1 | =head1 NAME |
1 | =head1 NAME |
2 | |
2 | |
3 | EV - perl interface to libevent, monkey.org/~provos/libevent/ |
3 | EV - perl interface to libev, a high performance full-featured event loop |
4 | |
4 | |
5 | =head1 SYNOPSIS |
5 | =head1 SYNOPSIS |
6 | |
6 | |
7 | use EV; |
7 | use EV; |
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8 | |
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9 | # TIMERS |
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10 | |
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11 | my $w = EV::timer 2, 0, sub { |
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12 | warn "is called after 2s"; |
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13 | }; |
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14 | |
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15 | my $w = EV::timer 2, 2, sub { |
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16 | warn "is called roughly every 2s (repeat = 2)"; |
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17 | }; |
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18 | |
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19 | undef $w; # destroy event watcher again |
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20 | |
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21 | my $w = EV::periodic 0, 60, 0, sub { |
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22 | warn "is called every minute, on the minute, exactly"; |
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23 | }; |
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24 | |
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25 | # IO |
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26 | |
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27 | my $w = EV::io *STDIN, EV::READ, sub { |
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28 | my ($w, $revents) = @_; # all callbacks receive the watcher and event mask |
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29 | warn "stdin is readable, you entered: ", <STDIN>; |
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30 | }; |
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31 | |
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32 | # SIGNALS |
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33 | |
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34 | my $w = EV::signal 'QUIT', sub { |
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35 | warn "sigquit received\n"; |
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36 | }; |
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37 | |
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38 | # CHILD/PID STATUS CHANGES |
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39 | |
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40 | my $w = EV::child 666, sub { |
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41 | my ($w, $revents) = @_; |
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42 | my $status = $w->rstatus; |
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43 | }; |
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44 | |
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45 | # MAINLOOP |
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46 | EV::loop; # loop until EV::unloop is called or all watchers stop |
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47 | EV::loop EV::LOOP_ONESHOT; # block until at least one event could be handled |
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48 | EV::loop EV::LOOP_NONBLOCK; # try to handle same events, but do not block |
8 | |
49 | |
9 | =head1 DESCRIPTION |
50 | =head1 DESCRIPTION |
10 | |
51 | |
11 | This module provides an interface to libevent |
52 | This module provides an interface to libev |
12 | (L<http://monkey.org/~provos/libevent/>). |
53 | (L<http://software.schmorp.de/pkg/libev.html>). |
13 | |
54 | |
14 | =cut |
55 | =cut |
15 | |
56 | |
16 | package EV; |
57 | package EV; |
17 | |
58 | |
18 | use strict; |
59 | use strict; |
19 | |
60 | |
20 | BEGIN { |
61 | BEGIN { |
21 | our $VERSION = '0.01'; |
62 | our $VERSION = '1.2'; |
22 | use XSLoader; |
63 | use XSLoader; |
23 | XSLoader::load "EV", $VERSION; |
64 | XSLoader::load "EV", $VERSION; |
24 | } |
65 | } |
25 | |
66 | |
26 | =head1 FUNCTIONAL INTERFACE |
67 | @EV::Io::ISA = |
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68 | @EV::Timer::ISA = |
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69 | @EV::Periodic::ISA = |
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70 | @EV::Signal::ISA = |
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71 | @EV::Idle::ISA = |
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72 | @EV::Prepare::ISA = |
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73 | @EV::Check::ISA = |
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74 | @EV::Child::ISA = "EV::Watcher"; |
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75 | |
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76 | =head1 BASIC INTERFACE |
27 | |
77 | |
28 | =over 4 |
78 | =over 4 |
29 | |
79 | |
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80 | =item $EV::DIED |
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81 | |
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82 | Must contain a reference to a function that is called when a callback |
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83 | throws an exception (with $@ containing thr error). The default prints an |
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84 | informative message and continues. |
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85 | |
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86 | If this callback throws an exception it will be silently ignored. |
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87 | |
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88 | =item $time = EV::time |
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89 | |
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90 | Returns the current time in (fractional) seconds since the epoch. |
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91 | |
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92 | =item $time = EV::now |
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93 | |
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94 | Returns the time the last event loop iteration has been started. This |
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95 | is the time that (relative) timers are based on, and refering to it is |
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96 | usually faster then calling EV::time. |
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97 | |
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98 | =item $method = EV::method |
