1 | =head1 NAME |
1 | =head1 NAME |
2 | |
2 | |
3 | AnyEvent - provide framework for multiple event loops |
3 | AnyEvent - provide framework for multiple event loops |
4 | |
4 | |
5 | Event, Coro, Glib, Tk, Perl - various supported event loops |
5 | EV, Event, Coro::EV, Coro::Event, Glib, Tk, Perl, Event::Lib, Qt, POE - various supported event loops |
6 | |
6 | |
7 | =head1 SYNOPSIS |
7 | =head1 SYNOPSIS |
8 | |
8 | |
9 | use AnyEvent; |
9 | use AnyEvent; |
10 | |
10 | |
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14 | |
14 | |
15 | my $w = AnyEvent->timer (after => $seconds, cb => sub { |
15 | my $w = AnyEvent->timer (after => $seconds, cb => sub { |
16 | ... |
16 | ... |
17 | }); |
17 | }); |
18 | |
18 | |
19 | my $w = AnyEvent->condvar; # stores wether a condition was flagged |
19 | my $w = AnyEvent->condvar; # stores whether a condition was flagged |
20 | $w->wait; # enters "main loop" till $condvar gets ->broadcast |
20 | $w->wait; # enters "main loop" till $condvar gets ->broadcast |
21 | $w->broadcast; # wake up current and all future wait's |
21 | $w->broadcast; # wake up current and all future wait's |
22 | |
22 | |
23 | =head1 WHY YOU SHOULD USE THIS MODULE (OR NOT) |
23 | =head1 WHY YOU SHOULD USE THIS MODULE (OR NOT) |
24 | |
24 | |
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29 | policy> and AnyEvent is I<small and efficient>. |
29 | policy> and AnyEvent is I<small and efficient>. |
30 | |
30 | |
31 | First and foremost, I<AnyEvent is not an event model> itself, it only |
31 | First and foremost, I<AnyEvent is not an event model> itself, it only |
32 | interfaces to whatever event model the main program happens to use in a |
32 | interfaces to whatever event model the main program happens to use in a |
33 | pragmatic way. For event models and certain classes of immortals alike, |
33 | pragmatic way. For event models and certain classes of immortals alike, |
34 | the statement "there can only be one" is a bitter reality, and AnyEvent |
34 | the statement "there can only be one" is a bitter reality: In general, |
35 | helps hiding the differences. |
35 | only one event loop can be active at the same time in a process. AnyEvent |
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36 | helps hiding the differences between those event loops. |
36 | |
37 | |
37 | The goal of AnyEvent is to offer module authors the ability to do event |
38 | The goal of AnyEvent is to offer module authors the ability to do event |
38 | programming (waiting for I/O or timer events) without subscribing to a |
39 | programming (waiting for I/O or timer events) without subscribing to a |
39 | religion, a way of living, and most importantly: without forcing your |
40 | religion, a way of living, and most importantly: without forcing your |
40 | module users into the same thing by forcing them to use the same event |
41 | module users into the same thing by forcing them to use the same event |
41 | model you use. |
42 | model you use. |
42 | |
43 | |
43 | For modules like POE or IO::Async (which is actually doing all I/O |
44 | For modules like POE or IO::Async (which is a total misnomer as it is |
44 | I<synchronously>...), using them in your module is like joining a |
45 | actually doing all I/O I<synchronously>...), using them in your module is |
45 | cult: After you joined, you are dependent on them and you cannot use |
46 | like joining a cult: After you joined, you are dependent on them and you |
46 | anything else, as it is simply incompatible to everything that isn't |
47 | cannot use anything else, as it is simply incompatible to everything that |
47 | itself. |
48 | isn't itself. What's worse, all the potential users of your module are |
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49 | I<also> forced to use the same event loop you use. |
48 | |
50 | |
49 | AnyEvent + POE works fine. AnyEvent + Glib works fine. AnyEvent + Tk |
51 | AnyEvent is different: AnyEvent + POE works fine. AnyEvent + Glib works |
50 | works fine etc. etc. but none of these work together with the rest: POE |
52 | fine. AnyEvent + Tk works fine etc. etc. but none of these work together |
51 | + IO::Async? no go. Tk + Event? no go. If your module uses one of |
53 | with the rest: POE + IO::Async? no go. Tk + Event? no go. Again: if |
52 | those, every user of your module has to use it, too. If your module |
54 | your module uses one of those, every user of your module has to use it, |
53 | uses AnyEvent, it works transparently with all event models it supports |
55 | too. But if your module uses AnyEvent, it works transparently with all |
54 | (including stuff like POE and IO::Async). |
56 | event models it supports (including stuff like POE and IO::Async, as long |
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57 | as those use one of the supported event loops. It is trivial to add new |
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58 | event loops to AnyEvent, too, so it is future-proof). |
55 | |
59 | |
56 | In addition of being free of having to use I<the one and only true event |
60 | In addition to being free of having to use I<the one and only true event |
57 | model>, AnyEvent also is free of bloat and policy: with POE or similar |
61 | model>, AnyEvent also is free of bloat and policy: with POE or similar |
58 | modules, you get an enourmous amount of code and strict rules you have |
62 | modules, you get an enourmous amount of code and strict rules you have to |
59 | to follow. AnyEvent, on the other hand, is lean and to the point by only |
63 | follow. AnyEvent, on the other hand, is lean and up to the point, by only |
60 | offering the functionality that is useful, in as thin as a wrapper as |
64 | offering the functionality that is necessary, in as thin as a wrapper as |
61 | technically possible. |
65 | technically possible. |
62 | |
66 | |
63 | Of course, if you want lots of policy (this is arguably somewhat useful |
67 | Of course, if you want lots of policy (this can arguably be somewhat |
64 | in many cases) and you want to force your users to the one and only event |
68 | useful) and you want to force your users to use the one and only event |
65 | model your module forces on them, you should I<not> use this module. |
69 | model, you should I<not> use this module. |
66 | |
70 | |
67 | |
71 | |
68 | =head1 DESCRIPTION |
72 | =head1 DESCRIPTION |
69 | |
73 | |
70 | L<AnyEvent> provides an identical interface to multiple event loops. This |
74 | L<AnyEvent> provides an identical interface to multiple event loops. This |
71 | allows module authors to utilise an event loop without forcing module |
75 | allows module authors to utilise an event loop without forcing module |
72 | users to use the same event loop (as only a single event loop can coexist |
76 | users to use the same event loop (as only a single event loop can coexist |
73 | peacefully at any one time). |
77 | peacefully at any one time). |
74 | |
78 | |
75 | The interface itself is vaguely similar but not identical to the Event |
79 | The interface itself is vaguely similar, but not identical to the L<Event> |
76 | module. |
