| … | |
… | |
| 2 | EV - perl interface to libev, a high performance full-featured event |
2 | EV - perl interface to libev, a high performance full-featured event |
| 3 | loop |
3 | loop |
| 4 | |
4 | |
| 5 | SYNOPSIS |
5 | SYNOPSIS |
| 6 | use EV; |
6 | use EV; |
| 7 | |
7 | |
| 8 | # TIMERS |
8 | # TIMERS |
| 9 | |
9 | |
| 10 | my $w = EV::timer 2, 0, sub { |
10 | my $w = EV::timer 2, 0, sub { |
| 11 | warn "is called after 2s"; |
11 | warn "is called after 2s"; |
| 12 | }; |
12 | }; |
| 13 | |
13 | |
| 14 | my $w = EV::timer 2, 2, sub { |
14 | my $w = EV::timer 2, 2, sub { |
| 15 | warn "is called roughly every 2s (repeat = 2)"; |
15 | warn "is called roughly every 2s (repeat = 2)"; |
| 16 | }; |
16 | }; |
| 17 | |
17 | |
| 18 | undef $w; # destroy event watcher again |
18 | undef $w; # destroy event watcher again |
| 19 | |
19 | |
| 20 | my $w = EV::periodic 0, 60, 0, sub { |
20 | my $w = EV::periodic 0, 60, 0, sub { |
| 21 | warn "is called every minute, on the minute, exactly"; |
21 | warn "is called every minute, on the minute, exactly"; |
| 22 | }; |
22 | }; |
|
|
23 | |
| 23 | |
24 | # IO |
| 24 | # IO |
25 | |
| 25 | |
|
|
| 26 | my $w = EV::io *STDIN, EV::READ, sub { |
26 | my $w = EV::io *STDIN, EV::READ, sub { |
| 27 | my ($w, $revents) = @_; # all callbacks receive the watcher and event mask |
27 | my ($w, $revents) = @_; # all callbacks receive the watcher and event mask |
| 28 | warn "stdin is readable, you entered: ", <STDIN>; |
28 | warn "stdin is readable, you entered: ", <STDIN>; |
| 29 | }; |
29 | }; |
| 30 | |
30 | |
| 31 | # SIGNALS |
31 | # SIGNALS |
| 32 | |
32 | |
| 33 | my $w = EV::signal 'QUIT', sub { |
33 | my $w = EV::signal 'QUIT', sub { |
| 34 | warn "sigquit received\n"; |
34 | warn "sigquit received\n"; |
| 35 | }; |
35 | }; |
| 36 | |
36 | |
| 37 | # CHILD/PID STATUS CHANGES |
37 | # CHILD/PID STATUS CHANGES |
| 38 | |
38 | |
| 39 | my $w = EV::child 666, 0, sub { |
39 | my $w = EV::child 666, 0, sub { |
| 40 | my ($w, $revents) = @_; |
40 | my ($w, $revents) = @_; |
| 41 | my $status = $w->rstatus; |
41 | my $status = $w->rstatus; |
| 42 | }; |
42 | }; |
| 43 | |
43 | |
| 44 | # STAT CHANGES |
44 | # STAT CHANGES |
| 45 | my $w = EV::stat "/etc/passwd", 10, sub { |
45 | my $w = EV::stat "/etc/passwd", 10, sub { |
| 46 | my ($w, $revents) = @_; |
46 | my ($w, $revents) = @_; |
| 47 | warn $w->path, " has changed somehow.\n"; |
47 | warn $w->path, " has changed somehow.\n"; |
| 48 | }; |
48 | }; |
| 49 | |
49 | |
| 50 | # MAINLOOP |
50 | # MAINLOOP |
| 51 | EV::loop; # loop until EV::unloop is called or all watchers stop |
51 | EV::run; # loop until EV::unloop is called or all watchers stop |
| 52 | EV::loop EV::LOOP_ONESHOT; # block until at least one event could be handled |
52 | EV::run EV::RUN_ONCE; # block until at least one event could be handled |
| 53 | EV::loop EV::LOOP_NONBLOCK; # try to handle same events, but do not block |
53 | EV::run EV::RUN_NOWAIT; # try to handle same events, but do not block |
|
|
54 | |
|
|
55 | BEFORE YOU START USING THIS MODULE |
|
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56 | If you only need timer, I/O, signal, child and idle watchers and not the |
|
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57 | advanced functionality of this module, consider using AnyEvent instead, |
|
|
58 | specifically the simplified API described in AE. |
|
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59 | |
|
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60 | When used with EV as backend, the AE API is as fast as the native EV |
|
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61 | API, but your programs/modules will still run with many other event |
|
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62 | loops. |
| 54 | |
63 | |
| 55 | DESCRIPTION |
64 | DESCRIPTION |
| 56 | This module provides an interface to libev |
65 | This module provides an interface to libev |
| 57 | (<http://software.schmorp.de/pkg/libev.html>). While the documentation |
66 | (<http://software.schmorp.de/pkg/libev.html>). While the documentation |
| 58 | below is comprehensive, one might also consult the documentation of |
67 | below is comprehensive, one might also consult the documentation of |
| … | |
… | |
| 66 | can use it through the AnyEvent module, stay portable to other event |
