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Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.296 by root, Tue Nov 17 01:19:49 2009 UTC vs.
Revision 1.301 by root, Tue Dec 1 18:04:21 2009 UTC

… …
402correctly. 402correctly.
403 403
404Example: exit on SIGINT 404Example: exit on SIGINT
405 405
406 my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 }); 406 my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });
407
408=head3 Restart Behaviour
409
410While restart behaviour is up to the event loop implementation, most will
411not restart syscalls (that includes L<Async::Interrupt> and AnyEvent's
412pure perl implementation).
413
414=head3 Safe/Unsafe Signals
415
416Perl signals can be either "safe" (synchronous to opcode handling) or
417"unsafe" (asynchronous) - the former might get delayed indefinitely, the
418latter might corrupt your memory.
419
420AnyEvent signal handlers are, in addition, synchronous to the event loop,
421i.e. they will not interrupt your running perl program but will only be
422called as part of the normal event handling (just like timer, I/O etc.
423callbacks, too).
407 424
408=head3 Signal Races, Delays and Workarounds 425=head3 Signal Races, Delays and Workarounds
409 426
410Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching 427Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching
411callbacks to signals in a generic way, which is a pity, as you cannot 428callbacks to signals in a generic way, which is a pity, as you cannot
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1123 1140
1124BEGIN { AnyEvent::common_sense } 1141BEGIN { AnyEvent::common_sense }
1125 1142
1126use Carp (); 1143use Carp ();
1127 1144
1128our $VERSION = '5.202'; 1145our $VERSION = '5.21';
1129our $MODEL; 1146our $MODEL;
1130 1147
1131our $AUTOLOAD; 1148our $AUTOLOAD;
1132our @ISA; 1149our @ISA;
1133 1150
1134our @REGISTRY; 1151our @REGISTRY;
1135
1136our $WIN32;
1137 1152
1138our $VERBOSE; 1153our $VERBOSE;
1139 1154
1140BEGIN { 1155BEGIN {
1141 eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }"; 1156 eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }";
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2433it's built-in modules) are required to use it. 2448it's built-in modules) are required to use it.
2434 2449
2435That does not mean that AnyEvent won't take advantage of some additional 2450That does not mean that AnyEvent won't take advantage of some additional
2436modules if they are installed. 2451modules if they are installed.
2437 2452
2438This section epxlains which additional modules will be used, and how they 2453This section explains which additional modules will be used, and how they
2439affect AnyEvent's operetion. 2454affect AnyEvent's operation.
2440 2455
2441=over 4 2456=over 4
2442 2457
2443=item L<Async::Interrupt> 2458=item L<Async::Interrupt>
2444 2459
… …
2449catch the signals) with some delay (default is 10 seconds, look for 2464catch the signals) with some delay (default is 10 seconds, look for
2450C<$AnyEvent::MAX_SIGNAL_LATENCY>). 2465C<$AnyEvent::MAX_SIGNAL_LATENCY>).
2451 2466
2452If this module is available, then it will be used to implement signal 2467If this module is available, then it will be used to implement signal
2453catching, which means that signals will not be delayed, and the event loop 2468catching, which means that signals will not be delayed, and the event loop
2454will not be interrupted regularly, which is more efficient (And good for 2469will not be interrupted regularly, which is more efficient (and good for
2455battery life on laptops). 2470battery life on laptops).
2456 2471
2457This affects not just the pure-perl event loop, but also other event loops 2472This affects not just the pure-perl event loop, but also other event loops
2458that have no signal handling on their own (e.g. Glib, Tk, Qt). 2473that have no signal handling on their own (e.g. Glib, Tk, Qt).
2459 2474
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2509 2524
2510Most event libraries are not fork-safe. The ones who are usually are 2525Most event libraries are not fork-safe. The ones who are usually are
2511because they rely on inefficient but fork-safe C<select> or C<poll> 2526because they rely on inefficient but fork-safe C<select> or C<poll>
2512calls. Only L<EV> is fully fork-aware. 2527calls. Only L<EV> is fully fork-aware.
2513 2528
2529This means that, in general, you cannot fork and do event processing
2530in the child if a watcher was created before the fork (which in turn
2531initialises the event library).
2532
2514If you have to fork, you must either do so I<before> creating your first 2533If you have to fork, you must either do so I<before> creating your first
2515watcher OR you must not use AnyEvent at all in the child OR you must do 2534watcher OR you must not use AnyEvent at all in the child OR you must do
2516something completely out of the scope of AnyEvent. 2535something completely out of the scope of AnyEvent.
2536
2537The problem of doing event processing in the parent I<and> the child
2538is much more complicated: even for backends that I<are> fork-aware or
2539fork-safe, their behaviour is not usually what you want: fork clones all
2540watchers, that means all timers, I/O watchers etc. are active in both
2541parent and child, which is almost never what you want.
2517 2542
2518 2543
2519=head1 SECURITY CONSIDERATIONS 2544=head1 SECURITY CONSIDERATIONS
2520 2545
2521AnyEvent can be forced to load any event model via 2546AnyEvent can be forced to load any event model via

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