80 | module. |
77 | |
81 | |
78 | On the first call of any method, the module tries to detect the currently |
82 | During the first call of any watcher-creation method, the module tries |
79 | loaded event loop by probing wether any of the following modules is |
83 | to detect the currently loaded event loop by probing whether one of the |
80 | loaded: L<Coro::Event>, L<Event>, L<Glib>, L<Tk>. The first one found is |
84 | following modules is already loaded: L<Coro::EV>, L<Coro::Event>, L<EV>, |
81 | used. If none is found, the module tries to load these modules in the |
85 | L<Event>, L<Glib>, L<Tk>, L<AnyEvent::Impl::Perl>, L<Event::Lib>, L<Qt>, |
82 | order given. The first one that could be successfully loaded will be |
86 | L<POE>. The first one found is used. If none are found, the module tries |
83 | used. If still none could be found, AnyEvent will fall back to a pure-perl |
87 | to load these modules (excluding Event::Lib, Qt and POE as the pure perl |
84 | event loop, which is also not very efficient. |
88 | adaptor should always succeed) in the order given. The first one that can |
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89 | be successfully loaded will be used. If, after this, still none could be |
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90 | found, AnyEvent will fall back to a pure-perl event loop, which is not |
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91 | very efficient, but should work everywhere. |
85 | |
92 | |
86 | Because AnyEvent first checks for modules that are already loaded, loading |
93 | Because AnyEvent first checks for modules that are already loaded, loading |
87 | an Event model explicitly before first using AnyEvent will likely make |
94 | an event model explicitly before first using AnyEvent will likely make |
88 | that model the default. For example: |
95 | that model the default. For example: |
89 | |
96 | |
90 | use Tk; |
97 | use Tk; |
91 | use AnyEvent; |
98 | use AnyEvent; |
92 | |
99 | |
93 | # .. AnyEvent will likely default to Tk |
100 | # .. AnyEvent will likely default to Tk |
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101 | |
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102 | The I<likely> means that, if any module loads another event model and |
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103 | starts using it, all bets are off. Maybe you should tell their authors to |
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104 | use AnyEvent so their modules work together with others seamlessly... |
94 | |
105 | |
95 | The pure-perl implementation of AnyEvent is called |
106 | The pure-perl implementation of AnyEvent is called |
96 | C<AnyEvent::Impl::Perl>. Like other event modules you can load it |
107 | C<AnyEvent::Impl::Perl>. Like other event modules you can load it |
97 | explicitly. |
108 | explicitly. |
98 | |
109 | |
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101 | AnyEvent has the central concept of a I<watcher>, which is an object that |
112 | AnyEvent has the central concept of a I<watcher>, which is an object that |
102 | stores relevant data for each kind of event you are waiting for, such as |
113 | stores relevant data for each kind of event you are waiting for, such as |
103 | the callback to call, the filehandle to watch, etc. |
114 | the callback to call, the filehandle to watch, etc. |
104 | |
115 | |
105 | These watchers are normal Perl objects with normal Perl lifetime. After |
116 | These watchers are normal Perl objects with normal Perl lifetime. After |
106 | creating a watcher it will immediately "watch" for events and invoke |
117 | creating a watcher it will immediately "watch" for events and invoke the |
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118 | callback when the event occurs (of course, only when the event model |
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119 | is in control). |
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120 | |
107 | the callback. To disable the watcher you have to destroy it (e.g. by |
121 | To disable the watcher you have to destroy it (e.g. by setting the |
108 | setting the variable that stores it to C<undef> or otherwise deleting all |
122 | variable you store it in to C<undef> or otherwise deleting all references |
109 | references to it). |
123 | to it). |
110 | |
124 | |
111 | All watchers are created by calling a method on the C<AnyEvent> class. |
125 | All watchers are created by calling a method on the C<AnyEvent> class. |
112 | |
126 | |
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127 | Many watchers either are used with "recursion" (repeating timers for |
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128 | example), or need to refer to their watcher object in other ways. |
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129 | |
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130 | An any way to achieve that is this pattern: |
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131 | |
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132 | my $w; $w = AnyEvent->type (arg => value ..., cb => sub { |
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133 | # you can use $w here, for example to undef it |
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134 | undef $w; |
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135 | }); |
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136 | |
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137 | Note that C<my $w; $w => combination. This is necessary because in Perl, |
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138 | my variables are only visible after the statement in which they are |
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139 | declared. |
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140 | |
113 | =head2 IO WATCHERS |
141 | =head2 IO WATCHERS |
114 | |
142 | |
115 | You can create I/O watcher by calling the C<< AnyEvent->io >> method with |
143 | You can create an I/O watcher by calling the C<< AnyEvent->io >> method |
116 | the following mandatory arguments: |
144 | with the following mandatory key-value pairs as arguments: |
117 | |
145 | |
118 | C<fh> the Perl I<filehandle> (not filedescriptor) to watch for |
146 | C<fh> the Perl I<file handle> (I<not> file descriptor) to watch for |
119 | events. C<poll> must be a string that is either C<r> or C<w>, that creates |
147 | events. C<poll> must be a string that is either C<r> or C<w>, which |
120 | a watcher waiting for "r"eadable or "w"ritable events. C<cb> the callback |
148 | creates a watcher waiting for "r"eadable or "w"ritable events, |
121 | to invoke everytime the filehandle becomes ready. |
149 | respectively. C<cb> is the callback to invoke each time the file handle |
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150 | becomes ready. |
122 | |
151 | |
123 | Only one io watcher per C<fh> and C<poll> combination is allowed (i.e. on |
152 | As long as the I/O watcher exists it will keep the file descriptor or a |
124 | a socket you can have one r + one w, not any more (limitation comes from |