75 | can use it through the AnyEvent module, stay portable to other event |
| 67 | loops (if you don't rely on any watcher types not available through it) |
76 | loops (if you don't rely on any watcher types not available through it) |
| 68 | and still be faster than with any other event loop currently supported |
77 | and still be faster than with any other event loop currently supported |
| 69 | in Perl. |
78 | in Perl. |
| 70 | |
79 | |
|
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80 | PORTING FROM EV 3.X to 4.X |
|
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81 | EV version 4 introduces a number of incompatible changes summarised |
|
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82 | here. According to the depreciation strategy used by libev, there is a |
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83 | compatibility layer in place so programs should continue to run |
|
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84 | unchanged (the XS interface lacks this layer, so programs using that one |
|
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85 | need to be updated). |
|
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86 | |
|
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87 | This compatibility layer will be switched off in some future release. |
|
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88 | |
|
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89 | All changes relevant to Perl are renames of symbols, functions and |
|
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90 | methods: |
|
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91 | |
|
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92 | EV::loop => EV::run |
|
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93 | EV::LOOP_NONBLOCK => EV::RUN_NOWAIT |
|
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94 | EV::LOOP_ONESHOT => EV::RUN_ONCE |
|
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95 | |
|
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96 | EV::unloop => EV::break |
|
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97 | EV::UNLOOP_CANCEL => EV::BREAK_CANCEL |
|
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98 | EV::UNLOOP_ONE => EV::BREAK_ONE |
|
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99 | EV::UNLOOP_ALL => EV::BREAK_ALL |
|
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100 | |
|
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101 | EV::TIMEOUT => EV::TIMER |
|
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102 | |
|
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103 | EV::loop_count => EV::iteration |
|
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104 | EV::loop_depth => EV::depth |
|
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105 | EV::loop_verify => EV::verify |
|
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106 | |
|
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107 | The loop object methods corresponding to the functions above have been |
|
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108 | similarly renamed. |
|
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109 | |
| 71 | MODULE EXPORTS |
110 | MODULE EXPORTS |
| 72 | This module does not export any symbols. |
111 | This module does not export any symbols. |
| 73 | |
112 | |
| 74 | EVENT LOOPS |
113 | EVENT LOOPS |
| 75 | EV supports multiple event loops: There is a single "default event loop" |
114 | EV supports multiple event loops: There is a single "default event loop" |
| … | |
… | |
| 91 | *embed* a kqueue loop into the default loop: running the default loop |
130 | *embed* a kqueue loop into the default loop: running the default loop |
| 92 | will then also service the kqueue loop to some extent. See the example |
131 | will then also service the kqueue loop to some extent. See the example |
| 93 | in the section about embed watchers for an example on how to achieve |
132 | in the section about embed watchers for an example on how to achieve |
| 94 | that. |
133 | that. |
| 95 | |
134 | |
| 96 | $loop = new EV::loop [$flags] |
135 | $loop = new EV::Loop [$flags] |
| 97 | Create a new event loop as per the specified flags. Please refer to |
136 | Create a new event loop as per the specified flags. Please refer to |
