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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233 | timers. |
247 | timers. |
234 | |
248 | |
235 | AnyEvent always prefers relative timers, if available, matching the |
249 | AnyEvent always prefers relative timers, if available, matching the |
236 | AnyEvent API. |
250 | AnyEvent API. |
237 | |
251 | |
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252 | AnyEvent has two additional methods that return the "current time": |
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253 | |
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254 | =over 4 |
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255 | |
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256 | =item AnyEvent->time |
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257 | |
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258 | This returns the "current wallclock time" as a fractional number of |
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259 | seconds since the Epoch (the same thing as C<time> or C<Time::HiRes::time> |
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260 | return, and the result is guaranteed to be compatible with those). |
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261 | |
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262 | It progresses independently of any event loop processing, i.e. each call |
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263 | will check the system clock, which usually gets updated frequently. |
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264 | |
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265 | =item AnyEvent->now |
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266 | |
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267 | This also returns the "current wallclock time", but unlike C<time>, above, |
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268 | this value might change only once per event loop iteration, depending on |
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269 | the event loop (most return the same time as C<time>, above). This is the |
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270 | time that AnyEvent's timers get scheduled against. |
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271 | |
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272 | I<In almost all cases (in all cases if you don't care), this is the |
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273 | function to call when you want to know the current time.> |
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274 | |
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275 | This function is also often faster then C<< AnyEvent->time >>, and |
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276 | thus the preferred method if you want some timestamp (for example, |
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277 | L<AnyEvent::Handle> uses this to update it's activity timeouts). |
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278 | |
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279 | The rest of this section is only of relevance if you try to be very exact |
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280 | with your timing, you can skip it without bad conscience. |
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281 | |
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282 | For a practical example of when these times differ, consider L<Event::Lib> |
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283 | and L<EV> and the following set-up: |
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284 | |
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285 | The event loop is running and has just invoked one of your callback at |
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286 | time=500 (assume no other callbacks delay processing). In your callback, |
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287 | you wait a second by executing C<sleep 1> (blocking the process for a |
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288 | second) and then (at time=501) you create a relative timer that fires |
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289 | after three seconds. |
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290 | |
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291 | With L<Event::Lib>, C<< AnyEvent->time >> and C<< AnyEvent->now >> will |
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292 | both return C<501>, because that is the current time, and the timer will |
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293 | be scheduled to fire at time=504 (C<501> + C<3>). |
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294 | |
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295 | With L<EV>, C<< AnyEvent->time >> returns C<501> (as that is the current |
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296 | time), but C<< AnyEvent->now >> returns C<500>, as that is the time the |
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297 | last event processing phase started. With L<EV>, your timer gets scheduled |
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298 | to run at time=503 (C<500> + C<3>). |
