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4<head> 4<head>
5 <title>libev</title> 5 <title>libev</title>
6 <meta name="description" content="Pod documentation for libev" /> 6 <meta name="description" content="Pod documentation for libev" />
7 <meta name="inputfile" content="&lt;standard input&gt;" /> 7 <meta name="inputfile" content="&lt;standard input&gt;" />
8 <meta name="outputfile" content="&lt;standard output&gt;" /> 8 <meta name="outputfile" content="&lt;standard output&gt;" />
9 <meta name="created" content="Sat Nov 24 08:13:46 2007" /> 9 <meta name="created" content="Mon Nov 26 11:20:35 2007" />
10 <meta name="generator" content="Pod::Xhtml 1.57" /> 10 <meta name="generator" content="Pod::Xhtml 1.57" />
11<link rel="stylesheet" href="http://res.tst.eu/pod.css"/></head> 11<link rel="stylesheet" href="http://res.tst.eu/pod.css"/></head>
12<body> 12<body>
13<div class="pod"> 13<div class="pod">
14<!-- INDEX START --> 14<!-- INDEX START -->
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21<li><a href="#CONVENTIONS">CONVENTIONS</a></li> 21<li><a href="#CONVENTIONS">CONVENTIONS</a></li>
22<li><a href="#TIME_REPRESENTATION">TIME REPRESENTATION</a></li> 22<li><a href="#TIME_REPRESENTATION">TIME REPRESENTATION</a></li>
23<li><a href="#GLOBAL_FUNCTIONS">GLOBAL FUNCTIONS</a></li> 23<li><a href="#GLOBAL_FUNCTIONS">GLOBAL FUNCTIONS</a></li>
24<li><a href="#FUNCTIONS_CONTROLLING_THE_EVENT_LOOP">FUNCTIONS CONTROLLING THE EVENT LOOP</a></li> 24<li><a href="#FUNCTIONS_CONTROLLING_THE_EVENT_LOOP">FUNCTIONS CONTROLLING THE EVENT LOOP</a></li>
25<li><a href="#ANATOMY_OF_A_WATCHER">ANATOMY OF A WATCHER</a> 25<li><a href="#ANATOMY_OF_A_WATCHER">ANATOMY OF A WATCHER</a>
26<ul><li><a href="#SUMMARY_OF_GENERIC_WATCHER_FUNCTIONS">SUMMARY OF GENERIC WATCHER FUNCTIONS</a></li> 26<ul><li><a href="#GENERIC_WATCHER_FUNCTIONS">GENERIC WATCHER FUNCTIONS</a></li>
27<li><a href="#ASSOCIATING_CUSTOM_DATA_WITH_A_WATCH">ASSOCIATING CUSTOM DATA WITH A WATCHER</a></li> 27<li><a href="#ASSOCIATING_CUSTOM_DATA_WITH_A_WATCH">ASSOCIATING CUSTOM DATA WITH A WATCHER</a></li>
28</ul> 28</ul>
29</li> 29</li>
30<li><a href="#WATCHER_TYPES">WATCHER TYPES</a> 30<li><a href="#WATCHER_TYPES">WATCHER TYPES</a>
31<ul><li><a href="#code_ev_io_code_is_this_file_descrip"><code>ev_io</code> - is this file descriptor readable or writable</a></li> 31<ul><li><a href="#code_ev_io_code_is_this_file_descrip"><code>ev_io</code> - is this file descriptor readable or writable?</a></li>
32<li><a href="#code_ev_timer_code_relative_and_opti"><code>ev_timer</code> - relative and optionally recurring timeouts</a></li> 32<li><a href="#code_ev_timer_code_relative_and_opti"><code>ev_timer</code> - relative and optionally repeating timeouts</a></li>
33<li><a href="#code_ev_periodic_code_to_cron_or_not"><code>ev_periodic</code> - to cron or not to cron</a></li> 33<li><a href="#code_ev_periodic_code_to_cron_or_not"><code>ev_periodic</code> - to cron or not to cron?</a></li>
34<li><a href="#code_ev_signal_code_signal_me_when_a"><code>ev_signal</code> - signal me when a signal gets signalled</a></li> 34<li><a href="#code_ev_signal_code_signal_me_when_a"><code>ev_signal</code> - signal me when a signal gets signalled!</a></li>
35<li><a href="#code_ev_child_code_wait_for_pid_stat"><code>ev_child</code> - wait for pid status changes</a></li> 35<li><a href="#code_ev_child_code_watch_out_for_pro"><code>ev_child</code> - watch out for process status changes</a></li>
36<li><a href="#code_ev_idle_code_when_you_ve_got_no"><code>ev_idle</code> - when you've got nothing better to do</a></li> 36<li><a href="#code_ev_idle_code_when_you_ve_got_no"><code>ev_idle</code> - when you've got nothing better to do...</a></li>
37<li><a href="#code_ev_prepare_code_and_code_ev_che"><code>ev_prepare</code> and <code>ev_check</code> - customise your event loop</a></li> 37<li><a href="#code_ev_prepare_code_and_code_ev_che"><code>ev_prepare</code> and <code>ev_check</code> - customise your event loop!</a></li>
38<li><a href="#code_ev_embed_code_when_one_backend_"><code>ev_embed</code> - when one backend isn't enough</a></li> 38<li><a href="#code_ev_embed_code_when_one_backend_"><code>ev_embed</code> - when one backend isn't enough...</a></li>
39</ul> 39</ul>
40</li> 40</li>
41<li><a href="#OTHER_FUNCTIONS">OTHER FUNCTIONS</a></li> 41<li><a href="#OTHER_FUNCTIONS">OTHER FUNCTIONS</a></li>
42<li><a href="#LIBEVENT_EMULATION">LIBEVENT EMULATION</a></li> 42<li><a href="#LIBEVENT_EMULATION">LIBEVENT EMULATION</a></li>
43<li><a href="#C_SUPPORT">C++ SUPPORT</a></li> 43<li><a href="#C_SUPPORT">C++ SUPPORT</a></li>
44<li><a href="#EMBEDDING">EMBEDDING</a>
45<ul><li><a href="#FILESETS">FILESETS</a>
46<ul><li><a href="#CORE_EVENT_LOOP">CORE EVENT LOOP</a></li>
47<li><a href="#LIBEVENT_COMPATIBILITY_API">LIBEVENT COMPATIBILITY API</a></li>
48<li><a href="#AUTOCONF_SUPPORT">AUTOCONF SUPPORT</a></li>
49</ul>
50</li>
51<li><a href="#PREPROCESSOR_SYMBOLS_MACROS">PREPROCESSOR SYMBOLS/MACROS</a></li>
52<li><a href="#EXAMPLES">EXAMPLES</a></li>
53</ul>
54</li>
55<li><a href="#COMPLEXITIES">COMPLEXITIES</a></li>
44<li><a href="#AUTHOR">AUTHOR</a> 56<li><a href="#AUTHOR">AUTHOR</a>
45</li> 57</li>
46</ul><hr /> 58</ul><hr />
47<!-- INDEX END --> 59<!-- INDEX END -->
48 60
… …
364</pre> 376</pre>
365 </dd> 377 </dd>
366 <dt>ev_default_destroy ()</dt> 378 <dt>ev_default_destroy ()</dt>
367 <dd> 379 <dd>
368 <p>Destroys the default loop again (frees all memory and kernel state 380 <p>Destroys the default loop again (frees all memory and kernel state
369etc.). This stops all registered event watchers (by not touching them in 381etc.). None of the active event watchers will be stopped in the normal
370any way whatsoever, although you cannot rely on this :).</p> 382sense, so e.g. <code>ev_is_active</code> might still return true. It is your