| 98 | the "ev_loop_new ()" function description in the libev documentation |
137 | the "ev_loop_new ()" function description in the libev documentation |
| 99 | (<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#GLOBAL_FUNCTI |
138 | (<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#GLOBAL_FUNCTI |
| 100 | ONS>, or locally-installed as EV::libev manpage) for more info. |
139 | ONS>, or locally-installed as EV::libev manpage) for more info. |
| 101 | |
140 | |
| … | |
… | |
| 112 | Must be called after a fork in the child, before entering or |
151 | Must be called after a fork in the child, before entering or |
| 113 | continuing the event loop. An alternative is to use |
152 | continuing the event loop. An alternative is to use |
| 114 | "EV::FLAG_FORKCHECK" which calls this function automatically, at |
153 | "EV::FLAG_FORKCHECK" which calls this function automatically, at |
| 115 | some performance loss (refer to the libev documentation). |
154 | some performance loss (refer to the libev documentation). |
| 116 | |
155 | |
| 117 | $loop->loop_verify |
156 | $loop->verify |
| 118 | Calls "ev_verify" to make internal consistency checks (for debugging |
157 | Calls "ev_verify" to make internal consistency checks (for debugging |
| 119 | libev) and abort the program if any data structures were found to be |
158 | libev) and abort the program if any data structures were found to be |
| 120 | corrupted. |
159 | corrupted. |
| 121 | |
160 | |
| 122 | $loop = EV::default_loop [$flags] |
161 | $loop = EV::default_loop [$flags] |
| … | |
… | |
| 152 | $time = $loop->now |
191 | $time = $loop->now |
| 153 | Returns the time the last event loop iteration has been started. |
192 | Returns the time the last event loop iteration has been started. |
| 154 | This is the time that (relative) timers are based on, and referring |
193 | This is the time that (relative) timers are based on, and referring |
| 155 | to it is usually faster then calling EV::time. |
194 | to it is usually faster then calling EV::time. |
| 156 | |
195 | |
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196 | EV::now_update |
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197 | $loop->now_update |
|
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198 | Establishes the current time by querying the kernel, updating the |
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199 | time returned by "EV::now" in the progress. This is a costly |
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200 | operation and is usually done automatically within "EV::loop". |
|
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201 | |
|
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202 | This function is rarely useful, but when some event callback runs |
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203 | for a very long time without entering the event loop, updating |
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204 | libev's idea of the current time is a good idea. |
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205 | |
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206 | EV::suspend |
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207 | $loop->suspend |
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208 | EV::resume |
|
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209 | $loop->resume |
|
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210 | These two functions suspend and resume a loop, for use when the loop |
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211 | is not used for a while and timeouts should not be processed. |
|
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212 | |
|
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213 | A typical use case would be an interactive program such as a game: |
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214 | When the user presses "^Z" to suspend the game and resumes it an |
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215 | hour later it would be best to handle timeouts as if no time had |
|
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216 | actually passed while the program was suspended. This can be |
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217 | achieved by calling "suspend" in your "SIGTSTP" handler, sending |
