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Revision 1.6 by root, Thu Nov 1 17:32:39 2007 UTC vs.
Revision 1.12 by root, Tue Nov 27 07:27:10 2007 UTC

… …
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, 1, sub { 14 my $w = EV::timer 2, 2, sub {
15 warn "is called roughly every 2s (repeat = 1)"; 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, 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, $revents) = @_; # all callbacks get the watcher object and event mask 27 my ($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 my $w = EV::signal 3, sub {
38 warn "sigquit received (this is GNU/Linux, right?)\n";
39 };
40
41 # CHILD/PID STATUS CHANGES 37 # CHILD/PID STATUS CHANGES
42 38
43 my $w = EV::child 666, sub { 39 my $w = EV::child 666, sub {
44 my ($w, $revents, $status) = @_; 40 my ($w, $revents) = @_;
41 my $status = $w->rstatus;
45 }; 42 };
46 43
47 # MAINLOOP 44 # MAINLOOP
48 EV::loop; # loop until EV::loop_done is called 45 EV::loop; # loop until EV::unloop is called or all watchers stop
49 EV::loop EV::LOOP_ONESHOT; # block until at least one event could be handled 46 EV::loop EV::LOOP_ONESHOT; # block until at least one event could be handled
50 EV::loop EV::LOOP_NONBLOCK; # try to handle same events, but do not block 47 EV::loop EV::LOOP_NONBLOCK; # try to handle same events, but do not block
51 48
52DESCRIPTION 49DESCRIPTION
53 This module provides an interface to libev 50 This module provides an interface to libev
54 (<http://software.schmorp.de/pkg/libev.html>). 51 (<http://software.schmorp.de/pkg/libev.html>). While the documentation
52 below is comprehensive, one might also consult the documentation of
53 libev itself (<http://cvs.schmorp.de/libev/ev.html>) for more subtle
54 details on watcher semantics or some discussion on the available
55 backends, or how to force a specific backend with "LIBEV_FLAGS".
55 56
56BASIC INTERFACE 57BASIC INTERFACE
57 $EV::DIED 58 $EV::DIED
58 Must contain a reference to a function that is called when a 59 Must contain a reference to a function that is called when a
59 callback throws an exception (with $@ containing thr error). The 60 callback throws an exception (with $@ containing thr error). The
… …
67 $time = EV::now 68 $time = EV::now
68 Returns the time the last event loop iteration has been started. 69 Returns the time the last event loop iteration has been started.
69 This is the time that (relative) timers are based on, and refering 70 This is the time that (relative) timers are based on, and refering
70 to it is usually faster then calling EV::time. 71 to it is usually faster then calling EV::time.
71 72
72 $method = EV::ev_method 73 $method = EV::method
73 Returns an integer describing the backend used by libev 74 Returns an integer describing the backend used by libev
74 (EV::METHOD_SELECT or EV::METHOD_EPOLL). 75 (EV::METHOD_SELECT or EV::METHOD_EPOLL).
75 76
76 EV::loop [$flags] 77 EV::loop [$flags]
77 Begin checking for events and calling callbacks. It returns when a 78 Begin checking for events and calling callbacks. It returns when a
78 callback calls EV::loop_done. 79 callback calls EV::unloop.
79 80
80 The $flags argument can be one of the following: 81 The $flags argument can be one of the following:
81 82
82 0 as above 83 0 as above
83 EV::LOOP_ONESHOT block at most once (wait, but do not loop) 84 EV::LOOP_ONESHOT block at most once (wait, but do not loop)
84 EV::LOOP_NONBLOCK do not block at all (fetch/handle events but do not wait) 85 EV::LOOP_NONBLOCK do not block at all (fetch/handle events but do not wait)
85 86
86 EV::loop_done [$how] 87 EV::unloop [$how]
87 When called with no arguments or an argument of 1, makes the 88 When called with no arguments or an argument of EV::UNLOOP_ONE,
88 innermost call to EV::loop return. 89 makes the innermost call to EV::loop return.
89 90
90 When called with an agrument of 2, all calls to EV::loop will return 91 When called with an argument of EV::UNLOOP_ALL, all calls to
91 as fast as possible. 92 EV::loop will return as fast as possible.
