… | |
… | |
10 | |
10 | |
11 | // a single header file is required |
11 | // a single header file is required |
12 | #include <ev.h> |
12 | #include <ev.h> |
13 | |
13 | |
14 | // every watcher type has its own typedef'd struct |
14 | // every watcher type has its own typedef'd struct |
15 | // with the name ev_<type> |
15 | // with the name ev_TYPE |
16 | ev_io stdin_watcher; |
16 | ev_io stdin_watcher; |
17 | ev_timer timeout_watcher; |
17 | ev_timer timeout_watcher; |
18 | |
18 | |
19 | // all watcher callbacks have a similar signature |
19 | // all watcher callbacks have a similar signature |
20 | // this callback is called when data is readable on stdin |
20 | // this callback is called when data is readable on stdin |
21 | static void |
21 | static void |
22 | stdin_cb (EV_P_ struct ev_io *w, int revents) |
22 | stdin_cb (EV_P_ ev_io *w, int revents) |
23 | { |
23 | { |
24 | puts ("stdin ready"); |
24 | puts ("stdin ready"); |
25 | // for one-shot events, one must manually stop the watcher |
25 | // for one-shot events, one must manually stop the watcher |
26 | // with its corresponding stop function. |
26 | // with its corresponding stop function. |
27 | ev_io_stop (EV_A_ w); |
27 | ev_io_stop (EV_A_ w); |
… | |
… | |
30 | ev_unloop (EV_A_ EVUNLOOP_ALL); |
30 | ev_unloop (EV_A_ EVUNLOOP_ALL); |
31 | } |
31 | } |
32 | |
32 | |
33 | // another callback, this time for a time-out |
33 | // another callback, this time for a time-out |
34 | static void |
34 | static void |
35 | timeout_cb (EV_P_ struct ev_timer *w, int revents) |
35 | timeout_cb (EV_P_ ev_timer *w, int revents) |
36 | { |
36 | { |
37 | puts ("timeout"); |
37 | puts ("timeout"); |
38 | // this causes the innermost ev_loop to stop iterating |
38 | // this causes the innermost ev_loop to stop iterating |
39 | ev_unloop (EV_A_ EVUNLOOP_ONE); |
39 | ev_unloop (EV_A_ EVUNLOOP_ONE); |
40 | } |
40 | } |
41 | |
41 | |
42 | int |
42 | int |
43 | main (void) |
43 | main (void) |
44 | { |
44 | { |
45 | // use the default event loop unless you have special needs |
45 | // use the default event loop unless you have special needs |
46 | struct ev_loop *loop = ev_default_loop (0); |
46 | ev_loop *loop = ev_default_loop (0); |
47 | |
47 | |
48 | // initialise an io watcher, then start it |
48 | // initialise an io watcher, then start it |
49 | // this one will watch for stdin to become readable |
49 | // this one will watch for stdin to become readable |
50 | ev_io_init (&stdin_watcher, stdin_cb, /*STDIN_FILENO*/ 0, EV_READ); |
50 | ev_io_init (&stdin_watcher, stdin_cb, /*STDIN_FILENO*/ 0, EV_READ); |
51 | ev_io_start (loop, &stdin_watcher); |
51 | ev_io_start (loop, &stdin_watcher); |
… | |
… | |
103 | Libev is very configurable. In this manual the default (and most common) |
103 | Libev is very configurable. In this manual the default (and most common) |
104 | configuration will be described, which supports multiple event loops. For |
104 | configuration will be described, which supports multiple event loops. For |
105 | more info about various configuration options please have a look at |
105 | more info about various configuration options please have a look at |
106 | B<EMBED> section in this manual. If libev was configured without support |
106 | B<EMBED> section in this manual. If libev was configured without support |
107 | for multiple event loops, then all functions taking an initial argument of |
107 | for multiple event loops, then all functions taking an initial argument of |