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99 | |
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100 | Returns an integer describing the backend used by libev (EV::METHOD_SELECT |
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101 | or EV::METHOD_EPOLL). |
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102 | |
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103 | =item EV::loop [$flags] |
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104 | |
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105 | Begin checking for events and calling callbacks. It returns when a |
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106 | callback calls EV::unloop. |
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107 | |
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108 | The $flags argument can be one of the following: |
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109 | |
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110 | 0 as above |
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111 | EV::LOOP_ONESHOT block at most once (wait, but do not loop) |
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112 | EV::LOOP_NONBLOCK do not block at all (fetch/handle events but do not wait) |
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113 | |
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114 | =item EV::unloop [$how] |
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115 | |
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116 | When called with no arguments or an argument of EV::UNLOOP_ONE, makes the |
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117 | innermost call to EV::loop return. |
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118 | |
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119 | When called with an argument of EV::UNLOOP_ALL, all calls to EV::loop will return as |
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120 | fast as possible. |
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121 | |
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122 | =item EV::once $fh_or_undef, $events, $timeout, $cb->($events) |
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123 | |
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124 | This function rolls together an I/O and a timer watcher for a single |
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125 | one-shot event without the need for managing a watcher object. |
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126 | |
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127 | If C<$fh_or_undef> is a filehandle or file descriptor, then C<$events> |
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128 | must be a bitset containing either C<EV::READ>, C<EV::WRITE> or C<EV::READ |
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129 | | EV::WRITE>, indicating the type of I/O event you want to wait for. If |
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130 | you do not want to wait for some I/O event, specify C<undef> for |
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131 | C<$fh_or_undef> and C<0> for C<$events>). |
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132 | |
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133 | If timeout is C<undef> or negative, then there will be no |
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134 | timeout. Otherwise a EV::timer with this value will be started. |
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135 | |
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136 | When an error occurs or either the timeout or I/O watcher triggers, then |
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137 | the callback will be called with the received event set (in general |
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138 | you can expect it to be a combination of C<EV:ERROR>, C<EV::READ>, |
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139 | C<EV::WRITE> and C<EV::TIMEOUT>). |
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140 | |
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141 | EV::once doesn't return anything: the watchers stay active till either |
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142 | of them triggers, then they will be stopped and freed, and the callback |
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143 | invoked. |
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144 | |
30 | =back |
145 | =back |
31 | |
146 | |
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147 | =head2 WATCHER |
32 | |
148 | |
33 | =head1 OBJECT-ORIENTED INTERFACE |
149 | A watcher is an object that gets created to record your interest in some |
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150 | event. For instance, if you want to wait for STDIN to become readable, you |
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151 | would create an EV::io watcher for that: |
34 | |
152 | |
35 | The object oriented interface lets you configure your own encoding or |
153 | my $watcher = EV::io *STDIN, EV::READ, sub { |
36 | decoding style, within the limits of supported formats. |
154 | my ($watcher, $revents) = @_; |
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155 | warn "yeah, STDIN should not be readable without blocking!\n" |
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156 | }; |
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157 | |
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158 | All watchers can be active (waiting for events) or inactive (paused). Only |
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159 | active watchers will have their callbacks invoked. All callbacks will be |
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160 | called with at least two arguments: the watcher and a bitmask of received |
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161 | events. |
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162 | |
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163 | Each watcher type has its associated bit in revents, so you can use the |
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164 | same callback for multiple watchers. The event mask is named after the |
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165 | type, i..e. EV::child sets EV::CHILD, EV::prepare sets EV::PREPARE, |
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166 | EV::periodic sets EV::PERIODIC and so on, with the exception of IO events |
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167 | (which can set both EV::READ and EV::WRITE bits), and EV::timer (which |
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168 | uses EV::TIMEOUT). |