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299 | |
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300 | In one sense, L<Event::Lib> is more exact, as it uses the current time |
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301 | regardless of any delays introduced by event processing. However, most |
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302 | callbacks do not expect large delays in processing, so this causes a |
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303 | higher drift (and a lot more system calls to get the current time). |
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304 | |
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305 | In another sense, L<EV> is more exact, as your timer will be scheduled at |
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306 | the same time, regardless of how long event processing actually took. |
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307 | |
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308 | In either case, if you care (and in most cases, you don't), then you |
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309 | can get whatever behaviour you want with any event loop, by taking the |
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310 | difference between C<< AnyEvent->time >> and C<< AnyEvent->now >> into |
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311 | account. |
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312 | |
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313 | =back |
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314 | |
238 | =head2 SIGNAL WATCHERS |
315 | =head2 SIGNAL WATCHERS |
239 | |
316 | |
240 | 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 |
241 | 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 |
242 | be invoked whenever a signal occurs. |
319 | callback to be invoked whenever a signal occurs. |
243 | |
320 | |
244 | Although the callback might get passed parameters, their value and |
321 | Although the callback might get passed parameters, their value and |
245 | presence is undefined and you cannot rely on them. Portable AnyEvent |
322 | presence is undefined and you cannot rely on them. Portable AnyEvent |
246 | callbacks cannot use arguments passed to signal watcher callbacks. |
323 | callbacks cannot use arguments passed to signal watcher callbacks. |
247 | |
324 | |
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263 | =head2 CHILD PROCESS WATCHERS |
340 | =head2 CHILD PROCESS WATCHERS |
264 | |
341 | |
265 | You can also watch on a child process exit and catch its exit status. |
342 | You can also watch on a child process exit and catch its exit status. |
266 | |
343 | |
267 | The child process is specified by the C<pid> argument (if set to C<0>, it |
344 | The child process is specified by the C<pid> argument (if set to C<0>, it |
268 | watches for any child process exit). The watcher will trigger as often |
345 | watches for any child process exit). The watcher will triggered only when |
269 | as status change for the child are received. This works by installing a |
346 | the child process has finished and an exit status is available, not on |
270 | signal handler for C<SIGCHLD>. The callback will be called with the pid |
347 | any trace events (stopped/continued). |
271 | and exit status (as returned by waitpid), so unlike other watcher types, |
348 | |
272 | you I<can> rely on child watcher callback arguments. |
349 | The callback will be called with the pid and exit status (as returned by |
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350 | waitpid), so unlike other watcher types, you I<can> rely on child watcher |
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351 | callback arguments. |
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352 | |
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353 | This watcher type works by installing a signal handler for C<SIGCHLD>, |
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354 | and since it cannot be shared, nothing else should use SIGCHLD or reap |
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355 | random child processes (waiting for specific child processes, e.g. inside |
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356 | C<system>, is just fine). |
273 | |
357 | |
274 | There is a slight catch to child watchers, however: you usually start them |
358 | There is a slight catch to child watchers, however: you usually start them |
275 | I<after> the child process was created, and this means the process could |
359 | I<after> the child process was created, and this means the process could |
276 | have exited already (and no SIGCHLD will be sent anymore). |
360 | have exited already (and no SIGCHLD will be sent anymore). |
277 | |
361 | |
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283 | AnyEvent program, you I<have> to create at least one watcher before you |
367 | AnyEvent program, you I<have> to create at least one watcher before you |
284 | C<fork> the child (alternatively, you can call C<AnyEvent::detect>). |
368 | C<fork> the child (alternatively, you can call C<AnyEvent::detect>). |
285 | |
369 | |
286 | Example: fork a process and wait for it |
370 | Example: fork a process and wait for it |
287 | |
371 | |
