… | |
… | |
10 | |
10 | |
11 | my $w = EV::timer 2, 0, sub { |
11 | my $w = EV::timer 2, 0, sub { |
12 | warn "is called after 2s"; |
12 | warn "is called after 2s"; |
13 | }; |
13 | }; |
14 | |
14 | |
15 | my $w = EV::timer 2, 1, sub { |
15 | my $w = EV::timer 2, 2, sub { |
16 | warn "is called roughly every 2s (repeat = 1)"; |
16 | warn "is called roughly every 2s (repeat = 2)"; |
17 | }; |
17 | }; |
18 | |
18 | |
19 | undef $w; # destroy event watcher again |
19 | undef $w; # destroy event watcher again |
20 | |
20 | |
21 | my $w = EV::periodic 0, 60, sub { |
21 | my $w = EV::periodic 0, 60, 0, sub { |
22 | warn "is called every minute, on the minute, exactly"; |
22 | warn "is called every minute, on the minute, exactly"; |
23 | }; |
23 | }; |
24 | |
24 | |
25 | # IO |
25 | # IO |
26 | |
26 | |
27 | my $w = EV::io *STDIN, EV::READ, sub { |
27 | my $w = EV::io *STDIN, EV::READ, sub { |
28 | my ($w, $revents) = @_; # all callbacks get the watcher object and event mask |
28 | my ($w, $revents) = @_; # all callbacks receive the watcher and event mask |
29 | warn "stdin is readable, you entered: ", <STDIN>; |
29 | warn "stdin is readable, you entered: ", <STDIN>; |
30 | }; |
30 | }; |
31 | |
31 | |
32 | # SIGNALS |
32 | # SIGNALS |
33 | |
33 | |
34 | my $w = EV::signal 'QUIT', sub { |
34 | my $w = EV::signal 'QUIT', sub { |
35 | warn "sigquit received\n"; |
35 | warn "sigquit received\n"; |
36 | }; |
36 | }; |
37 | |
37 | |
38 | my $w = EV::signal 3, sub { |
|
|
39 | warn "sigquit received (this is GNU/Linux, right?)\n"; |
|
|
40 | }; |
|
|
41 | |
|
|
42 | # CHILD/PID STATUS CHANGES |
38 | # CHILD/PID STATUS CHANGES |
43 | |
39 | |
44 | my $w = EV::child 666, sub { |
40 | my $w = EV::child 666, sub { |
45 | my ($w, $revents) = @_; |
41 | my ($w, $revents) = @_; |
46 | # my $pid = $w->rpid; |
|
|
47 | my $status = $w->rstatus; |
42 | my $status = $w->rstatus; |
48 | }; |
43 | }; |
|
|
44 | |
|
|
45 | # STAT CHANGES |
|
|
46 | my $w = EV::stat "/etc/passwd", 10, sub { |
|
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47 | my ($w, $revents) = @_; |
|
|
48 | warn $w->path, " has changed somehow.\n"; |
|
|
49 | }; |
49 | |
50 | |
50 | # MAINLOOP |
51 | # MAINLOOP |
51 | EV::loop; # loop until EV::loop_done is called |
52 | EV::loop; # 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 |
53 | EV::loop EV::LOOP_ONESHOT; # block until at least one event could be handled |
53 | EV::loop EV::LOOP_NONBLOCK; # try to handle same events, but do not block |
54 | EV::loop EV::LOOP_NONBLOCK; # try to handle same events, but do not block |
54 | |
55 | |
55 | =head1 DESCRIPTION |
56 | =head1 DESCRIPTION |
56 | |
57 | |
57 | This module provides an interface to libev |
58 | This module provides an interface to libev |
58 | (L<http://software.schmorp.de/pkg/libev.html>). |
59 | (L<http://software.schmorp.de/pkg/libev.html>). While the documentation |
|
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60 | below is comprehensive, one might also consult the documentation of libev |
|
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61 | itself (L<http://cvs.schmorp.de/libev/ev.html>) for more subtle details on |
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62 | watcher semantics or some discussion on the available backends, or how to |
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63 | force a specific backend with C<LIBEV_FLAGS>. |
59 | |
64 | |
60 | =cut |
65 | =cut |
61 | |
66 | |
62 | package EV; |
67 | package EV; |
63 | |
68 | |
64 | use strict; |
69 | use strict; |
65 | |
70 | |
66 | BEGIN { |
71 | BEGIN { |
67 | our $VERSION = '0.5'; |
72 | our $VERSION = '1.4'; |
68 | use XSLoader; |
73 | use XSLoader; |
69 | XSLoader::load "EV", $VERSION; |
74 | XSLoader::load "EV", $VERSION; |
70 | } |
75 | } |
71 | |
76 | |
72 | @EV::Io::ISA = |
77 | @EV::IO::ISA = |
73 | @EV::Timer::ISA = |
78 | @EV::Timer::ISA = |
74 | @EV::Periodic::ISA = |
79 | @EV::Periodic::ISA = |
75 | @EV::Signal::ISA = |
80 | @EV::Signal::ISA = |
|
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81 | @EV::Child::ISA = |
|
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82 | @EV::Stat::ISA = |
76 | @EV::Idle::ISA = |
83 | @EV::Idle::ISA = |
77 | @EV::Prepare::ISA = |
84 | @EV::Prepare::ISA = |
78 | @EV::Check::ISA = |
85 | @EV::Check::ISA = |
79 | @EV::Child::ISA = "EV::Watcher"; |
86 | @EV::Embed::ISA = |
|
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87 | @EV::Fork::ISA = |
|
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88 | "EV::Watcher"; |
80 | |
89 | |
81 | =head1 BASIC INTERFACE |
90 | =head1 BASIC INTERFACE |
82 | |
91 | |
83 | =over 4 |
92 | =over 4 |
84 | |
93 | |
… | |
… | |
98 | |
107 | |
99 | Returns the time the last event loop iteration has been started. This |
108 | Returns the time the last event loop iteration has been started. This |
100 | is the time that (relative) timers are based on, and refering to it is |
109 | is the time that (relative) timers are based on, and refering to it is |
101 | usually faster then calling EV::time. |
110 | usually faster then calling EV::time. |
102 | |
111 | |
103 | =item $method = EV::ev_method |
112 | =item $method = EV::method |
104 | |
113 | |
105 | Returns an integer describing the backend used by libev (EV::METHOD_SELECT |
114 | Returns an integer describing the backend used by libev (EV::METHOD_SELECT |