383responsibility to either stop all watchers cleanly yoursef <i>before</i>
384calling this function, or cope with the fact afterwards (which is usually
385the easiest thing, youc na just ignore the watchers and/or <code>free ()</code> them
386for example).</p>
371 </dd> 387 </dd>
372 <dt>ev_loop_destroy (loop)</dt> 388 <dt>ev_loop_destroy (loop)</dt>
373 <dd> 389 <dd>
374 <p>Like <code>ev_default_destroy</code>, but destroys an event loop created by an 390 <p>Like <code>ev_default_destroy</code>, but destroys an event loop created by an
375earlier call to <code>ev_loop_new</code>.</p> 391earlier call to <code>ev_loop_new</code>.</p>
… …
498 514
499</pre> 515</pre>
500 </dd> 516 </dd>
501</dl> 517</dl>
502 518
519
520
521
522
503</div> 523</div>
504<h1 id="ANATOMY_OF_A_WATCHER">ANATOMY OF A WATCHER</h1><p><a href="#TOP" class="toplink">Top</a></p> 524<h1 id="ANATOMY_OF_A_WATCHER">ANATOMY OF A WATCHER</h1><p><a href="#TOP" class="toplink">Top</a></p>
505<div id="ANATOMY_OF_A_WATCHER_CONTENT"> 525<div id="ANATOMY_OF_A_WATCHER_CONTENT">
506<p>A watcher is a structure that you create and register to record your 526<p>A watcher is a structure that you create and register to record your
507interest in some event. For instance, if you want to wait for STDIN to 527interest in some event. For instance, if you want to wait for STDIN to
… …
597programs, though, so beware.</p> 617programs, though, so beware.</p>
598 </dd> 618 </dd>
599</dl> 619</dl>
600 620
601</div> 621</div>
602<h2 id="SUMMARY_OF_GENERIC_WATCHER_FUNCTIONS">SUMMARY OF GENERIC WATCHER FUNCTIONS</h2> 622<h2 id="GENERIC_WATCHER_FUNCTIONS">GENERIC WATCHER FUNCTIONS</h2>
603<div id="SUMMARY_OF_GENERIC_WATCHER_FUNCTIONS-2"> 623<div id="GENERIC_WATCHER_FUNCTIONS_CONTENT">
604<p>In the following description, <code>TYPE</code> stands for the watcher type, 624<p>In the following description, <code>TYPE</code> stands for the watcher type,
605e.g. <code>timer</code> for <code>ev_timer</code> watchers and <code>io</code> for <code>ev_io</code> watchers.</p> 625e.g. <code>timer</code> for <code>ev_timer</code> watchers and <code>io</code> for <code>ev_io</code> watchers.</p>
606<dl> 626<dl>
607 <dt><code>ev_init</code> (ev_TYPE *watcher, callback)</dt> 627 <dt><code>ev_init</code> (ev_TYPE *watcher, callback)</dt>
608 <dd> 628 <dd>
… …
612the type-specific <code>ev_TYPE_set</code> macro afterwards to initialise the 632the type-specific <code>ev_TYPE_set</code> macro afterwards to initialise the
613type-specific parts. For each type there is also a <code>ev_TYPE_init</code> macro 633type-specific parts. For each type there is also a <code>ev_TYPE_init</code> macro
614which rolls both calls into one.</p> 634which rolls both calls into one.</p>
615 <p>You can reinitialise a watcher at any time as long as it has been stopped 635 <p>You can reinitialise a watcher at any time as long as it has been stopped
616(or never started) and there are no pending events outstanding.</p> 636(or never started) and there are no pending events outstanding.</p>
617 <p>The callbakc is always of type <code>void (*)(ev_loop *loop, ev_TYPE *watcher, 637 <p>The callback is always of type <code>void (*)(ev_loop *loop, ev_TYPE *watcher,
618int revents)</code>.</p> 638int revents)</code>.</p>
619 </dd> 639 </dd>
620 <dt><code>ev_TYPE_set</code> (ev_TYPE *, [args])</dt> 640 <dt><code>ev_TYPE_set</code> (ev_TYPE *, [args])</dt>
621 <dd> 641 <dd>
622 <p>This macro initialises the type-specific parts of a watcher. You need to 642 <p>This macro initialises the type-specific parts of a watcher. You need to
… …
719 739
720 740
721 741
722 742
723</div> 743</div>
724<h2 id="code_ev_io_code_is_this_file_descrip"><code>ev_io</code> - is this file descriptor readable or writable</h2> 744<h2 id="code_ev_io_code_is_this_file_descrip"><code>ev_io</code> - is this file descriptor readable or writable?</h2>
725<div id="code_ev_io_code_is_this_file_descrip-2"> 745<div id="code_ev_io_code_is_this_file_descrip-2">
726<p>I/O watchers check whether a file descriptor is readable or writable 746<p>I/O watchers check whether a file descriptor is readable or writable
727in each iteration of the event loop (This behaviour is called 747in each iteration of the event loop, or, more precisely, when reading
728level-triggering because you keep receiving events as long as the 748would not block the process and writing would at least be able to write
729condition persists. Remember you can stop the watcher if you don't want to 749some data. This behaviour is called level-triggering because you keep
730act on the event and neither want to receive future events).</p> 750receiving events as long as the condition persists. Remember you can stop
751the watcher if you don't want to act on the event and neither want to
752receive future events.</p>
731<p>In general you can register as many read and/or write event watchers per 753<p>In general you can register as many read and/or write event watchers per
732fd as you want (as long as you don't confuse yourself). Setting all file 754fd as you want (as long as you don't confuse yourself). Setting all file
733descriptors to non-blocking mode is also usually a good idea (but not 755descriptors to non-blocking mode is also usually a good idea (but not
734required if you know what you are doing).</p> 756required if you know what you are doing).</p>
735<p>You have to be careful with dup'ed file descriptors, though. Some backends 757<p>You have to be careful with dup'ed file descriptors, though. Some backends
736(the linux epoll backend is a notable example) cannot handle dup'ed file 758(the linux epoll backend is a notable example) cannot handle dup'ed file
737descriptors correctly if you register interest in two or more fds pointing 759descriptors correctly if you register interest in two or more fds pointing
