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Comparing libev/ev.pod (file contents):
Revision 1.81 by root, Wed Dec 12 04:53:58 2007 UTC vs.
Revision 1.86 by root, Tue Dec 18 01:20:33 2007 UTC

98Libev represents time as a single floating point number, representing the 98Libev represents time as a single floating point number, representing the
99(fractional) number of seconds since the (POSIX) epoch (somewhere near 99(fractional) number of seconds since the (POSIX) epoch (somewhere near
100the beginning of 1970, details are complicated, don't ask). This type is 100the beginning of 1970, details are complicated, don't ask). This type is
101called C<ev_tstamp>, which is what you should use too. It usually aliases 101called C<ev_tstamp>, which is what you should use too. It usually aliases
102to the C<double> type in C, and when you need to do any calculations on 102to the C<double> type in C, and when you need to do any calculations on
103it, you should treat it as such. 103it, you should treat it as some floatingpoint value. Unlike the name
104component C<stamp> might indicate, it is also used for time differences
105throughout libev.
104 106
105=head1 GLOBAL FUNCTIONS 107=head1 GLOBAL FUNCTIONS
106 108
107These functions can be called anytime, even before initialising the 109These functions can be called anytime, even before initialising the
108library in any way. 110library in any way.
933This is how one would do it normally anyway, the important point is that 935This is how one would do it normally anyway, the important point is that
934the libev application should not optimise around libev but should leave 936the libev application should not optimise around libev but should leave
935optimisations to libev. 937optimisations to libev.
936 938
937 939
940=head3 Watcher-Specific Functions
941
938=over 4 942=over 4
939 943
940=item ev_io_init (ev_io *, callback, int fd, int events) 944=item ev_io_init (ev_io *, callback, int fd, int events)
941 945
942=item ev_io_set (ev_io *, int fd, int events) 946=item ev_io_set (ev_io *, int fd, int events)
994 ev_timer_set (&timer, after + ev_now () - ev_time (), 0.); 998 ev_timer_set (&timer, after + ev_now () - ev_time (), 0.);
995 999
996The callback is guarenteed to be invoked only when its timeout has passed, 1000The callback is guarenteed to be invoked only when its timeout has passed,
997but if multiple timers become ready during the same loop iteration then 1001but if multiple timers become ready during the same loop iteration then
998order of execution is undefined. 1002order of execution is undefined.
1003
1004=head3 Watcher-Specific Functions and Data Members
999 1005
1000=over 4 1006=over 4
1001 1007
1002=item ev_timer_init (ev_timer *, callback, ev_tstamp after, ev_tstamp repeat) 1008=item ev_timer_init (ev_timer *, callback, ev_tstamp after, ev_tstamp repeat)
1003 1009
1109 1115
1110As with timers, the callback is guarenteed to be invoked only when the 1116As with timers, the callback is guarenteed to be invoked only when the
1111time (C<at>) has been passed, but if multiple periodic timers become ready 1117time (C<at>) has been passed, but if multiple periodic timers become ready
1112during the same loop iteration then order of execution is undefined. 1118during the same loop iteration then order of execution is undefined.
1113 1119
1120=head3 Watcher-Specific Functions and Data Members
1121
1114=over 4 1122=over 4
1115 1123
1116=item ev_periodic_init (ev_periodic *, callback, ev_tstamp at, ev_tstamp interval, reschedule_cb) 1124=item ev_periodic_init (ev_periodic *, callback, ev_tstamp at, ev_tstamp interval, reschedule_cb)
1117 1125
1118=item ev_periodic_set (ev_periodic *, ev_tstamp after, ev_tstamp repeat, reschedule_cb) 1126=item ev_periodic_set (ev_periodic *, ev_tstamp after, ev_tstamp repeat, reschedule_cb)
1213=item ev_tstamp (*reschedule_cb)(struct ev_periodic *w, ev_tstamp now) [read-write] 1221=item ev_tstamp (*reschedule_cb)(struct ev_periodic *w, ev_tstamp now) [read-write]
1214 1222
1215The current reschedule callback, or C<0>, if this functionality is 1223The current reschedule callback, or C<0>, if this functionality is
1216switched off. Can be changed any time, but changes only take effect when 1224switched off. Can be changed any time, but changes only take effect when
1217the periodic timer fires or C<ev_periodic_again> is being called. 1225the periodic timer fires or C<ev_periodic_again> is being called.
