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Comparing EV/EV.pm (file contents):
Revision 1.27 by root, Sat Nov 3 09:19:58 2007 UTC vs.
Revision 1.36 by root, Sun Nov 11 04:14:09 2007 UTC

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 };
49 44
50 # MAINLOOP 45 # MAINLOOP
51 EV::loop; # loop until EV::loop_done is called 46 EV::loop; # loop until EV::loop_done is called or all watchers stop
52 EV::loop EV::LOOP_ONESHOT; # block until at least one event could be handled 47 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 48 EV::loop EV::LOOP_NONBLOCK; # try to handle same events, but do not block
54 49
55=head1 DESCRIPTION 50=head1 DESCRIPTION
56 51
62package EV; 57package EV;
63 58
64use strict; 59use strict;
65 60
66BEGIN { 61BEGIN {
67 our $VERSION = '0.5'; 62 our $VERSION = '0.8';
68 use XSLoader; 63 use XSLoader;
69 XSLoader::load "EV", $VERSION; 64 XSLoader::load "EV", $VERSION;
70} 65}
71 66
72@EV::Io::ISA = 67@EV::Io::ISA =
186 181
187=item $bool = $w->is_active 182=item $bool = $w->is_active
188 183
189Returns true if the watcher is active, false otherwise. 184Returns true if the watcher is active, false otherwise.
190 185
186=item $current_data = $w->data
187
188=item $old_data = $w->data ($new_data)
189
190Queries a freely usable data scalar on the watcher and optionally changes
191it. This is a way to associate custom data with a watcher:
192
193 my $w = EV::timer 60, 0, sub {
194 warn $_[0]->data;
195 };
196 $w->data ("print me!");
197
191=item $current_cb = $w->cb 198=item $current_cb = $w->cb
192 199
193=item $old_cb = $w->cb ($new_cb) 200=item $old_cb = $w->cb ($new_cb)
194 201
195Queries the callback on the watcher and optionally changes it. You can do 202Queries the callback on the watcher and optionally changes it. You can do
285operation. You create a timer object with the same value for C<$after> and 292operation. You create a timer object with the same value for C<$after> and
286C<$repeat>, and then, in the read/write watcher, run the C<again> method 293C<$repeat>, and then, in the read/write watcher, run the C<again> method
287on the timeout. 294on the timeout.
288 295
289 296
290=item $w = EV::periodic $at, $interval, $callback 297=item $w = EV::periodic $at, $interval, $reschedule_cb, $callback
291 298
292=item $w = EV::periodic_ns $at, $interval, $callback 299=item $w = EV::periodic_ns $at, $interval, $reschedule_cb, $callback
293 300
294Similar to EV::timer, but the time is given as an absolute point in time 301Similar to EV::timer, but is not based on relative timeouts but on
295(C<$at>), plus an optional C<$interval>. 302absolute times. Apart from creating "simple" timers that trigger "at" the
303specified time, it can also be used for non-drifting absolute timers and
304more complex, cron-like, setups that are not adversely affected by time
305jumps (i.e. when the system clock is changed by explicit date -s or other
306means such as ntpd). It is also the most complex watcher type in EV.
296 307
297If the C<$interval> is zero, then the callback will be called at the time 308It has three distinct "modes":
298C<$at> if that is in the future, or as soon as possible if it is in the
299past. It will not automatically repeat.
300 309
301If the C<$interval> is nonzero, then the watcher will always be scheduled 310=over 4
302to time out at the next C<$at + N * $interval> time.
303 311
304This can be used to schedule a callback to run at very regular intervals, 312=item * absolute timer ($interval = $reschedule_cb = 0)
305as long as the processing time is less then the interval (otherwise 313
306obviously events will be skipped). 314This time simply fires at the wallclock time C<$at> and doesn't repeat. It
315will not adjust when a time jump occurs, that is, if it is to be run
316at January 1st 2011 then it will run when the system time reaches or
317surpasses this time.
