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Comparing libev/ev.pod (file contents):
Revision 1.191 by root, Tue Sep 30 19:45:23 2008 UTC vs.
Revision 1.197 by root, Tue Oct 21 20:52:30 2008 UTC

685C<EVUNLOOP_ONE>, which will make the innermost C<ev_loop> call return, or 685C<EVUNLOOP_ONE>, which will make the innermost C<ev_loop> call return, or
686C<EVUNLOOP_ALL>, which will make all nested C<ev_loop> calls return. 686C<EVUNLOOP_ALL>, which will make all nested C<ev_loop> calls return.
687 687
688This "unloop state" will be cleared when entering C<ev_loop> again. 688This "unloop state" will be cleared when entering C<ev_loop> again.
689 689
690It is safe to call C<ev_unloop> from otuside any C<ev_loop> calls.
691
690=item ev_ref (loop) 692=item ev_ref (loop)
691 693
692=item ev_unref (loop) 694=item ev_unref (loop)
693 695
694Ref/unref can be used to add or remove a reference count on the event 696Ref/unref can be used to add or remove a reference count on the event
892=item C<EV_ERROR> 894=item C<EV_ERROR>
893 895
894An unspecified error has occurred, the watcher has been stopped. This might 896An unspecified error has occurred, the watcher has been stopped. This might
895happen because the watcher could not be properly started because libev 897happen because the watcher could not be properly started because libev
896ran out of memory, a file descriptor was found to be closed or any other 898ran out of memory, a file descriptor was found to be closed or any other
899problem. Libev considers these application bugs.
900
897problem. You best act on it by reporting the problem and somehow coping 901You best act on it by reporting the problem and somehow coping with the
898with the watcher being stopped. 902watcher being stopped. Note that well-written programs should not receive
903an error ever, so when your watcher receives it, this usually indicates a
904bug in your program.
899 905
900Libev will usually signal a few "dummy" events together with an error, for 906Libev will usually signal a few "dummy" events together with an error, for
901example it might indicate that a fd is readable or writable, and if your 907example it might indicate that a fd is readable or writable, and if your
902callbacks is well-written it can just attempt the operation and cope with 908callbacks is well-written it can just attempt the operation and cope with
903the error from read() or write(). This will not work in multi-threaded 909the error from read() or write(). This will not work in multi-threaded
967 973
968 ev_io_start (EV_DEFAULT_UC, &w); 974 ev_io_start (EV_DEFAULT_UC, &w);
969 975
970=item C<ev_TYPE_stop> (loop *, ev_TYPE *watcher) 976=item C<ev_TYPE_stop> (loop *, ev_TYPE *watcher)
971 977
972Stops the given watcher again (if active) and clears the pending 978Stops the given watcher if active, and clears the pending status (whether
979the watcher was active or not).
980
973status. It is possible that stopped watchers are pending (for example, 981It is possible that stopped watchers are pending - for example,
974non-repeating timers are being stopped when they become pending), but 982non-repeating timers are being stopped when they become pending - but
975C<ev_TYPE_stop> ensures that the watcher is neither active nor pending. If 983calling C<ev_TYPE_stop> ensures that the watcher is neither active nor
976you want to free or reuse the memory used by the watcher it is therefore a 984pending. If you want to free or reuse the memory used by the watcher it is
977good idea to always call its C<ev_TYPE_stop> function. 985therefore a good idea to always call its C<ev_TYPE_stop> function.
978 986
979=item bool ev_is_active (ev_TYPE *watcher) 987=item bool ev_is_active (ev_TYPE *watcher)
980 988
981Returns a true value iff the watcher is active (i.e. it has been started 989Returns a true value iff the watcher is active (i.e. it has been started
982and not yet been stopped). As long as a watcher is active you must not modify 990and not yet been stopped). As long as a watcher is active you must not modify
1792to exchange stat structures with application programs compiled using the 1800to exchange stat structures with application programs compiled using the
1793default compilation environment. 1801default compilation environment.
