… | |
… | |
207 | |
207 | |
208 | There are two ways to handle timers: based on real time (relative, "fire |
208 | There are two ways to handle timers: based on real time (relative, "fire |
209 | in 10 seconds") and based on wallclock time (absolute, "fire at 12 |
209 | in 10 seconds") and based on wallclock time (absolute, "fire at 12 |
210 | o'clock"). |
210 | o'clock"). |
211 | |
211 | |
212 | While most event loops expect timers to specified in a relative way, they use |
212 | While most event loops expect timers to specified in a relative way, they |
213 | absolute time internally. This makes a difference when your clock "jumps", |
213 | use absolute time internally. This makes a difference when your clock |
214 | for example, when ntp decides to set your clock backwards from the wrong 2014-01-01 to |
214 | "jumps", for example, when ntp decides to set your clock backwards from |
215 | 2008-01-01, a watcher that you created to fire "after" a second might actually take |
215 | the wrong date of 2014-01-01 to 2008-01-01, a watcher that is supposed to |
216 | six years to finally fire. |
216 | fire "after" a second might actually take six years to finally fire. |
217 | |
217 | |
218 | AnyEvent cannot compensate for this. The only event loop that is conscious |
218 | AnyEvent cannot compensate for this. The only event loop that is conscious |
219 | about these issues is L<EV>, which offers both relative (ev_timer) and |
219 | about these issues is L<EV>, which offers both relative (ev_timer, based |
220 | absolute (ev_periodic) timers. |
220 | on true relative time) and absolute (ev_periodic, based on wallclock time) |
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221 | timers. |
221 | |
222 | |
222 | AnyEvent always prefers relative timers, if available, matching the |
223 | AnyEvent always prefers relative timers, if available, matching the |
223 | AnyEvent API. |
224 | AnyEvent API. |
224 | |
225 | |
225 | =head2 SIGNAL WATCHERS |
226 | =head2 SIGNAL WATCHERS |
226 | |
227 | |
227 | You can watch for signals using a signal watcher, C<signal> is the signal |
228 | You can watch for signals using a signal watcher, C<signal> is the signal |
228 | I<name> without any C<SIG> prefix, C<cb> is the Perl callback to |
229 | I<name> without any C<SIG> prefix, C<cb> is the Perl callback to |
229 | be invoked whenever a signal occurs. |
230 | be invoked whenever a signal occurs. |
230 | |
231 | |
231 | Multiple signals occurances can be clumped together into one callback |
232 | Multiple signal occurances can be clumped together into one callback |
232 | invocation, and callback invocation will be synchronous. synchronous means |
233 | invocation, and callback invocation will be synchronous. synchronous means |
233 | that it might take a while until the signal gets handled by the process, |
234 | that it might take a while until the signal gets handled by the process, |
234 | but it is guarenteed not to interrupt any other callbacks. |
235 | but it is guarenteed not to interrupt any other callbacks. |
235 | |
236 | |
236 | The main advantage of using these watchers is that you can share a signal |
237 | The main advantage of using these watchers is that you can share a signal |
… | |
… | |
421 | no warnings; |
422 | no warnings; |
422 | use strict; |
423 | use strict; |
423 | |
424 | |
424 | use Carp; |
425 | use Carp; |
425 | |
426 | |
426 | our $VERSION = '3.12'; |
427 | our $VERSION = '3.2'; |
427 | our $MODEL; |
428 | our $MODEL; |
428 | |
429 | |
429 | our $AUTOLOAD; |
430 | our $AUTOLOAD; |
430 | our @ISA; |
431 | our @ISA; |
431 | |
432 | |
… | |
… | |
456 | if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) { |
457 | if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) { |
457 | my $model = "AnyEvent::Impl::$1"; |
458 | my $model = "AnyEvent::Impl::$1"; |
458 | if (eval "require $model") { |
459 | if (eval "require $model") { |
459 | $MODEL = $model; |
460 | $MODEL = $model; |
460 | warn "AnyEvent: loaded model '$model' (forced by \$PERL_ANYEVENT_MODEL), using it.\n" if $verbose > 1; |
461 | warn "AnyEvent: loaded model '$model' (forced by \$PERL_ANYEVENT_MODEL), using it.\n" if $verbose > 1; |
|
|
462 | } else { |
|
|
463 | warn "AnyEvent: unable to load model '$model' (from \$PERL_ANYEVENT_MODEL):\n$@" if $verbose; |
461 | } |
464 | } |
462 | } |
465 | } |
463 | |
466 | |
464 | # check for already loaded models |
467 | # check for already loaded models |
465 | unless ($MODEL) { |
468 | unless ($MODEL) { |
… | |
… | |
658 | |
661 | |
659 | =over 4 |
662 | =over 4 |
660 | |
663 | |
661 | =item C<PERL_ANYEVENT_VERBOSE> |
664 | =item C<PERL_ANYEVENT_VERBOSE> |
662 | |
665 | |
|
|
666 | By default, AnyEvent will be completely silent except in fatal |
|
|
667 | conditions. You can set this environment variable to make AnyEvent more |
|
|
668 | talkative. |
|
|
669 | |
|
|
670 | When set to C<1> or higher, causes AnyEvent to warn about unexpected |
|
|
671 | conditions, such as not being able to load the event model specified by |
|
|
672 | C<PERL_ANYEVENT_MODEL>. |
|
|
673 | |
663 | When set to C<2> or higher, cause AnyEvent to report to STDERR which event |
674 | When set to C<2> or higher, cause AnyEvent to report to STDERR which event |
664 | model it chooses. |
675 | model it chooses. |
665 | |
676 | |
666 | =item C<PERL_ANYEVENT_MODEL> |
677 | =item C<PERL_ANYEVENT_MODEL> |
667 | |
678 | |