ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/libev/ev.pod
(Generate patch)

Comparing libev/ev.pod (file contents):
Revision 1.388 by root, Tue Dec 20 04:08:35 2011 UTC vs.
Revision 1.397 by root, Mon Feb 13 01:52:14 2012 UTC

1878 // timeout occurred, take action 1878 // timeout occurred, take action
1879 } 1879 }
1880 else 1880 else
1881 { 1881 {
1882 // callback was invoked, but there was some recent 1882 // callback was invoked, but there was some recent
1883 // activity. simply restart the timer to time out 1883 // activity. simply restart the timer to time out
1884 // after "after" seconds, which is the earliest time 1884 // after "after" seconds, which is the earliest time
1885 // the timeout can occur. 1885 // the timeout can occur.
1886 ev_timer_set (w, after, 0.); 1886 ev_timer_set (w, after, 0.);
1887 ev_timer_start (EV_A_ w); 1887 ev_timer_start (EV_A_ w);
1888 } 1888 }
2108keep up with the timer (because it takes longer than those 10 seconds to 2108keep up with the timer (because it takes longer than those 10 seconds to
2109do stuff) the timer will not fire more than once per event loop iteration. 2109do stuff) the timer will not fire more than once per event loop iteration.
2110 2110
2111=item ev_timer_again (loop, ev_timer *) 2111=item ev_timer_again (loop, ev_timer *)
2112 2112
2113This will act as if the timer timed out and restarts it again if it is 2113This will act as if the timer timed out, and restarts it again if it is
2114repeating. The exact semantics are: 2114repeating. It basically works like calling C<ev_timer_stop>, updating the
2115timeout to the C<repeat> value and calling C<ev_timer_start>.
2115 2116
2117The exact semantics are as in the following rules, all of which will be
2118applied to the watcher:
2119
2120=over 4
2121
2116If the timer is pending, its pending status is cleared. 2122=item If the timer is pending, the pending status is always cleared.
2117 2123
2118If the timer is started but non-repeating, stop it (as if it timed out). 2124=item If the timer is started but non-repeating, stop it (as if it timed
2125out, without invoking it).
2119 2126
2120If the timer is repeating, either start it if necessary (with the 2127=item If the timer is repeating, make the C<repeat> value the new timeout
2121C<repeat> value), or reset the running timer to the C<repeat> value. 2128and start the timer, if necessary.
2129
2130=back
2122 2131
2123This sounds a bit complicated, see L<Be smart about timeouts>, above, for a 2132This sounds a bit complicated, see L<Be smart about timeouts>, above, for a
2124usage example. 2133usage example.
2125 2134
2126=item ev_tstamp ev_timer_remaining (loop, ev_timer *) 2135=item ev_tstamp ev_timer_remaining (loop, ev_timer *)
3633 int exit_main_loop = 0; 3642 int exit_main_loop = 0;
3634 3643
3635 while (!exit_main_loop) 3644 while (!exit_main_loop)
3636 ev_run (EV_DEFAULT_ EVRUN_ONCE); 3645 ev_run (EV_DEFAULT_ EVRUN_ONCE);
3637 3646
3638 // in a model watcher 3647 // in a modal watcher
3639 int exit_nested_loop = 0; 3648 int exit_nested_loop = 0;
3640 3649
3641 while (!exit_nested_loop) 3650 while (!exit_nested_loop)
3642 ev_run (EV_A_ EVRUN_ONCE); 3651 ev_run (EV_A_ EVRUN_ONCE);
3643 3652
3823 switch_to (libev_coro); 3832 switch_to (libev_coro);
3824 } 3833 }
3825 3834
3826That basically suspends the coroutine inside C<wait_for_event> and 3835That basically suspends the coroutine inside C<wait_for_event> and
3827continues the libev coroutine, which, when appropriate, switches back to 3836continues the libev coroutine, which, when appropriate, switches back to
3828this or any other coroutine. I am sure if you sue this your own :) 3837this or any other coroutine.
3829 3838
3830You can do similar tricks if you have, say, threads with an event queue - 3839You can do similar tricks if you have, say, threads with an event queue -
3831instead of storing a coroutine, you store the queue object and instead of 3840instead of storing a coroutine, you store the queue object and instead of
3832switching to a coroutine, you push the watcher onto the queue and notify 3841switching to a coroutine, you push the watcher onto the queue and notify
3833any waiters. 3842any waiters.
3908with C<operator ()> can be used as callbacks. Other types should be easy 3917with C<operator ()> can be used as callbacks. Other types should be easy