318
319=item * non-repeating interval timer ($interval > 0, $reschedule_cb = 0)
320
321In this mode the watcher will always be scheduled to time out at the
322next C<$at + N * $interval> time (for some integer N) and then repeat,
323regardless of any time jumps.
324
325This can be used to create timers that do not drift with respect to system
326time:
327
328 my $hourly = EV::periodic 0, 3600, 0, sub { print "once/hour\n" };
329
330That doesn't mean there will always be 3600 seconds in between triggers,
331but only that the the clalback will be called when the system time shows a
332full hour (UTC).
307 333
308Another way to think about it (for the mathematically inclined) is that 334Another way to think about it (for the mathematically inclined) is that
309EV::periodic will try to run the callback at the next possible time where 335EV::periodic will try to run the callback in this mode at the next
310C<$time = $at (mod $interval)>, regardless of any time jumps. 336possible time where C<$time = $at (mod $interval)>, regardless of any time
337jumps.
311 338
312This periodic timer is based on "wallclock time", that is, if the clock 339=item * manual reschedule mode ($reschedule_cb = coderef)
313changes (C<ntp>, C<date -s> etc.), then the timer will nevertheless run at 340
314the specified time. This means it will never drift (it might jitter, but 341In this mode $interval and $at are both being ignored. Instead, each time
315it will not drift). 342the periodic watcher gets scheduled, the first callback ($reschedule_cb)
343will be called with the watcher as first, and the current time as second
344argument.
345
346I<This callback MUST NOT stop or destroy this or any other periodic
347watcher, ever>. If you need to stop it, return 1e30 and stop it
348afterwards.
349
350It must return the next time to trigger, based on the passed time value
351(that is, the lowest time value larger than to the second argument). It
352will usually be called just before the callback will be triggered, but
353might be called at other times, too.
354
355This can be used to create very complex timers, such as a timer that
356triggers on each midnight, local time (actually 24 hours after the last
357midnight, to keep the example simple. If you know a way to do it correctly
358in about the same space (without requiring elaborate modules), drop me a
359note :):
360
361 my $daily = EV::periodic 0, 0, sub {
362 my ($w, $now) = @_;
363
364 use Time::Local ();
365 my (undef, undef, undef, $d, $m, $y) = localtime $now;
366 86400 + Time::Local::timelocal 0, 0, 0, $d, $m, $y
367 }, sub {
368 print "it's midnight or likely shortly after, now\n";
369 };
370
371=back
316 372
317The C<periodic_ns> variant doesn't start (activate) the newly created watcher. 373The C<periodic_ns> variant doesn't start (activate) the newly created watcher.
318 374
319=item $w->set ($at, $interval) 375=item $w->set ($at, $interval, $reschedule_cb)
320 376
321Reconfigures the watcher, see the constructor above for details. Can be at 377Reconfigures the watcher, see the constructor above for details. Can be at
322any time. 378any time.
379
380=item $w->again
381
382Simply stops and starts the watcher again.
323 383
324 384
325=item $w = EV::signal $signal, $callback 385=item $w = EV::signal $signal, $callback
326 386
327=item $w = EV::signal_ns $signal, $callback 387=item $w = EV::signal_ns $signal, $callback
475 535
476our $DIED = sub { 536our $DIED = sub {
477 warn "EV: error in callback (ignoring): $@"; 537 warn "EV: error in callback (ignoring): $@";
478}; 538};
479 539
480init 540default_loop
481 or die 'EV: cannot initialise libev backend. bad $ENV{LIBEV_METHODS}?'; 541 or die 'EV: cannot initialise libev backend. bad $ENV{LIBEV_METHODS}?';
482
483push @AnyEvent::REGISTRY, [EV => "EV::AnyEvent"];
484 542
4851; 5431;
486 544
487=head1 SEE ALSO 545=head1 SEE ALSO
488 546

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