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169 | |
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170 | In the rare case where one wants to create a watcher but not start it at |
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171 | the same time, each constructor has a variant with a trailing C<_ns> in |
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172 | its name, e.g. EV::io has a non-starting variant EV::io_ns and so on. |
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173 | |
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174 | Please note that a watcher will automatically be stopped when the watcher |
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175 | object is destroyed, so you I<need> to keep the watcher objects returned by |
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176 | the constructors. |
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177 | |
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178 | Also, all methods changing some aspect of a watcher (->set, ->priority, |
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179 | ->fh and so on) automatically stop and start it again if it is active, |
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180 | which means pending events get lost. |
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181 | |
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182 | =head2 WATCHER TYPES |
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183 | |
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184 | Now lets move to the existing watcher types and asociated methods. |
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185 | |
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186 | The following methods are available for all watchers. Then followes a |
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187 | description of each watcher constructor (EV::io, EV::timer, EV::periodic, |
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188 | EV::signal, EV::child, EV::idle, EV::prepare and EV::check), followed by |
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189 | any type-specific methods (if any). |
37 | |
190 | |
38 | =over 4 |
191 | =over 4 |
39 | |
192 | |
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193 | =item $w->start |
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194 | |
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195 | Starts a watcher if it isn't active already. Does nothing to an already |
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196 | active watcher. By default, all watchers start out in the active state |
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197 | (see the description of the C<_ns> variants if you need stopped watchers). |
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198 | |
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199 | =item $w->stop |
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200 | |
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201 | Stop a watcher if it is active. Also clear any pending events (events that |
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202 | have been received but that didn't yet result in a callback invocation), |
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203 | regardless of wether the watcher was active or not. |
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204 | |
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205 | =item $bool = $w->is_active |
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206 | |
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207 | Returns true if the watcher is active, false otherwise. |
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208 | |
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209 | =item $current_data = $w->data |
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210 | |
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211 | =item $old_data = $w->data ($new_data) |
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212 | |
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213 | Queries a freely usable data scalar on the watcher and optionally changes |
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214 | it. This is a way to associate custom data with a watcher: |
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215 | |
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216 | my $w = EV::timer 60, 0, sub { |
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217 | warn $_[0]->data; |
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218 | }; |
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219 | $w->data ("print me!"); |
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220 | |
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221 | =item $current_cb = $w->cb |
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222 | |
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223 | =item $old_cb = $w->cb ($new_cb) |
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224 | |
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225 | Queries the callback on the watcher and optionally changes it. You can do |
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226 | this at any time without the watcher restarting. |
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227 | |
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228 | =item $current_priority = $w->priority |
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229 | |
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230 | =item $old_priority = $w->priority ($new_priority) |
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231 | |
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232 | Queries the priority on the watcher and optionally changes it. Pending |
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233 | watchers with higher priority will be invoked first. The valid range of |
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234 | priorities lies between EV::MAXPRI (default 2) and EV::MINPRI (default |
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235 | -2). If the priority is outside this range it will automatically be |
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236 | normalised to the nearest valid priority. |
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237 | |
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238 | The default priority of any newly-created weatcher is 0. |
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239 | |
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240 | =item $w->trigger ($revents) |
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241 | |
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242 | Call the callback *now* with the given event mask. |