106 | or EV::METHOD_EPOLL). |
115 | or EV::METHOD_EPOLL). |
107 | |
116 | |
108 | =item EV::loop [$flags] |
117 | =item EV::loop [$flags] |
109 | |
118 | |
110 | Begin checking for events and calling callbacks. It returns when a |
119 | Begin checking for events and calling callbacks. It returns when a |
111 | callback calls EV::loop_done. |
120 | callback calls EV::unloop. |
112 | |
121 | |
113 | The $flags argument can be one of the following: |
122 | The $flags argument can be one of the following: |
114 | |
123 | |
115 | 0 as above |
124 | 0 as above |
116 | EV::LOOP_ONESHOT block at most once (wait, but do not loop) |
125 | EV::LOOP_ONESHOT block at most once (wait, but do not loop) |
117 | EV::LOOP_NONBLOCK do not block at all (fetch/handle events but do not wait) |
126 | EV::LOOP_NONBLOCK do not block at all (fetch/handle events but do not wait) |
118 | |
127 | |
119 | =item EV::loop_done [$how] |
128 | =item EV::unloop [$how] |
120 | |
129 | |
121 | When called with no arguments or an argument of 1, makes the innermost |
130 | When called with no arguments or an argument of EV::UNLOOP_ONE, makes the |
122 | call to EV::loop return. |
131 | innermost call to EV::loop return. |
123 | |
132 | |
124 | When called with an agrument of 2, all calls to EV::loop will return as |
133 | When called with an argument of EV::UNLOOP_ALL, all calls to EV::loop will return as |
125 | fast as possible. |
134 | fast as possible. |
126 | |
135 | |
127 | =back |
136 | =item EV::once $fh_or_undef, $events, $timeout, $cb->($revents) |
128 | |
137 | |
|
|
138 | This function rolls together an I/O and a timer watcher for a single |
|
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139 | one-shot event without the need for managing a watcher object. |
|
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140 | |
|
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141 | If C<$fh_or_undef> is a filehandle or file descriptor, then C<$events> |
|
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142 | must be a bitset containing either C<EV::READ>, C<EV::WRITE> or C<EV::READ |
|
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143 | | EV::WRITE>, indicating the type of I/O event you want to wait for. If |
|
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144 | you do not want to wait for some I/O event, specify C<undef> for |
|
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145 | C<$fh_or_undef> and C<0> for C<$events>). |
|
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146 | |
|
|
147 | If timeout is C<undef> or negative, then there will be no |
|
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148 | timeout. Otherwise a EV::timer with this value will be started. |
|
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149 | |
|
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150 | When an error occurs or either the timeout or I/O watcher triggers, then |
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151 | the callback will be called with the received event set (in general |
|
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152 | you can expect it to be a combination of C<EV:ERROR>, C<EV::READ>, |
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153 | C<EV::WRITE> and C<EV::TIMEOUT>). |
|
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154 | |
|
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155 | EV::once doesn't return anything: the watchers stay active till either |
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156 | of them triggers, then they will be stopped and freed, and the callback |
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157 | invoked. |
|
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158 | |
|
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159 | =back |
|
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160 | |
129 | =head2 WATCHER |
161 | =head2 WATCHER OBJECTS |
130 | |
162 | |
131 | A watcher is an object that gets created to record your interest in some |
163 | A watcher is an object that gets created to record your interest in some |
132 | event. For instance, if you want to wait for STDIN to become readable, you |
164 | event. For instance, if you want to wait for STDIN to become readable, you |
133 | would create an EV::io watcher for that: |
165 | would create an EV::io watcher for that: |
134 | |
166 | |
… | |
… | |
159 | |
191 | |
160 | Also, all methods changing some aspect of a watcher (->set, ->priority, |
192 | Also, all methods changing some aspect of a watcher (->set, ->priority, |
161 | ->fh and so on) automatically stop and start it again if it is active, |
193 | ->fh and so on) automatically stop and start it again if it is active, |
162 | which means pending events get lost. |
194 | which means pending events get lost. |
163 | |
195 | |
164 | =head2 WATCHER TYPES |
196 | =head2 COMMON WATCHER METHODS |
165 | |
197 | |
166 | Now lets move to the existing watcher types and asociated methods. |
198 | This section lists methods common to all watchers. |
167 | |
|
|
168 | The following methods are available for all watchers. Then followes a |
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169 | description of each watcher constructor (EV::io, EV::timer, EV::periodic, |