3909to add as long as they only need one additional pointer for context. If 3918to add as long as they only need one additional pointer for context. If
3910you need support for other types of functors please contact the author 3919you need support for other types of functors please contact the author
3911(preferably after implementing it). 3920(preferably after implementing it).
3912 3921
3922For all this to work, your C++ compiler either has to use the same calling
3923conventions as your C compiler (for static member functions), or you have
3924to embed libev and compile libev itself as C++.
3925
3913Here is a list of things available in the C<ev> namespace: 3926Here is a list of things available in the C<ev> namespace:
3914 3927
3915=over 4 3928=over 4
3916 3929
3917=item C<ev::READ>, C<ev::WRITE> etc. 3930=item C<ev::READ>, C<ev::WRITE> etc.
3926=item C<ev::io>, C<ev::timer>, C<ev::periodic>, C<ev::idle>, C<ev::sig> etc. 3939=item C<ev::io>, C<ev::timer>, C<ev::periodic>, C<ev::idle>, C<ev::sig> etc.
3927 3940
3928For each C<ev_TYPE> watcher in F<ev.h> there is a corresponding class of 3941For each C<ev_TYPE> watcher in F<ev.h> there is a corresponding class of
3929the same name in the C<ev> namespace, with the exception of C<ev_signal> 3942the same name in the C<ev> namespace, with the exception of C<ev_signal>
3930which is called C<ev::sig> to avoid clashes with the C<signal> macro 3943which is called C<ev::sig> to avoid clashes with the C<signal> macro
3931defines by many implementations. 3944defined by many implementations.
3932 3945
3933All of those classes have these methods: 3946All of those classes have these methods:
3934 3947
3935=over 4 3948=over 4
3936 3949
4495If defined to be C<1>, libev will compile in support for the Linux inotify 4508If defined to be C<1>, libev will compile in support for the Linux inotify
4496interface to speed up C<ev_stat> watchers. Its actual availability will 4509interface to speed up C<ev_stat> watchers. Its actual availability will
4497be detected at runtime. If undefined, it will be enabled if the headers 4510be detected at runtime. If undefined, it will be enabled if the headers
4498indicate GNU/Linux + Glibc 2.4 or newer, otherwise disabled. 4511indicate GNU/Linux + Glibc 2.4 or newer, otherwise disabled.
4499 4512
4513=item EV_NO_SMP
4514
4515If defined to be C<1>, libev will assume that memory is always coherent
4516between threads, that is, threads can be used, but threads never run on
4517different cpus (or different cpu cores). This reduces dependencies
4518and makes libev faster.
4519
4520=item EV_NO_THREADS
4521
4522If defined to be C<1>, libev will assume that it will never be called
4523from different threads, which is a stronger assumption than C<EV_NO_SMP>,
4524above. This reduces dependencies and makes libev faster.
4525
4500=item EV_ATOMIC_T 4526=item EV_ATOMIC_T
4501 4527
4502Libev requires an integer type (suitable for storing C<0> or C<1>) whose 4528Libev requires an integer type (suitable for storing C<0> or C<1>) whose
4503access is atomic and serialised with respect to other threads or signal 4529access is atomic and serialised with respect to other threads or signal
4504contexts. No such type is easily found in the C language, so you can 4530contexts. No such type is easily found in the C language, so you can
4662when you embed libev, only want to use libev functions in a single file, 4688when you embed libev, only want to use libev functions in a single file,
4663and do not want its identifiers to be visible. 4689and do not want its identifiers to be visible.
4664 4690
4665To use this, define C<EV_API_STATIC> and include F<ev.c> in the file that 4691To use this, define C<EV_API_STATIC> and include F<ev.c> in the file that
4666wants to use libev. 4692wants to use libev.
4693
4694This option only works when libev is compiled with a C compiler, as C++
4695doesn't support the required declaration syntax.
4667 4696
4668=item EV_AVOID_STDIO 4697=item EV_AVOID_STDIO
4669 4698
4670If this is set to C<1> at compiletime, then libev will avoid using stdio 4699If this is set to C<1> at compiletime, then libev will avoid using stdio
4671functions (printf, scanf, perror etc.). This will increase the code size 4700functions (printf, scanf, perror etc.). This will increase the code size

Diff Legend

Removed lines
+ Added lines
< Changed lines
> Changed lines