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218 | yourself a "SIGSTOP" and calling "resume" directly afterwards to |
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219 | resume timer processing. |
|
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220 | |
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221 | Effectively, all "timer" watchers will be delayed by the time spend |
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222 | between "suspend" and "resume", and all "periodic" watchers will be |
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223 | rescheduled (that is, they will lose any events that would have |
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224 | occured while suspended). |
|
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225 | |
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226 | After calling "suspend" you must not call *any* function on the |
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227 | given loop other than "resume", and you must not call "resume" |
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228 | without a previous call to "suspend". |
|
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229 | |
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230 | Calling "suspend"/"resume" has the side effect of updating the event |
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231 | loop time (see "now_update"). |
|
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232 | |
| 157 | $backend = EV::backend |
233 | $backend = EV::backend |
| 158 | $backend = $loop->backend |
234 | $backend = $loop->backend |
| 159 | Returns an integer describing the backend used by libev |
235 | Returns an integer describing the backend used by libev |
| 160 | (EV::BACKEND_SELECT or EV::BACKEND_EPOLL). |
236 | (EV::BACKEND_SELECT or EV::BACKEND_EPOLL). |
| 161 | |
237 | |
| 162 | EV::loop [$flags] |
238 | EV::run [$flags] |
| 163 | $loop->loop ([$flags]) |
239 | $loop->run ([$flags]) |
| 164 | Begin checking for events and calling callbacks. It returns when a |
240 | Begin checking for events and calling callbacks. It returns when a |
| 165 | callback calls EV::unloop. |
241 | callback calls EV::unloop. |
| 166 | |
242 | |
| 167 | The $flags argument can be one of the following: |
243 | The $flags argument can be one of the following: |
| 168 | |
244 | |
| 169 | 0 as above |
245 | 0 as above |
| 170 | EV::LOOP_ONESHOT block at most once (wait, but do not loop) |
246 | EV::RUN_ONCE block at most once (wait, but do not loop) |
| 171 | EV::LOOP_NONBLOCK do not block at all (fetch/handle events but do not wait) |
247 | EV::RUN_NOWAIT do not block at all (fetch/handle events but do not wait) |
| 172 | |
248 | |
| 173 | EV::unloop [$how] |
249 | EV::break [$how] |
| 174 | $loop->unloop ([$how]) |
250 | $loop->break ([$how]) |
| 175 | When called with no arguments or an argument of EV::UNLOOP_ONE, |
251 | When called with no arguments or an argument of EV::BREAK_ONE, makes |
| 176 | makes the innermost call to EV::loop return. |
252 | the innermost call to EV::loop return. |
| 177 | |
253 | |
| 178 | When called with an argument of EV::UNLOOP_ALL, all calls to |
254 | When called with an argument of EV::BREAK_ALL, all calls to EV::loop |
| 179 | EV::loop will return as fast as possible. |
255 | will return as fast as possible. |
| 180 | |
256 | |
| 181 | $count = EV::loop_count |
257 | When called with an argument of EV::BREAK_CANCEL, any pending break |
| 182 | $count = $loop->loop_count |
258 | will be cancelled. |
|
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259 | |
|
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260 | $count = EV::iteration |
|
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261 | $count = $loop->iteration |
| 183 | Return the number of times the event loop has polled for new events. |
262 | Return the number of times the event loop has polled for new events. |
| 184 | Sometimes useful as a generation counter. |
263 | Sometimes useful as a generation counter. |
| 185 | |
264 | |
| 186 | EV::once $fh_or_undef, $events, $timeout, $cb->($revents) |
265 | EV::once $fh_or_undef, $events, $timeout, $cb->($revents) |
| 187 | $loop->once ($fh_or_undef, $events, $timeout, $cb->($revents)) |
266 | $loop->once ($fh_or_undef, $events, $timeout, $cb->($revents)) |
