… | |
… | |
152 | =head2 I/O WATCHERS |
152 | =head2 I/O WATCHERS |
153 | |
153 | |
154 | You can create an I/O watcher by calling the C<< AnyEvent->io >> method |
154 | You can create an I/O watcher by calling the C<< AnyEvent->io >> method |
155 | with the following mandatory key-value pairs as arguments: |
155 | with the following mandatory key-value pairs as arguments: |
156 | |
156 | |
157 | C<fh> the Perl I<file handle> (I<not> file descriptor) to watch |
157 | C<fh> the Perl I<file handle> (I<not> file descriptor) to watch for events |
158 | for events. C<poll> must be a string that is either C<r> or C<w>, |
158 | (AnyEvent might or might not keep a reference to this file handle). C<poll> |
159 | which creates a watcher waiting for "r"eadable or "w"ritable events, |
159 | must be a string that is either C<r> or C<w>, which creates a watcher |
160 | respectively. C<cb> is the callback to invoke each time the file handle |
160 | waiting for "r"eadable or "w"ritable events, respectively. C<cb> is the |
161 | becomes ready. |
161 | callback to invoke each time the file handle becomes ready. |
162 | |
162 | |
163 | Although the callback might get passed parameters, their value and |
163 | Although the callback might get passed parameters, their value and |
164 | presence is undefined and you cannot rely on them. Portable AnyEvent |
164 | presence is undefined and you cannot rely on them. Portable AnyEvent |
165 | callbacks cannot use arguments passed to I/O watcher callbacks. |
165 | callbacks cannot use arguments passed to I/O watcher callbacks. |
166 | |
166 | |
… | |
… | |
170 | |
170 | |
171 | Some event loops issue spurious readyness notifications, so you should |
171 | Some event loops issue spurious readyness notifications, so you should |
172 | always use non-blocking calls when reading/writing from/to your file |
172 | always use non-blocking calls when reading/writing from/to your file |
173 | handles. |
173 | handles. |
174 | |
174 | |
175 | Example: |
|
|
176 | |
|
|
177 | # wait for readability of STDIN, then read a line and disable the watcher |
175 | Example: wait for readability of STDIN, then read a line and disable the |
|
|
176 | watcher. |
|
|
177 | |
178 | my $w; $w = AnyEvent->io (fh => \*STDIN, poll => 'r', cb => sub { |
178 | my $w; $w = AnyEvent->io (fh => \*STDIN, poll => 'r', cb => sub { |
179 | chomp (my $input = <STDIN>); |
179 | chomp (my $input = <STDIN>); |
180 | warn "read: $input\n"; |
180 | warn "read: $input\n"; |
181 | undef $w; |
181 | undef $w; |
182 | }); |
182 | }); |
… | |
… | |
192 | |
192 | |
193 | Although the callback might get passed parameters, their value and |
193 | Although the callback might get passed parameters, their value and |
194 | presence is undefined and you cannot rely on them. Portable AnyEvent |
194 | presence is undefined and you cannot rely on them. Portable AnyEvent |
195 | callbacks cannot use arguments passed to time watcher callbacks. |
195 | callbacks cannot use arguments passed to time watcher callbacks. |
196 | |
196 | |
197 | The timer callback will be invoked at most once: if you want a repeating |
197 | The callback will normally be invoked once only. If you specify another |
198 | timer you have to create a new watcher (this is a limitation by both Tk |
198 | parameter, C<interval>, as a strictly positive number (> 0), then the |
199 | and Glib). |
199 | callback will be invoked regularly at that interval (in fractional |
|
|
200 | seconds) after the first invocation. If C<interval> is specified with a |
|
|
201 | false value, then it is treated as if it were missing. |
200 | |
202 | |
201 | Example: |
203 | The callback will be rescheduled before invoking the callback, but no |
|
|
204 | attempt is done to avoid timer drift in most backends, so the interval is |
|
|
205 | only approximate. |
202 | |
206 | |
203 | # fire an event after 7.7 seconds |
207 | Example: fire an event after 7.7 seconds. |
|
|
208 | |
204 | my $w = AnyEvent->timer (after => 7.7, cb => sub { |
209 | my $w = AnyEvent->timer (after => 7.7, cb => sub { |
205 | warn "timeout\n"; |
210 | warn "timeout\n"; |
206 | }); |
211 | }); |
207 | |
212 | |
208 | # to cancel the timer: |
213 | # to cancel the timer: |
209 | undef $w; |
214 | undef $w; |
210 | |
215 | |
211 | Example 2: |
|
|
212 | |
|
|
213 | # fire an event after 0.5 seconds, then roughly every second |
216 | Example 2: fire an event after 0.5 seconds, then roughly every second. |
214 | my $w; |
|
|
215 | |
217 | |
216 | my $cb = sub { |
|
|
217 | # cancel the old timer while creating a new one |
|
|
218 | $w = AnyEvent->timer (after => 1, cb => $cb); |
218 | my $w = AnyEvent->timer (after => 0.5, interval => 1, cb => sub { |
|
|
219 | warn "timeout\n"; |
219 | }; |
220 | }; |
220 | |
|
|