153 | copy of it alive/open. |
125 | Tk - if you are sure you are not using Tk this limitation is gone). |
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126 | |
154 | |
127 | Filehandles will be kept alive, so as long as the watcher exists, the |
155 | It is not allowed to close a file handle as long as any watcher is active |
128 | filehandle exists, too. |
156 | on the underlying file descriptor. |
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157 | |
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158 | Some event loops issue spurious readyness notifications, so you should |
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159 | always use non-blocking calls when reading/writing from/to your file |
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160 | handles. |
129 | |
161 | |
130 | Example: |
162 | Example: |
131 | |
163 | |
132 | # wait for readability of STDIN, then read a line and disable the watcher |
164 | # wait for readability of STDIN, then read a line and disable the watcher |
133 | my $w; $w = AnyEvent->io (fh => \*STDIN, poll => 'r', cb => sub { |
165 | my $w; $w = AnyEvent->io (fh => \*STDIN, poll => 'r', cb => sub { |
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139 | =head2 TIME WATCHERS |
171 | =head2 TIME WATCHERS |
140 | |
172 | |
141 | You can create a time watcher by calling the C<< AnyEvent->timer >> |
173 | You can create a time watcher by calling the C<< AnyEvent->timer >> |
142 | method with the following mandatory arguments: |
174 | method with the following mandatory arguments: |
143 | |
175 | |
144 | C<after> after how many seconds (fractions are supported) should the timer |
176 | C<after> specifies after how many seconds (fractional values are |
145 | activate. C<cb> the callback to invoke. |
177 | supported) should the timer activate. C<cb> the callback to invoke in that |
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178 | case. |
146 | |
179 | |
147 | The timer callback will be invoked at most once: if you want a repeating |
180 | The timer callback will be invoked at most once: if you want a repeating |
148 | timer you have to create a new watcher (this is a limitation by both Tk |
181 | timer you have to create a new watcher (this is a limitation by both Tk |
149 | and Glib). |
182 | and Glib). |
150 | |
183 | |
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156 | }); |
189 | }); |
157 | |
190 | |
158 | # to cancel the timer: |
191 | # to cancel the timer: |
159 | undef $w; |
192 | undef $w; |
160 | |
193 | |
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194 | Example 2: |
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195 | |
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196 | # fire an event after 0.5 seconds, then roughly every second |
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197 | my $w; |
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198 | |
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199 | my $cb = sub { |
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200 | # cancel the old timer while creating a new one |
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201 | $w = AnyEvent->timer (after => 1, cb => $cb); |
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202 | }; |
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203 | |
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204 | # start the "loop" by creating the first watcher |
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205 | $w = AnyEvent->timer (after => 0.5, cb => $cb); |
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206 | |
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207 | =head3 TIMING ISSUES |
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208 | |
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209 | There are two ways to handle timers: based on real time (relative, "fire |
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210 | in 10 seconds") and based on wallclock time (absolute, "fire at 12 |
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211 | o'clock"). |
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212 | |
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213 | While most event loops expect timers to specified in a relative way, they |
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214 | use absolute time internally. This makes a difference when your clock |
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215 | "jumps", for example, when ntp decides to set your clock backwards from |
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216 | the wrong date of 2014-01-01 to 2008-01-01, a watcher that is supposed to |
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217 | fire "after" a second might actually take six years to finally fire. |
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218 | |
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219 | AnyEvent cannot compensate for this. The only event loop that is conscious |
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220 | about these issues is L<EV>, which offers both relative (ev_timer, based |
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221 | on true relative time) and absolute (ev_periodic, based on wallclock time) |
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222 | timers. |
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223 | |
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224 | AnyEvent always prefers relative timers, if available, matching the |
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225 | AnyEvent API. |
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226 | |
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227 | =head2 SIGNAL WATCHERS |
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228 | |
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229 | You can watch for signals using a signal watcher, C<signal> is the signal |
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230 | I<name> without any C<SIG> prefix, C<cb> is the Perl callback to |
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231 | be invoked whenever a signal occurs. |
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232 | |
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233 | Multiple signal occurances can be clumped together into one callback |
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234 | invocation, and callback invocation will be synchronous. synchronous means |
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235 | that it might take a while until the signal gets handled by the process, |
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236 | but it is guarenteed not to interrupt any other callbacks. |
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237 | |
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238 | The main advantage of using these watchers is that you can share a signal |
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239 | between multiple watchers. |
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240 | |