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170 | EV::signal, EV::child, EV::idle, EV::prepare and EV::check), followed by |
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171 | any type-specific methods (if any). |
|
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172 | |
199 | |
173 | =over 4 |
200 | =over 4 |
174 | |
201 | |
175 | =item $w->start |
202 | =item $w->start |
176 | |
203 | |
… | |
… | |
185 | regardless of wether the watcher was active or not. |
212 | regardless of wether the watcher was active or not. |
186 | |
213 | |
187 | =item $bool = $w->is_active |
214 | =item $bool = $w->is_active |
188 | |
215 | |
189 | Returns true if the watcher is active, false otherwise. |
216 | Returns true if the watcher is active, false otherwise. |
|
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217 | |
|
|
218 | =item $current_data = $w->data |
|
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219 | |
|
|
220 | =item $old_data = $w->data ($new_data) |
|
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221 | |
|
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222 | Queries a freely usable data scalar on the watcher and optionally changes |
|
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223 | it. This is a way to associate custom data with a watcher: |
|
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224 | |
|
|
225 | my $w = EV::timer 60, 0, sub { |
|
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226 | warn $_[0]->data; |
|
|
227 | }; |
|
|
228 | $w->data ("print me!"); |
190 | |
229 | |
191 | =item $current_cb = $w->cb |
230 | =item $current_cb = $w->cb |
192 | |
231 | |
193 | =item $old_cb = $w->cb ($new_cb) |
232 | =item $old_cb = $w->cb ($new_cb) |
194 | |
233 | |
… | |
… | |
203 | watchers with higher priority will be invoked first. The valid range of |
242 | watchers with higher priority will be invoked first. The valid range of |
204 | priorities lies between EV::MAXPRI (default 2) and EV::MINPRI (default |
243 | priorities lies between EV::MAXPRI (default 2) and EV::MINPRI (default |
205 | -2). If the priority is outside this range it will automatically be |
244 | -2). If the priority is outside this range it will automatically be |
206 | normalised to the nearest valid priority. |
245 | normalised to the nearest valid priority. |
207 | |
246 | |
208 | The default priority of any newly-created weatcher is 0. |
247 | The default priority of any newly-created watcher is 0. |
|
|
248 | |
|
|
249 | Note that the priority semantics have not yet been fleshed out and are |
|
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250 | subject to almost certain change. |
209 | |
251 | |
210 | =item $w->trigger ($revents) |
252 | =item $w->trigger ($revents) |
211 | |
253 | |
212 | Call the callback *now* with the given event mask. |
254 | Call the callback *now* with the given event mask. |
213 | |
255 | |
|
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256 | =item $previous_state = $w->keepalive ($bool) |
|
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257 | |
|
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258 | Normally, C<EV::loop> will return when there are no active watchers |
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259 | (which is a "deadlock" because no progress can be made anymore). This is |
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260 | convinient because it allows you to start your watchers (and your jobs), |
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261 | call C<EV::loop> once and when it returns you know that all your jobs are |
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262 | finished (or they forgot to register some watchers for their task :). |
|
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263 | |
|
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264 | Sometimes, however, this gets in your way, for example when you the module |
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265 | that calls C<EV::loop> (usually the main program) is not the same module |
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266 | as a long-living watcher (for example a DNS client module written by |
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267 | somebody else even). Then you might want any outstanding requests to be |
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268 | handled, but you would not want to keep C<EV::loop> from returning just |
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269 | because you happen to have this long-running UDP port watcher. |
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270 | |
|
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271 | In this case you can clear the keepalive status, which means that even |
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272 | though your watcher is active, it won't keep C<EV::loop> from returning. |
|
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273 | |
|
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274 | The initial value for keepalive is true (enabled), and you cna change it |
|
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275 | any time. |
|
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276 | |
|
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277 | Example: Register an IO watcher for some UDP socket but do not keep the |