108 | name C<loop> (which is always of type C<struct ev_loop *>) will not have |
108 | name C<loop> (which is always of type C<ev_loop *>) will not have |
109 | this argument. |
109 | this argument. |
110 | |
110 | |
111 | =head2 TIME REPRESENTATION |
111 | =head2 TIME REPRESENTATION |
112 | |
112 | |
113 | Libev represents time as a single floating point number, representing the |
113 | Libev represents time as a single floating point number, representing the |
… | |
… | |
276 | |
276 | |
277 | =back |
277 | =back |
278 | |
278 | |
279 | =head1 FUNCTIONS CONTROLLING THE EVENT LOOP |
279 | =head1 FUNCTIONS CONTROLLING THE EVENT LOOP |
280 | |
280 | |
281 | An event loop is described by a C<struct ev_loop *>. The library knows two |
281 | An event loop is described by a C<struct ev_loop *> (the C<struct> |
282 | types of such loops, the I<default> loop, which supports signals and child |
282 | is I<not> optional in this case, as there is also an C<ev_loop> |
283 | events, and dynamically created loops which do not. |
283 | I<function>). |
|
|
284 | |
|
|
285 | The library knows two types of such loops, the I<default> loop, which |
|
|
286 | supports signals and child events, and dynamically created loops which do |
|
|
287 | not. |
284 | |
288 | |
285 | =over 4 |
289 | =over 4 |
286 | |
290 | |
287 | =item struct ev_loop *ev_default_loop (unsigned int flags) |
291 | =item struct ev_loop *ev_default_loop (unsigned int flags) |
288 | |
292 | |
… | |
… | |
710 | respectively). |
714 | respectively). |
711 | |
715 | |
712 | Example: Create a signal watcher, but keep it from keeping C<ev_loop> |
716 | Example: Create a signal watcher, but keep it from keeping C<ev_loop> |
713 | running when nothing else is active. |
717 | running when nothing else is active. |
714 | |
718 | |
715 | struct ev_signal exitsig; |
719 | ev_signal exitsig; |
716 | ev_signal_init (&exitsig, sig_cb, SIGINT); |
720 | ev_signal_init (&exitsig, sig_cb, SIGINT); |
717 | ev_signal_start (loop, &exitsig); |
721 | ev_signal_start (loop, &exitsig); |
718 | evf_unref (loop); |
722 | evf_unref (loop); |
719 | |
723 | |
720 | Example: For some weird reason, unregister the above signal handler again. |
724 | Example: For some weird reason, unregister the above signal handler again. |
… | |
… | |
768 | they fire on, say, one-second boundaries only. |
772 | they fire on, say, one-second boundaries only. |
769 | |
773 | |
770 | =item ev_loop_verify (loop) |
774 | =item ev_loop_verify (loop) |
771 | |
775 | |
772 | This function only does something when C<EV_VERIFY> support has been |
776 | This function only does something when C<EV_VERIFY> support has been |
773 | compiled in. which is the default for non-minimal builds. It tries to go |
777 | compiled in, which is the default for non-minimal builds. It tries to go |
774 | through all internal structures and checks them for validity. If anything |
778 | through all internal structures and checks them for validity. If anything |
775 | is found to be inconsistent, it will print an error message to standard |
779 | is found to be inconsistent, it will print an error message to standard |
776 | error and call C<abort ()>. |
780 | error and call C<abort ()>. |
777 | |
781 | |
778 | This can be used to catch bugs inside libev itself: under normal |
782 | This can be used to catch bugs inside libev itself: under normal |
… | |
… | |
782 | =back |
786 | =back |
783 | |
787 | |
784 | |
788 | |
785 | =head1 ANATOMY OF A WATCHER |