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241 | This watcher might use C<%SIG>, so programs overwriting those signals |
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242 | directly will likely not work correctly. |
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243 | |
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244 | Example: exit on SIGINT |
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245 | |
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246 | my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 }); |
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247 | |
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248 | =head2 CHILD PROCESS WATCHERS |
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249 | |
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250 | You can also watch on a child process exit and catch its exit status. |
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251 | |
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252 | The child process is specified by the C<pid> argument (if set to C<0>, it |
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253 | watches for any child process exit). The watcher will trigger as often |
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254 | as status change for the child are received. This works by installing a |
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255 | signal handler for C<SIGCHLD>. The callback will be called with the pid |
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256 | and exit status (as returned by waitpid). |
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257 | |
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258 | Example: wait for pid 1333 |
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259 | |
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260 | my $w = AnyEvent->child ( |
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261 | pid => 1333, |
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262 | cb => sub { |
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263 | my ($pid, $status) = @_; |
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264 | warn "pid $pid exited with status $status"; |
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265 | }, |
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266 | ); |
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267 | |
161 | =head2 CONDITION WATCHERS |
268 | =head2 CONDITION VARIABLES |
162 | |
269 | |
163 | Condition watchers can be created by calling the C<< AnyEvent->condvar >> |
270 | Condition variables can be created by calling the C<< AnyEvent->condvar >> |
164 | method without any arguments. |
271 | method without any arguments. |
165 | |
272 | |
166 | A condition watcher watches for a condition - precisely that the C<< |
273 | A condition variable waits for a condition - precisely that the C<< |
167 | ->broadcast >> method has been called. |
274 | ->broadcast >> method has been called. |
168 | |
275 | |
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276 | They are very useful to signal that a condition has been fulfilled, for |
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277 | example, if you write a module that does asynchronous http requests, |
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278 | then a condition variable would be the ideal candidate to signal the |
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279 | availability of results. |
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280 | |
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281 | You can also use condition variables to block your main program until |
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282 | an event occurs - for example, you could C<< ->wait >> in your main |
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283 | program until the user clicks the Quit button in your app, which would C<< |
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284 | ->broadcast >> the "quit" event. |
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285 | |
169 | Note that condition watchers recurse into the event loop - if you have |
286 | Note that condition variables recurse into the event loop - if you have |
170 | two watchers that call C<< ->wait >> in a round-robbin fashion, you |
287 | two pirces of code that call C<< ->wait >> in a round-robbin fashion, you |
171 | lose. Therefore, condition watchers are good to export to your caller, but |
288 | lose. Therefore, condition variables are good to export to your caller, but |
172 | you should avoid making a blocking wait, at least in callbacks, as this |
289 | you should avoid making a blocking wait yourself, at least in callbacks, |
173 | usually asks for trouble. |
290 | as this asks for trouble. |
174 | |
291 | |
175 | The watcher has only two methods: |
292 | This object has two methods: |
176 | |
293 | |
177 | =over 4 |
294 | =over 4 |
178 | |
295 | |
179 | =item $cv->wait |
296 | =item $cv->wait |
180 | |
297 | |
181 | Wait (blocking if necessary) until the C<< ->broadcast >> method has been |
298 | Wait (blocking if necessary) until the C<< ->broadcast >> method has been |
182 | called on c<$cv>, while servicing other watchers normally. |
299 | called on c<$cv>, while servicing other watchers normally. |
183 | |
300 | |
184 | Not all event models support a blocking wait - some die in that case, so |
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185 | if you are using this from a module, never require a blocking wait, but |
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186 | let the caller decide wether the call will block or not (for example, |
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187 | by coupling condition variables with some kind of request results and |
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188 | supporting callbacks so the caller knows that getting the result will not |
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189 | block, while still suppporting blockign waits if the caller so desires). |
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190 | |
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191 | You can only wait once on a condition - additional calls will return |
301 | You can only wait once on a condition - additional calls will return |
192 | immediately. |
302 | immediately. |
193 | |
303 | |
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304 | Not all event models support a blocking wait - some die in that case |
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305 | (programs might want to do that to stay interactive), so I<if you are |
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306 | using this from a module, never require a blocking wait>, but let the |
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307 | caller decide whether the call will block or not (for example, by coupling |
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308 | condition variables with some kind of request results and supporting |
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309 | callbacks so the caller knows that getting the result will not block, |