|
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278 | event loop from running just because of that watcher. |
|
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279 | |
|
|
280 | my $udp_socket = ... |
|
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281 | my $udp_watcher = EV::io $udp_socket, EV::READ, sub { ... }; |
|
|
282 | $udp_watcher->keepalive (0); |
|
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283 | |
|
|
284 | =back |
|
|
285 | |
|
|
286 | |
|
|
287 | =head2 WATCHER TYPES |
|
|
288 | |
|
|
289 | Each of the following subsections describes a single watcher type. |
|
|
290 | |
|
|
291 | =head3 IO WATCHERS - is this file descriptor readable or writable? |
|
|
292 | |
|
|
293 | =over 4 |
214 | |
294 | |
215 | =item $w = EV::io $fileno_or_fh, $eventmask, $callback |
295 | =item $w = EV::io $fileno_or_fh, $eventmask, $callback |
216 | |
296 | |
217 | =item $w = EV::io_ns $fileno_or_fh, $eventmask, $callback |
297 | =item $w = EV::io_ns $fileno_or_fh, $eventmask, $callback |
218 | |
298 | |
219 | As long as the returned watcher object is alive, call the C<$callback> |
299 | As long as the returned watcher object is alive, call the C<$callback> |
220 | when the events specified in C<$eventmask>. |
300 | when at least one of events specified in C<$eventmask> occurs. |
221 | |
301 | |
222 | The $eventmask can be one or more of these constants ORed together: |
302 | The $eventmask can be one or more of these constants ORed together: |
223 | |
303 | |
224 | EV::READ wait until read() wouldn't block anymore |
304 | EV::READ wait until read() wouldn't block anymore |
225 | EV::WRITE wait until write() wouldn't block anymore |
305 | EV::WRITE wait until write() wouldn't block anymore |
… | |
… | |
241 | |
321 | |
242 | =item $old_eventmask = $w->events ($new_eventmask) |
322 | =item $old_eventmask = $w->events ($new_eventmask) |
243 | |
323 | |
244 | Returns the previously set event mask and optionally set a new one. |
324 | Returns the previously set event mask and optionally set a new one. |
245 | |
325 | |
|
|
326 | =back |
|
|
327 | |
|
|
328 | |
|
|
329 | =head3 TIMER WATCHERS - relative and optionally repeating timeouts |
|
|
330 | |
|
|
331 | =over 4 |
246 | |
332 | |
247 | =item $w = EV::timer $after, $repeat, $callback |
333 | =item $w = EV::timer $after, $repeat, $callback |
248 | |
334 | |
249 | =item $w = EV::timer_ns $after, $repeat, $callback |
335 | =item $w = EV::timer_ns $after, $repeat, $callback |
250 | |
336 | |
251 | Calls the callback after C<$after> seconds. If C<$repeat> is non-zero, |
337 | Calls the callback after C<$after> seconds (which may be fractional). If |
252 | the timer will be restarted (with the $repeat value as $after) after the |
338 | C<$repeat> is non-zero, the timer will be restarted (with the $repeat |
253 | callback returns. |
339 | value as $after) after the callback returns. |
254 | |
340 | |
255 | This means that the callback would be called roughly after C<$after> |
341 | This means that the callback would be called roughly after C<$after> |
256 | seconds, and then every C<$repeat> seconds. "Roughly" because the time of |
342 | seconds, and then every C<$repeat> seconds. The timer does his best not |
257 | callback processing is not taken into account, so the timer will slowly |
343 | to drift, but it will not invoke the timer more often then once per event |
258 | drift. If that isn't acceptable, look at EV::periodic. |
344 | loop iteration, and might drift in other cases. If that isn't acceptable, |
|
|
345 | look at EV::periodic, which can provide long-term stable timers. |
259 | |
346 | |
260 | The timer is based on a monotonic clock, that is if somebody is sitting |
347 | The timer is based on a monotonic clock, that is, if somebody is sitting |
261 | in front of the machine while the timer is running and changes the system |
348 | in front of the machine while the timer is running and changes the system |
262 | clock, the timer will nevertheless run (roughly) the same time. |
349 | clock, the timer will nevertheless run (roughly) the same time. |
263 | |
350 | |
264 | The C<timer_ns> variant doesn't start (activate) the newly created watcher. |
351 | The C<timer_ns> variant doesn't start (activate) the newly created watcher. |
265 | |
352 | |
266 | =item $w->set ($after, $repeat) |
353 | =item $w->set ($after, $repeat) |
267 | |
354 | |
268 | Reconfigures the watcher, see the constructor above for details. Can be at |
355 | Reconfigures the watcher, see the constructor above for details. Can be called at |
269 | any time. |
356 | any time. |
270 | |
357 | |
271 | =item $w->again |
358 | =item $w->again |
272 | |
359 | |
273 | Similar to the C<start> method, but has special semantics for repeating timers: |
360 | Similar to the C<start> method, but has special semantics for repeating timers: |
|
|
361 | |
|
|
362 | If the timer is active and non-repeating, it will be stopped. |
274 | |
363 | |
275 | If the timer is active and repeating, reset the timeout to occur |
364 | If the timer is active and repeating, reset the timeout to occur |
276 | C<$repeat> seconds after now. |
365 | C<$repeat> seconds after now. |
277 | |
366 | |
278 | If the timer is active and non-repeating, it will be stopped. |
|
|
279 | |
|
|