789 | =head1 ANATOMY OF A WATCHER |
786 | |
790 | |
|
|
791 | In the following description, uppercase C<TYPE> in names stands for the |
|
|
792 | watcher type, e.g. C<ev_TYPE_start> can mean C<ev_timer_start> for timer |
|
|
793 | watchers and C<ev_io_start> for I/O watchers. |
|
|
794 | |
787 | A watcher is a structure that you create and register to record your |
795 | A watcher is a structure that you create and register to record your |
788 | interest in some event. For instance, if you want to wait for STDIN to |
796 | interest in some event. For instance, if you want to wait for STDIN to |
789 | become readable, you would create an C<ev_io> watcher for that: |
797 | become readable, you would create an C<ev_io> watcher for that: |
790 | |
798 | |
791 | static void my_cb (struct ev_loop *loop, struct ev_io *w, int revents) |
799 | static void my_cb (struct ev_loop *loop, ev_io *w, int revents) |
792 | { |
800 | { |
793 | ev_io_stop (w); |
801 | ev_io_stop (w); |
794 | ev_unloop (loop, EVUNLOOP_ALL); |
802 | ev_unloop (loop, EVUNLOOP_ALL); |
795 | } |
803 | } |
796 | |
804 | |
797 | struct ev_loop *loop = ev_default_loop (0); |
805 | struct ev_loop *loop = ev_default_loop (0); |
|
|
806 | |
798 | struct ev_io stdin_watcher; |
807 | ev_io stdin_watcher; |
|
|
808 | |
799 | ev_init (&stdin_watcher, my_cb); |
809 | ev_init (&stdin_watcher, my_cb); |
800 | ev_io_set (&stdin_watcher, STDIN_FILENO, EV_READ); |
810 | ev_io_set (&stdin_watcher, STDIN_FILENO, EV_READ); |
801 | ev_io_start (loop, &stdin_watcher); |
811 | ev_io_start (loop, &stdin_watcher); |
|
|
812 | |
802 | ev_loop (loop, 0); |
813 | ev_loop (loop, 0); |
803 | |
814 | |
804 | As you can see, you are responsible for allocating the memory for your |
815 | As you can see, you are responsible for allocating the memory for your |
805 | watcher structures (and it is usually a bad idea to do this on the stack, |
816 | watcher structures (and it is I<usually> a bad idea to do this on the |
806 | although this can sometimes be quite valid). |
817 | stack). |
|
|
818 | |
|
|
819 | Each watcher has an associated watcher structure (called C<struct ev_TYPE> |
|
|
820 | or simply C<ev_TYPE>, as typedefs are provided for all watcher structs). |
807 | |
821 | |
808 | Each watcher structure must be initialised by a call to C<ev_init |
822 | Each watcher structure must be initialised by a call to C<ev_init |
809 | (watcher *, callback)>, which expects a callback to be provided. This |
823 | (watcher *, callback)>, which expects a callback to be provided. This |
810 | callback gets invoked each time the event occurs (or, in the case of I/O |
824 | callback gets invoked each time the event occurs (or, in the case of I/O |
811 | watchers, each time the event loop detects that the file descriptor given |
825 | watchers, each time the event loop detects that the file descriptor given |
812 | is readable and/or writable). |
826 | is readable and/or writable). |
813 | |
827 | |
814 | Each watcher type has its own C<< ev_<type>_set (watcher *, ...) >> macro |
828 | Each watcher type further has its own C<< ev_TYPE_set (watcher *, ...) >> |
815 | with arguments specific to this watcher type. There is also a macro |
829 | macro to configure it, with arguments specific to the watcher type. There |
816 | to combine initialisation and setting in one call: C<< ev_<type>_init |
830 | is also a macro to combine initialisation and setting in one call: C<< |
817 | (watcher *, callback, ...) >>. |
