1 | =head1 => NAME |
1 | =head1 NAME |
2 | |
2 | |
3 | AnyEvent - provide framework for multiple event loops |
3 | AnyEvent - provide framework for multiple event loops |
4 | |
4 | |
5 | EV, Event, Glib, Tk, Perl, Event::Lib, Qt, POE - various supported event loops |
5 | EV, 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 | ... |
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13 | }); |
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14 | |
12 | |
15 | my $w = AnyEvent->timer (after => $seconds, cb => sub { |
13 | my $w = AnyEvent->timer (after => $seconds, cb => sub { ... }); |
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14 | my $w = AnyEvent->timer (after => $seconds, interval => $seconds, cb => ... |
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15 | |
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16 | print AnyEvent->now; # prints current event loop time |
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17 | print AnyEvent->time; # think Time::HiRes::time or simply CORE::time. |
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18 | |
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19 | my $w = AnyEvent->signal (signal => "TERM", cb => sub { ... }); |
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20 | |
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21 | my $w = AnyEvent->child (pid => $pid, cb => sub { |
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22 | my ($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 |
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29 | # use a condvar in callback mode: |
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30 | $w->cb (sub { $_[0]->recv }); |
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31 | |
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32 | =head1 INTRODUCTION/TUTORIAL |
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33 | |
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34 | This manpage is mainly a reference manual. If you are interested |
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35 | in a tutorial or some gentle introduction, have a look at the |
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36 | L<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 | |
25 | Glib, POE, IO::Async, Event... CPAN offers event models by the dozen |
40 | Glib, POE, IO::Async, Event... CPAN offers event models by the dozen |
26 | nowadays. So what is different about AnyEvent? |
41 | nowadays. So what is different about AnyEvent? |
27 | |
42 | |
28 | Executive Summary: AnyEvent is I<compatible>, AnyEvent is I<free of |
43 | Executive Summary: AnyEvent is I<compatible>, AnyEvent is I<free of |
29 | policy> and AnyEvent is I<small and efficient>. |
44 | policy> and AnyEvent is I<small and efficient>. |
30 | |
45 | |
31 | First and foremost, I<AnyEvent is not an event model> itself, it only |
46 | First and foremost, I<AnyEvent is not an event model> itself, it only |
32 | interfaces to whatever event model the main program happens to use in a |
47 | interfaces to whatever event model the main program happens to use, in a |
33 | pragmatic way. For event models and certain classes of immortals alike, |
48 | pragmatic way. For event models and certain classes of immortals alike, |
34 | the statement "there can only be one" is a bitter reality: In general, |
49 | the statement "there can only be one" is a bitter reality: In general, |
35 | only one event loop can be active at the same time in a process. AnyEvent |
50 | only one event loop can be active at the same time in a process. AnyEvent |
36 | helps hiding the differences between those event loops. |
51 | cannot change this, but it can hide the differences between those event |
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52 | loops. |
37 | |
53 | |
38 | The goal of AnyEvent is to offer module authors the ability to do event |
54 | The goal of AnyEvent is to offer module authors the ability to do event |
39 | programming (waiting for I/O or timer events) without subscribing to a |
55 | programming (waiting for I/O or timer events) without subscribing to a |
40 | religion, a way of living, and most importantly: without forcing your |
56 | religion, a way of living, and most importantly: without forcing your |
41 | module users into the same thing by forcing them to use the same event |
57 | module users into the same thing by forcing them to use the same event |
42 | model you use. |
58 | model you use. |
43 | |
59 | |
44 | For modules like POE or IO::Async (which is a total misnomer as it is |
60 | For modules like POE or IO::Async (which is a total misnomer as it is |
45 | actually doing all I/O I<synchronously>...), using them in your module is |
61 | actually doing all I/O I<synchronously>...), using them in your module is |
46 | like joining a cult: After you joined, you are dependent on them and you |
62 | like joining a cult: After you joined, you are dependent on them and you |
47 | cannot use anything else, as it is simply incompatible to everything that |
63 | cannot use anything else, as they are simply incompatible to everything |
48 | isn't itself. What's worse, all the potential users of your module are |
64 | that isn't them. What's worse, all the potential users of your |
49 | I<also> forced to use the same event loop you use. |
65 | module are I<also> forced to use the same event loop you use. |
50 | |
66 | |
51 | AnyEvent is different: AnyEvent + POE works fine. AnyEvent + Glib works |
67 | AnyEvent is different: AnyEvent + POE works fine. AnyEvent + Glib works |