280 | If the timer is in active and repeating, start it. |
367 | If the timer is inactive and repeating, start it using the repeat value. |
281 | |
368 | |
282 | Otherwise do nothing. |
369 | Otherwise do nothing. |
283 | |
370 | |
284 | This behaviour is useful when you have a timeout for some IO |
371 | This behaviour is useful when you have a timeout for some IO |
285 | operation. You create a timer object with the same value for C<$after> and |
372 | operation. You create a timer object with the same value for C<$after> and |
286 | C<$repeat>, and then, in the read/write watcher, run the C<again> method |
373 | C<$repeat>, and then, in the read/write watcher, run the C<again> method |
287 | on the timeout. |
374 | on the timeout. |
288 | |
375 | |
|
|
376 | =back |
289 | |
377 | |
|
|
378 | |
|
|
379 | =head3 PERIODIC WATCHERS - to cron or not to cron? |
|
|
380 | |
|
|
381 | =over 4 |
|
|
382 | |
290 | =item $w = EV::periodic $at, $interval, $callback |
383 | =item $w = EV::periodic $at, $interval, $reschedule_cb, $callback |
291 | |
384 | |
292 | =item $w = EV::periodic_ns $at, $interval, $callback |
385 | =item $w = EV::periodic_ns $at, $interval, $reschedule_cb, $callback |
293 | |
386 | |
294 | Similar to EV::timer, but the time is given as an absolute point in time |
387 | Similar to EV::timer, but is not based on relative timeouts but on |
295 | (C<$at>), plus an optional C<$interval>. |
388 | absolute times. Apart from creating "simple" timers that trigger "at" the |
|
|
389 | specified time, it can also be used for non-drifting absolute timers and |
|
|
390 | more complex, cron-like, setups that are not adversely affected by time |
|
|
391 | jumps (i.e. when the system clock is changed by explicit date -s or other |
|
|
392 | means such as ntpd). It is also the most complex watcher type in EV. |
296 | |
393 | |
297 | If the C<$interval> is zero, then the callback will be called at the time |
394 | It has three distinct "modes": |
298 | C<$at> if that is in the future, or as soon as possible if it is in the |
|
|
299 | past. It will not automatically repeat. |
|
|
300 | |
395 | |
301 | If the C<$interval> is nonzero, then the watcher will always be scheduled |
396 | =over 4 |
302 | to time out at the next C<$at + N * $interval> time. |
|
|
303 | |
397 | |
304 | This can be used to schedule a callback to run at very regular intervals, |
398 | =item * absolute timer ($interval = $reschedule_cb = 0) |
305 | as long as the processing time is less then the interval (otherwise |
399 | |
306 | obviously events will be skipped). |
400 | This time simply fires at the wallclock time C<$at> and doesn't repeat. It |
|
|
401 | will not adjust when a time jump occurs, that is, if it is to be run |
|
|
402 | at January 1st 2011 then it will run when the system time reaches or |
|
|
403 | surpasses this time. |
|
|
404 | |
|
|
405 | =item * non-repeating interval timer ($interval > 0, $reschedule_cb = 0) |
|
|
406 | |
|
|
407 | In this mode the watcher will always be scheduled to time out at the |
|
|
408 | next C<$at + N * $interval> time (for some integer N) and then repeat, |
|
|
409 | regardless of any time jumps. |
|
|
410 | |
|
|
411 | This can be used to create timers that do not drift with respect to system |
|
|
412 | time: |
|
|
413 | |
|
|
414 | my $hourly = EV::periodic 0, 3600, 0, sub { print "once/hour\n" }; |
|
|
415 | |
|
|
416 | That doesn't mean there will always be 3600 seconds in between triggers, |
|
|
417 | but only that the the clalback will be called when the system time shows a |
|
|
418 | full hour (UTC). |
307 | |
419 | |
308 | Another way to think about it (for the mathematically inclined) is that |
420 | Another way to think about it (for the mathematically inclined) is that |
309 | EV::periodic will try to run the callback at the next possible time where |
421 | EV::periodic will try to run the callback in this mode at the next |
310 | C<$time = $at (mod $interval)>, regardless of any time jumps. |
422 | possible time where C<$time = $at (mod $interval)>, regardless of any time |
|
|
423 | jumps. |
311 | |
424 | |
312 | This periodic timer is based on "wallclock time", that is, if the clock |
425 | =item * manual reschedule mode ($reschedule_cb = coderef) |
313 | changes (C<ntp>, C<date -s> etc.), then the timer will nevertheless run at |
426 | |
314 | the specified time. This means it will never drift (it might jitter, but |
427 | In this mode $interval and $at are both being ignored. Instead, each |
315 | it will not drift). |
428 | time the periodic watcher gets scheduled, the reschedule callback |
|
|
429 | ($reschedule_cb) will be called with the watcher as first, and the current |
|
|
430 | time as second argument. |
|
|
431 | |
|
|
432 | I<This callback MUST NOT stop or destroy this or any other periodic |
|
|
433 | watcher, ever>. If you need to stop it, return 1e30 and stop it |
|
|
434 | afterwards. |
|
|
435 | |
|
|
436 | It must return the next time to trigger, based on the passed time value |
|
|
437 | (that is, the lowest time value larger than to the second argument). It |
|
|
438 | will usually be called just before the callback will be triggered, but |
|
|
439 | might be called at other times, too. |
|
|
440 | |
|
|
441 | This can be used to create very complex timers, such as a timer that |
|
|