93
94 EV::once $fh_or_undef, $events, $timeout, $cb->($revents)
95 This function rolls together an I/O and a timer watcher for a single
96 one-shot event without the need for managing a watcher object.
97
98 If $fh_or_undef is a filehandle or file descriptor, then $events
99 must be a bitset containing either "EV::READ", "EV::WRITE" or
100 "EV::READ | EV::WRITE", indicating the type of I/O event you want to
101 wait for. If you do not want to wait for some I/O event, specify
102 "undef" for $fh_or_undef and 0 for $events).
103
104 If timeout is "undef" or negative, then there will be no timeout.
105 Otherwise a EV::timer with this value will be started.
106
107 When an error occurs or either the timeout or I/O watcher triggers,
108 then the callback will be called with the received event set (in
109 general you can expect it to be a combination of "EV:ERROR",
110 "EV::READ", "EV::WRITE" and "EV::TIMEOUT").
111
112 EV::once doesn't return anything: the watchers stay active till
113 either of them triggers, then they will be stopped and freed, and
114 the callback invoked.
92 115
93 WATCHER 116 WATCHER
94 A watcher is an object that gets created to record your interest in some 117 A watcher is an object that gets created to record your interest in some
95 event. For instance, if you want to wait for STDIN to become readable, 118 event. For instance, if you want to wait for STDIN to become readable,
96 you would create an EV::io watcher for that: 119 you would create an EV::io watcher for that:
… …
115 In the rare case where one wants to create a watcher but not start it at 138 In the rare case where one wants to create a watcher but not start it at
116 the same time, each constructor has a variant with a trailing "_ns" in 139 the same time, each constructor has a variant with a trailing "_ns" in
117 its name, e.g. EV::io has a non-starting variant EV::io_ns and so on. 140 its name, e.g. EV::io has a non-starting variant EV::io_ns and so on.
118 141
119 Please note that a watcher will automatically be stopped when the 142 Please note that a watcher will automatically be stopped when the
120 watcher object is returned, so you *need* to keep the watcher objects 143 watcher object is destroyed, so you *need* to keep the watcher objects
121 returned by the constructors. 144 returned by the constructors.
145
146 Also, all methods changing some aspect of a watcher (->set, ->priority,
147 ->fh and so on) automatically stop and start it again if it is active,
148 which means pending events get lost.
122 149
123 WATCHER TYPES 150 WATCHER TYPES
124 Now lets move to the existing watcher types and asociated methods. 151 Now lets move to the existing watcher types and asociated methods.
125 152
126 The following methods are available for all watchers. Then followes a 153 The following methods are available for all watchers. Then followes a
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141 not. 168 not.
142 169
143 $bool = $w->is_active 170 $bool = $w->is_active
144 Returns true if the watcher is active, false otherwise. 171 Returns true if the watcher is active, false otherwise.
145 172
173 $current_data = $w->data
174 $old_data = $w->data ($new_data)
175 Queries a freely usable data scalar on the watcher and optionally
176 changes it. This is a way to associate custom data with a watcher:
177
178 my $w = EV::timer 60, 0, sub {
179 warn $_[0]->data;
180 };
181 $w->data ("print me!");
182
146 $current_cb = $w->cb 183 $current_cb = $w->cb
147 $old_cb = $w->cb ($new_cb) 184 $old_cb = $w->cb ($new_cb)
148 Queries the callback on the watcher and optionally changes it. You 185 Queries the callback on the watcher and optionally changes it. You
149 cna do this at any time. 186 can do this at any time without the watcher restarting.
187
188 $current_priority = $w->priority
189 $old_priority = $w->priority ($new_priority)
190 Queries the priority on the watcher and optionally changes it.
191 Pending watchers with higher priority will be invoked first. The
192 valid range of priorities lies between EV::MAXPRI (default 2) and
193 EV::MINPRI (default -2). If the priority is outside this range it
194 will automatically be normalised to the nearest valid priority.
195
196 The default priority of any newly-created watcher is 0.
197
198 Note that the priority semantics have not yet been fleshed out and
199 are subject to almost certain change.