1226
1227=item ev_tstamp at [read-only]
1228
1229When active, contains the absolute time that the watcher is supposed to
1230trigger next.
1218 1231
1219=back 1232=back
1220 1233
1221Example: Call a callback every hour, or, more precisely, whenever the 1234Example: Call a callback every hour, or, more precisely, whenever the
1222system clock is divisible by 3600. The callback invocation times have 1235system clock is divisible by 3600. The callback invocation times have
1264with the kernel (thus it coexists with your own signal handlers as long 1277with the kernel (thus it coexists with your own signal handlers as long
1265as you don't register any with libev). Similarly, when the last signal 1278as you don't register any with libev). Similarly, when the last signal
1266watcher for a signal is stopped libev will reset the signal handler to 1279watcher for a signal is stopped libev will reset the signal handler to
1267SIG_DFL (regardless of what it was set to before). 1280SIG_DFL (regardless of what it was set to before).
1268 1281
1282=head3 Watcher-Specific Functions and Data Members
1283
1269=over 4 1284=over 4
1270 1285
1271=item ev_signal_init (ev_signal *, callback, int signum) 1286=item ev_signal_init (ev_signal *, callback, int signum)
1272 1287
1273=item ev_signal_set (ev_signal *, int signum) 1288=item ev_signal_set (ev_signal *, int signum)
1284 1299
1285=head2 C<ev_child> - watch out for process status changes 1300=head2 C<ev_child> - watch out for process status changes
1286 1301
1287Child watchers trigger when your process receives a SIGCHLD in response to 1302Child watchers trigger when your process receives a SIGCHLD in response to
1288some child status changes (most typically when a child of yours dies). 1303some child status changes (most typically when a child of yours dies).
1304
1305=head3 Watcher-Specific Functions and Data Members
1289 1306
1290=over 4 1307=over 4
1291 1308
1292=item ev_child_init (ev_child *, callback, int pid) 1309=item ev_child_init (ev_child *, callback, int pid)
1293 1310
1361reader). Inotify will be used to give hints only and should not change the 1378reader). Inotify will be used to give hints only and should not change the
1362semantics of C<ev_stat> watchers, which means that libev sometimes needs 1379semantics of C<ev_stat> watchers, which means that libev sometimes needs
1363to fall back to regular polling again even with inotify, but changes are 1380to fall back to regular polling again even with inotify, but changes are
1364usually detected immediately, and if the file exists there will be no 1381usually detected immediately, and if the file exists there will be no
1365polling. 1382polling.
1383
1384=head3 Watcher-Specific Functions and Data Members
1366 1385
1367=over 4 1386=over 4
1368 1387
1369=item ev_stat_init (ev_stat *, callback, const char *path, ev_tstamp interval) 1388=item ev_stat_init (ev_stat *, callback, const char *path, ev_tstamp interval)
1370 1389
1453Apart from keeping your process non-blocking (which is a useful 1472Apart from keeping your process non-blocking (which is a useful
1454effect on its own sometimes), idle watchers are a good place to do 1473effect on its own sometimes), idle watchers are a good place to do
1455"pseudo-background processing", or delay processing stuff to after the 1474"pseudo-background processing", or delay processing stuff to after the
1456event loop has handled all outstanding events. 1475event loop has handled all outstanding events.
1457 1476
1477=head3 Watcher-Specific Functions and Data Members
1478
1458=over 4 1479=over 4
1459 1480
1460=item ev_idle_init (ev_signal *, callback) 1481=item ev_idle_init (ev_signal *, callback)
1461 1482
1462Initialises and configures the idle watcher - it has no parameters of any 1483Initialises and configures the idle watcher - it has no parameters of any
1529their job. As C<ev_check> watchers are often used to embed other event 1550their job. As C<ev_check> watchers are often used to embed other event
1530loops those other event loops might be in an unusable state until their 1551loops those other event loops might be in an unusable state until their
1531C<ev_check> watcher ran (always remind yourself to coexist peacefully with 1552C<ev_check> watcher ran (always remind yourself to coexist peacefully with
1532others). 1553others).