831 | ev_TYPE_init (watcher *, callback, ...) >>. |
818 | |
832 | |
819 | To make the watcher actually watch out for events, you have to start it |
833 | To make the watcher actually watch out for events, you have to start it |
820 | with a watcher-specific start function (C<< ev_<type>_start (loop, watcher |
834 | with a watcher-specific start function (C<< ev_TYPE_start (loop, watcher |
821 | *) >>), and you can stop watching for events at any time by calling the |
835 | *) >>), and you can stop watching for events at any time by calling the |
822 | corresponding stop function (C<< ev_<type>_stop (loop, watcher *) >>. |
836 | corresponding stop function (C<< ev_TYPE_stop (loop, watcher *) >>. |
823 | |
837 | |
824 | As long as your watcher is active (has been started but not stopped) you |
838 | As long as your watcher is active (has been started but not stopped) you |
825 | must not touch the values stored in it. Most specifically you must never |
839 | must not touch the values stored in it. Most specifically you must never |
826 | reinitialise it or call its C<set> macro. |
840 | reinitialise it or call its C<ev_TYPE_set> macro. |
827 | |
841 | |
828 | Each and every callback receives the event loop pointer as first, the |
842 | Each and every callback receives the event loop pointer as first, the |
829 | registered watcher structure as second, and a bitset of received events as |
843 | registered watcher structure as second, and a bitset of received events as |
830 | third argument. |
844 | third argument. |
831 | |
845 | |
… | |
… | |
912 | |
926 | |
913 | =back |
927 | =back |
914 | |
928 | |
915 | =head2 GENERIC WATCHER FUNCTIONS |
929 | =head2 GENERIC WATCHER FUNCTIONS |
916 | |
930 | |
917 | In the following description, C<TYPE> stands for the watcher type, |
|
|
918 | e.g. C<timer> for C<ev_timer> watchers and C<io> for C<ev_io> watchers. |
|
|
919 | |
|
|
920 | =over 4 |
931 | =over 4 |
921 | |
932 | |
922 | =item C<ev_init> (ev_TYPE *watcher, callback) |
933 | =item C<ev_init> (ev_TYPE *watcher, callback) |
923 | |
934 | |
924 | This macro initialises the generic portion of a watcher. The contents |
935 | This macro initialises the generic portion of a watcher. The contents |
… | |
… | |
929 | which rolls both calls into one. |
940 | which rolls both calls into one. |
930 | |
941 | |
931 | You can reinitialise a watcher at any time as long as it has been stopped |
942 | You can reinitialise a watcher at any time as long as it has been stopped |
932 | (or never started) and there are no pending events outstanding. |
943 | (or never started) and there are no pending events outstanding. |
933 | |
944 | |
934 | The callback is always of type C<void (*)(ev_loop *loop, ev_TYPE *watcher, |
945 | The callback is always of type C<void (*)(struct ev_loop *loop, ev_TYPE *watcher, |
935 | int revents)>. |
946 | int revents)>. |
936 | |
947 | |
937 | Example: Initialise an C<ev_io> watcher in two steps. |
948 | Example: Initialise an C<ev_io> watcher in two steps. |
938 | |
949 | |
939 | ev_io w; |
950 | ev_io w; |
… | |
… | |
1032 | The default priority used by watchers when no priority has been set is |
1043 | The default priority used by watchers when no priority has been set is |
1033 | always C<0>, which is supposed to not be too high and not be too low :). |
1044 | always C<0>, which is supposed to not be too high and not be too low :). |
1034 | |
1045 | |
1035 | Setting a priority outside the range of C<EV_MINPRI> to C<EV_MAXPRI> is |