150 200
151 $w->trigger ($revents) 201 $w->trigger ($revents)
152 Call the callback *now* with the given event mask. 202 Call the callback *now* with the given event mask.
203
204 $previous_state = $w->keepalive ($bool)
205 Normally, "EV::loop" will return when there are no active watchers
206 (which is a "deadlock" because no progress can be made anymore).
207 This is convinient because it allows you to start your watchers (and
208 your jobs), call "EV::loop" once and when it returns you know that
209 all your jobs are finished (or they forgot to register some watchers
210 for their task :).
211
212 Sometimes, however, this gets in your way, for example when you the
213 module that calls "EV::loop" (usually the main program) is not the
214 same module as a long-living watcher (for example a DNS client
215 module written by somebody else even). Then you might want any
216 outstanding requests to be handled, but you would not want to keep
217 "EV::loop" from returning just because you happen to have this
218 long-running UDP port watcher.
219
220 In this case you can clear the keepalive status, which means that
221 even though your watcher is active, it won't keep "EV::loop" from
222 returning.
223
224 The initial value for keepalive is true (enabled), and you cna
225 change it any time.
226
227 Example: Register an IO watcher for some UDP socket but do not keep
228 the event loop from running just because of that watcher.
229
230 my $udp_socket = ...
231 my $udp_watcher = EV::io $udp_socket, EV::READ, sub { ... };
232 $udp_watcher->keepalive (0);
153 233
154 $w = EV::io $fileno_or_fh, $eventmask, $callback 234 $w = EV::io $fileno_or_fh, $eventmask, $callback
155 $w = EV::io_ns $fileno_or_fh, $eventmask, $callback 235 $w = EV::io_ns $fileno_or_fh, $eventmask, $callback
156 As long as the returned watcher object is alive, call the $callback 236 As long as the returned watcher object is alive, call the $callback
157 when the events specified in $eventmask. 237 when the events specified in $eventmask.
… …
176 $old_eventmask = $w->events ($new_eventmask) 256 $old_eventmask = $w->events ($new_eventmask)
177 Returns the previously set event mask and optionally set a new one. 257 Returns the previously set event mask and optionally set a new one.
178 258
179 $w = EV::timer $after, $repeat, $callback 259 $w = EV::timer $after, $repeat, $callback
180 $w = EV::timer_ns $after, $repeat, $callback 260 $w = EV::timer_ns $after, $repeat, $callback
181 Calls the callback after $after seconds. If $repeat is non-zero, the 261 Calls the callback after $after seconds (which may be fractional).
182 timer will be restarted (with the $repeat value as $after) after the 262 If $repeat is non-zero, the timer will be restarted (with the
183 callback returns. 263 $repeat value as $after) after the callback returns.
184 264
185 This means that the callback would be called roughly after $after 265 This means that the callback would be called roughly after $after
186 seconds, and then every $repeat seconds. "Roughly" because the time 266 seconds, and then every $repeat seconds. The timer does his best not
187 of callback processing is not taken into account, so the timer will 267 to drift, but it will not invoke the timer more often then once per
188 slowly drift. If that isn't acceptable, look at EV::periodic. 268 event loop iteration, and might drift in other cases. If that isn't
269 acceptable, look at EV::periodic, which can provide long-term stable
270 timers.
189 271
190 The timer is based on a monotonic clock, that is if somebody is 272 The timer is based on a monotonic clock, that is, if somebody is
191 sitting in front of the machine while the timer is running and 273 sitting in front of the machine while the timer is running and
192 changes the system clock, the timer will nevertheless run (roughly) 274 changes the system clock, the timer will nevertheless run (roughly)
193 the same time. 275 the same time.
194 276
195 The "timer_ns" variant doesn't start (activate) the newly created 277 The "timer_ns" variant doesn't start (activate) the newly created
… …
201 283
202 $w->again 284 $w->again
203 Similar to the "start" method, but has special semantics for 285 Similar to the "start" method, but has special semantics for
204 repeating timers: 286 repeating timers:
205 287
288 If the timer is active and non-repeating, it will be stopped.
289
206 If the timer is active and repeating, reset the timeout to occur 290 If the timer is active and repeating, reset the timeout to occur
207 $repeat seconds after now. 291 $repeat seconds after now.