| … | |
… | |
| 198 | Otherwise a EV::timer with this value will be started. |
277 | Otherwise a EV::timer with this value will be started. |
| 199 | |
278 | |
| 200 | When an error occurs or either the timeout or I/O watcher triggers, |
279 | When an error occurs or either the timeout or I/O watcher triggers, |
| 201 | then the callback will be called with the received event set (in |
280 | then the callback will be called with the received event set (in |
| 202 | general you can expect it to be a combination of "EV::ERROR", |
281 | general you can expect it to be a combination of "EV::ERROR", |
| 203 | "EV::READ", "EV::WRITE" and "EV::TIMEOUT"). |
282 | "EV::READ", "EV::WRITE" and "EV::TIMER"). |
| 204 | |
283 | |
| 205 | EV::once doesn't return anything: the watchers stay active till |
284 | EV::once doesn't return anything: the watchers stay active till |
| 206 | either of them triggers, then they will be stopped and freed, and |
285 | either of them triggers, then they will be stopped and freed, and |
| 207 | the callback invoked. |
286 | the callback invoked. |
| 208 | |
287 | |
| 209 | EV::feed_fd_event ($fd, $revents) |
288 | EV::feed_fd_event $fd, $revents |
| 210 | $loop->feed_fd_event ($fd, $revents) |
289 | $loop->feed_fd_event ($fd, $revents) |
| 211 | Feed an event on a file descriptor into EV. EV will react to this |
290 | Feed an event on a file descriptor into EV. EV will react to this |
| 212 | call as if the readyness notifications specified by $revents (a |
291 | call as if the readyness notifications specified by $revents (a |
| 213 | combination of "EV::READ" and "EV::WRITE") happened on the file |
292 | combination of "EV::READ" and "EV::WRITE") happened on the file |
| 214 | descriptor $fd. |
293 | descriptor $fd. |
| 215 | |
294 | |
| 216 | EV::feed_signal_event ($signal) |
295 | EV::feed_signal_event $signal |
| 217 | Feed a signal event into EV. EV will react to this call as if the |
296 | Feed a signal event into the default loop. EV will react to this |
| 218 | signal specified by $signal had occured. |
297 | call as if the signal specified by $signal had occured. |
|
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298 | |
|
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299 | EV::feed_signal $signal |
|
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300 | Feed a signal event into EV - unlike "EV::feed_signal_event", this |
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301 | works regardless of which loop has registered the signal, and is |
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302 | mainly useful fro custom signal implementations. |
| 219 | |
303 | |
| 220 | EV::set_io_collect_interval $time |
304 | EV::set_io_collect_interval $time |
| 221 | $loop->set_io_collect_interval ($time) |
305 | $loop->set_io_collect_interval ($time) |
| 222 | EV::set_timeout_collect_interval $time |
306 | EV::set_timeout_collect_interval $time |
| 223 | $loop->set_timeout_collect_interval ($time) |
307 | $loop->set_timeout_collect_interval ($time) |
| … | |
… | |
| 226 | the libev documentation at |
310 | the libev documentation at |
| 227 | <http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#FUNCTIONS_CONT |
311 | <http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#FUNCTIONS_CONT |
| 228 | ROLLING_THE_EVENT_LOOP> (locally installed as EV::libev) for a more |
312 | ROLLING_THE_EVENT_LOOP> (locally installed as EV::libev) for a more |
| 229 | detailed discussion. |
313 | detailed discussion. |
| 230 | |
314 | |
|
|
315 | $count = EV::pending_count |
|
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316 | $count = $loop->pending_count |
|
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317 | Returns the number of currently pending watchers. |
|
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318 | |
|
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319 | EV::invoke_pending |
|
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320 | $loop->invoke_pending |
|
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321 | Invoke all currently pending watchers. |
|
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322 | |
| 231 | WATCHER OBJECTS |
323 | WATCHER OBJECTS |
| 232 | A watcher is an object that gets created to record your interest in some |