738to the same underlying file/socket etc. description (that is, they share 760to the same underlying file/socket/etc. description (that is, they share
739the same underlying &quot;file open&quot;).</p> 761the same underlying &quot;file open&quot;).</p>
740<p>If you must do this, then force the use of a known-to-be-good backend 762<p>If you must do this, then force the use of a known-to-be-good backend
741(at the time of this writing, this includes only <code>EVBACKEND_SELECT</code> and 763(at the time of this writing, this includes only <code>EVBACKEND_SELECT</code> and
742<code>EVBACKEND_POLL</code>).</p> 764<code>EVBACKEND_POLL</code>).</p>
765<p>Another thing you have to watch out for is that it is quite easy to
766receive &quot;spurious&quot; readyness notifications, that is your callback might
767be called with <code>EV_READ</code> but a subsequent <code>read</code>(2) will actually block
768because there is no data. Not only are some backends known to create a
769lot of those (for example solaris ports), it is very easy to get into
770this situation even with a relatively standard program structure. Thus
771it is best to always use non-blocking I/O: An extra <code>read</code>(2) returning
772<code>EAGAIN</code> is far preferable to a program hanging until some data arrives.</p>
773<p>If you cannot run the fd in non-blocking mode (for example you should not
774play around with an Xlib connection), then you have to seperately re-test
775wether a file descriptor is really ready with a known-to-be good interface
776such as poll (fortunately in our Xlib example, Xlib already does this on
777its own, so its quite safe to use).</p>
743<dl> 778<dl>
744 <dt>ev_io_init (ev_io *, callback, int fd, int events)</dt> 779 <dt>ev_io_init (ev_io *, callback, int fd, int events)</dt>
745 <dt>ev_io_set (ev_io *, int fd, int events)</dt> 780 <dt>ev_io_set (ev_io *, int fd, int events)</dt>
746 <dd> 781 <dd>
747 <p>Configures an <code>ev_io</code> watcher. The fd is the file descriptor to rceeive 782 <p>Configures an <code>ev_io</code> watcher. The <code>fd</code> is the file descriptor to
748events for and events is either <code>EV_READ</code>, <code>EV_WRITE</code> or <code>EV_READ | 783rceeive events for and events is either <code>EV_READ</code>, <code>EV_WRITE</code> or
749EV_WRITE</code> to receive the given events.</p> 784<code>EV_READ | EV_WRITE</code> to receive the given events.</p>
750 <p>Please note that most of the more scalable backend mechanisms (for example
751epoll and solaris ports) can result in spurious readyness notifications
752for file descriptors, so you practically need to use non-blocking I/O (and
753treat callback invocation as hint only), or retest separately with a safe
754interface before doing I/O (XLib can do this), or force the use of either
755<code>EVBACKEND_SELECT</code> or <code>EVBACKEND_POLL</code>, which don't suffer from this
756problem. Also note that it is quite easy to have your callback invoked
757when the readyness condition is no longer valid even when employing
758typical ways of handling events, so its a good idea to use non-blocking
759I/O unconditionally.</p>
760 </dd> 785 </dd>
761</dl> 786</dl>
762<p>Example: call <code>stdin_readable_cb</code> when STDIN_FILENO has become, well 787<p>Example: call <code>stdin_readable_cb</code> when STDIN_FILENO has become, well
763readable, but only once. Since it is likely line-buffered, you could 788readable, but only once. Since it is likely line-buffered, you could
764attempt to read a whole line in the callback:</p> 789attempt to read a whole line in the callback:</p>
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780 805
781 806
782</pre> 807</pre>
783 808
784</div> 809</div>
785<h2 id="code_ev_timer_code_relative_and_opti"><code>ev_timer</code> - relative and optionally recurring timeouts</h2> 810<h2 id="code_ev_timer_code_relative_and_opti"><code>ev_timer</code> - relative and optionally repeating timeouts</h2>
786<div id="code_ev_timer_code_relative_and_opti-2"> 811<div id="code_ev_timer_code_relative_and_opti-2">
787<p>Timer watchers are simple relative timers that generate an event after a 812<p>Timer watchers are simple relative timers that generate an event after a
788given time, and optionally repeating in regular intervals after that.</p> 813given time, and optionally repeating in regular intervals after that.</p>
789<p>The timers are based on real time, that is, if you register an event that 814<p>The timers are based on real time, that is, if you register an event that
790times out after an hour and you reset your system clock to last years 815times out after an hour and you reset your system clock to last years
… …
866 891
867 892
868</pre> 893</pre>
869 894
870</div> 895</div>
871<h2 id="code_ev_periodic_code_to_cron_or_not"><code>ev_periodic</code> - to cron or not to cron</h2> 896<h2 id="code_ev_periodic_code_to_cron_or_not"><code>ev_periodic</code> - to cron or not to cron?</h2>
872<div id="code_ev_periodic_code_to_cron_or_not-2"> 897<div id="code_ev_periodic_code_to_cron_or_not-2">
873<p>Periodic watchers are also timers of a kind, but they are very versatile 898<p>Periodic watchers are also timers of a kind, but they are very versatile
874(and unfortunately a bit complex).</p> 899(and unfortunately a bit complex).</p>
875<p>Unlike <code>ev_timer</code>'s, they are not based on real time (or relative time) 900<p>Unlike <code>ev_timer</code>'s, they are not based on real time (or relative time)
876but on wallclock time (absolute time). You can tell a periodic watcher 901but on wallclock time (absolute time). You can tell a periodic watcher
877to trigger &quot;at&quot; some specific point in time. For example, if you tell a 902to trigger &quot;at&quot; some specific point in time. For example, if you tell a