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243 | |
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244 | |
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245 | =item $w = EV::io $fileno_or_fh, $eventmask, $callback |
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246 | |
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247 | =item $w = EV::io_ns $fileno_or_fh, $eventmask, $callback |
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248 | |
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249 | As long as the returned watcher object is alive, call the C<$callback> |
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250 | when the events specified in C<$eventmask>. |
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251 | |
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252 | The $eventmask can be one or more of these constants ORed together: |
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253 | |
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254 | EV::READ wait until read() wouldn't block anymore |
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255 | EV::WRITE wait until write() wouldn't block anymore |
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256 | |
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257 | The C<io_ns> variant doesn't start (activate) the newly created watcher. |
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258 | |
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259 | =item $w->set ($fileno_or_fh, $eventmask) |
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260 | |
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261 | Reconfigures the watcher, see the constructor above for details. Can be |
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262 | called at any time. |
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263 | |
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264 | =item $current_fh = $w->fh |
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265 | |
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266 | =item $old_fh = $w->fh ($new_fh) |
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267 | |
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268 | Returns the previously set filehandle and optionally set a new one. |
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269 | |
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270 | =item $current_eventmask = $w->events |
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271 | |
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272 | =item $old_eventmask = $w->events ($new_eventmask) |
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273 | |
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274 | Returns the previously set event mask and optionally set a new one. |
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275 | |
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276 | |
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277 | =item $w = EV::timer $after, $repeat, $callback |
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278 | |
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279 | =item $w = EV::timer_ns $after, $repeat, $callback |
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280 | |
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281 | Calls the callback after C<$after> seconds. If C<$repeat> is non-zero, |
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282 | the timer will be restarted (with the $repeat value as $after) after the |
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283 | callback returns. |
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284 | |
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285 | This means that the callback would be called roughly after C<$after> |
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286 | seconds, and then every C<$repeat> seconds. The timer does his best not |
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287 | to drift, but it will not invoke the timer more often then once per event |
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288 | loop iteration, and might drift in other cases. If that isn't acceptable, |
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289 | look at EV::periodic, which can provide long-term stable timers. |
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290 | |
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291 | The timer is based on a monotonic clock, that is, if somebody is sitting |
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292 | in front of the machine while the timer is running and changes the system |
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293 | clock, the timer will nevertheless run (roughly) the same time. |
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294 | |
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295 | The C<timer_ns> variant doesn't start (activate) the newly created watcher. |
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296 | |
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297 | =item $w->set ($after, $repeat) |
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298 | |
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299 | Reconfigures the watcher, see the constructor above for details. Can be at |
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300 | any time. |
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301 | |
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302 | =item $w->again |
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303 | |
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304 | Similar to the C<start> method, but has special semantics for repeating timers: |
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305 | |
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306 | If the timer is active and non-repeating, it will be stopped. |
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307 | |
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308 | If the timer is active and repeating, reset the timeout to occur |
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309 | C<$repeat> seconds after now. |
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310 | |
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311 | If the timer is inactive and repeating, start it using the repeat value. |
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312 | |
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313 | Otherwise do nothing. |
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314 | |
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315 | This behaviour is useful when you have a timeout for some IO |