208 292
209 If the timer is active and non-repeating, it will be stopped.
210
211 If the timer is in active and repeating, start it. 293 If the timer is inactive and repeating, start it using the repeat
294 value.
212 295
213 Otherwise do nothing. 296 Otherwise do nothing.
214 297
215 This behaviour is useful when you have a timeout for some IO 298 This behaviour is useful when you have a timeout for some IO
216 operation. You create a timer object with the same value for $after 299 operation. You create a timer object with the same value for $after
217 and $repeat, and then, in the read/write watcher, run the "again" 300 and $repeat, and then, in the read/write watcher, run the "again"
218 method on the timeout. 301 method on the timeout.
219 302
220 $w = EV::periodic $at, $interval, $callback 303 $w = EV::periodic $at, $interval, $reschedule_cb, $callback
221 $w = EV::periodic_ns $at, $interval, $callback 304 $w = EV::periodic_ns $at, $interval, $reschedule_cb, $callback
222 Similar to EV::timer, but the time is given as an absolute point in 305 Similar to EV::timer, but is not based on relative timeouts but on
223 time ($at), plus an optional $interval. 306 absolute times. Apart from creating "simple" timers that trigger
307 "at" the specified time, it can also be used for non-drifting
308 absolute timers and more complex, cron-like, setups that are not
309 adversely affected by time jumps (i.e. when the system clock is
310 changed by explicit date -s or other means such as ntpd). It is also
311 the most complex watcher type in EV.
224 312
225 If the $interval is zero, then the callback will be called at the 313 It has three distinct "modes":
226 time $at if that is in the future, or as soon as possible if it is
227 in the past. It will not automatically repeat.
228 314
229 If the $interval is nonzero, then the watcher will always be 315 * absolute timer ($interval = $reschedule_cb = 0)
230 scheduled to time out at the next "$at + N * $interval" time. 316 This time simply fires at the wallclock time $at and doesn't
317 repeat. It will not adjust when a time jump occurs, that is, if
318 it is to be run at January 1st 2011 then it will run when the
319 system time reaches or surpasses this time.
231 320
232 This can be used to schedule a callback to run at very regular 321 * non-repeating interval timer ($interval > 0, $reschedule_cb = 0)
233 intervals, as long as the processing time is less then the interval 322 In this mode the watcher will always be scheduled to time out at
234 (otherwise obviously events will be skipped). 323 the next "$at + N * $interval" time (for some integer N) and
324 then repeat, regardless of any time jumps.
235 325
326 This can be used to create timers that do not drift with respect
327 to system time:
328
329 my $hourly = EV::periodic 0, 3600, 0, sub { print "once/hour\n" };
330
331 That doesn't mean there will always be 3600 seconds in between
332 triggers, but only that the the clalback will be called when the
333 system time shows a full hour (UTC).
334
236 Another way to think about it (for the mathematically inclined) is 335 Another way to think about it (for the mathematically inclined)
237 that EV::periodic will try to run the callback at the next possible 336 is that EV::periodic will try to run the callback in this mode
238 time where "$time = $at (mod $interval)", regardless of any time 337 at the next possible time where "$time = $at (mod $interval)",
239 jumps. 338 regardless of any time jumps.
240 339
241 This periodic timer is based on "wallclock time", that is, if the 340 * manual reschedule mode ($reschedule_cb = coderef)
242 clock changes ("ntp", "date -s" etc.), then the timer will 341 In this mode $interval and $at are both being ignored. Instead,
243 nevertheless run at the specified time. This means it will never 342 each time the periodic watcher gets scheduled, the reschedule
244 drift (it might jitter, but it will not drift). 343 callback ($reschedule_cb) will be called with the watcher as
344 first, and the current time as second argument.
345
346 *This callback MUST NOT stop or destroy this or any other
347 periodic watcher, ever*. If you need to stop it, return 1e30 and
348 stop it afterwards.
349
350 It must return the next time to trigger, based on the passed
351 time value (that is, the lowest time value larger than to the
352 second argument). It will usually be called just before the
353 callback will be triggered, but might be called at other times,
354 too.