1794 1802
1795=head3 Inotify and Kqueue 1803=head3 Inotify and Kqueue
1796 1804
1797When C<inotify (7)> support has been compiled into libev (generally only 1805When C<inotify (7)> support has been compiled into libev (generally
1806only available with Linux 2.6.25 or above due to bugs in earlier
1798available with Linux) and present at runtime, it will be used to speed up 1807implementations) and present at runtime, it will be used to speed up
1799change detection where possible. The inotify descriptor will be created lazily 1808change detection where possible. The inotify descriptor will be created
1800when the first C<ev_stat> watcher is being started. 1809lazily when the first C<ev_stat> watcher is being started.
1801 1810
1802Inotify presence does not change the semantics of C<ev_stat> watchers 1811Inotify presence does not change the semantics of C<ev_stat> watchers
1803except that changes might be detected earlier, and in some cases, to avoid 1812except that changes might be detected earlier, and in some cases, to avoid
1804making regular C<stat> calls. Even in the presence of inotify support 1813making regular C<stat> calls. Even in the presence of inotify support
1805there are many cases where libev has to resort to regular C<stat> polling, 1814there are many cases where libev has to resort to regular C<stat> polling,
2502=over 4 2511=over 4
2503 2512
2504=item ev_once (loop, int fd, int events, ev_tstamp timeout, callback) 2513=item ev_once (loop, int fd, int events, ev_tstamp timeout, callback)
2505 2514
2506This function combines a simple timer and an I/O watcher, calls your 2515This function combines a simple timer and an I/O watcher, calls your
2507callback on whichever event happens first and automatically stop both 2516callback on whichever event happens first and automatically stops both
2508watchers. This is useful if you want to wait for a single event on an fd 2517watchers. This is useful if you want to wait for a single event on an fd
2509or timeout without having to allocate/configure/start/stop/free one or 2518or timeout without having to allocate/configure/start/stop/free one or
2510more watchers yourself. 2519more watchers yourself.
2511 2520
2512If C<fd> is less than 0, then no I/O watcher will be started and events 2521If C<fd> is less than 0, then no I/O watcher will be started and the
2513is being ignored. Otherwise, an C<ev_io> watcher for the given C<fd> and 2522C<events> argument is being ignored. Otherwise, an C<ev_io> watcher for
2514C<events> set will be created and started. 2523the given C<fd> and C<events> set will be created and started.
2515 2524
2516If C<timeout> is less than 0, then no timeout watcher will be 2525If C<timeout> is less than 0, then no timeout watcher will be
2517started. Otherwise an C<ev_timer> watcher with after = C<timeout> (and 2526started. Otherwise an C<ev_timer> watcher with after = C<timeout> (and
2518repeat = 0) will be started. While C<0> is a valid timeout, it is of 2527repeat = 0) will be started. C<0> is a valid timeout.
2519dubious value.
2520 2528
2521The callback has the type C<void (*cb)(int revents, void *arg)> and gets 2529The callback has the type C<void (*cb)(int revents, void *arg)> and gets
2522passed an C<revents> set like normal event callbacks (a combination of 2530passed an C<revents> set like normal event callbacks (a combination of
2523C<EV_ERROR>, C<EV_READ>, C<EV_WRITE> or C<EV_TIMEOUT>) and the C<arg> 2531C<EV_ERROR>, C<EV_READ>, C<EV_WRITE> or C<EV_TIMEOUT>) and the C<arg>
2524value passed to C<ev_once>: 2532value passed to C<ev_once>. Note that it is possible to receive I<both>
2533a timeout and an io event at the same time - you probably should give io
2534events precedence.
2535
2536Example: wait up to ten seconds for data to appear on STDIN_FILENO.
2525 2537
2526 static void stdin_ready (int revents, void *arg) 2538 static void stdin_ready (int revents, void *arg)
2527 { 2539 {
2540 if (revents & EV_READ)
2541 /* stdin might have data for us, joy! */;
2528 if (revents & EV_TIMEOUT) 2542 else if (revents & EV_TIMEOUT)
2529 /* doh, nothing entered */; 2543 /* doh, nothing entered */;
2530 else if (revents & EV_READ)
2531 /* stdin might have data for us, joy! */;
2532 } 2544 }
2533 2545
2534 ev_once (STDIN_FILENO, EV_READ, 10., stdin_ready, 0); 2546 ev_once (STDIN_FILENO, EV_READ, 10., stdin_ready, 0);
2535 2547
2536=item ev_feed_event (ev_loop *, watcher *, int revents) 2548=item ev_feed_event (ev_loop *, watcher *, int revents)

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