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Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.265 by root, Wed Jul 29 13:10:58 2009 UTC vs.
Revision 1.275 by root, Sun Aug 9 00:24:35 2009 UTC

181my variables are only visible after the statement in which they are 181my variables are only visible after the statement in which they are
182declared. 182declared.
183 183
184=head2 I/O WATCHERS 184=head2 I/O WATCHERS
185 185
186 $w = AnyEvent->io (
187 fh => <filehandle_or_fileno>,
188 poll => <"r" or "w">,
189 cb => <callback>,
190 );
191
186You can create an I/O watcher by calling the C<< AnyEvent->io >> method 192You can create an I/O watcher by calling the C<< AnyEvent->io >> method
187with the following mandatory key-value pairs as arguments: 193with the following mandatory key-value pairs as arguments:
188 194
189C<fh> is the Perl I<file handle> (or a naked file descriptor) to watch 195C<fh> is the Perl I<file handle> (or a naked file descriptor) to watch
190for events (AnyEvent might or might not keep a reference to this file 196for events (AnyEvent might or might not keep a reference to this file
219 undef $w; 225 undef $w;
220 }); 226 });
221 227
222=head2 TIME WATCHERS 228=head2 TIME WATCHERS
223 229
230 $w = AnyEvent->timer (after => <seconds>, cb => <callback>);
231
232 $w = AnyEvent->timer (
233 after => <fractional_seconds>,
234 interval => <fractional_seconds>,
235 cb => <callback>,
236 );
237
224You can create a time watcher by calling the C<< AnyEvent->timer >> 238You can create a time watcher by calling the C<< AnyEvent->timer >>
225method with the following mandatory arguments: 239method with the following mandatory arguments:
226 240
227C<after> specifies after how many seconds (fractional values are 241C<after> specifies after how many seconds (fractional values are
228supported) the callback should be invoked. C<cb> is the callback to invoke 242supported) the callback should be invoked. C<cb> is the callback to invoke
355 369
356=back 370=back
357 371
358=head2 SIGNAL WATCHERS 372=head2 SIGNAL WATCHERS
359 373
374 $w = AnyEvent->signal (signal => <uppercase_signal_name>, cb => <callback>);
375
360You can watch for signals using a signal watcher, C<signal> is the signal 376You can watch for signals using a signal watcher, C<signal> is the signal
361I<name> in uppercase and without any C<SIG> prefix, C<cb> is the Perl 377I<name> in uppercase and without any C<SIG> prefix, C<cb> is the Perl
362callback to be invoked whenever a signal occurs. 378callback to be invoked whenever a signal occurs.
363 379
364Although the callback might get passed parameters, their value and 380Although the callback might get passed parameters, their value and
383 my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 }); 399 my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });
384 400
385=head3 Signal Races, Delays and Workarounds 401=head3 Signal Races, Delays and Workarounds
386 402
387Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching 403Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching
388callbacks to signals in a generic way, which is a pity, as you cannot do 404callbacks to signals in a generic way, which is a pity, as you cannot
389race-free signal handling in perl. AnyEvent will try to do it's best, but 405do race-free signal handling in perl, requiring C libraries for
406this. AnyEvent will try to do it's best, which means in some cases,
390in some cases, signals will be delayed. The maximum time a signal might 407signals will be delayed. The maximum time a signal might be delayed is
391be delayed is specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 408specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 seconds). This
392seconds). This variable can be changed only before the first signal 409variable can be changed only before the first signal watcher is created,
393watcher is created, and should be left alone otherwise. Higher values 410and should be left alone otherwise. This variable determines how often
411AnyEvent polls for signals (in case a wake-up was missed). Higher values
394will cause fewer spurious wake-ups, which is better for power and CPU 412will cause fewer spurious wake-ups, which is better for power and CPU
413saving.
414
395saving. All these problems can be avoided by installing the optional 415All these problems can be avoided by installing the optional
396L<Async::Interrupt> module. This will not work with inherently broken 416L<Async::Interrupt> module, which works with most event loops. It will not
397event loops such as L<Event> or L<Event::Lib> (and not with L<POE> 417work with inherently broken event loops such as L<Event> or L<Event::Lib>
398currently, as POE does it's own workaround with one-second latency). With 418(and not with L<POE> currently, as POE does it's own workaround with
399those, you just have to suffer the delays. 419one-second latency). For those, you just have to suffer the delays.
400 420
401=head2 CHILD PROCESS WATCHERS 421=head2 CHILD PROCESS WATCHERS
422
423 $w = AnyEvent->child (pid => <process id>, cb => <callback>);
402 424
403You can also watch on a child process exit and catch its exit status. 425You can also watch on a child process exit and catch its exit status.