288 | my $done = AnyEvent->condvar; |
372 | my $done = AnyEvent->condvar; |
289 | |
373 | |
290 | my $pid = fork or exit 5; |
374 | my $pid = fork or exit 5; |
291 | |
375 | |
292 | my $w = AnyEvent->child ( |
376 | my $w = AnyEvent->child ( |
293 | pid => $pid, |
377 | pid => $pid, |
294 | cb => sub { |
378 | cb => sub { |
295 | my ($pid, $status) = @_; |
379 | my ($pid, $status) = @_; |
296 | warn "pid $pid exited with status $status"; |
380 | warn "pid $pid exited with status $status"; |
297 | $done->send; |
381 | $done->send; |
298 | }, |
382 | }, |
299 | ); |
383 | ); |
300 | |
384 | |
301 | # do something else, then wait for process exit |
385 | # do something else, then wait for process exit |
302 | $done->recv; |
386 | $done->recv; |
303 | |
387 | |
304 | =head2 CONDITION VARIABLES |
388 | =head2 CONDITION VARIABLES |
305 | |
389 | |
306 | If you are familiar with some event loops you will know that all of them |
390 | If you are familiar with some event loops you will know that all of them |
307 | require you to run some blocking "loop", "run" or similar function that |
391 | require you to run some blocking "loop", "run" or similar function that |
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313 | The instrument to do that is called a "condition variable", so called |
397 | The instrument to do that is called a "condition variable", so called |
314 | because they represent a condition that must become true. |
398 | because they represent a condition that must become true. |
315 | |
399 | |
316 | Condition variables can be created by calling the C<< AnyEvent->condvar |
400 | Condition variables can be created by calling the C<< AnyEvent->condvar |
317 | >> method, usually without arguments. The only argument pair allowed is |
401 | >> method, usually without arguments. The only argument pair allowed is |
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402 | |
318 | C<cb>, which specifies a callback to be called when the condition variable |
403 | C<cb>, which specifies a callback to be called when the condition variable |
319 | becomes true. |
404 | becomes true, with the condition variable as the first argument (but not |
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405 | the results). |
320 | |
406 | |
321 | After creation, the condition variable is "false" until it becomes "true" |
407 | After creation, the condition variable is "false" until it becomes "true" |
322 | by calling the C<send> method (or calling the condition variable as if it |
408 | by calling the C<send> method (or calling the condition variable as if it |
323 | were a callback, read about the caveats in the description for the C<< |
409 | were a callback, read about the caveats in the description for the C<< |
324 | ->send >> method). |
410 | ->send >> method). |
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380 | |
466 | |
381 | my $done = AnyEvent->condvar; |
467 | my $done = AnyEvent->condvar; |
382 | my $delay = AnyEvent->timer (after => 5, cb => $done); |
468 | my $delay = AnyEvent->timer (after => 5, cb => $done); |
383 | $done->recv; |
469 | $done->recv; |
384 | |
470 | |
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471 | Example: Imagine an API that returns a condvar and doesn't support |
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472 | callbacks. This is how you make a synchronous call, for example from |
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473 | the main program: |
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474 | |
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475 | use AnyEvent::CouchDB; |
|
|
476 | |
|
|
477 | ... |
|
|
478 | |
|
|
479 | my @info = $couchdb->info->recv; |
|
|
480 | |
|
|
481 | And this is how you would just ste a callback to be called whenever the |
|
|
482 | results are available: |
|
|
483 | |
|
|
484 | $couchdb->info->cb (sub { |
|
|
485 | my @info = $_[0]->recv; |
|
|
486 | }); |
|
|
487 | |
385 | =head3 METHODS FOR PRODUCERS |
488 | =head3 METHODS FOR PRODUCERS |
386 | |
489 | |
387 | These methods should only be used by the producing side, i.e. the |
490 | These methods should only be used by the producing side, i.e. the |
388 | code/module that eventually sends the signal. Note that it is also |
491 | code/module that eventually sends the signal. Note that it is also |
389 | the producer side which creates the condvar in most cases, but it isn't |
492 | the producer side which creates the condvar in most cases, but it isn't |
… | |
… | |
522 | =item $bool = $cv->ready |
625 | =item $bool = $cv->ready |
523 | |
626 | |
524 | Returns true when the condition is "true", i.e. whether C<send> or |
627 | Returns true when the condition is "true", i.e. whether C<send> or |
525 | C<croak> have been called. |
628 | C<croak> have been called. |
526 | |
629 | |
527 | =item $cb = $cv->cb ([new callback]) |
630 | =item $cb = $cv->cb ($cb->($cv)) |
528 | |
631 | |
529 | This is a mutator function that returns the callback set and optionally |
632 | This is a mutator function that returns the callback set and optionally |
530 | replaces it before doing so. |
633 | replaces it before doing so. |
531 | |
634 | |
532 | The callback will be called when the condition becomes "true", i.e. when |
635 | The callback will be called when the condition becomes "true", i.e. when |