324 | A watcher is an object that gets created to record your interest in some |
| 233 | event. For instance, if you want to wait for STDIN to become readable, |
325 | event. For instance, if you want to wait for STDIN to become readable, |
| 234 | you would create an EV::io watcher for that: |
326 | you would create an EV::io watcher for that: |
| 235 | |
327 | |
| … | |
… | |
| 245 | |
337 | |
| 246 | Each watcher type has its associated bit in revents, so you can use the |
338 | Each watcher type has its associated bit in revents, so you can use the |
| 247 | same callback for multiple watchers. The event mask is named after the |
339 | same callback for multiple watchers. The event mask is named after the |
| 248 | type, i.e. EV::child sets EV::CHILD, EV::prepare sets EV::PREPARE, |
340 | type, i.e. EV::child sets EV::CHILD, EV::prepare sets EV::PREPARE, |
| 249 | EV::periodic sets EV::PERIODIC and so on, with the exception of I/O |
341 | EV::periodic sets EV::PERIODIC and so on, with the exception of I/O |
| 250 | events (which can set both EV::READ and EV::WRITE bits), and EV::timer |
342 | events (which can set both EV::READ and EV::WRITE bits). |
| 251 | (which uses EV::TIMEOUT). |
|
|
| 252 | |
343 | |
| 253 | In the rare case where one wants to create a watcher but not start it at |
344 | In the rare case where one wants to create a watcher but not start it at |
| 254 | the same time, each constructor has a variant with a trailing "_ns" in |
345 | the same time, each constructor has a variant with a trailing "_ns" in |
| 255 | its name, e.g. EV::io has a non-starting variant EV::io_ns and so on. |
346 | its name, e.g. EV::io has a non-starting variant EV::io_ns and so on. |
| 256 | |
347 | |
| … | |
… | |
| 321 | the watcher isn't pending it does nothing and returns 0. |
412 | the watcher isn't pending it does nothing and returns 0. |
| 322 | |
413 | |
| 323 | $previous_state = $w->keepalive ($bool) |
414 | $previous_state = $w->keepalive ($bool) |
| 324 | Normally, "EV::loop" will return when there are no active watchers |
415 | Normally, "EV::loop" will return when there are no active watchers |
| 325 | (which is a "deadlock" because no progress can be made anymore). |
416 | (which is a "deadlock" because no progress can be made anymore). |
| 326 | This is convinient because it allows you to start your watchers (and |
417 | This is convenient because it allows you to start your watchers (and |
| 327 | your jobs), call "EV::loop" once and when it returns you know that |
418 | your jobs), call "EV::loop" once and when it returns you know that |
| 328 | all your jobs are finished (or they forgot to register some watchers |
419 | all your jobs are finished (or they forgot to register some watchers |
| 329 | for their task :). |
420 | for their task :). |
| 330 | |
421 | |
| 331 | Sometimes, however, this gets in your way, for example when the |
422 | Sometimes, however, this gets in your way, for example when the |
| … | |
… | |
| 522 | Return the time that the watcher is expected to trigger next. |
613 | Return the time that the watcher is expected to trigger next. |
| 523 | |
614 | |
| 524 | SIGNAL WATCHERS - signal me when a signal gets signalled! |
615 | SIGNAL WATCHERS - signal me when a signal gets signalled! |
| 525 | $w = EV::signal $signal, $callback |
616 | $w = EV::signal $signal, $callback |
| 526 | $w = EV::signal_ns $signal, $callback |
617 | $w = EV::signal_ns $signal, $callback |
|
|
618 | $w = $loop->signal ($signal, $callback) |
|
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619 | $w = $loop->signal_ns ($signal, $callback) |
| 527 | Call the callback when $signal is received (the signal can be |
620 | Call the callback when $signal is received (the signal can be |
| 528 | specified by number or by name, just as with "kill" or %SIG). |
621 | specified by number or by name, just as with "kill" or %SIG). |
|
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622 | |
|
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623 | Only one event loop can grab a given signal - attempting to grab the |
|
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624 | same signal from two EV loops will crash the program immediately or |
|
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625 | cause data corruption. |
| 529 | |
626 | |