878periodic watcher to trigger in 10 seconds (by specifiying e.g. c&lt;ev_now () 903periodic watcher to trigger in 10 seconds (by specifiying e.g. <code>ev_now ()
879+ 10.&gt;) and then reset your system clock to the last year, then it will 904+ 10.</code>) and then reset your system clock to the last year, then it will
880take a year to trigger the event (unlike an <code>ev_timer</code>, which would trigger 905take a year to trigger the event (unlike an <code>ev_timer</code>, which would trigger
881roughly 10 seconds later and of course not if you reset your system time 906roughly 10 seconds later and of course not if you reset your system time
882again).</p> 907again).</p>
883<p>They can also be used to implement vastly more complex timers, such as 908<p>They can also be used to implement vastly more complex timers, such as
884triggering an event on eahc midnight, local time.</p> 909triggering an event on eahc midnight, local time.</p>
… …
995 1020
996 1021
997</pre> 1022</pre>
998 1023
999</div> 1024</div>
1000<h2 id="code_ev_signal_code_signal_me_when_a"><code>ev_signal</code> - signal me when a signal gets signalled</h2> 1025<h2 id="code_ev_signal_code_signal_me_when_a"><code>ev_signal</code> - signal me when a signal gets signalled!</h2>
1001<div id="code_ev_signal_code_signal_me_when_a-2"> 1026<div id="code_ev_signal_code_signal_me_when_a-2">
1002<p>Signal watchers will trigger an event when the process receives a specific 1027<p>Signal watchers will trigger an event when the process receives a specific
1003signal one or more times. Even though signals are very asynchronous, libev 1028signal one or more times. Even though signals are very asynchronous, libev
1004will try it's best to deliver signals synchronously, i.e. as part of the 1029will try it's best to deliver signals synchronously, i.e. as part of the
1005normal event processing, like any other event.</p> 1030normal event processing, like any other event.</p>
… …
1021 1046
1022 1047
1023 1048
1024 1049
1025</div> 1050</div>
1026<h2 id="code_ev_child_code_wait_for_pid_stat"><code>ev_child</code> - wait for pid status changes</h2> 1051<h2 id="code_ev_child_code_watch_out_for_pro"><code>ev_child</code> - watch out for process status changes</h2>
1027<div id="code_ev_child_code_wait_for_pid_stat-2"> 1052<div id="code_ev_child_code_watch_out_for_pro-2">
1028<p>Child watchers trigger when your process receives a SIGCHLD in response to 1053<p>Child watchers trigger when your process receives a SIGCHLD in response to
1029some child status changes (most typically when a child of yours dies).</p> 1054some child status changes (most typically when a child of yours dies).</p>
1030<dl> 1055<dl>
1031 <dt>ev_child_init (ev_child *, callback, int pid)</dt> 1056 <dt>ev_child_init (ev_child *, callback, int pid)</dt>
1032 <dt>ev_child_set (ev_child *, int pid)</dt> 1057 <dt>ev_child_set (ev_child *, int pid)</dt>
… …
1054 1079
1055 1080
1056</pre> 1081</pre>
1057 1082
1058</div> 1083</div>
1059<h2 id="code_ev_idle_code_when_you_ve_got_no"><code>ev_idle</code> - when you've got nothing better to do</h2> 1084<h2 id="code_ev_idle_code_when_you_ve_got_no"><code>ev_idle</code> - when you've got nothing better to do...</h2>
1060<div id="code_ev_idle_code_when_you_ve_got_no-2"> 1085<div id="code_ev_idle_code_when_you_ve_got_no-2">
1061<p>Idle watchers trigger events when there are no other events are pending 1086<p>Idle watchers trigger events when there are no other events are pending
1062(prepare, check and other idle watchers do not count). That is, as long 1087(prepare, check and other idle watchers do not count). That is, as long
1063as your process is busy handling sockets or timeouts (or even signals, 1088as your process is busy handling sockets or timeouts (or even signals,
1064imagine) it will not be triggered. But when your process is idle all idle 1089imagine) it will not be triggered. But when your process is idle all idle
… …
1097 1122
1098 1123
1099</pre> 1124</pre>
1100 1125
1101</div> 1126</div>
1102<h2 id="code_ev_prepare_code_and_code_ev_che"><code>ev_prepare</code> and <code>ev_check</code> - customise your event loop</h2> 1127<h2 id="code_ev_prepare_code_and_code_ev_che"><code>ev_prepare</code> and <code>ev_check</code> - customise your event loop!</h2>
1103<div id="code_ev_prepare_code_and_code_ev_che-2"> 1128<div id="code_ev_prepare_code_and_code_ev_che-2">
1104<p>Prepare and check watchers are usually (but not always) used in tandem: 1129<p>Prepare and check watchers are usually (but not always) used in tandem:
1105prepare watchers get invoked before the process blocks and check watchers 1130prepare watchers get invoked before the process blocks and check watchers
1106afterwards.</p> 1131afterwards.</p>
1132<p>You <i>must not</i> call <code>ev_loop</code> or similar functions that enter
1133the current event loop from either <code>ev_prepare</code> or <code>ev_check</code>
1134watchers. Other loops than the current one are fine, however. The
1135rationale behind this is that you do not need to check for recursion in
1136those watchers, i.e. the sequence will always be <code>ev_prepare</code>, blocking,
1137<code>ev_check</code> so if you have one watcher of each kind they will always be
1138called in pairs bracketing the blocking call.</p>
1107<p>Their main purpose is to integrate other event mechanisms into libev and 1139<p>Their main purpose is to integrate other event mechanisms into libev and
1108their use is somewhat advanced. This could be used, for example, to track 1140their use is somewhat advanced. This could be used, for example, to track
1109variable changes, implement your own watchers, integrate net-snmp or a 1141variable changes, implement your own watchers, integrate net-snmp or a