533 | C<send> or C<croak> are called. Calling C<recv> inside the callback |
636 | C<send> or C<croak> are called, with the only argument being the condition |
534 | or at any later time is guaranteed not to block. |
637 | variable itself. Calling C<recv> inside the callback or at any later time |
|
|
638 | is guaranteed not to block. |
535 | |
639 | |
536 | =back |
640 | =back |
537 | |
641 | |
538 | =head1 GLOBAL VARIABLES AND FUNCTIONS |
642 | =head1 GLOBAL VARIABLES AND FUNCTIONS |
539 | |
643 | |
… | |
… | |
668 | =item L<AnyEvent::Util> |
772 | =item L<AnyEvent::Util> |
669 | |
773 | |
670 | Contains various utility functions that replace often-used but blocking |
774 | Contains various utility functions that replace often-used but blocking |
671 | functions such as C<inet_aton> by event-/callback-based versions. |
775 | functions such as C<inet_aton> by event-/callback-based versions. |
672 | |
776 | |
673 | =item L<AnyEvent::Handle> |
|
|
674 | |
|
|
675 | Provide read and write buffers and manages watchers for reads and writes. |
|
|
676 | |
|
|
677 | =item L<AnyEvent::Socket> |
777 | =item L<AnyEvent::Socket> |
678 | |
778 | |
679 | Provides various utility functions for (internet protocol) sockets, |
779 | Provides various utility functions for (internet protocol) sockets, |
680 | addresses and name resolution. Also functions to create non-blocking tcp |
780 | addresses and name resolution. Also functions to create non-blocking tcp |
681 | connections or tcp servers, with IPv6 and SRV record support and more. |
781 | connections or tcp servers, with IPv6 and SRV record support and more. |
682 | |
782 | |
|
|
783 | =item L<AnyEvent::Handle> |
|
|
784 | |
|
|
785 | Provide read and write buffers, manages watchers for reads and writes, |
|
|
786 | supports raw and formatted I/O, I/O queued and fully transparent and |
|
|
787 | non-blocking SSL/TLS. |
|
|
788 | |
683 | =item L<AnyEvent::DNS> |
789 | =item L<AnyEvent::DNS> |
684 | |
790 | |
685 | Provides rich asynchronous DNS resolver capabilities. |
791 | Provides rich asynchronous DNS resolver capabilities. |
686 | |
792 | |
|
|
793 | =item L<AnyEvent::HTTP> |
|
|
794 | |
|
|
795 | A simple-to-use HTTP library that is capable of making a lot of concurrent |
|
|
796 | HTTP requests. |
|
|
797 | |
687 | =item L<AnyEvent::HTTPD> |
798 | =item L<AnyEvent::HTTPD> |
688 | |
799 | |
689 | Provides a simple web application server framework. |
800 | Provides a simple web application server framework. |
690 | |
801 | |
691 | =item L<AnyEvent::FastPing> |
802 | =item L<AnyEvent::FastPing> |
692 | |
803 | |
693 | The fastest ping in the west. |
804 | The fastest ping in the west. |
694 | |
805 | |
|
|
806 | =item L<AnyEvent::DBI> |
|
|
807 | |
|
|
808 | Executes L<DBI> requests asynchronously in a proxy process. |
|
|
809 | |
|
|
810 | =item L<AnyEvent::AIO> |
|
|
811 | |
|
|
812 | Truly asynchronous I/O, should be in the toolbox of every event |
|
|
813 | programmer. AnyEvent::AIO transparently fuses L<IO::AIO> and AnyEvent |
|
|
814 | together. |
|
|
815 | |
|
|
816 | =item L<AnyEvent::BDB> |
|
|
817 | |
|
|
818 | Truly asynchronous Berkeley DB access. AnyEvent::BDB transparently fuses |
|
|
819 | L<BDB> and AnyEvent together. |
|
|
820 | |
|
|
821 | =item L<AnyEvent::GPSD> |
|
|
822 | |
|
|
823 | A non-blocking interface to gpsd, a daemon delivering GPS information. |
|
|
824 | |
|
|
825 | =item L<AnyEvent::IGS> |
|
|
826 | |
|
|
827 | A non-blocking interface to the Internet Go Server protocol (used by |
|
|
828 | L<App::IGS>). |
|
|
829 | |
695 | =item L<Net::IRC3> |
830 | =item L<AnyEvent::IRC> |
696 | |
831 | |
697 | AnyEvent based IRC client module family. |
832 | AnyEvent based IRC client module family (replacing the older Net::IRC3). |
698 | |
833 | |
699 | =item L<Net::XMPP2> |
834 | =item L<Net::XMPP2> |
700 | |
835 | |
701 | AnyEvent based XMPP (Jabber protocol) module family. |
836 | AnyEvent based XMPP (Jabber protocol) module family. |
702 | |
837 | |
… | |
… | |
711 | |
846 | |
712 | =item L<Coro> |
847 | =item L<Coro> |
713 | |
848 | |
714 | Has special support for AnyEvent via L<Coro::AnyEvent>. |
849 | Has special support for AnyEvent via L<Coro::AnyEvent>. |
715 | |
850 | |
716 | =item L<AnyEvent::AIO>, L<IO::AIO> |
|
|
717 | |
|
|
718 | Truly asynchronous I/O, should be in the toolbox of every event |
|
|
719 | programmer. AnyEvent::AIO transparently fuses IO::AIO and AnyEvent |
|
|
720 | together. |
|
|
721 | |
|
|
722 | =item L<AnyEvent::BDB>, L<BDB> |
|
|
723 | |
|
|
724 | Truly asynchronous Berkeley DB access. AnyEvent::AIO transparently fuses |
|
|
725 | IO::AIO and AnyEvent together. |
|
|
726 | |
|
|
727 | =item L<IO::Lambda> |
851 | =item L<IO::Lambda> |
728 | |
852 | |
729 | The lambda approach to I/O - don't ask, look there. Can use AnyEvent. |
853 | The lambda approach to I/O - don't ask, look there. Can use AnyEvent. |
730 | |
854 | |
731 | =back |
855 | =back |
… | |
… | |
733 | =cut |
857 | =cut |
734 | |
858 | |
735 | package AnyEvent; |
859 | package AnyEvent; |
736 | |
860 | |
737 | no warnings; |
861 | no warnings; |
738 | use strict; |
862 | use strict qw(vars subs); |
739 | |
863 | |
740 | use Carp; |
864 | use Carp; |
741 | |
865 | |
742 | our $VERSION = '4.05'; |
866 | our $VERSION = 4.34; |