404 426
405The child process is specified by the C<pid> argument (one some backends, 427The child process is specified by the C<pid> argument (one some backends,
406using C<0> watches for any child process exit, on others this will 428using C<0> watches for any child process exit, on others this will
455 # do something else, then wait for process exit 477 # do something else, then wait for process exit
456 $done->recv; 478 $done->recv;
457 479
458=head2 IDLE WATCHERS 480=head2 IDLE WATCHERS
459 481
482 $w = AnyEvent->idle (cb => <callback>);
483
460Sometimes there is a need to do something, but it is not so important 484Sometimes there is a need to do something, but it is not so important
461to do it instantly, but only when there is nothing better to do. This 485to do it instantly, but only when there is nothing better to do. This
462"nothing better to do" is usually defined to be "no other events need 486"nothing better to do" is usually defined to be "no other events need
463attention by the event loop". 487attention by the event loop".
464 488
490 }); 514 });
491 }); 515 });
492 516
493=head2 CONDITION VARIABLES 517=head2 CONDITION VARIABLES
494 518
519 $cv = AnyEvent->condvar;
520
521 $cv->send (<list>);
522 my @res = $cv->recv;
523
495If you are familiar with some event loops you will know that all of them 524If you are familiar with some event loops you will know that all of them
496require you to run some blocking "loop", "run" or similar function that 525require you to run some blocking "loop", "run" or similar function that
497will actively watch for new events and call your callbacks. 526will actively watch for new events and call your callbacks.
498 527
499AnyEvent is slightly different: it expects somebody else to run the event 528AnyEvent is slightly different: it expects somebody else to run the event
761=item $cb = $cv->cb ($cb->($cv)) 790=item $cb = $cv->cb ($cb->($cv))
762 791
763This is a mutator function that returns the callback set and optionally 792This is a mutator function that returns the callback set and optionally
764replaces it before doing so. 793replaces it before doing so.
765 794
766The callback will be called when the condition becomes "true", i.e. when 795The callback will be called when the condition becomes (or already was)
767C<send> or C<croak> are called, with the only argument being the condition 796"true", i.e. when C<send> or C<croak> are called (or were called), with
768variable itself. Calling C<recv> inside the callback or at any later time 797the only argument being the condition variable itself. Calling C<recv>
769is guaranteed not to block. 798inside the callback or at any later time is guaranteed not to block.
770 799
771=back 800=back
772 801
773=head1 SUPPORTED EVENT LOOPS/BACKENDS 802=head1 SUPPORTED EVENT LOOPS/BACKENDS
774 803
1086 1115
1087BEGIN { AnyEvent::common_sense } 1116BEGIN { AnyEvent::common_sense }
1088 1117
1089use Carp (); 1118use Carp ();
1090 1119
1091our $VERSION = 4.881; 1120our $VERSION = 4.92;
1092our $MODEL; 1121our $MODEL;
1093 1122
1094our $AUTOLOAD; 1123our $AUTOLOAD;
1095our @ISA; 1124our @ISA;
1096 1125
1258 # we assume CLOEXEC is already set by perl in all important cases 1287 # we assume CLOEXEC is already set by perl in all important cases
1259 1288
1260 ($fh2, $rw) 1289 ($fh2, $rw)
1261} 1290}
1262 1291
1292#############################################################################
1293# "new" API, currently only emulation of it
1294#############################################################################
1295
1296package AE;
1297
1298our $VERSION = $AnyEvent::VERSION;
1299
1300sub io($$$) {
1301 AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2])
1302}
1303
1304sub timer($$$) {
1305 AnyEvent->timer (after => $_[0], interval => $_[1], cb => $_[2]);
1306}
1307
1308sub signal($$) {
1309 AnyEvent->signal (signal => $_[0], cb => $_[1]);
1310}
1311
1312sub child($$) {
1313 AnyEvent->child (pid => $_[0], cb => $_[1]);
1314}
1315
1316sub idle($) {
1317 AnyEvent->idle (cb => $_[0]);
1318}
1319
1320sub cv(;&) {
1321 AnyEvent->condvar (@_ ? (cb => $_[0]) : ())
1322}
1323
1324sub now() {
1325 AnyEvent->now
1326}
1327
1328sub now_update() {
1329 AnyEvent->now_update
1330}
1331
1332sub time() {
1333 AnyEvent->time
1334}
1335
1263package AnyEvent::Base; 1336package AnyEvent::Base;
1264 1337
1265# default implementations for many methods 1338# default implementations for many methods
1266 1339
1267sub _time { 1340sub _time {
1319 1392
