1Net::DBus::Reactor(3) User Contributed Perl DocumentationNet::DBus::Reactor(3)
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6 Net::DBus::Reactor - application event loop
7
9 Create and run an event loop:
10 use Net::DBus::Reactor;
12 my $reactor = Net::DBus::Reactor->main();
13 $reactor->run();
15 Manage some file handlers
17 $reactor->add_read($fd,
19 Net::DBus::Callback->new(method => sub {
20 my $fd = shift;
21 ...read some data...
22 }, args => [$fd]);
23 $reactor->add_write($fd,
25 Net::DBus::Callback->new(method => sub {
26 my $fd = shift;
27 ...write some data...
28 }, args => [$fd]);
29 Temporarily (dis⎪en)able a handle
31 # Disable
33 $reactor->toggle_read($fd, 0);
34 # Enable
35 $reactor->toggle_read($fd, 1);
36 Permanently remove a handle
38 $reactor->remove_read($fd);
40 Manage a regular timeout every 100 milliseconds
42 my $timer = $reactor->add_timeout(100,
44 Net::DBus::Callback->new(
45 method => sub {
46 ...process the alarm...
47 }));
48 Temporarily (dis⎪en)able a timer
50 # Disable
52 $reactor->toggle_timeout($timer, 0);
53 # Enable
54 $reactor->toggle_timeout($timer, 1);
55 Permanently remove a timer
57 $reactor->remove_timeout($timer);
59 Add a post-dispatch hook
61 my $hook = $reactor->add_hook(Net::DBus::Callback->new(
63 method => sub {
64 ... do some work...
65 }));
66 Remove a hook
68 $reactor->remove_hook($hook);
70
72 This class provides a general purpose event loop for the purposes of
73 multiplexing I/O events and timeouts in a single process. The underly‐
74 ing implementation is done using the select system call. File handles
75 can be registered for monitoring on read, write and exception
76 (out-of-band data) events. Timers can be registered to expire with a
77 periodic frequency. These are implemented using the timeout parameter
78 of the select system call. Since this parameter merely represents an
79 upper bound on the amount of time the select system call is allowed to
80 sleep, the actual period of the timers may vary. Under normal load this
81 variance is typically 10 milliseconds. Finally, hooks may be regis‐
82 tered which will be invoked on each iteration of the event loop (ie
83 after processing the file events, or timeouts indicated by the select
84 system call returning).
85
87 my $reactor = Net::DBus::Reactor->new();
88 Creates a new event loop ready for monitoring file handles, or gen‐
89 erating timeouts. Except in very unsual circumstances (examples of
90 which I can't think up) it is not neccessary or desriable to
91 explicitly create new reactor instances. Instead call the main
92 method to get a handle to the singleton instance.
93 $reactor = Net::DBus::Reactor->main;
95 Return a handle to the singleton instance of the reactor. This is
96 the recommended way of getting hold of a reactor, since it removes
97 the need for modules to pass around handles to their privately cre‐
98 ated reactors.
99 $reactor->manage($connection);
101 $reactor->manage($server);
102 Registers a "Net::DBus::Connection" or "Net::DBus::Server" object
103 for management by the event loop. This basically involves hooking
104 up the watch & timeout callbacks to the event loop. For connec‐
105 tions it will also register a hook to invoke the "dispatch" method
106 periodically.
107 $reactor->run();
109 Starts the event loop monitoring any registered file handles and
110 timeouts. At least one file handle, or timer must have been regis‐
111 tered prior to running the reactor, otherwise it will immediately
112 exit. The reactor will run until all registered file handles, or
113 timeouts have been removed, or disabled. The reactor can be explic‐
114 itly stopped by calling the "shutdown" method.
115 $reactor->shutdown();
117 Explicitly shutdown the reactor after pending events have been pro‐
118 cessed.
119 $reactor->step();
121 Perform one iteration of the event loop, going to sleep until an
122 event occurs on a registered file handle, or a timeout occurrs.
123 This method is generally not required in day-to-day use.
124 $reactor->add_read($fd, $callback[, $status]);
126 Registers a file handle for monitoring of read events. The $call‐
127 back parameter specifies an instance of the "Net::DBus::Callback"
128 object to invoke each time an event occurs. The optional $status
129 parameter is a boolean value to specify whether the watch is ini‐
130 tially enabled.
131 $reactor->add_write($fd, $callback[, $status]);
133 Registers a file handle for monitoring of write events. The $call‐
134 back parameter specifies an instance of the "Net::DBus::Callback"
135 object to invoke each time an event occurs. The optional $status
136 parameter is a boolean value to specify whether the watch is ini‐
137 tially enabled.
138 $reactor->add_exception($fd, $callback[, $status]);
140 Registers a file handle for monitoring of exception events. The
141 $callback parameter specifies an instance of the "Net::DBus::Call‐
142 back" object to invoke each time an event occurs. The optional
143 $status parameter is a boolean value to specify whether the watch
144 is initially enabled.
145 my $id = $reactor->add_timeout($interval, $callback, $status);
147 Registers a new timeout to expire every $interval milliseconds. The
148 $callback parameter specifies an instance of the "Net::DBus::Call‐
149 back" object to invoke each time the timeout expires. The optional
150 $status parameter is a boolean value to specify whether the timeout
151 is initially enabled. The return parameter is a unique identifier
152 which can be used to later remove or disable the timeout.
153 $reactor->remove_timeout($id);
155 Removes a previously registered timeout specified by the $id param‐
156 eter.
157 $reactor->toggle_timeout($id, $status[, $interval]);
159 Updates the state of a previously registered timeout specifed by
160 the $id parameter. The $status parameter specifies whether the
161 timeout is to be enabled or disabled, while the optional $interval
162 parameter can be used to change the period of the timeout.
163 my $id = $reactor->add_hook($callback[, $status]);
165 Registers a new hook to be fired on each iteration of the event
166 loop. The $callback parameter specifies an instance of the
167 "Net::DBus::Callback" class to invoke. The $status parameter deter‐
168 mines whether the hook is initially enabled, or disabled. The
169 return parameter is a unique id which should be used to later
170 remove, or disable the hook.
171 $reactor->remove_hook($id)
173 Removes the previously registered hook identified by $id.
174 $reactor->toggle_hook($id[, $status])
176 Updates the status of the previously registered hook identified by
177 $id. The $status parameter determines whether the hook is to be
178 enabled or disabled.
179 $reactor->remove_read($fd);
181 $reactor->remove_write($fd);
182 $reactor->remove_exception($fd);
183 Removes a watch on the file handle $fd.
184 $reactor->toggle_read($fd, $status);
186 $reactor->toggle_write($fd, $status);
187 $reactor->toggle_exception($fd, $status);
188 Updates the status of a watch on the file handle $fd. The $status
189 parameter species whether the watch is to be enabled or disabled.
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192 Net::DBus::Callback, Net::DBus::Connection, Net::DBus::Server
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195 Daniel Berrange <dan@berrange.com>
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198 Copyright 2004 by Daniel Berrange
199perl v5.8.8 2008-02-20 Net::DBus::Reactor(3)