52 | fine. AnyEvent + Tk works fine etc. etc. but none of these work together |
68 | fine. AnyEvent + Tk works fine etc. etc. but none of these work together |
53 | with the rest: POE + IO::Async? No go. Tk + Event? No go. Again: if |
69 | with the rest: POE + IO::Async? No go. Tk + Event? No go. Again: if |
54 | your module uses one of those, every user of your module has to use it, |
70 | your module uses one of those, every user of your module has to use it, |
55 | too. But if your module uses AnyEvent, it works transparently with all |
71 | too. But if your module uses AnyEvent, it works transparently with all |
56 | event models it supports (including stuff like POE and IO::Async, as long |
72 | event models it supports (including stuff like IO::Async, as long as those |
57 | as those use one of the supported event loops. It is trivial to add new |
73 | use one of the supported event loops. It is trivial to add new event loops |
58 | event loops to AnyEvent, too, so it is future-proof). |
74 | to AnyEvent, too, so it is future-proof). |
59 | |
75 | |
60 | In addition to being free of having to use I<the one and only true event |
76 | In addition to being free of having to use I<the one and only true event |
61 | model>, AnyEvent also is free of bloat and policy: with POE or similar |
77 | model>, AnyEvent also is free of bloat and policy: with POE or similar |
62 | modules, you get an enormous amount of code and strict rules you have to |
78 | modules, you get an enormous amount of code and strict rules you have to |
63 | follow. AnyEvent, on the other hand, is lean and up to the point, by only |
79 | follow. AnyEvent, on the other hand, is lean and up to the point, by only |
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132 | Many watchers either are used with "recursion" (repeating timers for |
148 | Many watchers either are used with "recursion" (repeating timers for |
133 | example), or need to refer to their watcher object in other ways. |
149 | example), or need to refer to their watcher object in other ways. |
134 | |
150 | |
135 | An any way to achieve that is this pattern: |
151 | An any way to achieve that is this pattern: |
136 | |
152 | |
137 | my $w; $w = AnyEvent->type (arg => value ..., cb => sub { |
153 | my $w; $w = AnyEvent->type (arg => value ..., cb => sub { |
138 | # you can use $w here, for example to undef it |
154 | # you can use $w here, for example to undef it |
139 | undef $w; |
155 | undef $w; |
140 | }); |
156 | }); |
141 | |
157 | |
142 | Note that C<my $w; $w => combination. This is necessary because in Perl, |
158 | Note that C<my $w; $w => combination. This is necessary because in Perl, |
143 | my variables are only visible after the statement in which they are |
159 | my variables are only visible after the statement in which they are |
144 | declared. |
160 | declared. |
145 | |
161 | |
146 | =head2 I/O WATCHERS |
162 | =head2 I/O WATCHERS |
147 | |
163 | |
148 | You can create an I/O watcher by calling the C<< AnyEvent->io >> method |
164 | You can create an I/O watcher by calling the C<< AnyEvent->io >> method |
149 | with the following mandatory key-value pairs as arguments: |
165 | with the following mandatory key-value pairs as arguments: |
150 | |
166 | |
151 | C<fh> the Perl I<file handle> (I<not> file descriptor) to watch |
167 | C<fh> the Perl I<file handle> (I<not> file descriptor) to watch for events |
152 | for 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> |
153 | which creates a watcher waiting for "r"eadable or "w"ritable events, |
169 | must be a string that is either C<r> or C<w>, which creates a watcher |
154 | respectively. C<cb> is the callback to invoke each time the file handle |
170 | waiting for "r"eadable or "w"ritable events, respectively. C<cb> is the |
155 | becomes ready. |
171 | callback to invoke each time the file handle becomes ready. |
156 | |
172 | |
157 | Although the callback might get passed parameters, their value and |
173 | Although the callback might get passed parameters, their value and |
158 | presence is undefined and you cannot rely on them. Portable AnyEvent |
174 | presence is undefined and you cannot rely on them. Portable AnyEvent |
159 | callbacks cannot use arguments passed to I/O watcher callbacks. |
175 | callbacks cannot use arguments passed to I/O watcher callbacks. |
160 | |
176 | |
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164 | |
180 | |
165 | Some event loops issue spurious readyness notifications, so you should |
181 | Some event loops issue spurious readyness notifications, so you should |
166 | always use non-blocking calls when reading/writing from/to your file |
182 | always use non-blocking calls when reading/writing from/to your file |
167 | handles. |
183 | handles. |
168 | |
184 | |
169 | Example: |
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170 | |
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171 | # wait for readability of STDIN, then read a line and disable the watcher |
185 | Example: wait for readability of STDIN, then read a line and disable the |
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186 | watcher. |
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187 | |
172 | my $w; $w = AnyEvent->io (fh => \*STDIN, poll => 'r', cb => sub { |
188 | my $w; $w = AnyEvent->io (fh => \*STDIN, poll => 'r', cb => sub { |
173 | chomp (my $input = <STDIN>); |
189 | chomp (my $input = <STDIN>); |
174 | warn "read: $input\n"; |
190 | warn "read: $input\n"; |
175 | undef $w; |
191 | undef $w; |
176 | }); |
192 | }); |
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186 | |