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310 | while still suppporting blocking waits if the caller so desires). |
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311 | |
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312 | Another reason I<never> to C<< ->wait >> in a module is that you cannot |
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313 | sensibly have two C<< ->wait >>'s in parallel, as that would require |
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314 | multiple interpreters or coroutines/threads, none of which C<AnyEvent> |
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315 | can supply (the coroutine-aware backends L<AnyEvent::Impl::CoroEV> and |
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316 | L<AnyEvent::Impl::CoroEvent> explicitly support concurrent C<< ->wait >>'s |
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317 | from different coroutines, however). |
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318 | |
194 | =item $cv->broadcast |
319 | =item $cv->broadcast |
195 | |
320 | |
196 | Flag the condition as ready - a running C<< ->wait >> and all further |
321 | Flag the condition as ready - a running C<< ->wait >> and all further |
197 | calls to C<wait> will return after this method has been called. If nobody |
322 | calls to C<wait> will (eventually) return after this method has been |
198 | is waiting the broadcast will be remembered.. |
323 | called. If nobody is waiting the broadcast will be remembered.. |
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324 | |
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325 | =back |
199 | |
326 | |
200 | Example: |
327 | Example: |
201 | |
328 | |
202 | # wait till the result is ready |
329 | # wait till the result is ready |
203 | my $result_ready = AnyEvent->condvar; |
330 | my $result_ready = AnyEvent->condvar; |
204 | |
331 | |
205 | # do something such as adding a timer |
332 | # do something such as adding a timer |
206 | # or socket watcher the calls $result_ready->broadcast |
333 | # or socket watcher the calls $result_ready->broadcast |
207 | # when the "result" is ready. |
334 | # when the "result" is ready. |
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335 | # in this case, we simply use a timer: |
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336 | my $w = AnyEvent->timer ( |
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337 | after => 1, |
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338 | cb => sub { $result_ready->broadcast }, |
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339 | ); |
208 | |
340 | |
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341 | # this "blocks" (while handling events) till the watcher |
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342 | # calls broadcast |
209 | $result_ready->wait; |
343 | $result_ready->wait; |
210 | |
344 | |
211 | =back |
345 | =head1 GLOBAL VARIABLES AND FUNCTIONS |
212 | |
|
|
213 | =head2 SIGNAL WATCHERS |
|
|
214 | |
|
|
215 | You can listen for signals using a signal watcher, C<signal> is the signal |
|
|
216 | I<name> without any C<SIG> prefix. Multiple signals events can be clumped |
|
|
217 | together into one callback invocation, and callback invocation might or |
|
|
218 | might not be asynchronous. |
|
|
219 | |
|
|
220 | These watchers might use C<%SIG>, so programs overwriting those signals |
|
|
221 | directly will likely not work correctly. |
|
|
222 | |
|
|
223 | Example: exit on SIGINT |
|
|
224 | |
|
|
225 | my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 }); |
|
|
226 | |
|
|
227 | =head2 CHILD PROCESS WATCHERS |
|
|
228 | |
|
|
229 | You can also listen for the status of a child process specified by the |
|
|
230 | C<pid> argument (or any child if the pid argument is 0). The watcher will |
|
|
231 | trigger as often as status change for the child are received. This works |
|
|
232 | by installing a signal handler for C<SIGCHLD>. The callback will be called with |
|
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233 | the pid and exit status (as returned by waitpid). |
|
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234 | |
|
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235 | Example: wait for pid 1333 |
|
|
236 | |
|
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237 | my $w = AnyEvent->child (pid => 1333, cb => sub { warn "exit status $?" }); |
|
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238 | |
|
|
239 | =head1 GLOBALS |
|
|
240 | |
346 | |
241 | =over 4 |
347 | =over 4 |
242 | |
348 | |
243 | =item $AnyEvent::MODEL |
349 | =item $AnyEvent::MODEL |
244 | |
350 | |
… | |
… | |
249 | AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode>). |
355 | AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode>). |
250 | |
356 | |
251 | The known classes so far are: |
357 | The known classes so far are: |
252 | |
358 | |
253 | AnyEvent::Impl::CoroEV based on Coro::EV, best choice. |
359 | AnyEvent::Impl::CoroEV based on Coro::EV, best choice. |
254 | AnyEvent::Impl::EV based on EV (an interface to libev, also best choice). |
|
|
255 | AnyEvent::Impl::CoroEvent based on Coro::Event, second best choice. |
360 | AnyEvent::Impl::CoroEvent based on Coro::Event, second best choice. |
|
|
361 | AnyEvent::Impl::EV based on EV (an interface to libev, best choice). |
256 | AnyEvent::Impl::Event based on Event, also second best choice :) |
362 | AnyEvent::Impl::Event based on Event, second best choice. |
257 | AnyEvent::Impl::Glib based on Glib, second-best choice. |
363 | AnyEvent::Impl::Glib based on Glib, third-best choice. |
258 | AnyEvent::Impl::Tk based on Tk, very bad choice. |
364 | AnyEvent::Impl::Tk based on Tk, very bad choice. |
259 | AnyEvent::Impl::Perl pure-perl implementation, inefficient. |
365 | AnyEvent::Impl::Perl pure-perl implementation, inefficient but portable. |
|
|
366 | AnyEvent::Impl::Qt based on Qt, cannot be autoprobed (see its docs). |
|
|
367 | AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse. |
|
|
368 | AnyEvent::Impl::POE based on POE, not generic enough for full support. |
|
|
369 | |
|
|
370 | There is no support for WxWidgets, as WxWidgets has no support for |
|
|
371 | watching file handles. However, you can use WxWidgets through the |
|
|
372 | POE Adaptor, as POE has a Wx backend that simply polls 20 times per |
|
|
373 | second, which was considered to be too horrible to even consider for |
|
|
374 | AnyEvent. Likewise, other POE backends can be used by Anyevent by using |
|
|
375 | it's adaptor. |
260 | |
376 | |
261 | =item AnyEvent::detect |
377 | =item AnyEvent::detect |
262 | |
378 | |
263 | Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model if |
379 | Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model |
264 | necessary. You should only call this function right before you would have |
380 | if necessary. You should only call this function right before you would |
265 | created an AnyEvent watcher anyway, that is, very late at runtime. |