1046 | Setting a priority outside the range of C<EV_MINPRI> to C<EV_MAXPRI> is |
1036 | fine, as long as you do not mind that the priority value you query might |
1047 | fine, as long as you do not mind that the priority value you query might |
1037 | or might not have been adjusted to be within valid range. |
1048 | or might not have been clamped to the valid range. |
1038 | |
1049 | |
1039 | =item ev_invoke (loop, ev_TYPE *watcher, int revents) |
1050 | =item ev_invoke (loop, ev_TYPE *watcher, int revents) |
1040 | |
1051 | |
1041 | Invoke the C<watcher> with the given C<loop> and C<revents>. Neither |
1052 | Invoke the C<watcher> with the given C<loop> and C<revents>. Neither |
1042 | C<loop> nor C<revents> need to be valid as long as the watcher callback |
1053 | C<loop> nor C<revents> need to be valid as long as the watcher callback |
… | |
… | |
1064 | member, you can also "subclass" the watcher type and provide your own |
1075 | member, you can also "subclass" the watcher type and provide your own |
1065 | data: |
1076 | data: |
1066 | |
1077 | |
1067 | struct my_io |
1078 | struct my_io |
1068 | { |
1079 | { |
1069 | struct ev_io io; |
1080 | ev_io io; |
1070 | int otherfd; |
1081 | int otherfd; |
1071 | void *somedata; |
1082 | void *somedata; |
1072 | struct whatever *mostinteresting; |
1083 | struct whatever *mostinteresting; |
1073 | }; |
1084 | }; |
1074 | |
1085 | |
… | |
… | |
1077 | ev_io_init (&w.io, my_cb, fd, EV_READ); |
1088 | ev_io_init (&w.io, my_cb, fd, EV_READ); |
1078 | |
1089 | |
1079 | And since your callback will be called with a pointer to the watcher, you |
1090 | And since your callback will be called with a pointer to the watcher, you |
1080 | can cast it back to your own type: |
1091 | can cast it back to your own type: |
1081 | |
1092 | |
1082 | static void my_cb (struct ev_loop *loop, struct ev_io *w_, int revents) |
1093 | static void my_cb (struct ev_loop *loop, ev_io *w_, int revents) |
1083 | { |
1094 | { |
1084 | struct my_io *w = (struct my_io *)w_; |
1095 | struct my_io *w = (struct my_io *)w_; |
1085 | ... |
1096 | ... |
1086 | } |
1097 | } |
1087 | |
1098 | |
… | |
… | |
1105 | programmers): |
1116 | programmers): |
1106 | |
1117 | |
1107 | #include <stddef.h> |
1118 | #include <stddef.h> |
1108 | |
1119 | |
1109 | static void |
1120 | static void |
1110 | t1_cb (EV_P_ struct ev_timer *w, int revents) |
1121 | t1_cb (EV_P_ ev_timer *w, int revents) |
1111 | { |
1122 | { |
1112 | struct my_biggy big = (struct my_biggy * |
1123 | struct my_biggy big = (struct my_biggy * |
1113 | (((char *)w) - offsetof (struct my_biggy, t1)); |
1124 | (((char *)w) - offsetof (struct my_biggy, t1)); |
1114 | } |
1125 | } |
1115 | |
1126 | |
1116 | static void |
1127 | static void |
1117 | t2_cb (EV_P_ struct ev_timer *w, int revents) |
1128 | t2_cb (EV_P_ ev_timer *w, int revents) |
1118 | { |
1129 | { |
1119 | struct my_biggy big = (struct my_biggy * |
1130 | struct my_biggy big = (struct my_biggy * |
1120 | (((char *)w) - offsetof (struct my_biggy, t2)); |
1131 | (((char *)w) - offsetof (struct my_biggy, t2)); |
1121 | } |
1132 | } |
1122 | |
1133 | |
… | |
… | |
1257 | Example: Call C<stdin_readable_cb> when STDIN_FILENO has become, well |
1268 | Example: Call C<stdin_readable_cb> when STDIN_FILENO has become, well |
1258 | readable, but only once. Since it is likely line-buffered, you could |
1269 | readable, but only once. Since it is likely line-buffered, you could |
1259 | attempt to read a whole line in the callback. |