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316 | operation. You create a timer object with the same value for C<$after> and |
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317 | C<$repeat>, and then, in the read/write watcher, run the C<again> method |
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318 | on the timeout. |
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319 | |
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320 | |
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321 | =item $w = EV::periodic $at, $interval, $reschedule_cb, $callback |
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322 | |
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323 | =item $w = EV::periodic_ns $at, $interval, $reschedule_cb, $callback |
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324 | |
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325 | Similar to EV::timer, but is not based on relative timeouts but on |
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326 | absolute times. Apart from creating "simple" timers that trigger "at" the |
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327 | specified time, it can also be used for non-drifting absolute timers and |
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328 | more complex, cron-like, setups that are not adversely affected by time |
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329 | jumps (i.e. when the system clock is changed by explicit date -s or other |
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330 | means such as ntpd). It is also the most complex watcher type in EV. |
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331 | |
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332 | It has three distinct "modes": |
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333 | |
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334 | =over 4 |
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335 | |
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336 | =item * absolute timer ($interval = $reschedule_cb = 0) |
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337 | |
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338 | This time simply fires at the wallclock time C<$at> and doesn't repeat. It |
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339 | will not adjust when a time jump occurs, that is, if it is to be run |
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340 | at January 1st 2011 then it will run when the system time reaches or |
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341 | surpasses this time. |
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342 | |
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343 | =item * non-repeating interval timer ($interval > 0, $reschedule_cb = 0) |
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344 | |
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345 | In this mode the watcher will always be scheduled to time out at the |
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346 | next C<$at + N * $interval> time (for some integer N) and then repeat, |
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347 | regardless of any time jumps. |
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348 | |
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349 | This can be used to create timers that do not drift with respect to system |
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350 | time: |
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351 | |
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352 | my $hourly = EV::periodic 0, 3600, 0, sub { print "once/hour\n" }; |
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353 | |
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354 | That doesn't mean there will always be 3600 seconds in between triggers, |
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355 | but only that the the clalback will be called when the system time shows a |
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356 | full hour (UTC). |
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357 | |
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358 | Another way to think about it (for the mathematically inclined) is that |
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359 | EV::periodic will try to run the callback in this mode at the next |
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360 | possible time where C<$time = $at (mod $interval)>, regardless of any time |
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361 | jumps. |
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362 | |
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363 | =item * manual reschedule mode ($reschedule_cb = coderef) |
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364 | |
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365 | In this mode $interval and $at are both being ignored. Instead, each |
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366 | time the periodic watcher gets scheduled, the reschedule callback |
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367 | ($reschedule_cb) will be called with the watcher as first, and the current |
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368 | time as second argument. |
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369 | |
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370 | I<This callback MUST NOT stop or destroy this or any other periodic |
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371 | watcher, ever>. If you need to stop it, return 1e30 and stop it |
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372 | afterwards. |
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373 | |
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374 | It must return the next time to trigger, based on the passed time value |
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375 | (that is, the lowest time value larger than to the second argument). It |
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376 | will usually be called just before the callback will be triggered, but |
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377 | might be called at other times, too. |
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378 | |
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379 | This can be used to create very complex timers, such as a timer that |
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380 | triggers on each midnight, local time (actually 24 hours after the last |
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381 | midnight, to keep the example simple. If you know a way to do it correctly |