1533 1554
1555=head3 Watcher-Specific Functions and Data Members
1556
1534=over 4 1557=over 4
1535 1558
1536=item ev_prepare_init (ev_prepare *, callback) 1559=item ev_prepare_init (ev_prepare *, callback)
1537 1560
1538=item ev_check_init (ev_check *, callback) 1561=item ev_check_init (ev_check *, callback)
1739 ev_embed_start (loop_hi, &embed); 1762 ev_embed_start (loop_hi, &embed);
1740 } 1763 }
1741 else 1764 else
1742 loop_lo = loop_hi; 1765 loop_lo = loop_hi;
1743 1766
1767=head3 Watcher-Specific Functions and Data Members
1768
1744=over 4 1769=over 4
1745 1770
1746=item ev_embed_init (ev_embed *, callback, struct ev_loop *embedded_loop) 1771=item ev_embed_init (ev_embed *, callback, struct ev_loop *embedded_loop)
1747 1772
1748=item ev_embed_set (ev_embed *, callback, struct ev_loop *embedded_loop) 1773=item ev_embed_set (ev_embed *, callback, struct ev_loop *embedded_loop)
1774event loop blocks next and before C<ev_check> watchers are being called, 1799event loop blocks next and before C<ev_check> watchers are being called,
1775and only in the child after the fork. If whoever good citizen calling 1800and only in the child after the fork. If whoever good citizen calling
1776C<ev_default_fork> cheats and calls it in the wrong process, the fork 1801C<ev_default_fork> cheats and calls it in the wrong process, the fork
1777handlers will be invoked, too, of course. 1802handlers will be invoked, too, of course.
1778 1803
1804=head3 Watcher-Specific Functions and Data Members
1805
1779=over 4 1806=over 4
1780 1807
1781=item ev_fork_init (ev_signal *, callback) 1808=item ev_fork_init (ev_signal *, callback)
1782 1809
1783Initialises and configures the fork watcher - it has no parameters of any 1810Initialises and configures the fork watcher - it has no parameters of any
1999 2026
2000=item w->stop () 2027=item w->stop ()
2001 2028
2002Stops the watcher if it is active. Again, no C<loop> argument. 2029Stops the watcher if it is active. Again, no C<loop> argument.
2003 2030
2004=item w->again () C<ev::timer>, C<ev::periodic> only 2031=item w->again () (C<ev::timer>, C<ev::periodic> only)
2005 2032
2006For C<ev::timer> and C<ev::periodic>, this invokes the corresponding 2033For C<ev::timer> and C<ev::periodic>, this invokes the corresponding
2007C<ev_TYPE_again> function. 2034C<ev_TYPE_again> function.
2008 2035
2009=item w->sweep () C<ev::embed> only 2036=item w->sweep () (C<ev::embed> only)
2010 2037
2011Invokes C<ev_embed_sweep>. 2038Invokes C<ev_embed_sweep>.
2012 2039
2013=item w->update () C<ev::stat> only 2040=item w->update () (C<ev::stat> only)
2014 2041
2015Invokes C<ev_stat_stat>. 2042Invokes C<ev_stat_stat>.
2016 2043
2017=back 2044=back
2018 2045
2038 } 2065 }
2039 2066
2040 2067
2041=head1 MACRO MAGIC 2068=head1 MACRO MAGIC
2042 2069
2043Libev can be compiled with a variety of options, the most fundemantal is 2070Libev can be compiled with a variety of options, the most fundamantal
2044C<EV_MULTIPLICITY>. This option determines whether (most) functions and 2071of which is C<EV_MULTIPLICITY>. This option determines whether (most)
2045callbacks have an initial C<struct ev_loop *> argument. 2072functions and callbacks have an initial C<struct ev_loop *> argument.
2046 2073
2047To make it easier to write programs that cope with either variant, the 2074To make it easier to write programs that cope with either variant, the
2048following macros are defined: 2075following macros are defined:
2049 2076
2050=over 4 2077=over 4

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