743 | our $MODEL; |
867 | our $MODEL; |
744 | |
868 | |
745 | our $AUTOLOAD; |
869 | our $AUTOLOAD; |
746 | our @ISA; |
870 | our @ISA; |
747 | |
871 | |
… | |
… | |
779 | [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza |
903 | [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza |
780 | [Wx:: => AnyEvent::Impl::POE::], |
904 | [Wx:: => AnyEvent::Impl::POE::], |
781 | [Prima:: => AnyEvent::Impl::POE::], |
905 | [Prima:: => AnyEvent::Impl::POE::], |
782 | ); |
906 | ); |
783 | |
907 | |
784 | our %method = map +($_ => 1), qw(io timer signal child condvar one_event DESTROY); |
908 | our %method = map +($_ => 1), qw(io timer time now signal child condvar one_event DESTROY); |
785 | |
909 | |
786 | our @post_detect; |
910 | our @post_detect; |
787 | |
911 | |
788 | sub post_detect(&) { |
912 | sub post_detect(&) { |
789 | my ($cb) = @_; |
913 | my ($cb) = @_; |
… | |
… | |
850 | $MODEL |
974 | $MODEL |
851 | or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib."; |
975 | or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib."; |
852 | } |
976 | } |
853 | } |
977 | } |
854 | |
978 | |
|
|
979 | push @{"$MODEL\::ISA"}, "AnyEvent::Base"; |
|
|
980 | |
855 | unshift @ISA, $MODEL; |
981 | unshift @ISA, $MODEL; |
856 | push @{"$MODEL\::ISA"}, "AnyEvent::Base"; |
982 | |
|
|
983 | require AnyEvent::Strict if $ENV{PERL_ANYEVENT_STRICT}; |
857 | |
984 | |
858 | (shift @post_detect)->() while @post_detect; |
985 | (shift @post_detect)->() while @post_detect; |
859 | } |
986 | } |
860 | |
987 | |
861 | $MODEL |
988 | $MODEL |
… | |
… | |
871 | |
998 | |
872 | my $class = shift; |
999 | my $class = shift; |
873 | $class->$func (@_); |
1000 | $class->$func (@_); |
874 | } |
1001 | } |
875 | |
1002 | |
|
|
1003 | # utility function to dup a filehandle. this is used by many backends |
|
|
1004 | # to support binding more than one watcher per filehandle (they usually |
|
|
1005 | # allow only one watcher per fd, so we dup it to get a different one). |
|
|
1006 | sub _dupfh($$$$) { |
|
|
1007 | my ($poll, $fh, $r, $w) = @_; |
|
|
1008 | |
|
|
1009 | require Fcntl; |
|
|
1010 | |
|
|
1011 | # cygwin requires the fh mode to be matching, unix doesn't |
|
|
1012 | my ($rw, $mode) = $poll eq "r" ? ($r, "<") |
|
|
1013 | : $poll eq "w" ? ($w, ">") |
|
|
1014 | : Carp::croak "AnyEvent->io requires poll set to either 'r' or 'w'"; |
|
|
1015 | |
|
|
1016 | open my $fh2, "$mode&" . fileno $fh |
|
|
1017 | or die "cannot dup() filehandle: $!"; |
|
|
1018 | |
|
|
1019 | # we assume CLOEXEC is already set by perl in all important cases |
|
|
1020 | |
|
|
1021 | ($fh2, $rw) |
|
|
1022 | } |
|
|
1023 | |
876 | package AnyEvent::Base; |
1024 | package AnyEvent::Base; |
|
|
1025 | |
|
|
1026 | # default implementation for now and time |
|
|
1027 | |
|
|
1028 | BEGIN { |
|
|
1029 | if (eval "use Time::HiRes (); time (); 1") { |
|
|
1030 | *_time = \&Time::HiRes::time; |
|
|
1031 | # if (eval "use POSIX (); (POSIX::times())... |
|
|
1032 | } else { |
|
|
1033 | *_time = sub { time }; # epic fail |
|
|
1034 | } |
|
|
1035 | } |
|
|
1036 | |
|
|
1037 | sub time { _time } |
|
|
1038 | sub now { _time } |
877 | |
1039 | |
878 | # default implementation for ->condvar |
1040 | # default implementation for ->condvar |
879 | |
1041 | |
880 | sub condvar { |
1042 | sub condvar { |
881 | bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, AnyEvent::CondVar:: |
1043 | bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, AnyEvent::CondVar:: |
… | |
… | |
902 | sub AnyEvent::Base::Signal::DESTROY { |
1064 | sub AnyEvent::Base::Signal::DESTROY { |
903 | my ($signal, $cb) = @{$_[0]}; |
1065 | my ($signal, $cb) = @{$_[0]}; |
904 | |
1066 | |
905 | delete $SIG_CB{$signal}{$cb}; |
1067 | delete $SIG_CB{$signal}{$cb}; |
906 | |
1068 | |
907 | $SIG{$signal} = 'DEFAULT' unless keys %{ $SIG_CB{$signal} }; |
1069 | delete $SIG{$signal} unless keys %{ $SIG_CB{$signal} }; |
908 | } |
1070 | } |
909 | |
1071 | |
910 | # default implementation for ->child |
1072 | # default implementation for ->child |
911 | |
1073 | |
912 | our %PID_CB; |
1074 | our %PID_CB; |
… | |
… | |
1020 | |
1182 | |
1021 | # undocumented/compatibility with pre-3.4 |
1183 | # undocumented/compatibility with pre-3.4 |
1022 | *broadcast = \&send; |
1184 | *broadcast = \&send; |
1023 | *wait = \&_wait; |
1185 | *wait = \&_wait; |
1024 | |
1186 | |
|
|
1187 | =head1 ERROR AND EXCEPTION HANDLING |
|
|
1188 | |
|
|
1189 | In general, AnyEvent does not do any error handling - it relies on the |
|
|
1190 | caller to do that if required. The L<AnyEvent::Strict> module (see also |
|
|
1191 | the C<PERL_ANYEVENT_STRICT> environment variable, below) provides strict |
|
|
1192 | checking of all AnyEvent methods, however, which is highly useful during |
|
|
1193 | development. |
|
|
1194 | |
|
|
1195 | As for exception handling (i.e. runtime errors and exceptions thrown while |
|
|
1196 | executing a callback), this is not only highly event-loop specific, but |
|
|
1197 | also not in any way wrapped by this module, as this is the job of the main |
|
|
1198 | program. |
|
|
1199 | |
|
|
1200 | The pure perl event loop simply re-throws the exception (usually |
|
|
1201 | within C<< condvar->recv >>), the L<Event> and L<EV> modules call C<< |
|
|
1202 | $Event/EV::DIED->() >>, L<Glib> uses C<< install_exception_handler >> and |