381 | have created an AnyEvent watcher anyway, that is, as late as possible at |
|
|
382 | runtime. |
266 | |
383 | |
267 | =back |
384 | =back |
268 | |
385 | |
269 | =head1 WHAT TO DO IN A MODULE |
386 | =head1 WHAT TO DO IN A MODULE |
270 | |
387 | |
271 | As a module author, you should "use AnyEvent" and call AnyEvent methods |
388 | As a module author, you should C<use AnyEvent> and call AnyEvent methods |
272 | freely, but you should not load a specific event module or rely on it. |
389 | freely, but you should not load a specific event module or rely on it. |
273 | |
390 | |
274 | Be careful when you create watchers in the module body - Anyevent will |
391 | Be careful when you create watchers in the module body - AnyEvent will |
275 | decide which event module to use as soon as the first method is called, so |
392 | decide which event module to use as soon as the first method is called, so |
276 | by calling AnyEvent in your module body you force the user of your module |
393 | by calling AnyEvent in your module body you force the user of your module |
277 | to load the event module first. |
394 | to load the event module first. |
278 | |
395 | |
|
|
396 | Never call C<< ->wait >> on a condition variable unless you I<know> that |
|
|
397 | the C<< ->broadcast >> method has been called on it already. This is |
|
|
398 | because it will stall the whole program, and the whole point of using |
|
|
399 | events is to stay interactive. |
|
|
400 | |
|
|
401 | It is fine, however, to call C<< ->wait >> when the user of your module |
|
|
402 | requests it (i.e. if you create a http request object ad have a method |
|
|
403 | called C<results> that returns the results, it should call C<< ->wait >> |
|
|
404 | freely, as the user of your module knows what she is doing. always). |
|
|
405 | |
279 | =head1 WHAT TO DO IN THE MAIN PROGRAM |
406 | =head1 WHAT TO DO IN THE MAIN PROGRAM |
280 | |
407 | |
281 | There will always be a single main program - the only place that should |
408 | There will always be a single main program - the only place that should |
282 | dictate which event model to use. |
409 | dictate which event model to use. |
283 | |
410 | |
284 | If it doesn't care, it can just "use AnyEvent" and use it itself, or not |
411 | If it doesn't care, it can just "use AnyEvent" and use it itself, or not |
285 | do anything special and let AnyEvent decide which implementation to chose. |
412 | do anything special (it does not need to be event-based) and let AnyEvent |
|
|
413 | decide which implementation to chose if some module relies on it. |
286 | |
414 | |
287 | If the main program relies on a specific event model (for example, in Gtk2 |
415 | If the main program relies on a specific event model. For example, in |
288 | programs you have to rely on either Glib or Glib::Event), you should load |
416 | Gtk2 programs you have to rely on the Glib module. You should load the |
289 | it before loading AnyEvent or any module that uses it, generally, as early |
417 | event module before loading AnyEvent or any module that uses it: generally |
290 | as possible. The reason is that modules might create watchers when they |
418 | speaking, you should load it as early as possible. The reason is that |
291 | are loaded, and AnyEvent will decide on the event model to use as soon as |
419 | modules might create watchers when they are loaded, and AnyEvent will |
292 | it creates watchers, and it might chose the wrong one unless you load the |
420 | decide on the event model to use as soon as it creates watchers, and it |
293 | correct one yourself. |
421 | might chose the wrong one unless you load the correct one yourself. |
294 | |
422 | |
295 | You can chose to use a rather inefficient pure-perl implementation by |
423 | You can chose to use a rather inefficient pure-perl implementation by |
296 | loading the C<AnyEvent::Impl::Perl> module, but letting AnyEvent chose is |
424 | loading the C<AnyEvent::Impl::Perl> module, which gives you similar |
297 | generally better. |
425 | behaviour everywhere, but letting AnyEvent chose is generally better. |
298 | |
426 | |
299 | =cut |
427 | =cut |
300 | |
428 | |
301 | package AnyEvent; |
429 | package AnyEvent; |
302 | |
430 | |
303 | no warnings; |
431 | no warnings; |
304 | use strict; |
432 | use strict; |
305 | |
433 | |
306 | use Carp; |
434 | use Carp; |
307 | |
435 | |
308 | our $VERSION = '3.0'; |
436 | our $VERSION = '3.2'; |
309 | our $MODEL; |
437 | our $MODEL; |
310 | |
438 | |
311 | our $AUTOLOAD; |
439 | our $AUTOLOAD; |
312 | our @ISA; |
440 | our @ISA; |
313 | |
441 | |
… | |
… | |
315 | |
443 | |
316 | our @REGISTRY; |
444 | our @REGISTRY; |
317 | |
445 | |
318 | my @models = ( |
446 | my @models = ( |
319 | [Coro::EV:: => AnyEvent::Impl::CoroEV::], |
447 | [Coro::EV:: => AnyEvent::Impl::CoroEV::], |
|
|
448 | [Coro::Event:: => AnyEvent::Impl::CoroEvent::], |
320 | [EV:: => AnyEvent::Impl::EV::], |
449 | [EV:: => AnyEvent::Impl::EV::], |
321 | [Coro::Event:: => AnyEvent::Impl::CoroEvent::], |
|
|
322 | [Event:: => AnyEvent::Impl::Event::], |
450 | [Event:: => AnyEvent::Impl::Event::], |
323 | [Glib:: => AnyEvent::Impl::Glib::], |
451 | [Glib:: => AnyEvent::Impl::Glib::], |
324 | [Tk:: => AnyEvent::Impl::Tk::], |
452 | [Tk:: => AnyEvent::Impl::Tk::], |
325 | [AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl::], |
453 | [AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl::], |
|
|
454 | # everything below here will not be autoprobed as the pureperl backend should work everywhere |
|
|
455 | [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy |
|
|
456 | [Qt:: => AnyEvent::Impl::Qt::], # requires special main program |
|
|
457 | [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza |
326 | ); |
458 | ); |
327 | |
459 | |
328 | our %method = map +($_ => 1), qw(io timer condvar broadcast wait signal one_event DESTROY); |
460 | our %method = map +($_ => 1), qw(io timer signal child condvar broadcast wait one_event DESTROY); |
329 | |
461 | |
330 | sub detect() { |
462 | sub detect() { |
331 | unless ($MODEL) { |
463 | unless ($MODEL) { |
332 | no strict 'refs'; |
464 | no strict 'refs'; |
333 | |
465 | |
|
|
466 | if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) { |
|
|
467 | my $model = "AnyEvent::Impl::$1"; |
|
|
468 | if (eval "require $model") { |
|
|
469 | $MODEL = $model; |
|
|
470 | warn "AnyEvent: loaded model '$model' (forced by \$PERL_ANYEVENT_MODEL), using it.\n" if $verbose > 1; |
|
|
471 | } else { |
|
|
472 | warn "AnyEvent: unable to load model '$model' (from \$PERL_ANYEVENT_MODEL):\n$@" if $verbose; |
|
|
473 | } |
|
|
474 | } |
|
|
475 | |
334 | # check for already loaded models |
476 | # check for already loaded models |
|
|
477 | unless ($MODEL) { |
335 | for (@REGISTRY, @models) { |
478 | for (@REGISTRY, @models) { |
336 | my ($package, $model) = @$_; |
479 | my ($package, $model) = @$_; |
337 | if (${"$package\::VERSION"} > 0) { |
480 | if (${"$package\::VERSION"} > 0) { |
338 | if (eval "require $model") { |
481 | if (eval "require $model") { |
339 | $MODEL = $model; |
482 | $MODEL = $model; |
340 | warn "AnyEvent: found model '$model', using it.\n" if $verbose > 1; |