221 | # start the "loop" by creating the first watcher |
|
|
222 | $w = AnyEvent->timer (after => 0.5, cb => $cb); |
|
|
223 | |
221 | |
224 | =head3 TIMING ISSUES |
222 | =head3 TIMING ISSUES |
225 | |
223 | |
226 | There are two ways to handle timers: based on real time (relative, "fire |
224 | There are two ways to handle timers: based on real time (relative, "fire |
227 | in 10 seconds") and based on wallclock time (absolute, "fire at 12 |
225 | in 10 seconds") and based on wallclock time (absolute, "fire at 12 |
… | |
… | |
738 | =item L<AnyEvent::Util> |
736 | =item L<AnyEvent::Util> |
739 | |
737 | |
740 | Contains various utility functions that replace often-used but blocking |
738 | Contains various utility functions that replace often-used but blocking |
741 | functions such as C<inet_aton> by event-/callback-based versions. |
739 | functions such as C<inet_aton> by event-/callback-based versions. |
742 | |
740 | |
743 | =item L<AnyEvent::Handle> |
|
|
744 | |
|
|
745 | Provide read and write buffers and manages watchers for reads and writes. |
|
|
746 | |
|
|
747 | =item L<AnyEvent::Socket> |
741 | =item L<AnyEvent::Socket> |
748 | |
742 | |
749 | Provides various utility functions for (internet protocol) sockets, |
743 | Provides various utility functions for (internet protocol) sockets, |
750 | addresses and name resolution. Also functions to create non-blocking tcp |
744 | addresses and name resolution. Also functions to create non-blocking tcp |
751 | connections or tcp servers, with IPv6 and SRV record support and more. |
745 | connections or tcp servers, with IPv6 and SRV record support and more. |
752 | |
746 | |
|
|
747 | =item L<AnyEvent::Handle> |
|
|
748 | |
|
|
749 | Provide read and write buffers, manages watchers for reads and writes, |
|
|
750 | supports raw and formatted I/O, I/O queued and fully transparent and |
|
|
751 | non-blocking SSL/TLS. |
|
|
752 | |
753 | =item L<AnyEvent::DNS> |
753 | =item L<AnyEvent::DNS> |
754 | |
754 | |
755 | Provides rich asynchronous DNS resolver capabilities. |
755 | Provides rich asynchronous DNS resolver capabilities. |
756 | |
756 | |
757 | =item L<AnyEvent::HTTP> |
757 | =item L<AnyEvent::HTTP> |
… | |
… | |
767 | |
767 | |
768 | The fastest ping in the west. |
768 | The fastest ping in the west. |
769 | |
769 | |
770 | =item L<AnyEvent::DBI> |
770 | =item L<AnyEvent::DBI> |
771 | |
771 | |
772 | Executes DBI requests asynchronously in a proxy process. |
772 | Executes L<DBI> requests asynchronously in a proxy process. |
|
|
773 | |
|
|
774 | =item L<AnyEvent::AIO> |
|
|
775 | |
|
|
776 | Truly asynchronous I/O, should be in the toolbox of every event |
|
|
777 | programmer. AnyEvent::AIO transparently fuses L<IO::AIO> and AnyEvent |
|
|
778 | together. |
|
|
779 | |
|
|
780 | =item L<AnyEvent::BDB> |
|
|
781 | |
|
|
782 | Truly asynchronous Berkeley DB access. AnyEvent::BDB transparently fuses |
|
|
783 | L<BDB> and AnyEvent together. |
|
|
784 | |
|
|
785 | =item L<AnyEvent::GPSD> |
|
|
786 | |
|
|
787 | A non-blocking interface to gpsd, a daemon delivering GPS information. |
|
|
788 | |
|
|
789 | =item L<AnyEvent::IGS> |
|
|
790 | |
|
|
791 | A non-blocking interface to the Internet Go Server protocol (used by |
|
|
792 | L<App::IGS>). |
773 | |
793 | |
774 | =item L<Net::IRC3> |
794 | =item L<Net::IRC3> |
775 | |
795 | |
776 | AnyEvent based IRC client module family. |
796 | AnyEvent based IRC client module family. |
777 | |
797 | |
… | |
… | |
790 | |
810 | |
791 | =item L<Coro> |
811 | =item L<Coro> |
792 | |
812 | |
793 | Has special support for AnyEvent via L<Coro::AnyEvent>. |
813 | Has special support for AnyEvent via L<Coro::AnyEvent>. |
794 | |
814 | |
795 | =item L<AnyEvent::AIO>, L<IO::AIO> |
|
|
796 | |
|
|
797 | Truly asynchronous I/O, should be in the toolbox of every event |
|
|
798 | programmer. AnyEvent::AIO transparently fuses IO::AIO and AnyEvent |
|
|
799 | together. |
|
|
800 | |
|
|
801 | =item L<AnyEvent::BDB>, L<BDB> |
|
|
802 | |
|
|
803 | Truly asynchronous Berkeley DB access. AnyEvent::AIO transparently fuses |
|
|
804 | IO::AIO and AnyEvent together. |
|
|
805 | |
|
|
806 | =item L<IO::Lambda> |
815 | =item L<IO::Lambda> |
807 | |
816 | |
808 | The lambda approach to I/O - don't ask, look there. Can use AnyEvent. |
817 | The lambda approach to I/O - don't ask, look there. Can use AnyEvent. |
809 | |
818 | |
810 | =back |
819 | =back |
… | |
… | |
816 | no warnings; |
825 | no warnings; |
817 | use strict; |
826 | use strict; |
818 | |
827 | |
819 | use Carp; |
828 | use Carp; |
820 | |
829 | |
821 | our $VERSION = 4.160; |
830 | our $VERSION = 4.2; |
822 | our $MODEL; |
831 | our $MODEL; |
823 | |
832 | |
824 | our $AUTOLOAD; |
833 | our $AUTOLOAD; |
825 | our @ISA; |
834 | our @ISA; |
826 | |
835 | |