|
|
1203 | so on. |
|
|
1204 | |
|
|
1205 | =head1 ENVIRONMENT VARIABLES |
|
|
1206 | |
|
|
1207 | The following environment variables are used by this module or its |
|
|
1208 | submodules: |
|
|
1209 | |
|
|
1210 | =over 4 |
|
|
1211 | |
|
|
1212 | =item C<PERL_ANYEVENT_VERBOSE> |
|
|
1213 | |
|
|
1214 | By default, AnyEvent will be completely silent except in fatal |
|
|
1215 | conditions. You can set this environment variable to make AnyEvent more |
|
|
1216 | talkative. |
|
|
1217 | |
|
|
1218 | When set to C<1> or higher, causes AnyEvent to warn about unexpected |
|
|
1219 | conditions, such as not being able to load the event model specified by |
|
|
1220 | C<PERL_ANYEVENT_MODEL>. |
|
|
1221 | |
|
|
1222 | When set to C<2> or higher, cause AnyEvent to report to STDERR which event |
|
|
1223 | model it chooses. |
|
|
1224 | |
|
|
1225 | =item C<PERL_ANYEVENT_STRICT> |
|
|
1226 | |
|
|
1227 | AnyEvent does not do much argument checking by default, as thorough |
|
|
1228 | argument checking is very costly. Setting this variable to a true value |
|
|
1229 | will cause AnyEvent to load C<AnyEvent::Strict> and then to thoroughly |
|
|
1230 | check the arguments passed to most method calls. If it finds any problems |
|
|
1231 | it will croak. |
|
|
1232 | |
|
|
1233 | In other words, enables "strict" mode. |
|
|
1234 | |
|
|
1235 | Unlike C<use strict>, it is definitely recommended ot keep it off in |
|
|
1236 | production. Keeping C<PERL_ANYEVENT_STRICT=1> in your environment while |
|
|
1237 | developing programs can be very useful, however. |
|
|
1238 | |
|
|
1239 | =item C<PERL_ANYEVENT_MODEL> |
|
|
1240 | |
|
|
1241 | This can be used to specify the event model to be used by AnyEvent, before |
|
|
1242 | auto detection and -probing kicks in. It must be a string consisting |
|
|
1243 | entirely of ASCII letters. The string C<AnyEvent::Impl::> gets prepended |
|
|
1244 | and the resulting module name is loaded and if the load was successful, |
|
|
1245 | used as event model. If it fails to load AnyEvent will proceed with |
|
|
1246 | auto detection and -probing. |
|
|
1247 | |
|
|
1248 | This functionality might change in future versions. |
|
|
1249 | |
|
|
1250 | For example, to force the pure perl model (L<AnyEvent::Impl::Perl>) you |
|
|
1251 | could start your program like this: |
|
|
1252 | |
|
|
1253 | PERL_ANYEVENT_MODEL=Perl perl ... |
|
|
1254 | |
|
|
1255 | =item C<PERL_ANYEVENT_PROTOCOLS> |
|
|
1256 | |
|
|
1257 | Used by both L<AnyEvent::DNS> and L<AnyEvent::Socket> to determine preferences |
|
|
1258 | for IPv4 or IPv6. The default is unspecified (and might change, or be the result |
|
|
1259 | of auto probing). |
|
|
1260 | |
|
|
1261 | Must be set to a comma-separated list of protocols or address families, |
|
|
1262 | current supported: C<ipv4> and C<ipv6>. Only protocols mentioned will be |
|
|
1263 | used, and preference will be given to protocols mentioned earlier in the |
|
|
1264 | list. |
|
|
1265 | |
|
|
1266 | This variable can effectively be used for denial-of-service attacks |
|
|
1267 | against local programs (e.g. when setuid), although the impact is likely |
|
|
1268 | small, as the program has to handle connection errors already- |
|
|
1269 | |
|
|
1270 | Examples: C<PERL_ANYEVENT_PROTOCOLS=ipv4,ipv6> - prefer IPv4 over IPv6, |
|
|
1271 | but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4> |
|
|
1272 | - only support IPv4, never try to resolve or contact IPv6 |
|
|
1273 | addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or |
|
|
1274 | IPv6, but prefer IPv6 over IPv4. |
|
|
1275 | |
|
|
1276 | =item C<PERL_ANYEVENT_EDNS0> |
|
|
1277 | |
|
|
1278 | Used by L<AnyEvent::DNS> to decide whether to use the EDNS0 extension |
|
|
1279 | for DNS. This extension is generally useful to reduce DNS traffic, but |
|
|
1280 | some (broken) firewalls drop such DNS packets, which is why it is off by |
|
|
1281 | default. |
|
|
1282 | |
|
|
1283 | Setting this variable to C<1> will cause L<AnyEvent::DNS> to announce |
|
|
1284 | EDNS0 in its DNS requests. |
|
|
1285 | |
|
|
1286 | =item C<PERL_ANYEVENT_MAX_FORKS> |
|
|
1287 | |
|
|
1288 | The maximum number of child processes that C<AnyEvent::Util::fork_call> |
|
|
1289 | will create in parallel. |
|
|
1290 | |
|
|
1291 | =back |
|
|
1292 | |
1025 | =head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE |
1293 | =head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE |
1026 | |
1294 | |
1027 | This is an advanced topic that you do not normally need to use AnyEvent in |
1295 | This is an advanced topic that you do not normally need to use AnyEvent in |
1028 | a module. This section is only of use to event loop authors who want to |
1296 | a module. This section is only of use to event loop authors who want to |
1029 | provide AnyEvent compatibility. |
1297 | provide AnyEvent compatibility. |
… | |
… | |
1062 | |
1330 | |
1063 | I<rxvt-unicode> also cheats a bit by not providing blocking access to |
1331 | I<rxvt-unicode> also cheats a bit by not providing blocking access to |
1064 | condition variables: code blocking while waiting for a condition will |
1332 | condition variables: code blocking while waiting for a condition will |
1065 | C<die>. This still works with most modules/usages, and blocking calls must |