442 | triggers on each midnight, local time (actually 24 hours after the last |
|
|
443 | midnight, to keep the example simple. If you know a way to do it correctly |
|
|
444 | in about the same space (without requiring elaborate modules), drop me a |
|
|
445 | note :): |
|
|
446 | |
|
|
447 | my $daily = EV::periodic 0, 0, sub { |
|
|
448 | my ($w, $now) = @_; |
|
|
449 | |
|
|
450 | use Time::Local (); |
|
|
451 | my (undef, undef, undef, $d, $m, $y) = localtime $now; |
|
|
452 | 86400 + Time::Local::timelocal 0, 0, 0, $d, $m, $y |
|
|
453 | }, sub { |
|
|
454 | print "it's midnight or likely shortly after, now\n"; |
|
|
455 | }; |
|
|
456 | |
|
|
457 | =back |
316 | |
458 | |
317 | The C<periodic_ns> variant doesn't start (activate) the newly created watcher. |
459 | The C<periodic_ns> variant doesn't start (activate) the newly created watcher. |
318 | |
460 | |
319 | =item $w->set ($at, $interval) |
461 | =item $w->set ($at, $interval, $reschedule_cb) |
320 | |
462 | |
321 | Reconfigures the watcher, see the constructor above for details. Can be at |
463 | Reconfigures the watcher, see the constructor above for details. Can be called at |
322 | any time. |
464 | any time. |
323 | |
465 | |
|
|
466 | =item $w->again |
|
|
467 | |
|
|
468 | Simply stops and starts the watcher again. |
|
|
469 | |
|
|
470 | =back |
|
|
471 | |
|
|
472 | |
|
|
473 | =head3 SIGNAL WATCHERS - signal me when a signal gets signalled! |
|
|
474 | |
|
|
475 | =over 4 |
324 | |
476 | |
325 | =item $w = EV::signal $signal, $callback |
477 | =item $w = EV::signal $signal, $callback |
326 | |
478 | |
327 | =item $w = EV::signal_ns $signal, $callback |
479 | =item $w = EV::signal_ns $signal, $callback |
328 | |
480 | |
329 | Call the callback when $signal is received (the signal can be specified |
481 | Call the callback when $signal is received (the signal can be specified by |
330 | by number or by name, just as with kill or %SIG). |
482 | number or by name, just as with C<kill> or C<%SIG>). |
331 | |
483 | |
332 | EV will grab the signal for the process (the kernel only allows one |
484 | EV will grab the signal for the process (the kernel only allows one |
333 | component to receive a signal at a time) when you start a signal watcher, |
485 | component to receive a signal at a time) when you start a signal watcher, |
334 | and removes it again when you stop it. Perl does the same when you |
486 | and removes it again when you stop it. Perl does the same when you |
335 | add/remove callbacks to %SIG, so watch out. |
487 | add/remove callbacks to C<%SIG>, so watch out. |
336 | |
488 | |
337 | You can have as many signal watchers per signal as you want. |
489 | You can have as many signal watchers per signal as you want. |
338 | |
490 | |
339 | The C<signal_ns> variant doesn't start (activate) the newly created watcher. |
491 | The C<signal_ns> variant doesn't start (activate) the newly created watcher. |
340 | |
492 | |
341 | =item $w->set ($signal) |
493 | =item $w->set ($signal) |
342 | |
494 | |
343 | Reconfigures the watcher, see the constructor above for details. Can be at |
495 | Reconfigures the watcher, see the constructor above for details. Can be |
344 | any time. |
496 | called at any time. |
345 | |
497 | |
346 | =item $current_signum = $w->signal |
498 | =item $current_signum = $w->signal |
347 | |
499 | |
348 | =item $old_signum = $w->signal ($new_signal) |
500 | =item $old_signum = $w->signal ($new_signal) |
349 | |
501 | |
350 | Returns the previously set signal (always as a number not name) and |
502 | Returns the previously set signal (always as a number not name) and |
351 | optionally set a new one. |
503 | optionally set a new one. |
352 | |
504 | |
|
|
505 | =back |
|
|
506 | |
|
|
507 | |
|
|
508 | =head3 CHILD WATCHERS - watch out for process status changes |
|
|
509 | |
|
|
510 | =over 4 |
353 | |
511 | |
354 | =item $w = EV::child $pid, $callback |
512 | =item $w = EV::child $pid, $callback |
355 | |
513 | |
356 | =item $w = EV::child_ns $pid, $callback |
514 | =item $w = EV::child_ns $pid, $callback |
357 | |
515 | |
358 | Call the callback when a status change for pid C<$pid> (or any pid |
516 | Call the callback when a status change for pid C<$pid> (or any pid if |
359 | if C<$pid> is 0) has been received. More precisely: when the process |
517 | C<$pid> is 0) has been received. More precisely: when the process receives |
360 | receives a SIGCHLD, EV will fetch the outstanding exit/wait status for all |
518 | a C<SIGCHLD>, EV will fetch the outstanding exit/wait status for all |
361 | changed/zombie children and call the callback. |
519 | changed/zombie children and call the callback. |
362 | |
520 | |
363 | You can access both status and pid by using the C<rstatus> and C<rpid> |
521 | It is valid (and fully supported) to install a child watcher after a child |
364 | methods on the watcher object. |
522 | has exited but before the event loop has started its next iteration (for |
|
|
523 | example, first you C<fork>, then the new child process might exit, and |
|
|
524 | only then do you install a child watcher in the parent for the new pid). |
365 | |
525 | |
|
|
526 | You can access both exit (or tracing) status and pid by using the |
|
|
527 | C<rstatus> and C<rpid> methods on the watcher object. |
|
|
528 | |
366 | You can have as many pid watchers per pid as you want. |