| 530 | EV will grab the signal for the process (the kernel only allows one |
627 | EV will grab the signal for the process (the kernel only allows one |
| 531 | component to receive a signal at a time) when you start a signal |
628 | component to receive a signal at a time) when you start a signal |
| 532 | watcher, and removes it again when you stop it. Perl does the same |
629 | watcher, and removes it again when you stop it. Perl does the same |
| 533 | when you add/remove callbacks to %SIG, so watch out. |
630 | when you add/remove callbacks to %SIG, so watch out. |
| … | |
… | |
| 707 | $w = $loop->check_ns ($callback) |
804 | $w = $loop->check_ns ($callback) |
| 708 | Call the callback just after the process wakes up again (after it |
805 | Call the callback just after the process wakes up again (after it |
| 709 | has gathered events), but before any other callbacks have been |
806 | has gathered events), but before any other callbacks have been |
| 710 | invoked. |
807 | invoked. |
| 711 | |
808 | |
| 712 | This is used to integrate other event-based software into the EV |
809 | This can be used to integrate other event-based software into the EV |
| 713 | mainloop: You register a prepare callback and in there, you create |
810 | mainloop: You register a prepare callback and in there, you create |
| 714 | io and timer watchers as required by the other software. Here is a |
811 | io and timer watchers as required by the other software. Here is a |
| 715 | real-world example of integrating Net::SNMP (with some details left |
812 | real-world example of integrating Net::SNMP (with some details left |
| 716 | out): |
813 | out): |
| 717 | |
814 | |
| … | |
… | |
| 753 | watchers are destroyed before this can happen (remember EV::check |
850 | watchers are destroyed before this can happen (remember EV::check |
| 754 | gets called first). |
851 | gets called first). |
| 755 | |
852 | |
| 756 | The "check_ns" variant doesn't start (activate) the newly created |
853 | The "check_ns" variant doesn't start (activate) the newly created |
| 757 | watcher. |
854 | watcher. |
|
|
855 | |
|
|
856 | EV::CHECK constant issues |
|
|
857 | Like all other watcher types, there is a bitmask constant for use in |
|
|
858 | $revents and other places. The "EV::CHECK" is special as it has the |
|
|
859 | same name as the "CHECK" sub called by Perl. This doesn't cause big |
|
|
860 | issues on newer perls (beginning with 5.8.9), but it means thatthe |
|
|
861 | constant must be *inlined*, i.e. runtime calls will not work. That |
|
|
862 | means that as long as you always "use EV" and then "EV::CHECK" you |
|
|
863 | are on the safe side. |
| 758 | |
864 | |
| 759 | FORK WATCHERS - the audacity to resume the event loop after a fork |
865 | FORK WATCHERS - the audacity to resume the event loop after a fork |
| 760 | Fork watchers are called when a "fork ()" was detected. The invocation |
866 | Fork watchers are called when a "fork ()" was detected. The invocation |
| 761 | is done before the event loop blocks next and before "check" watchers |
867 | is done before the event loop blocks next and before "check" watchers |
| 762 | are being called, and only in the child after the fork. |
868 | are being called, and only in the child after the fork. |
| … | |
… | |
| 783 | |
889 | |
| 784 | In short, this watcher is most useful on BSD systems without working |
890 | In short, this watcher is most useful on BSD systems without working |
| 785 | kqueue to still be able to handle a large number of sockets: |
891 | kqueue to still be able to handle a large number of sockets: |
| 786 | |
892 | |
| 787 | my $socket_loop; |
893 | my $socket_loop; |
| 788 | |
894 | |
| 789 | # check wether we use SELECT or POLL _and_ KQUEUE is supported |
895 | # check wether we use SELECT or POLL _and_ KQUEUE is supported |
| 790 | if ( |
896 | if ( |
| 791 | (EV::backend & (EV::BACKEND_POLL | EV::BACKEND_SELECT)) |
897 | (EV::backend & (EV::BACKEND_POLL | EV::BACKEND_SELECT)) |
| 792 | && (EV::supported_backends & EV::embeddable_backends & EV::BACKEND_KQUEUE) |
898 | && (EV::supported_backends & EV::embeddable_backends & EV::BACKEND_KQUEUE) |
| 793 | ) { |
899 | ) { |
| 794 | # use kqueue for sockets |
900 | # use kqueue for sockets |
| 795 | $socket_loop = new EV::Loop EV::BACKEND_KQUEUE | EV::FLAG_NOENV; |