1110coroutine library and lots more.</p> 1142coroutine library and lots more. They are also occasionally useful if
1143you cache some data and want to flush it before blocking (for example,
1144in X programs you might want to do an <code>XFlush ()</code> in an <code>ev_prepare</code>
1145watcher).</p>
1111<p>This is done by examining in each prepare call which file descriptors need 1146<p>This is done by examining in each prepare call which file descriptors need
1112to be watched by the other library, registering <code>ev_io</code> watchers for 1147to be watched by the other library, registering <code>ev_io</code> watchers for
1113them and starting an <code>ev_timer</code> watcher for any timeouts (many libraries 1148them and starting an <code>ev_timer</code> watcher for any timeouts (many libraries
1114provide just this functionality). Then, in the check watcher you check for 1149provide just this functionality). Then, in the check watcher you check for
1115any events that occured (by checking the pending status of all watchers 1150any events that occured (by checking the pending status of all watchers
… …
1131 <p>Initialises and configures the prepare or check watcher - they have no 1166 <p>Initialises and configures the prepare or check watcher - they have no
1132parameters of any kind. There are <code>ev_prepare_set</code> and <code>ev_check_set</code> 1167parameters of any kind. There are <code>ev_prepare_set</code> and <code>ev_check_set</code>
1133macros, but using them is utterly, utterly and completely pointless.</p> 1168macros, but using them is utterly, utterly and completely pointless.</p>
1134 </dd> 1169 </dd>
1135</dl> 1170</dl>
1136<p>Example: *TODO*.</p> 1171<p>Example: To include a library such as adns, you would add IO watchers
1172and a timeout watcher in a prepare handler, as required by libadns, and
1173in a check watcher, destroy them and call into libadns. What follows is
1174pseudo-code only of course:</p>
1175<pre> static ev_io iow [nfd];
1176 static ev_timer tw;
1137 1177
1178 static void
1179 io_cb (ev_loop *loop, ev_io *w, int revents)
1180 {
1181 // set the relevant poll flags
1182 // could also call adns_processreadable etc. here
1183 struct pollfd *fd = (struct pollfd *)w-&gt;data;
1184 if (revents &amp; EV_READ ) fd-&gt;revents |= fd-&gt;events &amp; POLLIN;
1185 if (revents &amp; EV_WRITE) fd-&gt;revents |= fd-&gt;events &amp; POLLOUT;
1186 }
1138 1187
1188 // create io watchers for each fd and a timer before blocking
1189 static void
1190 adns_prepare_cb (ev_loop *loop, ev_prepare *w, int revents)
1191 {
1192 int timeout = 3600000;truct pollfd fds [nfd];
1193 // actual code will need to loop here and realloc etc.
1194 adns_beforepoll (ads, fds, &amp;nfd, &amp;timeout, timeval_from (ev_time ()));
1139 1195
1196 /* the callback is illegal, but won't be called as we stop during check */
1197 ev_timer_init (&amp;tw, 0, timeout * 1e-3);
1198 ev_timer_start (loop, &amp;tw);
1140 1199
1200 // create on ev_io per pollfd
1201 for (int i = 0; i &lt; nfd; ++i)
1202 {
1203 ev_io_init (iow + i, io_cb, fds [i].fd,
1204 ((fds [i].events &amp; POLLIN ? EV_READ : 0)
1205 | (fds [i].events &amp; POLLOUT ? EV_WRITE : 0)));
1141 1206
1207 fds [i].revents = 0;
1208 iow [i].data = fds + i;
1209 ev_io_start (loop, iow + i);
1210 }
1211 }
1212
1213 // stop all watchers after blocking
1214 static void
1215 adns_check_cb (ev_loop *loop, ev_check *w, int revents)
1216 {
1217 ev_timer_stop (loop, &amp;tw);
1218
1219 for (int i = 0; i &lt; nfd; ++i)
1220 ev_io_stop (loop, iow + i);
1221
1222 adns_afterpoll (adns, fds, nfd, timeval_from (ev_now (loop));
1223 }
1224
1225
1226
1227
1228</pre>
1229
1142</div> 1230</div>
1143<h2 id="code_ev_embed_code_when_one_backend_"><code>ev_embed</code> - when one backend isn't enough</h2> 1231<h2 id="code_ev_embed_code_when_one_backend_"><code>ev_embed</code> - when one backend isn't enough...</h2>
1144<div id="code_ev_embed_code_when_one_backend_-2"> 1232<div id="code_ev_embed_code_when_one_backend_-2">
1145<p>This is a rather advanced watcher type that lets you embed one event loop 1233<p>This is a rather advanced watcher type that lets you embed one event loop
1146into another (currently only <code>ev_io</code> events are supported in the embedded 1234into another (currently only <code>ev_io</code> events are supported in the embedded
1147loop, other types of watchers might be handled in a delayed or incorrect 1235loop, other types of watchers might be handled in a delayed or incorrect
1148fashion and must not be used).</p> 1236fashion and must not be used).</p>
… …
1302</dl> 1390</dl>
1303 1391
1304</div> 1392</div>
1305<h1 id="C_SUPPORT">C++ SUPPORT</h1><p><a href="#TOP" class="toplink">Top</a></p> 1393<h1 id="C_SUPPORT">C++ SUPPORT</h1><p><a href="#TOP" class="toplink">Top</a></p>
1306<div id="C_SUPPORT_CONTENT"> 1394<div id="C_SUPPORT_CONTENT">
1307<p>TBD.</p> 1395<p>Libev comes with some simplistic wrapper classes for C++ that mainly allow
1396you to use some convinience methods to start/stop watchers and also change
1397the callback model to a model using method callbacks on objects.</p>
1398<p>To use it,</p>
1399<pre> #include &lt;ev++.h&gt;
1400
1401</pre>
1402<p>(it is not installed by default). This automatically includes <cite>ev.h</cite>
1403and puts all of its definitions (many of them macros) into the global
1404namespace. All C++ specific things are put into the <code>ev</code> namespace.</p>
1405<p>It should support all the same embedding options as <cite>ev.h</cite>, most notably
1406<code>EV_MULTIPLICITY</code>.</p>
1407<p>Here is a list of things available in the <code>ev</code> namespace:</p>
1408<dl>
1409 <dt><code>ev::READ</code>, <code>ev::WRITE</code> etc.</dt>
1410 <dd>
1411 <p>These are just enum values with the same values as the <code>EV_READ</code> etc.