529 | You can have as many pid watchers per pid as you want, they will all be |
|
|
530 | called. |
367 | |
531 | |
368 | The C<child_ns> variant doesn't start (activate) the newly created watcher. |
532 | The C<child_ns> variant doesn't start (activate) the newly created watcher. |
369 | |
533 | |
370 | =item $w->set ($pid) |
534 | =item $w->set ($pid) |
371 | |
535 | |
372 | Reconfigures the watcher, see the constructor above for details. Can be at |
536 | Reconfigures the watcher, see the constructor above for details. Can be called at |
373 | any time. |
537 | any time. |
374 | |
538 | |
375 | =item $current_pid = $w->pid |
539 | =item $current_pid = $w->pid |
376 | |
540 | |
377 | =item $old_pid = $w->pid ($new_pid) |
541 | =item $old_pid = $w->pid ($new_pid) |
… | |
… | |
386 | =item $pid = $w->rpid |
550 | =item $pid = $w->rpid |
387 | |
551 | |
388 | Return the pid of the awaited child (useful when you have installed a |
552 | Return the pid of the awaited child (useful when you have installed a |
389 | watcher for all pids). |
553 | watcher for all pids). |
390 | |
554 | |
|
|
555 | =back |
|
|
556 | |
|
|
557 | |
|
|
558 | =head3 STAT WATCHERS - did the file attributes just change? |
|
|
559 | |
|
|
560 | =over 4 |
|
|
561 | |
|
|
562 | =item $w = EV::stat $path, $interval, $callback |
|
|
563 | |
|
|
564 | =item $w = EV::stat_ns $path, $interval, $callback |
|
|
565 | |
|
|
566 | Call the callback when a file status change has been detected on |
|
|
567 | C<$path>. The C<$path> does not need to exist, changing from "path exists" |
|
|
568 | to "path does not exist" is a status change like any other. |
|
|
569 | |
|
|
570 | The C<$interval> is a recommended polling interval for systems where |
|
|
571 | OS-supported change notifications don't exist or are not supported. If |
|
|
572 | you use C<0> then an unspecified default is used (which is highly |
|
|
573 | recommended!), which is to be expected to be around five seconds usually. |
|
|
574 | |
|
|
575 | This watcher type is not meant for massive numbers of stat watchers, |
|
|
576 | as even with OS-supported change notifications, this can be |
|
|
577 | resource-intensive. |
|
|
578 | |
|
|
579 | The C<stat_ns> variant doesn't start (activate) the newly created watcher. |
|
|
580 | |
|
|
581 | =item $w->set ($path, $interval) |
|
|
582 | |
|
|
583 | Reconfigures the watcher, see the constructor above for details. Can be |
|
|
584 | called at any time. |
|
|
585 | |
|
|
586 | =item $current_path = $w->path |
|
|
587 | |
|
|
588 | =item $old_path = $w->path ($new_path) |
|
|
589 | |
|
|
590 | Returns the previously set path and optionally set a new one. |
|
|
591 | |
|
|
592 | =item $current_interval = $w->interval |
|
|
593 | |
|
|
594 | =item $old_interval = $w->interval ($new_interval) |
|
|
595 | |
|
|
596 | Returns the previously set interval and optionally set a new one. Can be |
|
|
597 | used to query the actual interval used. |
|
|
598 | |
|
|
599 | =back |
|
|
600 | |
|
|
601 | |
|
|
602 | =head3 IDLE WATCHERS - when you've got nothing better to do... |
|
|
603 | |
|
|
604 | =over 4 |
391 | |
605 | |
392 | =item $w = EV::idle $callback |
606 | =item $w = EV::idle $callback |
393 | |
607 | |
394 | =item $w = EV::idle_ns $callback |
608 | =item $w = EV::idle_ns $callback |
395 | |
609 | |
… | |
… | |
399 | The process will not block as long as any idle watchers are active, and |
613 | The process will not block as long as any idle watchers are active, and |
400 | they will be called repeatedly until stopped. |
614 | they will be called repeatedly until stopped. |
401 | |
615 | |
402 | The C<idle_ns> variant doesn't start (activate) the newly created watcher. |
616 | The C<idle_ns> variant doesn't start (activate) the newly created watcher. |
403 | |
617 | |
|
|
618 | =back |
|
|
619 | |
|
|
620 | |
|
|
621 | =head3 PREPARE WATCHERS - customise your event loop! |
|
|
622 | |
|
|
623 | =over 4 |
404 | |
624 | |
405 | =item $w = EV::prepare $callback |
625 | =item $w = EV::prepare $callback |
406 | |
626 | |
407 | =item $w = EV::prepare_ns $callback |
627 | =item $w = EV::prepare_ns $callback |
408 | |
628 | |
… | |
… | |
411 | |
631 | |
412 | See the EV::check watcher, below, for explanations and an example. |
632 | See the EV::check watcher, below, for explanations and an example. |
413 | |
633 | |
414 | The C<prepare_ns> variant doesn't start (activate) the newly created watcher. |
634 | The C<prepare_ns> variant doesn't start (activate) the newly created watcher. |
415 | |
635 | |
|
|
636 | =back |
|
|
637 | |
|
|
638 | |
|
|
639 | =head3 CHECK WATCHERS - customise your event loop even more! |
|
|
640 | |
|
|
641 | =over 4 |
416 | |
642 | |
417 | =item $w = EV::check $callback |
643 | =item $w = EV::check $callback |
418 | |
644 | |
419 | =item $w = EV::check_ns $callback |
645 | =item $w = EV::check_ns $callback |
420 | |
646 | |
… | |
… | |
432 | # do nothing unless active |
658 | # do nothing unless active |
433 | $dispatcher->{_event_queue_h} |
659 | $dispatcher->{_event_queue_h} |
434 | or return; |
660 | or return; |
435 | |
661 | |
436 | # make the dispatcher handle any outstanding stuff |
662 | # make the dispatcher handle any outstanding stuff |
|
|
663 | ... not shown |
437 | |
664 | |
438 | # create an IO watcher for each and every socket |
