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Comparing EV-Loop-Async/Async.pm (file contents):
Revision 1.2 by root, Tue Jul 14 13:24:34 2009 UTC vs.
Revision 1.3 by root, Tue Jul 14 15:09:44 2009 UTC

… …
8 8
9 my $loop = EV::Loop::Async::default; 9 my $loop = EV::Loop::Async::default;
10 my $timer; 10 my $timer;
11 my $flag; 11 my $flag;
12 12
13 # create a watcher, but make sure the loop is locked
13 { 14 {
14 $loop->scope_lock; # lock the loop structures 15 $loop->scope_lock; # lock the loop structures
15 $timer = $loop->timer (5, 1, sub { $flag = 1 }); 16 $timer = $loop->timer (5, 1, sub { $flag = 1 });
16 $loop->nudge; # tell loop to take note of the timer 17 $loop->notify; # tell loop to take note of the timer
17 } 18 }
18 19
19 1 while $flag; # $flag will be set asynchronously 20 1 while $flag; # $flag will be set asynchronously
20 21
22 # implement a critical section, uninterrupted by any callbacks
21 { 23 {
22 $loop->interrupt->scope_block; 24 $loop->interrupt->scope_block;
23 # critical section, no watcher callback interruptions 25 # critical section, no watcher callback interruptions
24 } 26 }
25 27
26 # stop timer again 28 # stop the timer watcher again - locking is required once more
27
28 { 29 {
29 $loop->scope_lock; # lock the loop structures 30 $loop->scope_lock; # lock the loop structures
30 $timer->stop; 31 $timer->stop;
31 # no need to nudge 32 # no need to notify
32 } 33 }
33 34
34=head1 DESCRIPTION 35=head1 DESCRIPTION
35 36
36This module implements a rather specialised event loop - it takes a normal 37This module implements a rather specialised event loop - it takes a normal
… …
45See the documentation for L<Async::Interrupt> for details on when and how 46See the documentation for L<Async::Interrupt> for details on when and how
46your perl program can be interrupted (and how to avoid it), and how to 47your perl program can be interrupted (and how to avoid it), and how to
47integrate background event loops into foreground ones. 48integrate background event loops into foreground ones.
48 49
49=head1 FAQ 50=head1 FAQ
51
52=over 4
53
54=item Why on earth...???
55
56Sometimes you need lower latency for specific events, but it's too heavy
57to continuously poll for events. And perl already does this for you
58anyways, so this module only uses this existing mechanism.
59
60=item When do I have to lock?
61
62When in doubt, lock. Do not start or stop a watcher, do not create a
63watcher (unless with the C<_ns> methods) and do not DESTROY an active
64watcher without locking either.
65
66Any other event loop modifications need to be done while locked as
67well. So when in doubt, lock (best using C<scope_lock>).
68
69=item Why explicit locking?
70
71Because I was too lazy to wrap everything and there are probably only a
72few people on this world using this module.
73
74=back
50 75
51=head1 FUNCTIONS, METHODS AND VARIABLES OF THIS MODULE 76=head1 FUNCTIONS, METHODS AND VARIABLES OF THIS MODULE
52 77
53=over 4 78=over 4
54 79
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139 $self->_attach ($asy, $asy->signal_func); 164 $self->_attach ($asy, $asy->signal_func);
140 165
141 $self 166 $self
142} 167}
143 168
144=item $loop->nudge 169=item $loop->notify
145 170
146Wake up the asynchronous loop. This is useful after registering a new 171Wake up the asynchronous loop. This is useful after registering a new
147watcher, to ensure that the background event loop integrates the new 172watcher, to ensure that the background event loop integrates the new
148watcher(s) (which only happens when it iterates, which you can force by 173watcher(s) (which only happens when it iterates, which you can force by
149calling this method). 174calling this method).
150 175
151Without calling this method, the event loop I<eventually> takes notice 176Without calling this method, the event loop I<eventually> takes notice
152of new watchers, bit when this happens is not wlel-defined (can be 177of new watchers, bit when this happens is not well-defined (can be
153instantaneous, or take a few hours). 178instantaneous, or take a few hours).
154 179
155No locking is required. 180No locking is required.
156 181
157Example: lock the loop, create a timer, nudge the loop so it takes notice 182Example: lock the loop, create a timer, nudge the loop so it takes notice
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161 my $flag; 186 my $flag;
162 187
163 { 188 {
164 $loop->scope_lock; 189 $loop->scope_lock;
165 $timer = $loop->timer (1, 0, sub { $flag = 1 }); 190 $timer = $loop->timer (1, 0, sub { $flag = 1 });
166 $loop->nudge; 191 $loop->notify;
167 } 192 }
168 193
169 1 until $flag; 194 1 until $flag;
170 195
171=item $loop->lock 196=item $loop->lock

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