1412macros from <cite>ev.h</cite>.</p>
1413 </dd>
1414 <dt><code>ev::tstamp</code>, <code>ev::now</code></dt>
1415 <dd>
1416 <p>Aliases to the same types/functions as with the <code>ev_</code> prefix.</p>
1417 </dd>
1418 <dt><code>ev::io</code>, <code>ev::timer</code>, <code>ev::periodic</code>, <code>ev::idle</code>, <code>ev::sig</code> etc.</dt>
1419 <dd>
1420 <p>For each <code>ev_TYPE</code> watcher in <cite>ev.h</cite> there is a corresponding class of
1421the same name in the <code>ev</code> namespace, with the exception of <code>ev_signal</code>
1422which is called <code>ev::sig</code> to avoid clashes with the <code>signal</code> macro
1423defines by many implementations.</p>
1424 <p>All of those classes have these methods:</p>
1425 <p>
1426 <dl>
1427 <dt>ev::TYPE::TYPE (object *, object::method *)</dt>
1428 <dt>ev::TYPE::TYPE (object *, object::method *, struct ev_loop *)</dt>
1429 <dt>ev::TYPE::~TYPE</dt>
1430 <dd>
1431 <p>The constructor takes a pointer to an object and a method pointer to
1432the event handler callback to call in this class. The constructor calls
1433<code>ev_init</code> for you, which means you have to call the <code>set</code> method
1434before starting it. If you do not specify a loop then the constructor
1435automatically associates the default loop with this watcher.</p>
1436 <p>The destructor automatically stops the watcher if it is active.</p>
1437 </dd>
1438 <dt>w-&gt;set (struct ev_loop *)</dt>
1439 <dd>
1440 <p>Associates a different <code>struct ev_loop</code> with this watcher. You can only
1441do this when the watcher is inactive (and not pending either).</p>
1442 </dd>
1443 <dt>w-&gt;set ([args])</dt>
1444 <dd>
1445 <p>Basically the same as <code>ev_TYPE_set</code>, with the same args. Must be
1446called at least once. Unlike the C counterpart, an active watcher gets
1447automatically stopped and restarted.</p>
1448 </dd>
1449 <dt>w-&gt;start ()</dt>
1450 <dd>
1451 <p>Starts the watcher. Note that there is no <code>loop</code> argument as the
1452constructor already takes the loop.</p>
1453 </dd>
1454 <dt>w-&gt;stop ()</dt>
1455 <dd>
1456 <p>Stops the watcher if it is active. Again, no <code>loop</code> argument.</p>
1457 </dd>
1458 <dt>w-&gt;again () <code>ev::timer</code>, <code>ev::periodic</code> only</dt>
1459 <dd>
1460 <p>For <code>ev::timer</code> and <code>ev::periodic</code>, this invokes the corresponding
1461<code>ev_TYPE_again</code> function.</p>
1462 </dd>
1463 <dt>w-&gt;sweep () <code>ev::embed</code> only</dt>
1464 <dd>
1465 <p>Invokes <code>ev_embed_sweep</code>.</p>
1466 </dd>
1467 </dl>
1468 </p>
1469 </dd>
1470</dl>
1471<p>Example: Define a class with an IO and idle watcher, start one of them in
1472the constructor.</p>
1473<pre> class myclass
1474 {
1475 ev_io io; void io_cb (ev::io &amp;w, int revents);
1476 ev_idle idle void idle_cb (ev::idle &amp;w, int revents);
1477
1478 myclass ();
1479 }
1480
1481 myclass::myclass (int fd)
1482 : io (this, &amp;myclass::io_cb),
1483 idle (this, &amp;myclass::idle_cb)
1484 {
1485 io.start (fd, ev::READ);
1486 }
1487
1488</pre>
1489
1490</div>
1491<h1 id="EMBEDDING">EMBEDDING</h1><p><a href="#TOP" class="toplink">Top</a></p>
1492<div id="EMBEDDING_CONTENT">
1493<p>Libev can (and often is) directly embedded into host
1494applications. Examples of applications that embed it include the Deliantra
1495Game Server, the EV perl module, the GNU Virtual Private Ethernet (gvpe)
1496and rxvt-unicode.</p>
1497<p>The goal is to enable you to just copy the neecssary files into your
1498source directory without having to change even a single line in them, so
1499you can easily upgrade by simply copying (or having a checked-out copy of
1500libev somewhere in your source tree).</p>
1501
1502</div>
1503<h2 id="FILESETS">FILESETS</h2>
1504<div id="FILESETS_CONTENT">
1505<p>Depending on what features you need you need to include one or more sets of files
1506in your app.</p>
1507
1508</div>
1509<h3 id="CORE_EVENT_LOOP">CORE EVENT LOOP</h3>
1510<div id="CORE_EVENT_LOOP_CONTENT">
1511<p>To include only the libev core (all the <code>ev_*</code> functions), with manual
1512configuration (no autoconf):</p>
1513<pre> #define EV_STANDALONE 1
1514 #include &quot;ev.c&quot;
1515
1516</pre>
1517<p>This will automatically include <cite>ev.h</cite>, too, and should be done in a
1518single C source file only to provide the function implementations. To use
1519it, do the same for <cite>ev.h</cite> in all files wishing to use this API (best
1520done by writing a wrapper around <cite>ev.h</cite> that you can include instead and
1521where you can put other configuration options):</p>
1522<pre> #define EV_STANDALONE 1
1523 #include &quot;ev.h&quot;
1524
1525</pre>
1526<p>Both header files and implementation files can be compiled with a C++
1527compiler (at least, thats a stated goal, and breakage will be treated
1528as a bug).</p>
1529<p>You need the following files in your source tree, or in a directory
1530in your include path (e.g. in libev/ when using -Ilibev):</p>
1531<pre> ev.h
1532 ev.c
1533 ev_vars.h
1534 ev_wrap.h
1535
1536 ev_win32.c required on win32 platforms only
1537
1538 ev_select.c only when select backend is enabled (which is by default)
1539 ev_poll.c only when poll backend is enabled (disabled by default)
1540 ev_epoll.c only when the epoll backend is enabled (disabled by default)
1541 ev_kqueue.c only when the kqueue backend is enabled (disabled by default)
1542 ev_port.c only when the solaris port backend is enabled (disabled by default)
1543
1544</pre>
1545<p><cite>ev.c</cite> includes the backend files directly when enabled, so you only need
1546to compile this single file.</p>
1547
1548</div>
1549<h3 id="LIBEVENT_COMPATIBILITY_API">LIBEVENT COMPATIBILITY API</h3>
1550<div id="LIBEVENT_COMPATIBILITY_API_CONTENT">
1551<p>To include the libevent compatibility API, also include:</p>