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382 | in about the same space (without requiring elaborate modules), drop me a |
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383 | note :): |
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384 | |
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385 | my $daily = EV::periodic 0, 0, sub { |
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386 | my ($w, $now) = @_; |
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387 | |
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388 | use Time::Local (); |
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389 | my (undef, undef, undef, $d, $m, $y) = localtime $now; |
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390 | 86400 + Time::Local::timelocal 0, 0, 0, $d, $m, $y |
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391 | }, sub { |
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392 | print "it's midnight or likely shortly after, now\n"; |
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393 | }; |
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394 | |
40 | =back |
395 | =back |
41 | |
396 | |
42 | =head1 BUGS |
397 | The C<periodic_ns> variant doesn't start (activate) the newly created watcher. |
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398 | |
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399 | =item $w->set ($at, $interval, $reschedule_cb) |
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400 | |
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401 | Reconfigures the watcher, see the constructor above for details. Can be at |
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402 | any time. |
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403 | |
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404 | =item $w->again |
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405 | |
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406 | Simply stops and starts the watcher again. |
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407 | |
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408 | |
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409 | =item $w = EV::signal $signal, $callback |
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410 | |
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411 | =item $w = EV::signal_ns $signal, $callback |
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412 | |
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413 | Call the callback when $signal is received (the signal can be specified |
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414 | by number or by name, just as with kill or %SIG). |
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415 | |
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416 | EV will grab the signal for the process (the kernel only allows one |
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417 | component to receive a signal at a time) when you start a signal watcher, |
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418 | and removes it again when you stop it. Perl does the same when you |
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419 | add/remove callbacks to %SIG, so watch out. |
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420 | |
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421 | You can have as many signal watchers per signal as you want. |
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422 | |
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423 | The C<signal_ns> variant doesn't start (activate) the newly created watcher. |
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424 | |
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425 | =item $w->set ($signal) |
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426 | |
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427 | Reconfigures the watcher, see the constructor above for details. Can be at |
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428 | any time. |
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429 | |
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430 | =item $current_signum = $w->signal |
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431 | |
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432 | =item $old_signum = $w->signal ($new_signal) |
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433 | |
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434 | Returns the previously set signal (always as a number not name) and |
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435 | optionally set a new one. |
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436 | |
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437 | |
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438 | =item $w = EV::child $pid, $callback |
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439 | |
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440 | =item $w = EV::child_ns $pid, $callback |
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441 | |
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442 | Call the callback when a status change for pid C<$pid> (or any pid |
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443 | if C<$pid> is 0) has been received. More precisely: when the process |
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444 | receives a SIGCHLD, EV will fetch the outstanding exit/wait status for all |
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445 | changed/zombie children and call the callback. |
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446 | |
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447 | You can access both status and pid by using the C<rstatus> and C<rpid> |
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448 | methods on the watcher object. |
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449 | |
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450 | You can have as many pid watchers per pid as you want. |
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451 | |
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452 | The C<child_ns> variant doesn't start (activate) the newly created watcher. |
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453 | |
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454 | =item $w->set ($pid) |
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455 | |
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456 | Reconfigures the watcher, see the constructor above for details. Can be at |
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457 | any time. |
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458 | |
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459 | =item $current_pid = $w->pid |
