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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 1.85 by root, Mon Dec 17 07:24:12 2007 UTC

933This is how one would do it normally anyway, the important point is that 933This is how one would do it normally anyway, the important point is that
934the libev application should not optimise around libev but should leave 934the libev application should not optimise around libev but should leave
935optimisations to libev. 935optimisations to libev.
936 936
937 937
938=head3 Watcher-Specific Functions
939
938=over 4 940=over 4
939 941
940=item ev_io_init (ev_io *, callback, int fd, int events) 942=item ev_io_init (ev_io *, callback, int fd, int events)
941 943
942=item ev_io_set (ev_io *, int fd, int events) 944=item ev_io_set (ev_io *, int fd, int events)
994 ev_timer_set (&timer, after + ev_now () - ev_time (), 0.); 996 ev_timer_set (&timer, after + ev_now () - ev_time (), 0.);
995 997
996The callback is guarenteed to be invoked only when its timeout has passed, 998The callback is guarenteed to be invoked only when its timeout has passed,
997but if multiple timers become ready during the same loop iteration then 999but if multiple timers become ready during the same loop iteration then
998order of execution is undefined. 1000order of execution is undefined.
1001
1002=head3 Watcher-Specific Functions and Data Members
999 1003
1000=over 4 1004=over 4
1001 1005
1002=item ev_timer_init (ev_timer *, callback, ev_tstamp after, ev_tstamp repeat) 1006=item ev_timer_init (ev_timer *, callback, ev_tstamp after, ev_tstamp repeat)
1003 1007
1109 1113
1110As with timers, the callback is guarenteed to be invoked only when the 1114As 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 1115time (C<at>) has been passed, but if multiple periodic timers become ready
1112during the same loop iteration then order of execution is undefined. 1116during the same loop iteration then order of execution is undefined.
1113 1117
1118=head3 Watcher-Specific Functions and Data Members
1119
1114=over 4 1120=over 4
1115 1121
1116=item ev_periodic_init (ev_periodic *, callback, ev_tstamp at, ev_tstamp interval, reschedule_cb) 1122=item ev_periodic_init (ev_periodic *, callback, ev_tstamp at, ev_tstamp interval, reschedule_cb)
1117 1123
1118=item ev_periodic_set (ev_periodic *, ev_tstamp after, ev_tstamp repeat, reschedule_cb) 1124=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] 1219=item ev_tstamp (*reschedule_cb)(struct ev_periodic *w, ev_tstamp now) [read-write]
1214 1220
1215The current reschedule callback, or C<0>, if this functionality is 1221The current reschedule callback, or C<0>, if this functionality is
1216switched off. Can be changed any time, but changes only take effect when 1222switched off. Can be changed any time, but changes only take effect when
1217the periodic timer fires or C<ev_periodic_again> is being called. 1223the periodic timer fires or C<ev_periodic_again> is being called.
1224
1225=item ev_tstamp at [read-only]
1226
1227When active, contains the absolute time that the watcher is supposed to
1228trigger next.
1218 1229
1219=back 1230=back
1220 1231
1221Example: Call a callback every hour, or, more precisely, whenever the 1232Example: Call a callback every hour, or, more precisely, whenever the
1222system clock is divisible by 3600. The callback invocation times have 1233system clock is divisible by 3600. The callback invocation times have
1264with the kernel (thus it coexists with your own signal handlers as long 1275with 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 1276as 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 1277watcher for a signal is stopped libev will reset the signal handler to
1267SIG_DFL (regardless of what it was set to before). 1278SIG_DFL (regardless of what it was set to before).
1268 1279
1280=head3 Watcher-Specific Functions and Data Members
1281
1269=over 4 1282=over 4
1270 1283
1271=item ev_signal_init (ev_signal *, callback, int signum) 1284=item ev_signal_init (ev_signal *, callback, int signum)
1272 1285
1273=item ev_signal_set (ev_signal *, int signum) 1286=item ev_signal_set (ev_signal *, int signum)
1284 1297
1285=head2 C<ev_child> - watch out for process status changes 1298=head2 C<ev_child> - watch out for process status changes
1286 1299
1287Child watchers trigger when your process receives a SIGCHLD in response to 1300Child watchers trigger when your process receives a SIGCHLD in response to
1288some child status changes (most typically when a child of yours dies). 1301some child status changes (most typically when a child of yours dies).
1302
1303=head3 Watcher-Specific Functions and Data Members
1289 1304
1290=over 4 1305=over 4
1291 1306
1292=item ev_child_init (ev_child *, callback, int pid) 1307=item ev_child_init (ev_child *, callback, int pid)
1293 1308
1361reader). Inotify will be used to give hints only and should not change the 1376reader). 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 1377semantics of C<ev_stat> watchers, which means that libev sometimes needs
1363to fall back to regular polling again even with inotify, but changes are 1378to fall back to regular polling again even with inotify, but changes are
1364usually detected immediately, and if the file exists there will be no 1379usually detected immediately, and if the file exists there will be no
1365polling. 1380polling.