1333 | C<die>. This still works with most modules/usages, and blocking calls must |
1066 | not be done in an interactive application, so it makes sense. |
1334 | not be done in an interactive application, so it makes sense. |
1067 | |
|
|
1068 | =head1 ENVIRONMENT VARIABLES |
|
|
1069 | |
|
|
1070 | The following environment variables are used by this module: |
|
|
1071 | |
|
|
1072 | =over 4 |
|
|
1073 | |
|
|
1074 | =item C<PERL_ANYEVENT_VERBOSE> |
|
|
1075 | |
|
|
1076 | By default, AnyEvent will be completely silent except in fatal |
|
|
1077 | conditions. You can set this environment variable to make AnyEvent more |
|
|
1078 | talkative. |
|
|
1079 | |
|
|
1080 | When set to C<1> or higher, causes AnyEvent to warn about unexpected |
|
|
1081 | conditions, such as not being able to load the event model specified by |
|
|
1082 | C<PERL_ANYEVENT_MODEL>. |
|
|
1083 | |
|
|
1084 | When set to C<2> or higher, cause AnyEvent to report to STDERR which event |
|
|
1085 | model it chooses. |
|
|
1086 | |
|
|
1087 | =item C<PERL_ANYEVENT_MODEL> |
|
|
1088 | |
|
|
1089 | This can be used to specify the event model to be used by AnyEvent, before |
|
|
1090 | auto detection and -probing kicks in. It must be a string consisting |
|
|
1091 | entirely of ASCII letters. The string C<AnyEvent::Impl::> gets prepended |
|
|
1092 | and the resulting module name is loaded and if the load was successful, |
|
|
1093 | used as event model. If it fails to load AnyEvent will proceed with |
|
|
1094 | auto detection and -probing. |
|
|
1095 | |
|
|
1096 | This functionality might change in future versions. |
|
|
1097 | |
|
|
1098 | For example, to force the pure perl model (L<AnyEvent::Impl::Perl>) you |
|
|
1099 | could start your program like this: |
|
|
1100 | |
|
|
1101 | PERL_ANYEVENT_MODEL=Perl perl ... |
|
|
1102 | |
|
|
1103 | =item C<PERL_ANYEVENT_PROTOCOLS> |
|
|
1104 | |
|
|
1105 | Used by both L<AnyEvent::DNS> and L<AnyEvent::Socket> to determine preferences |
|
|
1106 | for IPv4 or IPv6. The default is unspecified (and might change, or be the result |
|
|
1107 | of auto probing). |
|
|
1108 | |
|
|
1109 | Must be set to a comma-separated list of protocols or address families, |
|
|
1110 | current supported: C<ipv4> and C<ipv6>. Only protocols mentioned will be |
|
|
1111 | used, and preference will be given to protocols mentioned earlier in the |
|
|
1112 | list. |
|
|
1113 | |
|
|
1114 | This variable can effectively be used for denial-of-service attacks |
|
|
1115 | against local programs (e.g. when setuid), although the impact is likely |
|
|
1116 | small, as the program has to handle connection errors already- |
|
|
1117 | |
|
|
1118 | Examples: C<PERL_ANYEVENT_PROTOCOLS=ipv4,ipv6> - prefer IPv4 over IPv6, |
|
|
1119 | but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4> |
|
|
1120 | - only support IPv4, never try to resolve or contact IPv6 |
|
|
1121 | addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or |
|
|
1122 | IPv6, but prefer IPv6 over IPv4. |
|
|
1123 | |
|
|
1124 | =item C<PERL_ANYEVENT_EDNS0> |
|
|
1125 | |
|
|
1126 | Used by L<AnyEvent::DNS> to decide whether to use the EDNS0 extension |
|
|
1127 | for DNS. This extension is generally useful to reduce DNS traffic, but |
|
|
1128 | some (broken) firewalls drop such DNS packets, which is why it is off by |
|
|
1129 | default. |
|
|
1130 | |
|
|
1131 | Setting this variable to C<1> will cause L<AnyEvent::DNS> to announce |
|
|
1132 | EDNS0 in its DNS requests. |
|
|
1133 | |
|
|
1134 | =item C<PERL_ANYEVENT_MAX_FORKS> |
|
|
1135 | |
|
|
1136 | The maximum number of child processes that C<AnyEvent::Util::fork_call> |
|
|
1137 | will create in parallel. |
|
|
1138 | |
|
|
1139 | =back |
|
|
1140 | |
1335 | |
1141 | =head1 EXAMPLE PROGRAM |
1336 | =head1 EXAMPLE PROGRAM |
1142 | |
1337 | |
1143 | The following program uses an I/O watcher to read data from STDIN, a timer |
1338 | The following program uses an I/O watcher to read data from STDIN, a timer |
1144 | to display a message once per second, and a condition variable to quit the |
1339 | to display a message once per second, and a condition variable to quit the |
… | |
… | |
1338 | watcher. |
1533 | watcher. |
1339 | |
1534 | |
1340 | =head3 Results |
1535 | =head3 Results |
1341 | |
1536 | |
1342 | name watchers bytes create invoke destroy comment |
1537 | name watchers bytes create invoke destroy comment |
1343 | EV/EV 400000 244 0.56 0.46 0.31 EV native interface |
1538 | EV/EV 400000 224 0.47 0.35 0.27 EV native interface |
1344 | EV/Any 100000 244 2.50 0.46 0.29 EV + AnyEvent watchers |
1539 | EV/Any 100000 224 2.88 0.34 0.27 EV + AnyEvent watchers |
1345 | CoroEV/Any 100000 244 2.49 0.44 0.29 coroutines + Coro::Signal |
1540 | CoroEV/Any 100000 224 2.85 0.35 0.28 coroutines + Coro::Signal |
1346 | Perl/Any 100000 513 4.92 0.87 1.12 pure perl implementation |
1541 | Perl/Any 100000 452 4.13 0.73 0.95 pure perl implementation |
1347 | Event/Event 16000 516 31.88 31.30 0.85 Event native interface |
1542 | Event/Event 16000 517 32.20 31.80 0.81 Event native interface |
1348 | Event/Any 16000 590 35.75 31.42 1.08 Event + AnyEvent watchers |
1543 | Event/Any 16000 590 35.85 31.55 1.06 Event + AnyEvent watchers |
1349 | Glib/Any 16000 1357 98.22 12.41 54.00 quadratic behaviour |