202 | |
187 | Although the callback might get passed parameters, their value and |
203 | Although the callback might get passed parameters, their value and |
188 | presence is undefined and you cannot rely on them. Portable AnyEvent |
204 | presence is undefined and you cannot rely on them. Portable AnyEvent |
189 | callbacks cannot use arguments passed to time watcher callbacks. |
205 | callbacks cannot use arguments passed to time watcher callbacks. |
190 | |
206 | |
191 | The timer callback will be invoked at most once: if you want a repeating |
207 | The callback will normally be invoked once only. If you specify another |
192 | timer you have to create a new watcher (this is a limitation by both Tk |
208 | parameter, C<interval>, as a strictly positive number (> 0), then the |
193 | and Glib). |
209 | callback will be invoked regularly at that interval (in fractional |
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210 | seconds) after the first invocation. If C<interval> is specified with a |
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211 | false value, then it is treated as if it were missing. |
194 | |
212 | |
195 | Example: |
213 | The callback will be rescheduled before invoking the callback, but no |
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214 | attempt is done to avoid timer drift in most backends, so the interval is |
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215 | only approximate. |
196 | |
216 | |
197 | # fire an event after 7.7 seconds |
217 | Example: fire an event after 7.7 seconds. |
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218 | |
198 | my $w = AnyEvent->timer (after => 7.7, cb => sub { |
219 | my $w = AnyEvent->timer (after => 7.7, cb => sub { |
199 | warn "timeout\n"; |
220 | warn "timeout\n"; |
200 | }); |
221 | }); |
201 | |
222 | |
202 | # to cancel the timer: |
223 | # to cancel the timer: |
203 | undef $w; |
224 | undef $w; |
204 | |
225 | |
205 | Example 2: |
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206 | |
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207 | # fire an event after 0.5 seconds, then roughly every second |
226 | Example 2: fire an event after 0.5 seconds, then roughly every second. |
208 | my $w; |
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209 | |
227 | |
210 | my $cb = sub { |
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211 | # cancel the old timer while creating a new one |
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212 | $w = AnyEvent->timer (after => 1, cb => $cb); |
228 | my $w = AnyEvent->timer (after => 0.5, interval => 1, cb => sub { |
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229 | warn "timeout\n"; |
213 | }; |
230 | }; |
214 | |
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215 | # start the "loop" by creating the first watcher |
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216 | $w = AnyEvent->timer (after => 0.5, cb => $cb); |
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217 | |
231 | |
218 | =head3 TIMING ISSUES |
232 | =head3 TIMING ISSUES |
219 | |
233 | |
220 | There are two ways to handle timers: based on real time (relative, "fire |
234 | There are two ways to handle timers: based on real time (relative, "fire |
221 | in 10 seconds") and based on wallclock time (absolute, "fire at 12 |
235 | in 10 seconds") and based on wallclock time (absolute, "fire at 12 |
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299 | =back |
313 | =back |
300 | |
314 | |
301 | =head2 SIGNAL WATCHERS |
315 | =head2 SIGNAL WATCHERS |
302 | |
316 | |
303 | You can watch for signals using a signal watcher, C<signal> is the signal |
317 | You can watch for signals using a signal watcher, C<signal> is the signal |
304 | I<name> without any C<SIG> prefix, C<cb> is the Perl callback to |
318 | I<name> in uppercase and without any C<SIG> prefix, C<cb> is the Perl |
305 | be invoked whenever a signal occurs. |
319 | callback to be invoked whenever a signal occurs. |
306 | |
320 | |
307 | Although the callback might get passed parameters, their value and |
321 | Although the callback might get passed parameters, their value and |
308 | presence is undefined and you cannot rely on them. Portable AnyEvent |
322 | presence is undefined and you cannot rely on them. Portable AnyEvent |
309 | callbacks cannot use arguments passed to signal watcher callbacks. |
323 | callbacks cannot use arguments passed to signal watcher callbacks. |
310 | |
324 | |
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346 | AnyEvent program, you I<have> to create at least one watcher before you |
360 | AnyEvent program, you I<have> to create at least one watcher before you |
347 | C<fork> the child (alternatively, you can call C<AnyEvent::detect>). |
361 | C<fork> the child (alternatively, you can call C<AnyEvent::detect>). |
348 | |
362 | |
349 | Example: fork a process and wait for it |
363 | Example: fork a process and wait for it |
350 | |
364 | |
351 | my $done = AnyEvent->condvar; |
365 | my $done = AnyEvent->condvar; |
352 | |
366 | |
353 | my $pid = fork or exit 5; |
367 | my $pid = fork or exit 5; |
354 | |
368 | |
355 | my $w = AnyEvent->child ( |
369 | my $w = AnyEvent->child ( |
356 | pid => $pid, |
370 | pid => $pid, |
357 | cb => sub { |
371 | cb => sub { |
358 | my ($pid, $status) = @_; |
372 | my ($pid, $status) = @_; |
359 | warn "pid $pid exited with status $status"; |
373 | warn "pid $pid exited with status $status"; |
360 | $done->send; |
374 | $done->send; |
361 | }, |
375 | }, |
362 | ); |
376 | ); |
363 | |
377 | |