1320# install a dummy wakeup watcher to reduce signal catching latency 1393# install a dummy wakeup watcher to reduce signal catching latency
1321sub _sig_add() { 1394sub _sig_add() {
1322 unless ($SIG_COUNT++) { 1395 unless ($SIG_COUNT++) {
1323 # try to align timer on a full-second boundary, if possible 1396 # try to align timer on a full-second boundary, if possible
1324 my $NOW = AnyEvent->now; 1397 my $NOW = AE::now;
1325 1398
1326 $SIG_TW = AnyEvent->timer ( 1399 $SIG_TW = AE::timer
1327 after => $MAX_SIGNAL_LATENCY - ($NOW - int $NOW), 1400 $MAX_SIGNAL_LATENCY - ($NOW - int $NOW),
1328 interval => $MAX_SIGNAL_LATENCY, 1401 $MAX_SIGNAL_LATENCY,
1329 cb => sub { }, # just for the PERL_ASYNC_CHECK 1402 sub { } # just for the PERL_ASYNC_CHECK
1330 ); 1403 ;
1331 } 1404 }
1332} 1405}
1333 1406
1334sub _sig_del { 1407sub _sig_del {
1335 undef $SIG_TW 1408 undef $SIG_TW
1372 # probe for availability of Async::Interrupt 1445 # probe for availability of Async::Interrupt
1373 if (_have_async_interrupt) { 1446 if (_have_async_interrupt) {
1374 warn "AnyEvent: using Async::Interrupt for race-free signal handling.\n" if $VERBOSE >= 8; 1447 warn "AnyEvent: using Async::Interrupt for race-free signal handling.\n" if $VERBOSE >= 8;
1375 1448
1376 $SIGPIPE_R = new Async::Interrupt::EventPipe; 1449 $SIGPIPE_R = new Async::Interrupt::EventPipe;
1377 $SIG_IO = AnyEvent->io (fh => $SIGPIPE_R->fileno, poll => "r", cb => \&_signal_exec); 1450 $SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec;
1378 1451
1379 } else { 1452 } else {
1380 warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8; 1453 warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8;
1381 1454
1382 require Fcntl; 1455 require Fcntl;
1398 } 1471 }
1399 1472
1400 $SIGPIPE_R 1473 $SIGPIPE_R
1401 or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n"; 1474 or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";
1402 1475
1403 $SIG_IO = AnyEvent->io (fh => $SIGPIPE_R, poll => "r", cb => \&_signal_exec); 1476 $SIG_IO = AE::io $SIGPIPE_R, 0, \&_signal_exec;
1404 } 1477 }
1405 1478
1406 *signal = sub { 1479 *signal = sub {
1407 my (undef, %arg) = @_; 1480 my (undef, %arg) = @_;
1408 1481
1497 $WNOHANG ||= $^O =~ /^(?:openbsd|netbsd|linux|freebsd|cygwin|MSWin32)$/ 1570 $WNOHANG ||= $^O =~ /^(?:openbsd|netbsd|linux|freebsd|cygwin|MSWin32)$/
1498 ? 1 1571 ? 1
1499 : eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1; 1572 : eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1;
1500 1573
1501 unless ($CHLD_W) { 1574 unless ($CHLD_W) {
1502 $CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld); 1575 $CHLD_W = AE::signal CHLD => \&_sigchld;
1503 # child could be a zombie already, so make at least one round 1576 # child could be a zombie already, so make at least one round
1504 &_sigchld; 1577 &_sigchld;
1505 } 1578 }
1506 1579
1507 bless [$pid, $arg{cb}], "AnyEvent::Base::child" 1580 bless [$pid, $arg{cb}], "AnyEvent::Base::child"
1533 # never use more then 50% of the time for the idle watcher, 1606 # never use more then 50% of the time for the idle watcher,
1534 # within some limits 1607 # within some limits
1535 $w = 0.0001 if $w < 0.0001; 1608 $w = 0.0001 if $w < 0.0001;
1536 $w = 5 if $w > 5; 1609 $w = 5 if $w > 5;
1537 1610
1538 $w = AnyEvent->timer (after => $w, cb => $rcb); 1611 $w = AE::timer $w, 0, $rcb;
1539 } else { 1612 } else {
1540 # clean up... 1613 # clean up...
1541 undef $w; 1614 undef $w;
1542 undef $rcb; 1615 undef $rcb;
1543 } 1616 }
1544 }; 1617 };
1545 1618
1546 $w = AnyEvent->timer (after => 0.05, cb => $rcb); 1619 $w = AE::timer 0.05, 0, $rcb;
1547 1620
1548 bless \\$cb, "AnyEvent::Base::idle" 1621 bless \\$cb, "AnyEvent::Base::idle"
1549} 1622}
1550 1623
1551sub AnyEvent::Base::idle::DESTROY { 1624sub AnyEvent::Base::idle::DESTROY {
1605 Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak}; 1678 Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak};
1606 wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0] 1679 wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0]
1607} 1680}
1608 1681
1609sub cb { 1682sub cb {
1610 $_[0]{_ae_cb} = $_[1] if @_ > 1; 1683 my $cv = shift;
1684
1685 @_
1686 and $cv->{_ae_cb} = shift
1687 and $cv->{_ae_sent}
1688 and (delete $cv->{_ae_cb})->($cv);
1689
1611 $_[0]{_ae_cb} 1690 $cv->{_ae_cb}
1612} 1691}
1613 1692
1614sub begin { 1693sub begin {
1615 ++$_[0]{_ae_counter}; 1694 ++$_[0]{_ae_counter};
1616 $_[0]{_ae_end_cb} = $_[1] if @_ > 1; 1695 $_[0]{_ae_end_cb} = $_[1] if @_ > 1;

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