483 | warn "AnyEvent: autodetected model '$model', using it.\n" if $verbose > 1; |
341 | last; |
484 | last; |
|
|
485 | } |
342 | } |
486 | } |
343 | } |
487 | } |
344 | } |
|
|
345 | |
488 | |
346 | unless ($MODEL) { |
489 | unless ($MODEL) { |
347 | # try to load a model |
490 | # try to load a model |
348 | |
491 | |
349 | for (@REGISTRY, @models) { |
492 | for (@REGISTRY, @models) { |
350 | my ($package, $model) = @$_; |
493 | my ($package, $model) = @$_; |
351 | if (eval "require $package" |
494 | if (eval "require $package" |
352 | and ${"$package\::VERSION"} > 0 |
495 | and ${"$package\::VERSION"} > 0 |
353 | and eval "require $model") { |
496 | and eval "require $model") { |
354 | $MODEL = $model; |
497 | $MODEL = $model; |
355 | warn "AnyEvent: autoprobed and loaded model '$model', using it.\n" if $verbose > 1; |
498 | warn "AnyEvent: autoprobed model '$model', using it.\n" if $verbose > 1; |
356 | last; |
499 | last; |
|
|
500 | } |
357 | } |
501 | } |
|
|
502 | |
|
|
503 | $MODEL |
|
|
504 | or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV (or Coro+EV), Event (or Coro+Event) or Glib."; |
358 | } |
505 | } |
359 | |
|
|
360 | $MODEL |
|
|
361 | or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV (or Coro+EV), Event (or Coro+Event), Glib or Tk."; |
|
|
362 | } |
506 | } |
363 | |
507 | |
364 | unshift @ISA, $MODEL; |
508 | unshift @ISA, $MODEL; |
365 | push @{"$MODEL\::ISA"}, "AnyEvent::Base"; |
509 | push @{"$MODEL\::ISA"}, "AnyEvent::Base"; |
366 | } |
510 | } |
… | |
… | |
477 | undef $CHLD_W unless keys %PID_CB; |
621 | undef $CHLD_W unless keys %PID_CB; |
478 | } |
622 | } |
479 | |
623 | |
480 | =head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE |
624 | =head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE |
481 | |
625 | |
|
|
626 | This is an advanced topic that you do not normally need to use AnyEvent in |
|
|
627 | a module. This section is only of use to event loop authors who want to |
|
|
628 | provide AnyEvent compatibility. |
|
|
629 | |
482 | If you need to support another event library which isn't directly |
630 | If you need to support another event library which isn't directly |
483 | supported by AnyEvent, you can supply your own interface to it by |
631 | supported by AnyEvent, you can supply your own interface to it by |
484 | pushing, before the first watcher gets created, the package name of |
632 | pushing, before the first watcher gets created, the package name of |
485 | the event module and the package name of the interface to use onto |
633 | the event module and the package name of the interface to use onto |
486 | C<@AnyEvent::REGISTRY>. You can do that before and even without loading |
634 | C<@AnyEvent::REGISTRY>. You can do that before and even without loading |
487 | AnyEvent. |
635 | AnyEvent, so it is reasonably cheap. |
488 | |
636 | |
489 | Example: |
637 | Example: |
490 | |
638 | |
491 | push @AnyEvent::REGISTRY, [urxvt => urxvt::anyevent::]; |
639 | push @AnyEvent::REGISTRY, [urxvt => urxvt::anyevent::]; |
492 | |
640 | |
493 | This tells AnyEvent to (literally) use the C<urxvt::anyevent::> |
641 | This tells AnyEvent to (literally) use the C<urxvt::anyevent::> |
494 | package/class when it finds the C<urxvt> package/module is loaded. When |
642 | package/class when it finds the C<urxvt> package/module is already loaded. |
|
|
643 | |
495 | AnyEvent is loaded and asked to find a suitable event model, it will |
644 | When AnyEvent is loaded and asked to find a suitable event model, it |
496 | first check for the presence of urxvt. |
645 | will first check for the presence of urxvt by trying to C<use> the |
|
|
646 | C<urxvt::anyevent> module. |
497 | |
647 | |
498 | The class should provide implementations for all watcher types (see |
648 | The class should provide implementations for all watcher types. See |
499 | L<AnyEvent::Impl::Event> (source code), L<AnyEvent::Impl::Glib> |
649 | L<AnyEvent::Impl::EV> (source code), L<AnyEvent::Impl::Glib> (Source code) |
500 | (Source code) and so on for actual examples, use C<perldoc -m |
650 | and so on for actual examples. Use C<perldoc -m AnyEvent::Impl::Glib> to |
501 | AnyEvent::Impl::Glib> to see the sources). |
651 | see the sources. |
502 | |
652 | |
|
|
653 | If you don't provide C<signal> and C<child> watchers than AnyEvent will |
|
|
654 | provide suitable (hopefully) replacements. |
|
|
655 | |
503 | The above isn't fictitious, the I<rxvt-unicode> (a.k.a. urxvt) |
656 | The above example isn't fictitious, the I<rxvt-unicode> (a.k.a. urxvt) |
504 | uses the above line as-is. An interface isn't included in AnyEvent |
657 | terminal emulator uses the above line as-is. An interface isn't included |
505 | because it doesn't make sense outside the embedded interpreter inside |
658 | in AnyEvent because it doesn't make sense outside the embedded interpreter |
506 | I<rxvt-unicode>, and it is updated and maintained as part of the |
659 | inside I<rxvt-unicode>, and it is updated and maintained as part of the |
507 | I<rxvt-unicode> distribution. |
660 | I<rxvt-unicode> distribution. |
508 | |
661 | |
509 | I<rxvt-unicode> also cheats a bit by not providing blocking access to |
662 | I<rxvt-unicode> also cheats a bit by not providing blocking access to |
510 | condition variables: code blocking while waiting for a condition will |
663 | condition variables: code blocking while waiting for a condition will |
511 | C<die>. This still works with most modules/usages, and blocking calls must |
664 | C<die>. This still works with most modules/usages, and blocking calls must |
512 | not be in an interactive application, so it makes sense. |
665 | not be done in an interactive application, so it makes sense. |
513 | |
666 | |
514 | =head1 ENVIRONMENT VARIABLES |
667 | =head1 ENVIRONMENT VARIABLES |
515 | |
668 | |
516 | The following environment variables are used by this module: |
669 | The following environment variables are used by this module: |
517 | |
670 | |
518 | C<PERL_ANYEVENT_VERBOSE> when set to C<2> or higher, reports which event |
671 | =over 4 |
519 | model gets used. |
|
|
520 | |
672 | |
|
|
673 | =item C<PERL_ANYEVENT_VERBOSE> |
|
|
674 | |
|
|
675 | By default, AnyEvent will be completely silent except in fatal |
|
|
676 | conditions. You can set this environment variable to make AnyEvent more |
|
|
677 | talkative. |
|
|
678 | |
|
|
679 | When set to C<1> or higher, causes AnyEvent to warn about unexpected |
|
|
680 | conditions, such as not being able to load the event model specified by |
|
|
681 | C<PERL_ANYEVENT_MODEL>. |
|
|
682 | |
|
|
683 | When set to C<2> or higher, cause AnyEvent to report to STDERR which event |
|
|
684 | model it chooses. |
|
|
685 | |
|
|
686 | =item C<PERL_ANYEVENT_MODEL> |
|
|
687 | |
|
|
688 | This can be used to specify the event model to be used by AnyEvent, before |
|
|
689 | autodetection and -probing kicks in. It must be a string consisting |
|
|
690 | entirely of ASCII letters. The string C<AnyEvent::Impl::> gets prepended |
|
|
691 | and the resulting module name is loaded and if the load was successful, |