364 | # do something else, then wait for process exit |
378 | # do something else, then wait for process exit |
365 | $done->recv; |
379 | $done->recv; |
366 | |
380 | |
367 | =head2 CONDITION VARIABLES |
381 | =head2 CONDITION VARIABLES |
368 | |
382 | |
369 | If you are familiar with some event loops you will know that all of them |
383 | If you are familiar with some event loops you will know that all of them |
370 | require you to run some blocking "loop", "run" or similar function that |
384 | require you to run some blocking "loop", "run" or similar function that |
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376 | The instrument to do that is called a "condition variable", so called |
390 | The instrument to do that is called a "condition variable", so called |
377 | because they represent a condition that must become true. |
391 | because they represent a condition that must become true. |
378 | |
392 | |
379 | Condition variables can be created by calling the C<< AnyEvent->condvar |
393 | Condition variables can be created by calling the C<< AnyEvent->condvar |
380 | >> method, usually without arguments. The only argument pair allowed is |
394 | >> method, usually without arguments. The only argument pair allowed is |
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395 | |
381 | C<cb>, which specifies a callback to be called when the condition variable |
396 | C<cb>, which specifies a callback to be called when the condition variable |
382 | becomes true. |
397 | becomes true, with the condition variable as the first argument (but not |
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398 | the results). |
383 | |
399 | |
384 | After creation, the condition variable is "false" until it becomes "true" |
400 | After creation, the condition variable is "false" until it becomes "true" |
385 | by calling the C<send> method (or calling the condition variable as if it |
401 | by calling the C<send> method (or calling the condition variable as if it |
386 | were a callback, read about the caveats in the description for the C<< |
402 | were a callback, read about the caveats in the description for the C<< |
387 | ->send >> method). |
403 | ->send >> method). |
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443 | |
459 | |
444 | my $done = AnyEvent->condvar; |
460 | my $done = AnyEvent->condvar; |
445 | my $delay = AnyEvent->timer (after => 5, cb => $done); |
461 | my $delay = AnyEvent->timer (after => 5, cb => $done); |
446 | $done->recv; |
462 | $done->recv; |
447 | |
463 | |
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464 | Example: Imagine an API that returns a condvar and doesn't support |
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465 | callbacks. This is how you make a synchronous call, for example from |
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466 | the main program: |
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467 | |
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468 | use AnyEvent::CouchDB; |
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469 | |
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470 | ... |
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471 | |
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472 | my @info = $couchdb->info->recv; |
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473 | |
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474 | And this is how you would just ste a callback to be called whenever the |
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475 | results are available: |
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476 | |
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477 | $couchdb->info->cb (sub { |
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478 | my @info = $_[0]->recv; |
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479 | }); |
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480 | |
448 | =head3 METHODS FOR PRODUCERS |
481 | =head3 METHODS FOR PRODUCERS |
449 | |
482 | |
450 | These methods should only be used by the producing side, i.e. the |
483 | These methods should only be used by the producing side, i.e. the |
451 | code/module that eventually sends the signal. Note that it is also |
484 | code/module that eventually sends the signal. Note that it is also |
452 | the producer side which creates the condvar in most cases, but it isn't |
485 | the producer side which creates the condvar in most cases, but it isn't |
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585 | =item $bool = $cv->ready |
618 | =item $bool = $cv->ready |
586 | |
619 | |
587 | Returns true when the condition is "true", i.e. whether C<send> or |
620 | Returns true when the condition is "true", i.e. whether C<send> or |
588 | C<croak> have been called. |
621 | C<croak> have been called. |
589 | |
622 | |
590 | =item $cb = $cv->cb ([new callback]) |
623 | =item $cb = $cv->cb ($cb->($cv)) |
591 | |
624 | |
592 | This is a mutator function that returns the callback set and optionally |
625 | This is a mutator function that returns the callback set and optionally |
593 | replaces it before doing so. |
626 | replaces it before doing so. |
594 | |
627 | |
595 | The callback will be called when the condition becomes "true", i.e. when |
628 | The callback will be called when the condition becomes "true", i.e. when |
596 | C<send> or C<croak> are called. Calling C<recv> inside the callback |
629 | C<send> or C<croak> are called, with the only argument being the condition |
597 | or at any later time is guaranteed not to block. |