665 | # create an IO watcher for each and every socket |
439 | @snmp_watcher = ( |
666 | @snmp_watcher = ( |
440 | (map { EV::io $_, EV::READ, sub { } } |
667 | (map { EV::io $_, EV::READ, sub { } } |
441 | keys %{ $dispatcher->{_descriptors} }), |
668 | keys %{ $dispatcher->{_descriptors} }), |
|
|
669 | |
|
|
670 | EV::timer +($event->[Net::SNMP::Dispatcher::_ACTIVE] |
|
|
671 | ? $event->[Net::SNMP::Dispatcher::_TIME] - EV::now : 0), |
|
|
672 | 0, sub { }, |
442 | ); |
673 | ); |
443 | |
|
|
444 | # if there are any timeouts, also create a timer |
|
|
445 | push @snmp_watcher, EV::timer $event->[Net::SNMP::Dispatcher::_TIME] - EV::now, 0, sub { } |
|
|
446 | if $event->[Net::SNMP::Dispatcher::_ACTIVE]; |
|
|
447 | }; |
674 | }; |
448 | |
675 | |
449 | The callbacks are irrelevant, the only purpose of those watchers is |
676 | The callbacks are irrelevant (and are not even being called), the |
450 | to wake up the process as soon as one of those events occurs (socket |
677 | only purpose of those watchers is to wake up the process as soon as |
451 | readable, or timer timed out). The corresponding EV::check watcher will then |
678 | one of those events occurs (socket readable, or timer timed out). The |
452 | clean up: |
679 | corresponding EV::check watcher will then clean up: |
453 | |
680 | |
454 | our $snmp_check = EV::check sub { |
681 | our $snmp_check = EV::check sub { |
455 | # destroy all watchers |
682 | # destroy all watchers |
456 | @snmp_watcher = (); |
683 | @snmp_watcher = (); |
457 | |
684 | |
458 | # make the dispatcher handle any new stuff |
685 | # make the dispatcher handle any new stuff |
|
|
686 | ... not shown |
459 | }; |
687 | }; |
460 | |
688 | |
461 | The callbacks of the created watchers will not be called as the watchers |
689 | The callbacks of the created watchers will not be called as the watchers |
462 | are destroyed before this cna happen (remember EV::check gets called |
690 | are destroyed before this cna happen (remember EV::check gets called |
463 | first). |
691 | first). |
464 | |
692 | |
465 | The C<check_ns> variant doesn't start (activate) the newly created watcher. |
693 | The C<check_ns> variant doesn't start (activate) the newly created watcher. |
466 | |
694 | |
467 | =back |
695 | =back |
468 | |
696 | |
|
|
697 | |
|
|
698 | =head3 FORK WATCHERS - the audacity to resume the event loop after a fork |
|
|
699 | |
|
|
700 | Fork watchers are called when a C<fork ()> was detected. The invocation |
|
|
701 | is done before the event loop blocks next and before C<check> watchers |
|
|
702 | are being called, and only in the child after the fork. |
|
|
703 | |
|
|
704 | =over 4 |
|
|
705 | |
|
|
706 | =item $w = EV::fork $callback |
|
|
707 | |
|
|
708 | =item $w = EV::fork_ns $callback |
|
|
709 | |
|
|
710 | Call the callback before the event loop is resumed in the child process |
|
|
711 | after a fork. |
|
|
712 | |
|
|
713 | The C<fork_ns> variant doesn't start (activate) the newly created watcher. |
|
|
714 | |
|
|
715 | =back |
|
|
716 | |
|
|
717 | |
469 | =head1 THREADS |
718 | =head1 THREADS |
470 | |
719 | |
471 | Threads are not supported by this in any way. Perl pseudo-threads is evil |
720 | Threads are not supported by this module in any way. Perl pseudo-threads |
472 | stuff and must die. |
721 | is evil stuff and must die. As soon as Perl gains real threads I will work |
|
|
722 | on thread support for it. |
|
|
723 | |
|
|
724 | =head1 FORK |
|
|
725 | |
|
|
726 | Most of the "improved" event delivering mechanisms of modern operating |
|
|
727 | systems have quite a few problems with fork(2) (to put it bluntly: it is |
|
|
728 | not supported and usually destructive). Libev makes it possible to work |
|
|
729 | around this by having a function that recreates the kernel state after |
|
|
730 | fork in the child. |
|
|
731 | |
|
|
732 | On non-win32 platforms, this module requires the pthread_atfork |
|
|
733 | functionality to do this automatically for you. This function is quite |
|
|
734 | buggy on most BSDs, though, so YMMV. The overhead for this is quite |
|
|
735 | negligible, because everything the function currently does is set a flag |
|
|
736 | that is checked only when the event loop gets used the next time, so when |
|
|
737 | you do fork but not use EV, the overhead is minimal. |
|
|
738 | |
|
|
739 | On win32, there is no notion of fork so all this doesn't apply, of course. |
473 | |
740 | |
474 | =cut |
741 | =cut |
475 | |
742 | |
476 | our $DIED = sub { |
743 | our $DIED = sub { |
477 | warn "EV: error in callback (ignoring): $@"; |
744 | warn "EV: error in callback (ignoring): $@"; |
478 | }; |
745 | }; |
479 | |
746 | |
480 | init |
747 | default_loop |
481 | or die 'EV: cannot initialise libev backend. bad $ENV{LIBEV_METHODS}?'; |
748 | or die 'EV: cannot initialise libev backend. bad $ENV{LIBEV_METHODS}?'; |
482 | |
749 | |
483 | push @AnyEvent::REGISTRY, [EV => "EV::AnyEvent"]; |
|
|
484 | |
|
|
485 | 1; |
750 | 1; |
486 | |
751 | |
487 | =head1 SEE ALSO |
752 | =head1 SEE ALSO |
488 | |
753 | |
489 | L<EV::DNS>, L<EV::AnyEvent>. |
754 | L<EV::DNS>. |
490 | |
755 | |
491 | =head1 AUTHOR |
756 | =head1 AUTHOR |
492 | |
757 | |
493 | Marc Lehmann <schmorp@schmorp.de> |
758 | Marc Lehmann <schmorp@schmorp.de> |
494 | http://home.schmorp.de/ |
759 | http://home.schmorp.de/ |