1552<pre> #include &quot;event.c&quot;
1553
1554</pre>
1555<p>in the file including <cite>ev.c</cite>, and:</p>
1556<pre> #include &quot;event.h&quot;
1557
1558</pre>
1559<p>in the files that want to use the libevent API. This also includes <cite>ev.h</cite>.</p>
1560<p>You need the following additional files for this:</p>
1561<pre> event.h
1562 event.c
1563
1564</pre>
1565
1566</div>
1567<h3 id="AUTOCONF_SUPPORT">AUTOCONF SUPPORT</h3>
1568<div id="AUTOCONF_SUPPORT_CONTENT">
1569<p>Instead of using <code>EV_STANDALONE=1</code> and providing your config in
1570whatever way you want, you can also <code>m4_include([libev.m4])</code> in your
1571<cite>configure.ac</cite> and leave <code>EV_STANDALONE</code> undefined. <cite>ev.c</cite> will then
1572include <cite>config.h</cite> and configure itself accordingly.</p>
1573<p>For this of course you need the m4 file:</p>
1574<pre> libev.m4
1575
1576</pre>
1577
1578</div>
1579<h2 id="PREPROCESSOR_SYMBOLS_MACROS">PREPROCESSOR SYMBOLS/MACROS</h2>
1580<div id="PREPROCESSOR_SYMBOLS_MACROS_CONTENT">
1581<p>Libev can be configured via a variety of preprocessor symbols you have to define
1582before including any of its files. The default is not to build for multiplicity
1583and only include the select backend.</p>
1584<dl>
1585 <dt>EV_STANDALONE</dt>
1586 <dd>
1587 <p>Must always be <code>1</code> if you do not use autoconf configuration, which
1588keeps libev from including <cite>config.h</cite>, and it also defines dummy
1589implementations for some libevent functions (such as logging, which is not
1590supported). It will also not define any of the structs usually found in
1591<cite>event.h</cite> that are not directly supported by the libev core alone.</p>
1592 </dd>
1593 <dt>EV_USE_MONOTONIC</dt>
1594 <dd>
1595 <p>If defined to be <code>1</code>, libev will try to detect the availability of the
1596monotonic clock option at both compiletime and runtime. Otherwise no use
1597of the monotonic clock option will be attempted. If you enable this, you
1598usually have to link against librt or something similar. Enabling it when
1599the functionality isn't available is safe, though, althoguh you have
1600to make sure you link against any libraries where the <code>clock_gettime</code>
1601function is hiding in (often <cite>-lrt</cite>).</p>
1602 </dd>
1603 <dt>EV_USE_REALTIME</dt>
1604 <dd>
1605 <p>If defined to be <code>1</code>, libev will try to detect the availability of the
1606realtime clock option at compiletime (and assume its availability at
1607runtime if successful). Otherwise no use of the realtime clock option will
1608be attempted. This effectively replaces <code>gettimeofday</code> by <code>clock_get
1609(CLOCK_REALTIME, ...)</code> and will not normally affect correctness. See tzhe note about libraries
1610in the description of <code>EV_USE_MONOTONIC</code>, though.</p>
1611 </dd>
1612 <dt>EV_USE_SELECT</dt>
1613 <dd>
1614 <p>If undefined or defined to be <code>1</code>, libev will compile in support for the
1615<code>select</code>(2) backend. No attempt at autodetection will be done: if no
1616other method takes over, select will be it. Otherwise the select backend
1617will not be compiled in.</p>
1618 </dd>
1619 <dt>EV_SELECT_USE_FD_SET</dt>
1620 <dd>
1621 <p>If defined to <code>1</code>, then the select backend will use the system <code>fd_set</code>
1622structure. This is useful if libev doesn't compile due to a missing
1623<code>NFDBITS</code> or <code>fd_mask</code> definition or it misguesses the bitset layout on
1624exotic systems. This usually limits the range of file descriptors to some
1625low limit such as 1024 or might have other limitations (winsocket only
1626allows 64 sockets). The <code>FD_SETSIZE</code> macro, set before compilation, might
1627influence the size of the <code>fd_set</code> used.</p>
1628 </dd>
1629 <dt>EV_SELECT_IS_WINSOCKET</dt>
1630 <dd>
1631 <p>When defined to <code>1</code>, the select backend will assume that
1632select/socket/connect etc. don't understand file descriptors but
1633wants osf handles on win32 (this is the case when the select to
1634be used is the winsock select). This means that it will call
1635<code>_get_osfhandle</code> on the fd to convert it to an OS handle. Otherwise,
1636it is assumed that all these functions actually work on fds, even
1637on win32. Should not be defined on non-win32 platforms.</p>
1638 </dd>
1639 <dt>EV_USE_POLL</dt>
1640 <dd>
1641 <p>If defined to be <code>1</code>, libev will compile in support for the <code>poll</code>(2)
1642backend. Otherwise it will be enabled on non-win32 platforms. It
1643takes precedence over select.</p>
1644 </dd>
1645 <dt>EV_USE_EPOLL</dt>
1646 <dd>
1647 <p>If defined to be <code>1</code>, libev will compile in support for the Linux
1648<code>epoll</code>(7) backend. Its availability will be detected at runtime,
1649otherwise another method will be used as fallback. This is the
1650preferred backend for GNU/Linux systems.</p>
1651 </dd>
1652 <dt>EV_USE_KQUEUE</dt>
1653 <dd>
1654 <p>If defined to be <code>1</code>, libev will compile in support for the BSD style
1655<code>kqueue</code>(2) backend. Its actual availability will be detected at runtime,
1656otherwise another method will be used as fallback. This is the preferred
1657backend for BSD and BSD-like systems, although on most BSDs kqueue only
1658supports some types of fds correctly (the only platform we found that
1659supports ptys for example was NetBSD), so kqueue might be compiled in, but
1660not be used unless explicitly requested. The best way to use it is to find
1661out whether kqueue supports your type of fd properly and use an embedded
1662kqueue loop.</p>
1663 </dd>
1664 <dt>EV_USE_PORT</dt>
1665 <dd>
1666 <p>If defined to be <code>1</code>, libev will compile in support for the Solaris
166710 port style backend. Its availability will be detected at runtime,
