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Revision 1.143 by root, Wed May 28 23:57:38 2008 UTC vs.
Revision 1.149 by root, Sat May 31 01:41:22 2008 UTC

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17 }); 17 });
18 18
19 my $w = AnyEvent->condvar; # stores whether a condition was flagged 19 my $w = AnyEvent->condvar; # stores whether a condition was flagged
20 $w->send; # wake up current and all future recv's 20 $w->send; # wake up current and all future recv's
21 $w->recv; # enters "main loop" till $condvar gets ->send 21 $w->recv; # enters "main loop" till $condvar gets ->send
22
23=head1 INTRODUCTION/TUTORIAL
24
25This manpage is mainly a reference manual. If you are interested
26in a tutorial or some gentle introduction, have a look at the
27L<AnyEvent::Intro> manpage.
22 28
23=head1 WHY YOU SHOULD USE THIS MODULE (OR NOT) 29=head1 WHY YOU SHOULD USE THIS MODULE (OR NOT)
24 30
25Glib, POE, IO::Async, Event... CPAN offers event models by the dozen 31Glib, POE, IO::Async, Event... CPAN offers event models by the dozen
26nowadays. So what is different about AnyEvent? 32nowadays. So what is different about AnyEvent?
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243 249
244This returns the "current wallclock time" as a fractional number of 250This returns the "current wallclock time" as a fractional number of
245seconds since the Epoch (the same thing as C<time> or C<Time::HiRes::time> 251seconds since the Epoch (the same thing as C<time> or C<Time::HiRes::time>
246return, and the result is guaranteed to be compatible with those). 252return, and the result is guaranteed to be compatible with those).
247 253
248It progresses independently of any event loop processing. 254It progresses independently of any event loop processing, i.e. each call
249 255will check the system clock, which usually gets updated frequently.
250In almost all cases (in all cases if you don't care), this is the function
251to call when you want to know the current time.
252 256
253=item AnyEvent->now 257=item AnyEvent->now
254 258
255This also returns the "current wallclock time", but unlike C<time>, above, 259This also returns the "current wallclock time", but unlike C<time>, above,
256this value might change only once per event loop iteration, depending on 260this value might change only once per event loop iteration, depending on
257the event loop (most return the same time as C<time>, above). This is the 261the event loop (most return the same time as C<time>, above). This is the
258time that AnyEvent timers get scheduled against. 262time that AnyEvent's timers get scheduled against.
263
264I<In almost all cases (in all cases if you don't care), this is the
265function to call when you want to know the current time.>
266
267This function is also often faster then C<< AnyEvent->time >>, and
268thus the preferred method if you want some timestamp (for example,
269L<AnyEvent::Handle> uses this to update it's activity timeouts).
270
271The rest of this section is only of relevance if you try to be very exact
272with your timing, you can skip it without bad conscience.
259 273
260For a practical example of when these times differ, consider L<Event::Lib> 274For a practical example of when these times differ, consider L<Event::Lib>
261and L<EV> and the following set-up: 275and L<EV> and the following set-up:
262 276
263The event loop is running and has just invoked one of your callback at 277The event loop is running and has just invoked one of your callback at
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268 282
269With L<Event::Lib>, C<< AnyEvent->time >> and C<< AnyEvent->now >> will 283With L<Event::Lib>, C<< AnyEvent->time >> and C<< AnyEvent->now >> will
270both return C<501>, because that is the current time, and the timer will 284both return C<501>, because that is the current time, and the timer will
271be scheduled to fire at time=504 (C<501> + C<3>). 285be scheduled to fire at time=504 (C<501> + C<3>).
272 286
273With L<EV>m C<< AnyEvent->time >> returns C<501> (as that is the current 287With L<EV>, C<< AnyEvent->time >> returns C<501> (as that is the current
274time), but C<< AnyEvent->now >> returns C<500>, as that is the time the 288time), but C<< AnyEvent->now >> returns C<500>, as that is the time the
275last event processing phase started. With L<EV>, your timer gets scheduled 289last event processing phase started. With L<EV>, your timer gets scheduled
276to run at time=503 (C<500> + C<3>). 290to run at time=503 (C<500> + C<3>).
277 291
278In one sense, L<Event::Lib> is more exact, as it uses the current time 292In one sense, L<Event::Lib> is more exact, as it uses the current time
279regardless of any delays introduced by event processing. However, most 293regardless of any delays introduced by event processing. However, most
280callbacks do not expect large delays in processing, so this causes a 294callbacks do not expect large delays in processing, so this causes a
281higher drift (and a lot more syscalls to get the current time). 295higher drift (and a lot more system calls to get the current time).
282 296
283In another sense, L<EV> is more exact, as your timer will be scheduled at 297In another sense, L<EV> is more exact, as your timer will be scheduled at
284the same time, regardless of how long event processing actually took. 298the same time, regardless of how long event processing actually took.
285 299
286In either case, if you care (and in most cases, you don't), then you 300In either case, if you care (and in most cases, you don't), then you
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583 597
584This is a mutator function that returns the callback set and optionally 598This is a mutator function that returns the callback set and optionally
585replaces it before doing so. 599replaces it before doing so.
586 600
587The callback will be called when the condition becomes "true", i.e. when 601The callback will be called when the condition becomes "true", i.e. when
588C<send> or C<croak> are called. Calling C<recv> inside the callback 602C<send> or C<croak> are called, with the only argument being the condition
589or at any later time is guaranteed not to block. 603variable itself. Calling C<recv> inside the callback or at any later time
604is guaranteed not to block.
590 605
591=back 606=back
592 607
593=head1 GLOBAL VARIABLES AND FUNCTIONS 608=head1 GLOBAL VARIABLES AND FUNCTIONS
594 609
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792no warnings; 807no warnings;
793use strict; 808use strict;
794 809
795use Carp; 810use Carp;
796 811
797our $VERSION = '4.05'; 812our $VERSION = 4.11;
798our $MODEL; 813our $MODEL;
799 814
800our $AUTOLOAD; 815our $AUTOLOAD;
801our @ISA; 816our @ISA;
802 817

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