355
356 This can be used to create very complex timers, such as a timer
357 that triggers on each midnight, local time (actually 24 hours
358 after the last midnight, to keep the example simple. If you know
359 a way to do it correctly in about the same space (without
360 requiring elaborate modules), drop me a note :):
361
362 my $daily = EV::periodic 0, 0, sub {
363 my ($w, $now) = @_;
364
365 use Time::Local ();
366 my (undef, undef, undef, $d, $m, $y) = localtime $now;
367 86400 + Time::Local::timelocal 0, 0, 0, $d, $m, $y
368 }, sub {
369 print "it's midnight or likely shortly after, now\n";
370 };
245 371
246 The "periodic_ns" variant doesn't start (activate) the newly created 372 The "periodic_ns" variant doesn't start (activate) the newly created
247 watcher. 373 watcher.
248 374
249 $w->set ($at, $interval) 375 $w->set ($at, $interval, $reschedule_cb)
250 Reconfigures the watcher, see the constructor above for details. Can 376 Reconfigures the watcher, see the constructor above for details. Can
251 be at any time. 377 be at any time.
378
379 $w->again
380 Simply stops and starts the watcher again.
252 381
253 $w = EV::signal $signal, $callback 382 $w = EV::signal $signal, $callback
254 $w = EV::signal_ns $signal, $callback 383 $w = EV::signal_ns $signal, $callback
255 Call the callback when $signal is received (the signal can be 384 Call the callback when $signal is received (the signal can be
256 specified by number or by name, just as with kill or %SIG). 385 specified by number or by name, just as with kill or %SIG).
… …
266 watcher. 395 watcher.
267 396
268 $w->set ($signal) 397 $w->set ($signal)
269 Reconfigures the watcher, see the constructor above for details. Can 398 Reconfigures the watcher, see the constructor above for details. Can
270 be at any time. 399 be at any time.
400
401 $current_signum = $w->signal
402 $old_signum = $w->signal ($new_signal)
403 Returns the previously set signal (always as a number not name) and
404 optionally set a new one.
271 405
272 $w = EV::child $pid, $callback 406 $w = EV::child $pid, $callback
273 $w = EV::child_ns $pid, $callback 407 $w = EV::child_ns $pid, $callback
274 Call the callback when a status change for pid $pid (or any pid if 408 Call the callback when a status change for pid $pid (or any pid if
275 $pid is 0) has been received. More precisely: when the process 409 $pid is 0) has been received. More precisely: when the process
276 receives a SIGCHLD, EV will fetch the outstanding exit/wait status 410 receives a SIGCHLD, EV will fetch the outstanding exit/wait status
277 for all changed/zombie children and call the callback. 411 for all changed/zombie children and call the callback.
278 412
279 Unlike all other callbacks, this callback will be called with an 413 You can access both status and pid by using the "rstatus" and "rpid"
280 additional third argument which is the exit status. See the 414 methods on the watcher object.
281 "waitpid" function for details.
282 415
283 You can have as many pid watchers per pid as you want. 416 You can have as many pid watchers per pid as you want.
284 417
285 The "child_ns" variant doesn't start (activate) the newly created 418 The "child_ns" variant doesn't start (activate) the newly created
286 watcher. 419 watcher.
287 420
288 $w->set ($pid) 421 $w->set ($pid)
289 Reconfigures the watcher, see the constructor above for details. Can 422 Reconfigures the watcher, see the constructor above for details. Can
290 be at any time. 423 be at any time.
424
425 $current_pid = $w->pid
426 $old_pid = $w->pid ($new_pid)
427 Returns the previously set process id and optionally set a new one.
428
429 $exit_status = $w->rstatus
430 Return the exit/wait status (as returned by waitpid, see the waitpid
431 entry in perlfunc).
432
433 $pid = $w->rpid
434 Return the pid of the awaited child (useful when you have installed
435 a watcher for all pids).
291 436
292 $w = EV::idle $callback 437 $w = EV::idle $callback
293 $w = EV::idle_ns $callback 438 $w = EV::idle_ns $callback
294 Call the callback when there are no pending io, timer/periodic, 439 Call the callback when there are no pending io, timer/periodic,
295 signal or child events, i.e. when the process is idle. 440 signal or child events, i.e. when the process is idle.