1381
1382=head3 Watcher-Specific Functions and Data Members
1366 1383
1367=over 4 1384=over 4
1368 1385
1369=item ev_stat_init (ev_stat *, callback, const char *path, ev_tstamp interval) 1386=item ev_stat_init (ev_stat *, callback, const char *path, ev_tstamp interval)
1370 1387
1453Apart from keeping your process non-blocking (which is a useful 1470Apart from keeping your process non-blocking (which is a useful
1454effect on its own sometimes), idle watchers are a good place to do 1471effect on its own sometimes), idle watchers are a good place to do
1455"pseudo-background processing", or delay processing stuff to after the 1472"pseudo-background processing", or delay processing stuff to after the
1456event loop has handled all outstanding events. 1473event loop has handled all outstanding events.
1457 1474
1475=head3 Watcher-Specific Functions and Data Members
1476
1458=over 4 1477=over 4
1459 1478
1460=item ev_idle_init (ev_signal *, callback) 1479=item ev_idle_init (ev_signal *, callback)
1461 1480
1462Initialises and configures the idle watcher - it has no parameters of any 1481Initialises 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 1548their 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 1549loops those other event loops might be in an unusable state until their
1531C<ev_check> watcher ran (always remind yourself to coexist peacefully with 1550C<ev_check> watcher ran (always remind yourself to coexist peacefully with
1532others). 1551others).
1533 1552
1553=head3 Watcher-Specific Functions and Data Members
1554
1534=over 4 1555=over 4
1535 1556
1536=item ev_prepare_init (ev_prepare *, callback) 1557=item ev_prepare_init (ev_prepare *, callback)
1537 1558
1538=item ev_check_init (ev_check *, callback) 1559=item ev_check_init (ev_check *, callback)
1739 ev_embed_start (loop_hi, &embed); 1760 ev_embed_start (loop_hi, &embed);
1740 } 1761 }
1741 else 1762 else
1742 loop_lo = loop_hi; 1763 loop_lo = loop_hi;
1743 1764
1765=head3 Watcher-Specific Functions and Data Members
1766
1744=over 4 1767=over 4
1745 1768
1746=item ev_embed_init (ev_embed *, callback, struct ev_loop *embedded_loop) 1769=item ev_embed_init (ev_embed *, callback, struct ev_loop *embedded_loop)
1747 1770
1748=item ev_embed_set (ev_embed *, callback, struct ev_loop *embedded_loop) 1771=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, 1797event 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 1798and 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 1799C<ev_default_fork> cheats and calls it in the wrong process, the fork
1777handlers will be invoked, too, of course. 1800handlers will be invoked, too, of course.
1778 1801
1802=head3 Watcher-Specific Functions and Data Members
1803
1779=over 4 1804=over 4
1780 1805
1781=item ev_fork_init (ev_signal *, callback) 1806=item ev_fork_init (ev_signal *, callback)
1782 1807
1783Initialises and configures the fork watcher - it has no parameters of any 1808Initialises and configures the fork watcher - it has no parameters of any
1999 2024
2000=item w->stop () 2025=item w->stop ()
2001 2026
2002Stops the watcher if it is active. Again, no C<loop> argument. 2027Stops the watcher if it is active. Again, no C<loop> argument.
2003 2028
2004=item w->again () C<ev::timer>, C<ev::periodic> only 2029=item w->again () (C<ev::timer>, C<ev::periodic> only)
2005 2030
2006For C<ev::timer> and C<ev::periodic>, this invokes the corresponding 2031For C<ev::timer> and C<ev::periodic>, this invokes the corresponding
2007C<ev_TYPE_again> function. 2032C<ev_TYPE_again> function.
2008 2033
2009=item w->sweep () C<ev::embed> only 2034=item w->sweep () (C<ev::embed> only)
2010 2035
2011Invokes C<ev_embed_sweep>. 2036Invokes C<ev_embed_sweep>.
2012 2037
2013=item w->update () C<ev::stat> only 2038=item w->update () (C<ev::stat> only)
2014 2039
2015Invokes C<ev_stat_stat>. 2040Invokes C<ev_stat_stat>.
2016 2041
2017=back 2042=back
2018 2043
2038 } 2063 }
2039 2064
2040 2065
2041=head1 MACRO MAGIC 2066=head1 MACRO MAGIC
2042 2067
2043Libev can be compiled with a variety of options, the most fundemantal is 2068Libev can be compiled with a variety of options, the most fundamantal
2044C<EV_MULTIPLICITY>. This option determines whether (most) functions and 2069of which is C<EV_MULTIPLICITY>. This option determines whether (most)
2045callbacks have an initial C<struct ev_loop *> argument. 2070functions and callbacks have an initial C<struct ev_loop *> argument.
2046 2071
2047To make it easier to write programs that cope with either variant, the 2072To make it easier to write programs that cope with either variant, the
2048following macros are defined: 2073following macros are defined:
2049 2074
2050=over 4 2075=over 4

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