1544 | Glib/Any 16000 1357 102.33 12.31 51.00 quadratic behaviour |
1350 | Tk/Any 2000 1860 26.97 67.98 14.00 SEGV with >> 2000 watchers |
1545 | Tk/Any 2000 1860 27.20 66.31 14.00 SEGV with >> 2000 watchers |
1351 | POE/Event 2000 6644 108.64 736.02 14.73 via POE::Loop::Event |
1546 | POE/Event 2000 6328 109.99 751.67 14.02 via POE::Loop::Event |
1352 | POE/Select 2000 6343 94.13 809.12 565.96 via POE::Loop::Select |
1547 | POE/Select 2000 6027 94.54 809.13 579.80 via POE::Loop::Select |
1353 | |
1548 | |
1354 | =head3 Discussion |
1549 | =head3 Discussion |
1355 | |
1550 | |
1356 | The benchmark does I<not> measure scalability of the event loop very |
1551 | The benchmark does I<not> measure scalability of the event loop very |
1357 | well. For example, a select-based event loop (such as the pure perl one) |
1552 | well. For example, a select-based event loop (such as the pure perl one) |
… | |
… | |
1559 | watchers, as the management overhead dominates. |
1754 | watchers, as the management overhead dominates. |
1560 | |
1755 | |
1561 | =back |
1756 | =back |
1562 | |
1757 | |
1563 | |
1758 | |
|
|
1759 | =head1 SIGNALS |
|
|
1760 | |
|
|
1761 | AnyEvent currently installs handlers for these signals: |
|
|
1762 | |
|
|
1763 | =over 4 |
|
|
1764 | |
|
|
1765 | =item SIGCHLD |
|
|
1766 | |
|
|
1767 | A handler for C<SIGCHLD> is installed by AnyEvent's child watcher |
|
|
1768 | emulation for event loops that do not support them natively. Also, some |
|
|
1769 | event loops install a similar handler. |
|
|
1770 | |
|
|
1771 | =item SIGPIPE |
|
|
1772 | |
|
|
1773 | A no-op handler is installed for C<SIGPIPE> when C<$SIG{PIPE}> is C<undef> |
|
|
1774 | when AnyEvent gets loaded. |
|
|
1775 | |
|
|
1776 | The rationale for this is that AnyEvent users usually do not really depend |
|
|
1777 | on SIGPIPE delivery (which is purely an optimisation for shell use, or |
|
|
1778 | badly-written programs), but C<SIGPIPE> can cause spurious and rare |
|
|
1779 | program exits as a lot of people do not expect C<SIGPIPE> when writing to |
|
|
1780 | some random socket. |
|
|
1781 | |
|
|
1782 | The rationale for installing a no-op handler as opposed to ignoring it is |
|
|
1783 | that this way, the handler will be restored to defaults on exec. |
|
|
1784 | |
|
|
1785 | Feel free to install your own handler, or reset it to defaults. |
|
|
1786 | |
|
|
1787 | =back |
|
|
1788 | |
|
|
1789 | =cut |
|
|
1790 | |
|
|
1791 | $SIG{PIPE} = sub { } |
|
|
1792 | unless defined $SIG{PIPE}; |
|
|
1793 | |
|
|
1794 | |
1564 | =head1 FORK |
1795 | =head1 FORK |
1565 | |
1796 | |
1566 | Most event libraries are not fork-safe. The ones who are usually are |
1797 | Most event libraries are not fork-safe. The ones who are usually are |
1567 | because they rely on inefficient but fork-safe C<select> or C<poll> |
1798 | because they rely on inefficient but fork-safe C<select> or C<poll> |
1568 | calls. Only L<EV> is fully fork-aware. |
1799 | calls. Only L<EV> is fully fork-aware. |
… | |
… | |
1581 | specified in the variable. |
1812 | specified in the variable. |
1582 | |
1813 | |
1583 | You can make AnyEvent completely ignore this variable by deleting it |
1814 | You can make AnyEvent completely ignore this variable by deleting it |
1584 | before the first watcher gets created, e.g. with a C<BEGIN> block: |
1815 | before the first watcher gets created, e.g. with a C<BEGIN> block: |
1585 | |
1816 | |
1586 | BEGIN { delete $ENV{PERL_ANYEVENT_MODEL} } |
1817 | BEGIN { delete $ENV{PERL_ANYEVENT_MODEL} } |
1587 | |
1818 | |
1588 | use AnyEvent; |
1819 | use AnyEvent; |
1589 | |
1820 | |
1590 | Similar considerations apply to $ENV{PERL_ANYEVENT_VERBOSE}, as that can |
1821 | Similar considerations apply to $ENV{PERL_ANYEVENT_VERBOSE}, as that can |
1591 | be used to probe what backend is used and gain other information (which is |
1822 | be used to probe what backend is used and gain other information (which is |
1592 | probably even less useful to an attacker than PERL_ANYEVENT_MODEL). |
1823 | probably even less useful to an attacker than PERL_ANYEVENT_MODEL), and |
|
|
1824 | $ENV{PERL_ANYEGENT_STRICT}. |
|
|
1825 | |
|
|
1826 | |
|
|
1827 | =head1 BUGS |
|
|
1828 | |
|
|
1829 | Perl 5.8 has numerous memleaks that sometimes hit this module and are hard |
|
|
1830 | to work around. If you suffer from memleaks, first upgrade to Perl 5.10 |
|
|
1831 | and check wether the leaks still show up. (Perl 5.10.0 has other annoying |
|
|
1832 | mamleaks, such as leaking on C<map> and C<grep> but it is usually not as |
|
|
1833 | pronounced). |
1593 | |
1834 | |
1594 | |
1835 | |
1595 | =head1 SEE ALSO |
1836 | =head1 SEE ALSO |
1596 | |
1837 | |
1597 | Utility functions: L<AnyEvent::Util>. |
1838 | Utility functions: L<AnyEvent::Util>. |
… | |
… | |
1614 | Nontrivial usage examples: L<Net::FCP>, L<Net::XMPP2>, L<AnyEvent::DNS>. |
1855 | Nontrivial usage examples: L<Net::FCP>, L<Net::XMPP2>, L<AnyEvent::DNS>. |
1615 | |
1856 | |
1616 | |
1857 | |
1617 | =head1 AUTHOR |
1858 | =head1 AUTHOR |
1618 | |
1859 | |
1619 | Marc Lehmann <schmorp@schmorp.de> |
1860 | Marc Lehmann <schmorp@schmorp.de> |
1620 | http://home.schmorp.de/ |
1861 | http://home.schmorp.de/ |
1621 | |
1862 | |
1622 | =cut |
1863 | =cut |
1623 | |
1864 | |
1624 | 1 |
1865 | 1 |
1625 | |
1866 | |