630 | variable itself. Calling C<recv> inside the callback or at any later time |
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631 | is guaranteed not to block. |
598 | |
632 | |
599 | =back |
633 | =back |
600 | |
634 | |
601 | =head1 GLOBAL VARIABLES AND FUNCTIONS |
635 | =head1 GLOBAL VARIABLES AND FUNCTIONS |
602 | |
636 | |
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731 | =item L<AnyEvent::Util> |
765 | =item L<AnyEvent::Util> |
732 | |
766 | |
733 | Contains various utility functions that replace often-used but blocking |
767 | Contains various utility functions that replace often-used but blocking |
734 | functions such as C<inet_aton> by event-/callback-based versions. |
768 | functions such as C<inet_aton> by event-/callback-based versions. |
735 | |
769 | |
736 | =item L<AnyEvent::Handle> |
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737 | |
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738 | Provide read and write buffers and manages watchers for reads and writes. |
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739 | |
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740 | =item L<AnyEvent::Socket> |
770 | =item L<AnyEvent::Socket> |
741 | |
771 | |
742 | Provides various utility functions for (internet protocol) sockets, |
772 | Provides various utility functions for (internet protocol) sockets, |
743 | addresses and name resolution. Also functions to create non-blocking tcp |
773 | addresses and name resolution. Also functions to create non-blocking tcp |
744 | connections or tcp servers, with IPv6 and SRV record support and more. |
774 | connections or tcp servers, with IPv6 and SRV record support and more. |
745 | |
775 | |
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776 | =item L<AnyEvent::Handle> |
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777 | |
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778 | Provide read and write buffers, manages watchers for reads and writes, |
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779 | supports raw and formatted I/O, I/O queued and fully transparent and |
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780 | non-blocking SSL/TLS. |
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781 | |
746 | =item L<AnyEvent::DNS> |
782 | =item L<AnyEvent::DNS> |
747 | |
783 | |
748 | Provides rich asynchronous DNS resolver capabilities. |
784 | Provides rich asynchronous DNS resolver capabilities. |
749 | |
785 | |
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786 | =item L<AnyEvent::HTTP> |
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787 | |
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788 | A simple-to-use HTTP library that is capable of making a lot of concurrent |
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789 | HTTP requests. |
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790 | |
750 | =item L<AnyEvent::HTTPD> |
791 | =item L<AnyEvent::HTTPD> |
751 | |
792 | |
752 | Provides a simple web application server framework. |
793 | Provides a simple web application server framework. |
753 | |
794 | |
754 | =item L<AnyEvent::FastPing> |
795 | =item L<AnyEvent::FastPing> |
755 | |
796 | |
756 | The fastest ping in the west. |
797 | The fastest ping in the west. |
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798 | |
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799 | =item L<AnyEvent::DBI> |
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800 | |
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801 | Executes L<DBI> requests asynchronously in a proxy process. |
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802 | |
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803 | =item L<AnyEvent::AIO> |
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804 | |
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805 | Truly asynchronous I/O, should be in the toolbox of every event |
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806 | programmer. AnyEvent::AIO transparently fuses L<IO::AIO> and AnyEvent |
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807 | together. |
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808 | |
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809 | =item L<AnyEvent::BDB> |
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810 | |
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811 | Truly asynchronous Berkeley DB access. AnyEvent::BDB transparently fuses |
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812 | L<BDB> and AnyEvent together. |
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813 | |
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814 | =item L<AnyEvent::GPSD> |
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815 | |
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816 | A non-blocking interface to gpsd, a daemon delivering GPS information. |
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817 | |
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818 | =item L<AnyEvent::IGS> |
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819 | |
|
|
820 | A non-blocking interface to the Internet Go Server protocol (used by |
|
|
821 | L<App::IGS>). |
757 | |
822 | |
758 | =item L<Net::IRC3> |
823 | =item L<Net::IRC3> |
759 | |
824 | |
760 | AnyEvent based IRC client module family. |
825 | AnyEvent based IRC client module family. |
761 | |
826 | |
… | |
… | |
774 | |
839 | |
775 | =item L<Coro> |
840 | =item L<Coro> |
776 | |
841 | |
777 | Has special support for AnyEvent via L<Coro::AnyEvent>. |
842 | Has special support for AnyEvent via L<Coro::AnyEvent>. |
