|
|
938 | "die". This still works with most modules/usages, and blocking calls |
|
|
939 | must not be done in an interactive application, so it makes sense. |
858 | |
940 | |
859 | EXAMPLE PROGRAM |
941 | EXAMPLE PROGRAM |
860 | The following program uses an I/O watcher to read data from STDIN, a |
942 | The following program uses an I/O watcher to read data from STDIN, a |
861 | timer to display a message once per second, and a condition variable to |
943 | timer to display a message once per second, and a condition variable to |
862 | quit the program when the user enters quit: |
944 | quit the program when the user enters quit: |
… | |
… | |
1274 | |
1356 | |
1275 | use AnyEvent; |
1357 | use AnyEvent; |
1276 | |
1358 | |
1277 | Similar considerations apply to $ENV{PERL_ANYEVENT_VERBOSE}, as that can |
1359 | Similar considerations apply to $ENV{PERL_ANYEVENT_VERBOSE}, as that can |
1278 | be used to probe what backend is used and gain other information (which |
1360 | be used to probe what backend is used and gain other information (which |
1279 | is probably even less useful to an attacker than PERL_ANYEVENT_MODEL). |
1361 | is probably even less useful to an attacker than PERL_ANYEVENT_MODEL), |
|
|
1362 | and $ENV{PERL_ANYEGENT_STRICT}. |
|
|
1363 | |
|
|
1364 | BUGS |
|
|
1365 | Perl 5.8 has numerous memleaks that sometimes hit this module and are |
|
|
1366 | hard to work around. If you suffer from memleaks, first upgrade to Perl |
|
|
1367 | 5.10 and check wether the leaks still show up. (Perl 5.10.0 has other |
|
|
1368 | annoying mamleaks, such as leaking on "map" and "grep" but it is usually |
|
|
1369 | not as pronounced). |
1280 | |
1370 | |
1281 | SEE ALSO |
1371 | SEE ALSO |
1282 | Utility functions: AnyEvent::Util. |
1372 | Utility functions: AnyEvent::Util. |
1283 | |
1373 | |
1284 | Event modules: EV, EV::Glib, Glib::EV, Event, Glib::Event, Glib, Tk, |
1374 | Event modules: EV, EV::Glib, Glib::EV, Event, Glib::Event, Glib, Tk, |