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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 1.305 by root, Sun Dec 13 05:13:15 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 $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });
407
408=head3 Restart Behaviour
409
410While restart behaviour is up to the event loop implementation, most will
411not restart syscalls (that includes L<Async::Interrupt> and AnyEvent's
412pure perl implementation).
413
414=head3 Safe/Unsafe Signals
415
416Perl signals can be either "safe" (synchronous to opcode handling) or
417"unsafe" (asynchronous) - the former might get delayed indefinitely, the
418latter might corrupt your memory.
419
420AnyEvent signal handlers are, in addition, synchronous to the event loop,
421i.e. they will not interrupt your running perl program but will only be
422called as part of the normal event handling (just like timer, I/O etc.
423callbacks, too).
407 424
408=head3 Signal Races, Delays and Workarounds 425=head3 Signal Races, Delays and Workarounds
409 426
410Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching 427Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching
411callbacks to signals in a generic way, which is a pity, as you cannot 428callbacks to signals in a generic way, which is a pity, as you cannot
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949You should check C<$AnyEvent::MODEL> before adding to this array, though: 966You should check C<$AnyEvent::MODEL> before adding to this array, though:
950if it is defined then the event loop has already been detected, and the 967if it is defined then the event loop has already been detected, and the
951array will be ignored. 968array will be ignored.
952 969
953Best use C<AnyEvent::post_detect { BLOCK }> when your application allows 970Best use C<AnyEvent::post_detect { BLOCK }> when your application allows
954it,as it takes care of these details. 971it, as it takes care of these details.
955 972
956This variable is mainly useful for modules that can do something useful 973This variable is mainly useful for modules that can do something useful
957when AnyEvent is used and thus want to know when it is initialised, but do 974when AnyEvent is used and thus want to know when it is initialised, but do
958not need to even load it by default. This array provides the means to hook 975not need to even load it by default. This array provides the means to hook
959into AnyEvent passively, without loading it. 976into AnyEvent passively, without loading it.
977
978Example: To load Coro::AnyEvent whenever Coro and AnyEvent are used
979together, you could put this into Coro (this is the actual code used by
980Coro to accomplish this):
981
982 if (defined $AnyEvent::MODEL) {
983 # AnyEvent already initialised, so load Coro::AnyEvent
984 require Coro::AnyEvent;
985 } else {
986 # AnyEvent not yet initialised, so make sure to load Coro::AnyEvent
987 # as soon as it is
988 push @AnyEvent::post_detect, sub { require Coro::AnyEvent };
989 }
960 990
961=back 991=back
962 992
963=head1 WHAT TO DO IN A MODULE 993=head1 WHAT TO DO IN A MODULE
964 994
… …
1114package AnyEvent; 1144package AnyEvent;
1115 1145
1116# basically a tuned-down version of common::sense 1146# basically a tuned-down version of common::sense
1117sub common_sense { 1147sub common_sense {
1118 # from common:.sense 1.0 1148 # from common:.sense 1.0
1119 ${^WARNING_BITS} = "\xfc\x3f\xf3\x00\x0f\xf3\xcf\xc0\xf3\xfc\x33\x03"; 1149 ${^WARNING_BITS} = "\xfc\x3f\x33\x00\x0f\xf3\xcf\xc0\xf3\xfc\x33\x00";
1120 # use strict vars subs 1150 # use strict vars subs
1121 $^H |= 0x00000600; 1151 $^H |= 0x00000600;
1122} 1152}
1123 1153
1124BEGIN { AnyEvent::common_sense } 1154BEGIN { AnyEvent::common_sense }
1125 1155
1126use Carp (); 1156use Carp ();
1127 1157
1128our $VERSION = '5.202'; 1158our $VERSION = '5.22';
1129our $MODEL; 1159our $MODEL;
1130 1160
1131our $AUTOLOAD; 1161our $AUTOLOAD;
1132our @ISA; 1162our @ISA;
1133 1163
1134our @REGISTRY; 1164our @REGISTRY;
1135
1136our $WIN32;
1137 1165
1138our $VERBOSE; 1166our $VERBOSE;
1139 1167
1140BEGIN { 1168BEGIN {
1141 eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }"; 1169 eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }";
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2433it's built-in modules) are required to use it. 2461it's built-in modules) are required to use it.
2434 2462
2435That does not mean that AnyEvent won't take advantage of some additional 2463That does not mean that AnyEvent won't take advantage of some additional
2436modules if they are installed. 2464modules if they are installed.
2437 2465
2438This section epxlains which additional modules will be used, and how they 2466This section explains which additional modules will be used, and how they
2439affect AnyEvent's operetion. 2467affect AnyEvent's operation.
2440 2468
2441=over 4 2469=over 4
2442 2470
2443=item L<Async::Interrupt> 2471=item L<Async::Interrupt>
2444 2472
… …
2449catch the signals) with some delay (default is 10 seconds, look for 2477catch the signals) with some delay (default is 10 seconds, look for
2450C<$AnyEvent::MAX_SIGNAL_LATENCY>). 2478C<$AnyEvent::MAX_SIGNAL_LATENCY>).
2451 2479
2452If this module is available, then it will be used to implement signal 2480If 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 2481catching, which means that signals will not be delayed, and the event loop
2454will not be interrupted regularly, which is more efficient (And good for 2482will not be interrupted regularly, which is more efficient (and good for
2455battery life on laptops). 2483battery life on laptops).
2456 2484
2457This affects not just the pure-perl event loop, but also other event loops 2485This 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). 2486that have no signal handling on their own (e.g. Glib, Tk, Qt).
2459 2487
… …
2509 2537
2510Most event libraries are not fork-safe. The ones who are usually are 2538Most 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> 2539because they rely on inefficient but fork-safe C<select> or C<poll>
2512calls. Only L<EV> is fully fork-aware. 2540calls. Only L<EV> is fully fork-aware.
2513 2541
2542This means that, in general, you cannot fork and do event processing
2543in the child if a watcher was created before the fork (which in turn
2544initialises the event library).
2545
2514If you have to fork, you must either do so I<before> creating your first 2546If 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 2547watcher OR you must not use AnyEvent at all in the child OR you must do
2516something completely out of the scope of AnyEvent. 2548something completely out of the scope of AnyEvent.
2549
2550The problem of doing event processing in the parent I<and> the child
2551is much more complicated: even for backends that I<are> fork-aware or
2552fork-safe, their behaviour is not usually what you want: fork clones all
2553watchers, that means all timers, I/O watchers etc. are active in both
2554parent and child, which is almost never what you want.
2517 2555
2518 2556
2519=head1 SECURITY CONSIDERATIONS 2557=head1 SECURITY CONSIDERATIONS
2520 2558
2521AnyEvent can be forced to load any event model via 2559AnyEvent can be forced to load any event model via

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