778 | |
843 | |
779 | =item L<AnyEvent::AIO>, L<IO::AIO> |
|
|
780 | |
|
|
781 | Truly asynchronous I/O, should be in the toolbox of every event |
|
|
782 | programmer. AnyEvent::AIO transparently fuses IO::AIO and AnyEvent |
|
|
783 | together. |
|
|
784 | |
|
|
785 | =item L<AnyEvent::BDB>, L<BDB> |
|
|
786 | |
|
|
787 | Truly asynchronous Berkeley DB access. AnyEvent::AIO transparently fuses |
|
|
788 | IO::AIO and AnyEvent together. |
|
|
789 | |
|
|
790 | =item L<IO::Lambda> |
844 | =item L<IO::Lambda> |
791 | |
845 | |
792 | The lambda approach to I/O - don't ask, look there. Can use AnyEvent. |
846 | The lambda approach to I/O - don't ask, look there. Can use AnyEvent. |
793 | |
847 | |
794 | =back |
848 | =back |
… | |
… | |
796 | =cut |
850 | =cut |
797 | |
851 | |
798 | package AnyEvent; |
852 | package AnyEvent; |
799 | |
853 | |
800 | no warnings; |
854 | no warnings; |
801 | use strict; |
855 | use strict qw(vars subs); |
802 | |
856 | |
803 | use Carp; |
857 | use Carp; |
804 | |
858 | |
805 | our $VERSION = 4.11; |
859 | our $VERSION = 4.233; |
806 | our $MODEL; |
860 | our $MODEL; |
807 | |
861 | |
808 | our $AUTOLOAD; |
862 | our $AUTOLOAD; |
809 | our @ISA; |
863 | our @ISA; |
810 | |
864 | |
… | |
… | |
913 | $MODEL |
967 | $MODEL |
914 | or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib."; |
968 | or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib."; |
915 | } |
969 | } |
916 | } |
970 | } |
917 | |
971 | |
|
|
972 | push @{"$MODEL\::ISA"}, "AnyEvent::Base"; |
|
|
973 | |
918 | unshift @ISA, $MODEL; |
974 | unshift @ISA, $MODEL; |
919 | push @{"$MODEL\::ISA"}, "AnyEvent::Base"; |
975 | |
|
|
976 | require AnyEvent::Strict if $ENV{PERL_ANYEVENT_STRICT}; |
920 | |
977 | |
921 | (shift @post_detect)->() while @post_detect; |
978 | (shift @post_detect)->() while @post_detect; |
922 | } |
979 | } |
923 | |
980 | |
924 | $MODEL |
981 | $MODEL |
… | |
… | |
934 | |
991 | |
935 | my $class = shift; |
992 | my $class = shift; |
936 | $class->$func (@_); |
993 | $class->$func (@_); |
937 | } |
994 | } |
938 | |
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). |
|
|
999 | sub _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 | |
939 | package AnyEvent::Base; |
1017 | package AnyEvent::Base; |
940 | |
1018 | |
941 | # default implementation for now and time |
1019 | # default implementation for now and time |
942 | |
1020 | |
943 | use Time::HiRes (); |
1021 | BEGIN { |
|
|
1022 | if (eval "use Time::HiRes (); time (); 1") { |
|
|
1023 | *_time = \&Time::HiRes::time; |
|
|
1024 | # if (eval "use POSIX (); (POSIX::times())... |
|
|
1025 | } else { |
|
|
1026 | *_time = \&CORE::time; # epic fail |
|
|
1027 | } |
|
|
1028 | } |
944 | |
1029 | |
945 | sub time { Time::HiRes::time } |
1030 | sub time { _time } |
946 | sub now { Time::HiRes::time } |
1031 | sub now { _time } |
947 | |
1032 | |
948 | # default implementation for ->condvar |
1033 | # default implementation for ->condvar |
949 | |
1034 | |
950 | sub condvar { |
1035 | sub condvar { |
951 | bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, AnyEvent::CondVar:: |
1036 | bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, AnyEvent::CondVar:: |
… | |
… | |
972 | sub AnyEvent::Base::Signal::DESTROY { |
1057 | sub AnyEvent::Base::Signal::DESTROY { |
973 | my ($signal, $cb) = @{$_[0]}; |
1058 | my ($signal, $cb) = @{$_[0]}; |
974 | |
1059 | |
975 | delete $SIG_CB{$signal}{$cb}; |
1060 | delete $SIG_CB{$signal}{$cb}; |
976 | |
1061 | |
977 | $SIG{$signal} = 'DEFAULT' unless keys %{ $SIG_CB{$signal} }; |
1062 | delete $SIG{$signal} unless keys %{ $SIG_CB{$signal} }; |
978 | } |
1063 | } |
979 | |
1064 | |
980 | # default implementation for ->child |
1065 | # default implementation for ->child |
981 | |
1066 | |
982 | our %PID_CB; |
1067 | our %PID_CB; |
… | |
… | |
1090 | |
1175 | |
1091 | # undocumented/compatibility with pre-3.4 |
1176 | # undocumented/compatibility with pre-3.4 |
1092 | *broadcast = \&send; |
1177 | *broadcast = \&send; |
1093 | *wait = \&_wait; |
1178 | *wait = \&_wait; |
1094 | |
1179 | |
|
|
1180 | =head1 ERROR AND EXCEPTION HANDLING |
|
|
1181 | |
|
|
1182 | In general, AnyEvent does not do any error handling - it relies on the |
|
|
1183 | caller to do that if required. The L<AnyEvent::Strict> module (see also |
|
|
1184 | the C<PERL_ANYEVENT_STRICT> environment variable, below) provides strict |
|
|
1185 | checking of all AnyEvent methods, however, which is highly useful during |
|
|
1186 | development. |
|
|
1187 | |
|
|
1188 | As for exception handling (i.e. runtime errors and exceptions thrown while |
|
|
1189 | executing a callback), this is not only highly event-loop specific, but |
|
|
1190 | also not in any way wrapped by this module, as this is the job of the main |
|
|
1191 | program. |
|
|
1192 | |
|
|
1193 | The pure perl event loop simply re-throws the exception (usually |
|
|
1194 | within C<< condvar->recv >>), the L<Event> and L<EV> modules call C<< |
|
|
1195 | $Event/EV::DIED->() >>, L<Glib> uses C<< install_exception_handler >> and |
|
|
1196 | so on. |
|
|
1197 | |
|
|
1198 | =head1 ENVIRONMENT VARIABLES |
|
|
1199 | |
|
|
1200 | The following environment variables are used by this module or its |
|
|
1201 | submodules: |
|
|
1202 | |
|
|
1203 | =over 4 |
|
|
1204 | |
|
|
1205 | =item C<PERL_ANYEVENT_VERBOSE> |
|
|
1206 | |
|
|
1207 | By default, AnyEvent will be completely silent except in fatal |
|
|
1208 | conditions. You can set this environment variable to make AnyEvent more |
|
|
1209 | talkative. |
|
|
1210 | |
|
|
1211 | When set to C<1> or higher, causes AnyEvent to warn about unexpected |