1668otherwise another method will be used as fallback. This is the preferred
1669backend for Solaris 10 systems.</p>
1670 </dd>
1671 <dt>EV_USE_DEVPOLL</dt>
1672 <dd>
1673 <p>reserved for future expansion, works like the USE symbols above.</p>
1674 </dd>
1675 <dt>EV_H</dt>
1676 <dd>
1677 <p>The name of the <cite>ev.h</cite> header file used to include it. The default if
1678undefined is <code>&lt;ev.h&gt;</code> in <cite>event.h</cite> and <code>&quot;ev.h&quot;</code> in <cite>ev.c</cite>. This
1679can be used to virtually rename the <cite>ev.h</cite> header file in case of conflicts.</p>
1680 </dd>
1681 <dt>EV_CONFIG_H</dt>
1682 <dd>
1683 <p>If <code>EV_STANDALONE</code> isn't <code>1</code>, this variable can be used to override
1684<cite>ev.c</cite>'s idea of where to find the <cite>config.h</cite> file, similarly to
1685<code>EV_H</code>, above.</p>
1686 </dd>
1687 <dt>EV_EVENT_H</dt>
1688 <dd>
1689 <p>Similarly to <code>EV_H</code>, this macro can be used to override <cite>event.c</cite>'s idea
1690of how the <cite>event.h</cite> header can be found.</p>
1691 </dd>
1692 <dt>EV_PROTOTYPES</dt>
1693 <dd>
1694 <p>If defined to be <code>0</code>, then <cite>ev.h</cite> will not define any function
1695prototypes, but still define all the structs and other symbols. This is
1696occasionally useful if you want to provide your own wrapper functions
1697around libev functions.</p>
1698 </dd>
1699 <dt>EV_MULTIPLICITY</dt>
1700 <dd>
1701 <p>If undefined or defined to <code>1</code>, then all event-loop-specific functions
1702will have the <code>struct ev_loop *</code> as first argument, and you can create
1703additional independent event loops. Otherwise there will be no support
1704for multiple event loops and there is no first event loop pointer
1705argument. Instead, all functions act on the single default loop.</p>
1706 </dd>
1707 <dt>EV_PERIODICS</dt>
1708 <dd>
1709 <p>If undefined or defined to be <code>1</code>, then periodic timers are supported,
1710otherwise not. This saves a few kb of code.</p>
1711 </dd>
1712 <dt>EV_COMMON</dt>
1713 <dd>
1714 <p>By default, all watchers have a <code>void *data</code> member. By redefining
1715this macro to a something else you can include more and other types of
1716members. You have to define it each time you include one of the files,
1717though, and it must be identical each time.</p>
1718 <p>For example, the perl EV module uses something like this:</p>
1719<pre> #define EV_COMMON \
1720 SV *self; /* contains this struct */ \
1721 SV *cb_sv, *fh /* note no trailing &quot;;&quot; */
1722
1723</pre>
1724 </dd>
1725 <dt>EV_CB_DECLARE (type)</dt>
1726 <dt>EV_CB_INVOKE (watcher, revents)</dt>
1727 <dt>ev_set_cb (ev, cb)</dt>
1728 <dd>
1729 <p>Can be used to change the callback member declaration in each watcher,
1730and the way callbacks are invoked and set. Must expand to a struct member
1731definition and a statement, respectively. See the <cite>ev.v</cite> header file for
1732their default definitions. One possible use for overriding these is to
1733avoid the <code>struct ev_loop *</code> as first argument in all cases, or to use
1734method calls instead of plain function calls in C++.</p>
1735
1736</div>
1737<h2 id="EXAMPLES">EXAMPLES</h2>
1738<div id="EXAMPLES_CONTENT">
1739 <p>For a real-world example of a program the includes libev
1740verbatim, you can have a look at the EV perl module
1741(<a href="http://software.schmorp.de/pkg/EV.html">http://software.schmorp.de/pkg/EV.html</a>). It has the libev files in
1742the <cite>libev/</cite> subdirectory and includes them in the <cite>EV/EVAPI.h</cite> (public
1743interface) and <cite>EV.xs</cite> (implementation) files. Only the <cite>EV.xs</cite> file
1744will be compiled. It is pretty complex because it provides its own header
1745file.</p>
1746 <p>The usage in rxvt-unicode is simpler. It has a <cite>ev_cpp.h</cite> header file
1747that everybody includes and which overrides some autoconf choices:</p>
1748<pre> #define EV_USE_POLL 0
1749 #define EV_MULTIPLICITY 0
1750 #define EV_PERIODICS 0
1751 #define EV_CONFIG_H &lt;config.h&gt;
1752
1753 #include &quot;ev++.h&quot;
1754
1755</pre>
1756 <p>And a <cite>ev_cpp.C</cite> implementation file that contains libev proper and is compiled:</p>
1757<pre> #include &quot;ev_cpp.h&quot;
1758 #include &quot;ev.c&quot;
1759
1760
1761
1762
1763</pre>
1764
1765</div>
1766<h1 id="COMPLEXITIES">COMPLEXITIES</h1><p><a href="#TOP" class="toplink">Top</a></p>
1767<div id="COMPLEXITIES_CONTENT">
1768 <p>In this section the complexities of (many of) the algorithms used inside
1769libev will be explained. For complexity discussions about backends see the
1770documentation for <code>ev_default_init</code>.</p>
1771 <p>
1772 <dl>
1773 <dt>Starting and stopping timer/periodic watchers: O(log skipped_other_timers)</dt>
1774 <dt>Changing timer/periodic watchers (by autorepeat, again): O(log skipped_other_timers)</dt>
1775 <dt>Starting io/check/prepare/idle/signal/child watchers: O(1)</dt>
1776 <dt>Stopping check/prepare/idle watchers: O(1)</dt>
1777 <dt>Stopping an io/signal/child watcher: O(number_of_watchers_for_this_(fd/signal/pid % 16))</dt>
1778 <dt>Finding the next timer per loop iteration: O(1)</dt>
1779 <dt>Each change on a file descriptor per loop iteration: O(number_of_watchers_for_this_fd)</dt>
1780 <dt>Activating one watcher: O(1)</dt>
1781 </dl>
1782 </p>
1783
1784
1785
1786
1308 1787
1309</div> 1788</div>
1310<h1 id="AUTHOR">AUTHOR</h1><p><a href="#TOP" class="toplink">Top</a></p> 1789<h1 id="AUTHOR">AUTHOR</h1><p><a href="#TOP" class="toplink">Top</a></p>
1311<div id="AUTHOR_CONTENT"> 1790<div id="AUTHOR_CONTENT">
1312<p>Marc Lehmann &lt;libev@schmorp.de&gt;.</p> 1791 <p>Marc Lehmann &lt;libev@schmorp.de&gt;.</p>
1313 1792
1314</div> 1793</div>
1315</div></body> 1794</div></body>
1316</html> 1795</html>

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