901 | $socket_loop = new EV::Loop EV::BACKEND_KQUEUE | EV::FLAG_NOENV; |
| 796 | } |
902 | } |
| 797 | |
903 | |
| 798 | # use the default loop otherwise |
904 | # use the default loop otherwise |
| 799 | $socket_loop ||= EV::default_loop; |
905 | $socket_loop ||= EV::default_loop; |
| 800 | |
906 | |
| 801 | $w = EV::embed $otherloop[, $callback] |
907 | $w = EV::embed $otherloop[, $callback] |
| 802 | $w = EV::embed_ns $otherloop[, $callback] |
908 | $w = EV::embed_ns $otherloop[, $callback] |
| 803 | $w = $loop->embed ($otherloop[, $callback]) |
909 | $w = $loop->embed ($otherloop[, $callback]) |
| … | |
… | |
| 810 | The "embed_ns" variant doesn't start (activate) the newly created |
916 | The "embed_ns" variant doesn't start (activate) the newly created |
| 811 | watcher. |
917 | watcher. |
| 812 | |
918 | |
| 813 | ASYNC WATCHERS - how to wake up another event loop |
919 | ASYNC WATCHERS - how to wake up another event loop |
| 814 | Async watchers are provided by EV, but have little use in perl directly, |
920 | Async watchers are provided by EV, but have little use in perl directly, |
| 815 | as perl neither supports threads nor direct access to signal handlers or |
921 | as perl neither supports threads running in parallel nor direct access |
| 816 | other contexts where they could be of value. |
922 | to signal handlers or other contexts where they could be of value. |
| 817 | |
923 | |
| 818 | It is, however, possible to use them from the XS level. |
924 | It is, however, possible to use them from the XS level. |
| 819 | |
925 | |
| 820 | Please see the libev documentation for further details. |
926 | Please see the libev documentation for further details. |
| 821 | |
927 | |
| … | |
… | |
| 840 | my $async_check = EV::check sub { }; |
946 | my $async_check = EV::check sub { }; |
| 841 | |
947 | |
| 842 | This ensures that perl gets into control for a short time to handle any |
948 | This ensures that perl gets into control for a short time to handle any |
| 843 | pending signals, and also ensures (slightly) slower overall operation. |
949 | pending signals, and also ensures (slightly) slower overall operation. |
| 844 | |
950 | |
| 845 | THREADS |
951 | ITHREADS |
| 846 | Threads are not supported by this module in any way. Perl pseudo-threads |
952 | Ithreads are not supported by this module in any way. Perl |
| 847 | is evil stuff and must die. As soon as Perl gains real threads I will |
953 | pseudo-threads is evil stuff and must die. Real threads as provided by |
| 848 | work on thread support for it. |
954 | Coro are fully supported (and enhanced support is available via |
|
|
955 | Coro::EV). |
| 849 | |
956 | |
| 850 | FORK |
957 | FORK |
| 851 | Most of the "improved" event delivering mechanisms of modern operating |
958 | Most of the "improved" event delivering mechanisms of modern operating |
| 852 | systems have quite a few problems with fork(2) (to put it bluntly: it is |
959 | systems have quite a few problems with fork(2) (to put it bluntly: it is |
| 853 | not supported and usually destructive). Libev makes it possible to work |
960 | not supported and usually destructive). Libev makes it possible to work |
| … | |
… | |
| 863 | |
970 | |
| 864 | On win32, there is no notion of fork so all this doesn't apply, of |
971 | On win32, there is no notion of fork so all this doesn't apply, of |
| 865 | course. |
972 | course. |
| 866 | |
973 | |
| 867 | SEE ALSO |
974 | SEE ALSO |
| 868 | EV::ADNS (asynchronous DNS), Glib::EV (makes Glib/Gtk2 use EV as event |
975 | EV::MakeMaker - MakeMaker interface to XS API, EV::ADNS (asynchronous |
| 869 | loop), EV::Glib (embed Glib into EV), Coro::EV (efficient coroutines |
976 | DNS), Glib::EV (makes Glib/Gtk2 use EV as event loop), EV::Glib (embed |
| 870 | with EV), Net::SNMP::EV (asynchronous SNMP), AnyEvent for event-loop |
977 | Glib into EV), Coro::EV (efficient thread integration), Net::SNMP::EV |
| 871 | agnostic and portable event driven programming. |
978 | (asynchronous SNMP), AnyEvent for event-loop agnostic and portable event |
|
|
979 | driven programming. |
| 872 | |
980 | |
| 873 | AUTHOR |
981 | AUTHOR |
| 874 | Marc Lehmann <schmorp@schmorp.de> |
982 | Marc Lehmann <schmorp@schmorp.de> |
| 875 | http://home.schmorp.de/ |
983 | http://home.schmorp.de/ |
| 876 | |
984 | |