|
|
1212 | conditions, such as not being able to load the event model specified by |
|
|
1213 | C<PERL_ANYEVENT_MODEL>. |
|
|
1214 | |
|
|
1215 | When set to C<2> or higher, cause AnyEvent to report to STDERR which event |
|
|
1216 | model it chooses. |
|
|
1217 | |
|
|
1218 | =item C<PERL_ANYEVENT_STRICT> |
|
|
1219 | |
|
|
1220 | AnyEvent does not do much argument checking by default, as thorough |
|
|
1221 | argument checking is very costly. Setting this variable to a true value |
|
|
1222 | will cause AnyEvent to load C<AnyEvent::Strict> and then to thoroughly |
|
|
1223 | check the arguments passed to most method calls. If it finds any problems |
|
|
1224 | it will croak. |
|
|
1225 | |
|
|
1226 | In other words, enables "strict" mode. |
|
|
1227 | |
|
|
1228 | Unlike C<use strict>, it is definitely recommended ot keep it off in |
|
|
1229 | production. Keeping C<PERL_ANYEVENT_STRICT=1> in your environment while |
|
|
1230 | developing programs can be very useful, however. |
|
|
1231 | |
|
|
1232 | =item C<PERL_ANYEVENT_MODEL> |
|
|
1233 | |
|
|
1234 | This can be used to specify the event model to be used by AnyEvent, before |
|
|
1235 | auto detection and -probing kicks in. It must be a string consisting |
|
|
1236 | entirely of ASCII letters. The string C<AnyEvent::Impl::> gets prepended |
|
|
1237 | and the resulting module name is loaded and if the load was successful, |
|
|
1238 | used as event model. If it fails to load AnyEvent will proceed with |
|
|
1239 | auto detection and -probing. |
|
|
1240 | |
|
|
1241 | This functionality might change in future versions. |
|
|
1242 | |
|
|
1243 | For example, to force the pure perl model (L<AnyEvent::Impl::Perl>) you |
|
|
1244 | could start your program like this: |
|
|
1245 | |
|
|
1246 | PERL_ANYEVENT_MODEL=Perl perl ... |
|
|
1247 | |
|
|
1248 | =item C<PERL_ANYEVENT_PROTOCOLS> |
|
|
1249 | |
|
|
1250 | Used by both L<AnyEvent::DNS> and L<AnyEvent::Socket> to determine preferences |
|
|
1251 | for IPv4 or IPv6. The default is unspecified (and might change, or be the result |
|
|
1252 | of auto probing). |
|
|
1253 | |
|
|
1254 | Must be set to a comma-separated list of protocols or address families, |
|
|
1255 | current supported: C<ipv4> and C<ipv6>. Only protocols mentioned will be |
|
|
1256 | used, and preference will be given to protocols mentioned earlier in the |
|
|
1257 | list. |
|
|
1258 | |
|
|
1259 | This variable can effectively be used for denial-of-service attacks |
|
|
1260 | against local programs (e.g. when setuid), although the impact is likely |
|
|
1261 | small, as the program has to handle connection errors already- |
|
|
1262 | |
|
|
1263 | Examples: C<PERL_ANYEVENT_PROTOCOLS=ipv4,ipv6> - prefer IPv4 over IPv6, |
|
|
1264 | but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4> |
|
|
1265 | - only support IPv4, never try to resolve or contact IPv6 |
|
|
1266 | addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or |
|
|
1267 | IPv6, but prefer IPv6 over IPv4. |
|
|
1268 | |
|
|
1269 | =item C<PERL_ANYEVENT_EDNS0> |
|
|
1270 | |
|
|
1271 | Used by L<AnyEvent::DNS> to decide whether to use the EDNS0 extension |
|
|
1272 | for DNS. This extension is generally useful to reduce DNS traffic, but |
|
|
1273 | some (broken) firewalls drop such DNS packets, which is why it is off by |
|
|
1274 | default. |
|
|
1275 | |
|
|
1276 | Setting this variable to C<1> will cause L<AnyEvent::DNS> to announce |
|
|
1277 | EDNS0 in its DNS requests. |
|
|
1278 | |
|
|
1279 | =item C<PERL_ANYEVENT_MAX_FORKS> |
|
|
1280 | |
|
|
1281 | The maximum number of child processes that C<AnyEvent::Util::fork_call> |
|
|
1282 | will create in parallel. |
|
|
1283 | |
|
|
1284 | =back |
|
|
1285 | |
1095 | =head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE |
1286 | =head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE |
1096 | |
1287 | |
1097 | This is an advanced topic that you do not normally need to use AnyEvent in |
1288 | This is an advanced topic that you do not normally need to use AnyEvent in |
1098 | a module. This section is only of use to event loop authors who want to |
1289 | a module. This section is only of use to event loop authors who want to |
1099 | provide AnyEvent compatibility. |
1290 | provide AnyEvent compatibility. |
… | |
… | |
1132 | |
1323 | |
1133 | I<rxvt-unicode> also cheats a bit by not providing blocking access to |
1324 | I<rxvt-unicode> also cheats a bit by not providing blocking access to |
1134 | condition variables: code blocking while waiting for a condition will |
1325 | condition variables: code blocking while waiting for a condition will |
1135 | C<die>. This still works with most modules/usages, and blocking calls must |
1326 | C<die>. This still works with most modules/usages, and blocking calls must |
1136 | not be done in an interactive application, so it makes sense. |
1327 | not be done in an interactive application, so it makes sense. |
1137 | |
|
|
1138 | =head1 ENVIRONMENT VARIABLES |
|
|
1139 | |
|
|
1140 | The following environment variables are used by this module: |
|
|
1141 | |
|
|
1142 | =over 4 |
|
|
1143 | |
|
|
1144 | =item C<PERL_ANYEVENT_VERBOSE> |
|
|
1145 | |
|
|
1146 | By default, AnyEvent will be completely silent except in fatal |
|
|
1147 | conditions. You can set this environment variable to make AnyEvent more |
|
|
1148 | talkative. |
|
|
1149 | |
|
|
1150 | When set to C<1> or higher, causes AnyEvent to warn about unexpected |
|
|
1151 | conditions, such as not being able to load the event model specified by |
|
|
1152 | C<PERL_ANYEVENT_MODEL>. |