… …
328 # do nothing unless active 473 # do nothing unless active
329 $dispatcher->{_event_queue_h} 474 $dispatcher->{_event_queue_h}
330 or return; 475 or return;
331 476
332 # make the dispatcher handle any outstanding stuff 477 # make the dispatcher handle any outstanding stuff
478 ... not shown
333 479
334 # create an IO watcher for each and every socket 480 # create an IO watcher for each and every socket
335 @snmp_watcher = ( 481 @snmp_watcher = (
336 (map { EV::io $_, EV::READ, sub { } } 482 (map { EV::io $_, EV::READ, sub { } }
337 keys %{ $dispatcher->{_descriptors} }), 483 keys %{ $dispatcher->{_descriptors} }),
484
485 EV::timer +($event->[Net::SNMP::Dispatcher::_ACTIVE]
486 ? $event->[Net::SNMP::Dispatcher::_TIME] - EV::now : 0),
487 0, sub { },
338 ); 488 );
339
340 # if there are any timeouts, also create a timer
341 push @snmp_watcher, EV::timer $event->[Net::SNMP::Dispatcher::_TIME] - EV::now, 0, sub { }
342 if $event->[Net::SNMP::Dispatcher::_ACTIVE];
343 }; 489 };
344 490
345 The callbacks are irrelevant, the only purpose of those watchers is 491 The callbacks are irrelevant (and are not even being called), the
346 to wake up the process as soon as one of those events occurs (socket 492 only purpose of those watchers is to wake up the process as soon as
347 readable, or timer timed out). The corresponding EV::check watcher 493 one of those events occurs (socket readable, or timer timed out).
348 will then clean up: 494 The corresponding EV::check watcher will then clean up:
349 495
350 our $snmp_check = EV::check sub { 496 our $snmp_check = EV::check sub {
351 # destroy all watchers 497 # destroy all watchers
352 @snmp_watcher = (); 498 @snmp_watcher = ();
353 499
354 # make the dispatcher handle any new stuff 500 # make the dispatcher handle any new stuff
501 ... not shown
355 }; 502 };
356 503
357 The callbacks of the created watchers will not be called as the 504 The callbacks of the created watchers will not be called as the
358 watchers are destroyed before this cna happen (remember EV::check 505 watchers are destroyed before this cna happen (remember EV::check
359 gets called first). 506 gets called first).
360 507
361 The "check_ns" variant doesn't start (activate) the newly created 508 The "check_ns" variant doesn't start (activate) the newly created
362 watcher. 509 watcher.
363 510
364THREADS 511THREADS
365 Threads are not supported by this in any way. Perl pseudo-threads is 512 Threads are not supported by this module in any way. Perl pseudo-threads
366 evil stuff and must die. 513 is evil stuff and must die. As soon as Perl gains real threads I will
514 work on thread support for it.
515
516FORK
517 Most of the "improved" event delivering mechanisms of modern operating
518 systems have quite a few problems with fork(2) (to put it bluntly: it is
519 not supported and usually destructive). Libev makes it possible to work
520 around this by having a function that recreates the kernel state after
521 fork in the child.
522
523 On non-win32 platforms, this module requires the pthread_atfork
524 functionality to do this automatically for you. This function is quite
525 buggy on most BSDs, though, so YMMV. The overhead for this is quite
526 negligible, because everything the function currently does is set a flag
527 that is checked only when the event loop gets used the next time, so
528 when you do fork but not use EV, the overhead is minimal.
529
530 On win32, there is no notion of fork so all this doesn't apply, of
531 course.
367 532
368SEE ALSO 533SEE ALSO
369 L<EV::DNS>, L<EV::AnyEvent>. 534 L<EV::DNS>.
370 535
371AUTHOR 536AUTHOR
372 Marc Lehmann <schmorp@schmorp.de> 537 Marc Lehmann <schmorp@schmorp.de>
373 http://home.schmorp.de/ 538 http://home.schmorp.de/
374 539

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