|
|
692 | used as event model. If it fails to load AnyEvent will proceed with |
|
|
693 | autodetection and -probing. |
|
|
694 | |
|
|
695 | This functionality might change in future versions. |
|
|
696 | |
|
|
697 | For example, to force the pure perl model (L<AnyEvent::Impl::Perl>) you |
|
|
698 | could start your program like this: |
|
|
699 | |
|
|
700 | PERL_ANYEVENT_MODEL=Perl perl ... |
|
|
701 | |
|
|
702 | =back |
|
|
703 | |
521 | =head1 EXAMPLE |
704 | =head1 EXAMPLE PROGRAM |
522 | |
705 | |
523 | The following program uses an io watcher to read data from stdin, a timer |
706 | The following program uses an IO watcher to read data from STDIN, a timer |
524 | to display a message once per second, and a condvar to exit the program |
707 | to display a message once per second, and a condition variable to quit the |
525 | when the user enters quit: |
708 | program when the user enters quit: |
526 | |
709 | |
527 | use AnyEvent; |
710 | use AnyEvent; |
528 | |
711 | |
529 | my $cv = AnyEvent->condvar; |
712 | my $cv = AnyEvent->condvar; |
530 | |
713 | |
531 | my $io_watcher = AnyEvent->io (fh => \*STDIN, poll => 'r', cb => sub { |
714 | my $io_watcher = AnyEvent->io ( |
|
|
715 | fh => \*STDIN, |
|
|
716 | poll => 'r', |
|
|
717 | cb => sub { |
532 | warn "io event <$_[0]>\n"; # will always output <r> |
718 | warn "io event <$_[0]>\n"; # will always output <r> |
533 | chomp (my $input = <STDIN>); # read a line |
719 | chomp (my $input = <STDIN>); # read a line |
534 | warn "read: $input\n"; # output what has been read |
720 | warn "read: $input\n"; # output what has been read |
535 | $cv->broadcast if $input =~ /^q/i; # quit program if /^q/i |
721 | $cv->broadcast if $input =~ /^q/i; # quit program if /^q/i |
|
|
722 | }, |
536 | }); |
723 | ); |
537 | |
724 | |
538 | my $time_watcher; # can only be used once |
725 | my $time_watcher; # can only be used once |
539 | |
726 | |
540 | sub new_timer { |
727 | sub new_timer { |
541 | $timer = AnyEvent->timer (after => 1, cb => sub { |
728 | $timer = AnyEvent->timer (after => 1, cb => sub { |
… | |
… | |
623 | $txn->{finished}->wait; |
810 | $txn->{finished}->wait; |
624 | return $txn->{result}; |
811 | return $txn->{result}; |
625 | |
812 | |
626 | The actual code goes further and collects all errors (C<die>s, exceptions) |
813 | The actual code goes further and collects all errors (C<die>s, exceptions) |
627 | that occured during request processing. The C<result> method detects |
814 | that occured during request processing. The C<result> method detects |
628 | wether an exception as thrown (it is stored inside the $txn object) |
815 | whether an exception as thrown (it is stored inside the $txn object) |
629 | and just throws the exception, which means connection errors and other |
816 | and just throws the exception, which means connection errors and other |
630 | problems get reported tot he code that tries to use the result, not in a |
817 | problems get reported tot he code that tries to use the result, not in a |
631 | random callback. |
818 | random callback. |
632 | |
819 | |
633 | All of this enables the following usage styles: |
820 | All of this enables the following usage styles: |
634 | |
821 | |
635 | 1. Blocking: |
822 | 1. Blocking: |
636 | |
823 | |
637 | my $data = $fcp->client_get ($url); |
824 | my $data = $fcp->client_get ($url); |
638 | |
825 | |
639 | 2. Blocking, but parallelizing: |
826 | 2. Blocking, but running in parallel: |
640 | |
827 | |
641 | my @datas = map $_->result, |
828 | my @datas = map $_->result, |
642 | map $fcp->txn_client_get ($_), |
829 | map $fcp->txn_client_get ($_), |
643 | @urls; |
830 | @urls; |
644 | |
831 | |
645 | Both blocking examples work without the module user having to know |
832 | Both blocking examples work without the module user having to know |
646 | anything about events. |
833 | anything about events. |
647 | |
834 | |
648 | 3a. Event-based in a main program, using any support Event module: |
835 | 3a. Event-based in a main program, using any supported event module: |
649 | |
836 | |
650 | use Event; |
837 | use EV; |
651 | |
838 | |
652 | $fcp->txn_client_get ($url)->cb (sub { |
839 | $fcp->txn_client_get ($url)->cb (sub { |
653 | my $txn = shift; |
840 | my $txn = shift; |
654 | my $data = $txn->result; |
841 | my $data = $txn->result; |
655 | ... |
842 | ... |
656 | }); |
843 | }); |
657 | |
844 | |
658 | Event::loop; |
845 | EV::loop; |
659 | |
846 | |
660 | 3b. The module user could use AnyEvent, too: |
847 | 3b. The module user could use AnyEvent, too: |
661 | |
848 | |
662 | use AnyEvent; |
849 | use AnyEvent; |
663 | |
850 | |
… | |
… | |
668 | $quit->broadcast; |
855 | $quit->broadcast; |
669 | }); |
856 | }); |
670 | |
857 | |
671 | $quit->wait; |
858 | $quit->wait; |
672 | |
859 | |
|
|
860 | =head1 FORK |
|
|
861 | |
|
|
862 | Most event libraries are not fork-safe. The ones who are usually are |
|
|
863 | because they are so inefficient. Only L<EV> is fully fork-aware. |
|
|
864 | |
|
|
865 | If you have to fork, you must either do so I<before> creating your first |
|
|
866 | watcher OR you must not use AnyEvent at all in the child. |
|
|
867 | |
|
|
868 | =head1 SECURITY CONSIDERATIONS |
|
|
869 | |
|
|
870 | AnyEvent can be forced to load any event model via |
|
|
871 | $ENV{PERL_ANYEVENT_MODEL}. While this cannot (to my knowledge) be used to |
|
|
872 | execute arbitrary code or directly gain access, it can easily be used to |
|
|
873 | make the program hang or malfunction in subtle ways, as AnyEvent watchers |
|
|
874 | will not be active when the program uses a different event model than |
|
|
875 | specified in the variable. |
|
|
876 | |
|
|
877 | You can make AnyEvent completely ignore this variable by deleting it |
|
|
878 | before the first watcher gets created, e.g. with a C<BEGIN> block: |
|
|
879 | |
|
|
880 | BEGIN { delete $ENV{PERL_ANYEVENT_MODEL} } |
|
|
881 | |
|
|
882 | use AnyEvent; |
|
|
883 | |
673 | =head1 SEE ALSO |
884 | =head1 SEE ALSO |
674 | |
885 | |
675 | Event modules: L<Coro::Event>, L<Coro>, L<Event>, L<Glib::Event>, L<Glib>. |
886 | Event modules: L<Coro::EV>, L<EV>, L<EV::Glib>, L<Glib::EV>, |
|
|
887 | L<Coro::Event>, L<Event>, L<Glib::Event>, L<Glib>, L<Coro>, L<Tk>, |
|
|
888 | L<Event::Lib>, L<Qt>, L<POE>. |
676 | |
889 | |
|
|
890 | Implementations: L<AnyEvent::Impl::CoroEV>, L<AnyEvent::Impl::EV>, |
677 | Implementations: L<AnyEvent::Impl::Coro>, L<AnyEvent::Impl::Event>, L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>. |
891 | L<AnyEvent::Impl::CoroEvent>, L<AnyEvent::Impl::Event>, L<AnyEvent::Impl::Glib>, |
|
|
892 | L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>, L<AnyEvent::Impl::EventLib>, |
|
|
893 | L<AnyEvent::Impl::Qt>, L<AnyEvent::Impl::POE>. |
678 | |
894 | |
679 | Nontrivial usage example: L<Net::FCP>. |
895 | Nontrivial usage examples: L<Net::FCP>, L<Net::XMPP2>. |
680 | |
896 | |
681 | =head1 |
897 | =head1 AUTHOR |
|
|
898 | |
|
|
899 | Marc Lehmann <schmorp@schmorp.de> |
|
|
900 | http://home.schmorp.de/ |
682 | |
901 | |
683 | =cut |
902 | =cut |
684 | |
903 | |
685 | 1 |
904 | 1 |
686 | |
905 | |