|
|
1153 | |
|
|
1154 | When set to C<2> or higher, cause AnyEvent to report to STDERR which event |
|
|
1155 | model it chooses. |
|
|
1156 | |
|
|
1157 | =item C<PERL_ANYEVENT_MODEL> |
|
|
1158 | |
|
|
1159 | This can be used to specify the event model to be used by AnyEvent, before |
|
|
1160 | auto detection and -probing kicks in. It must be a string consisting |
|
|
1161 | entirely of ASCII letters. The string C<AnyEvent::Impl::> gets prepended |
|
|
1162 | and the resulting module name is loaded and if the load was successful, |
|
|
1163 | used as event model. If it fails to load AnyEvent will proceed with |
|
|
1164 | auto detection and -probing. |
|
|
1165 | |
|
|
1166 | This functionality might change in future versions. |
|
|
1167 | |
|
|
1168 | For example, to force the pure perl model (L<AnyEvent::Impl::Perl>) you |
|
|
1169 | could start your program like this: |
|
|
1170 | |
|
|
1171 | PERL_ANYEVENT_MODEL=Perl perl ... |
|
|
1172 | |
|
|
1173 | =item C<PERL_ANYEVENT_PROTOCOLS> |
|
|
1174 | |
|
|
1175 | Used by both L<AnyEvent::DNS> and L<AnyEvent::Socket> to determine preferences |
|
|
1176 | for IPv4 or IPv6. The default is unspecified (and might change, or be the result |
|
|
1177 | of auto probing). |
|
|
1178 | |
|
|
1179 | Must be set to a comma-separated list of protocols or address families, |
|
|
1180 | current supported: C<ipv4> and C<ipv6>. Only protocols mentioned will be |
|
|
1181 | used, and preference will be given to protocols mentioned earlier in the |
|
|
1182 | list. |
|
|
1183 | |
|
|
1184 | This variable can effectively be used for denial-of-service attacks |
|
|
1185 | against local programs (e.g. when setuid), although the impact is likely |
|
|
1186 | small, as the program has to handle connection errors already- |
|
|
1187 | |
|
|
1188 | Examples: C<PERL_ANYEVENT_PROTOCOLS=ipv4,ipv6> - prefer IPv4 over IPv6, |
|
|
1189 | but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4> |
|
|
1190 | - only support IPv4, never try to resolve or contact IPv6 |
|
|
1191 | addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or |
|
|
1192 | IPv6, but prefer IPv6 over IPv4. |
|
|
1193 | |
|
|
1194 | =item C<PERL_ANYEVENT_EDNS0> |
|
|
1195 | |
|
|
1196 | Used by L<AnyEvent::DNS> to decide whether to use the EDNS0 extension |
|
|
1197 | for DNS. This extension is generally useful to reduce DNS traffic, but |
|
|
1198 | some (broken) firewalls drop such DNS packets, which is why it is off by |
|
|
1199 | default. |
|
|
1200 | |
|
|
1201 | Setting this variable to C<1> will cause L<AnyEvent::DNS> to announce |
|
|
1202 | EDNS0 in its DNS requests. |
|
|
1203 | |
|
|
1204 | =item C<PERL_ANYEVENT_MAX_FORKS> |
|
|
1205 | |
|
|
1206 | The maximum number of child processes that C<AnyEvent::Util::fork_call> |
|
|
1207 | will create in parallel. |
|
|
1208 | |
|
|
1209 | =back |
|
|
1210 | |
1328 | |
1211 | =head1 EXAMPLE PROGRAM |
1329 | =head1 EXAMPLE PROGRAM |
1212 | |
1330 | |
1213 | The following program uses an I/O watcher to read data from STDIN, a timer |
1331 | The following program uses an I/O watcher to read data from STDIN, a timer |
1214 | to display a message once per second, and a condition variable to quit the |
1332 | to display a message once per second, and a condition variable to quit the |
… | |
… | |
1651 | specified in the variable. |
1769 | specified in the variable. |
1652 | |
1770 | |
1653 | You can make AnyEvent completely ignore this variable by deleting it |
1771 | You can make AnyEvent completely ignore this variable by deleting it |
1654 | before the first watcher gets created, e.g. with a C<BEGIN> block: |
1772 | before the first watcher gets created, e.g. with a C<BEGIN> block: |
1655 | |
1773 | |
1656 | BEGIN { delete $ENV{PERL_ANYEVENT_MODEL} } |
1774 | BEGIN { delete $ENV{PERL_ANYEVENT_MODEL} } |
1657 | |
1775 | |
1658 | use AnyEvent; |
1776 | use AnyEvent; |
1659 | |
1777 | |
1660 | Similar considerations apply to $ENV{PERL_ANYEVENT_VERBOSE}, as that can |
1778 | Similar considerations apply to $ENV{PERL_ANYEVENT_VERBOSE}, as that can |
1661 | be used to probe what backend is used and gain other information (which is |
1779 | be used to probe what backend is used and gain other information (which is |
1662 | probably even less useful to an attacker than PERL_ANYEVENT_MODEL). |
1780 | probably even less useful to an attacker than PERL_ANYEVENT_MODEL), and |
|
|
1781 | $ENV{PERL_ANYEGENT_STRICT}. |
|
|
1782 | |
|
|
1783 | |
|
|
1784 | =head1 BUGS |
|
|
1785 | |
|
|
1786 | Perl 5.8 has numerous memleaks that sometimes hit this module and are hard |
|
|
1787 | to work around. If you suffer from memleaks, first upgrade to Perl 5.10 |
|
|
1788 | and check wether the leaks still show up. (Perl 5.10.0 has other annoying |
|
|
1789 | mamleaks, such as leaking on C<map> and C<grep> but it is usually not as |
|
|
1790 | pronounced). |
1663 | |
1791 | |
1664 | |
1792 | |
1665 | =head1 SEE ALSO |
1793 | =head1 SEE ALSO |
1666 | |
1794 | |
1667 | Utility functions: L<AnyEvent::Util>. |
1795 | Utility functions: L<AnyEvent::Util>. |
… | |
… | |
1684 | Nontrivial usage examples: L<Net::FCP>, L<Net::XMPP2>, L<AnyEvent::DNS>. |
1812 | Nontrivial usage examples: L<Net::FCP>, L<Net::XMPP2>, L<AnyEvent::DNS>. |
1685 | |
1813 | |
1686 | |
1814 | |
1687 | =head1 AUTHOR |
1815 | =head1 AUTHOR |
1688 | |
1816 | |
1689 | Marc Lehmann <schmorp@schmorp.de> |
1817 | Marc Lehmann <schmorp@schmorp.de> |
1690 | http://home.schmorp.de/ |
1818 | http://home.schmorp.de/ |
1691 | |
1819 | |
1692 | =cut |
1820 | =cut |
1693 | |
1821 | |
1694 | 1 |
1822 | 1 |
1695 | |
1823 | |