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460 | |
|
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461 | =item $old_pid = $w->pid ($new_pid) |
|
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462 | |
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463 | Returns the previously set process id and optionally set a new one. |
|
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464 | |
|
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465 | =item $exit_status = $w->rstatus |
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466 | |
|
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467 | Return the exit/wait status (as returned by waitpid, see the waitpid entry |
|
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468 | in perlfunc). |
|
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469 | |
|
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470 | =item $pid = $w->rpid |
|
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471 | |
|
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472 | Return the pid of the awaited child (useful when you have installed a |
|
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473 | watcher for all pids). |
|
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474 | |
|
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475 | |
|
|
476 | =item $w = EV::idle $callback |
|
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477 | |
|
|
478 | =item $w = EV::idle_ns $callback |
|
|
479 | |
|
|
480 | Call the callback when there are no pending io, timer/periodic, signal or |
|
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481 | child events, i.e. when the process is idle. |
|
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482 | |
|
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483 | The process will not block as long as any idle watchers are active, and |
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484 | they will be called repeatedly until stopped. |
|
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485 | |
|
|
486 | The C<idle_ns> variant doesn't start (activate) the newly created watcher. |
|
|
487 | |
|
|
488 | |
|
|
489 | =item $w = EV::prepare $callback |
|
|
490 | |
|
|
491 | =item $w = EV::prepare_ns $callback |
|
|
492 | |
|
|
493 | Call the callback just before the process would block. You can still |
|
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494 | create/modify any watchers at this point. |
|
|
495 | |
|
|
496 | See the EV::check watcher, below, for explanations and an example. |
|
|
497 | |
|
|
498 | The C<prepare_ns> variant doesn't start (activate) the newly created watcher. |
|
|
499 | |
|
|
500 | |
|
|
501 | =item $w = EV::check $callback |
|
|
502 | |
|
|
503 | =item $w = EV::check_ns $callback |
|
|
504 | |
|
|
505 | Call the callback just after the process wakes up again (after it has |
|
|
506 | gathered events), but before any other callbacks have been invoked. |
|
|
507 | |
|
|
508 | This is used to integrate other event-based software into the EV |
|
|
509 | mainloop: You register a prepare callback and in there, you create io and |
|
|
510 | timer watchers as required by the other software. Here is a real-world |
|
|
511 | example of integrating Net::SNMP (with some details left out): |
|
|
512 | |
|
|
513 | our @snmp_watcher; |
|
|
514 | |
|
|
515 | our $snmp_prepare = EV::prepare sub { |
|
|
516 | # do nothing unless active |
|
|
517 | $dispatcher->{_event_queue_h} |
|
|
518 | or return; |
|
|
519 | |
|
|
520 | # make the dispatcher handle any outstanding stuff |
|
|
521 | ... not shown |
|
|
522 | |
|
|
523 | # create an IO watcher for each and every socket |
|
|
524 | @snmp_watcher = ( |
|
|
525 | (map { EV::io $_, EV::READ, sub { } } |
|
|
526 | keys %{ $dispatcher->{_descriptors} }), |
|
|
527 | |
|
|
528 | EV::timer +($event->[Net::SNMP::Dispatcher::_ACTIVE] |
|
|
529 | ? $event->[Net::SNMP::Dispatcher::_TIME] - EV::now : 0), |
|
|
530 | 0, sub { }, |
|
|
531 | ); |
|
|
532 | }; |
|
|
533 | |
|
|
534 | The callbacks are irrelevant (and are not even being called), the |
|
|
535 | only purpose of those watchers is to wake up the process as soon as |
|
|
536 | one of those events occurs (socket readable, or timer timed out). The |
|
|
537 | corresponding EV::check watcher will then clean up: |
|
|
538 | |
|
|
539 | our $snmp_check = EV::check sub { |
|
|
540 | # destroy all watchers |
|
|
541 | @snmp_watcher = (); |
|
|
542 | |
|
|
543 | # make the dispatcher handle any new stuff |
|
|
544 | ... not shown |
|
|
545 | }; |
|
|
546 | |
|
|
547 | The callbacks of the created watchers will not be called as the watchers |
|
|
548 | are destroyed before this cna happen (remember EV::check gets called |
|
|
549 | first). |
|
|
550 | |
|
|
551 | The C<check_ns> variant doesn't start (activate) the newly created watcher. |
|
|
552 | |
|
|
553 | =back |
|
|
554 | |
|
|
555 | =head1 THREADS |
|
|
556 | |
|
|
557 | Threads are not supported by this module in any way. Perl pseudo-threads |
|
|
558 | is evil stuff and must die. As soon as Perl gains real threads I will work |
|
|
559 | on thread support for it. |
|
|
560 | |
|
|
561 | =head1 FORK |
|
|
562 | |
|
|
563 | Most of the "improved" event delivering mechanisms of modern operating |
|
|
564 | systems have quite a few problems with fork(2) (to put it bluntly: it is |
|
|
565 | not supported and usually destructive). Libev makes it possible to work |
|
|
566 | around this by having a function that recreates the kernel state after |
|
|
567 | fork in the child. |
|
|
568 | |
|
|
569 | On non-win32 platforms, this module requires the pthread_atfork |
|
|
570 | functionality to do this automatically for you. This function is quite |
|
|
571 | buggy on most BSDs, though, so YMMV. The overhead for this is quite |
|
|
572 | negligible, because everything the function currently does is set a flag |
|
|
573 | that is checked only when the event loop gets used the next time, so when |
|
|
574 | you do fork but not use EV, the overhead is minimal. |
|
|
575 | |
|
|
576 | On win32, there is no notion of fork so all this doesn't apply, of course. |
43 | |
577 | |
44 | =cut |
578 | =cut |
45 | |
579 | |
46 | our $NPRI = 4; |
580 | our $DIED = sub { |
47 | our $BASE = init; |
581 | warn "EV: error in callback (ignoring): $@"; |
48 | priority_init $NPRI; |
582 | }; |
|
|
583 | |
|
|
584 | default_loop |
|
|
585 | or die 'EV: cannot initialise libev backend. bad $ENV{LIBEV_METHODS}?'; |
49 | |
586 | |
50 | 1; |
587 | 1; |
|
|
588 | |
|
|
589 | =head1 SEE ALSO |
|
|
590 | |
|
|
591 | L<EV::DNS>. |
51 | |
592 | |
52 | =head1 AUTHOR |
593 | =head1 AUTHOR |
53 | |
594 | |
54 | Marc Lehmann <schmorp@schmorp.de> |
595 | Marc Lehmann <schmorp@schmorp.de> |
55 | http://home.schmorp.de/ |
596 | http://home.schmorp.de/ |