1270 | attempt to read a whole line in the callback. |
1260 | |
1271 | |
1261 | static void |
1272 | static void |
1262 | stdin_readable_cb (struct ev_loop *loop, struct ev_io *w, int revents) |
1273 | stdin_readable_cb (struct ev_loop *loop, ev_io *w, int revents) |
1263 | { |
1274 | { |
1264 | ev_io_stop (loop, w); |
1275 | ev_io_stop (loop, w); |
1265 | .. read from stdin here (or from w->fd) and handle any I/O errors |
1276 | .. read from stdin here (or from w->fd) and handle any I/O errors |
1266 | } |
1277 | } |
1267 | |
1278 | |
1268 | ... |
1279 | ... |
1269 | struct ev_loop *loop = ev_default_init (0); |
1280 | struct ev_loop *loop = ev_default_init (0); |
1270 | struct ev_io stdin_readable; |
1281 | ev_io stdin_readable; |
1271 | ev_io_init (&stdin_readable, stdin_readable_cb, STDIN_FILENO, EV_READ); |
1282 | ev_io_init (&stdin_readable, stdin_readable_cb, STDIN_FILENO, EV_READ); |
1272 | ev_io_start (loop, &stdin_readable); |
1283 | ev_io_start (loop, &stdin_readable); |
1273 | ev_loop (loop, 0); |
1284 | ev_loop (loop, 0); |
1274 | |
1285 | |
1275 | |
1286 | |
… | |
… | |
1286 | |
1297 | |
1287 | The callback is guaranteed to be invoked only I<after> its timeout has |
1298 | The callback is guaranteed to be invoked only I<after> its timeout has |
1288 | passed, but if multiple timers become ready during the same loop iteration |
1299 | passed, but if multiple timers become ready during the same loop iteration |
1289 | then order of execution is undefined. |
1300 | then order of execution is undefined. |
1290 | |
1301 | |
|
|
1302 | =head3 Be smart about timeouts |
|
|
1303 | |
|
|
1304 | Many real-world problems involve some kind of timeout, usually for error |
|
|
1305 | recovery. A typical example is an HTTP request - if the other side hangs, |
|
|
1306 | you want to raise some error after a while. |
|
|
1307 | |
|
|
1308 | What follows are some ways to handle this problem, from obvious and |
|
|
1309 | inefficient to smart and efficient. |
|
|
1310 | |
|
|
1311 | In the following, a 60 second activity timeout is assumed - a timeout that |
|
|
1312 | gets reset to 60 seconds each time there is activity (e.g. each time some |
|
|
1313 | data or other life sign was received). |
|
|
1314 | |
|
|
1315 | =over 4 |
|
|
1316 | |
|
|
1317 | =item 1. Use a timer and stop, reinitialise and start it on activity. |
|
|
1318 | |
|
|
1319 | This is the most obvious, but not the most simple way: In the beginning, |
|
|
1320 | start the watcher: |
|
|
1321 | |
|
|
1322 | ev_timer_init (timer, callback, 60., 0.); |
|
|
1323 | ev_timer_start (loop, timer); |
|
|
1324 | |
|
|
1325 | Then, each time there is some activity, C<ev_timer_stop> it, initialise it |
|
|
1326 | and start it again: |
|
|
1327 | |
|
|
1328 | ev_timer_stop (loop, timer); |
|
|
1329 | ev_timer_set (timer, 60., 0.); |
|
|
1330 | ev_timer_start (loop, timer); |
|
|
1331 | |
|
|
1332 | This is relatively simple to implement, but means that each time there is |
|
|
1333 | some activity, libev will first have to remove the timer from its internal |
|
|
1334 | data structure and then add it again. Libev tries to be fast, but it's |
|
|
1335 | still not a constant-time operation. |
|
|
1336 | |
|
|
1337 | =item 2. Use a timer and re-start it with C<ev_timer_again> inactivity. |
|
|
1338 | |
|
|
1339 | This is the easiest way, and involves using C<ev_timer_again> instead of |
|
|
1340 | C<ev_timer_start>. |
|
|
1341 | |
|
|
1342 | To implement this, configure an C<ev_timer> with a C<repeat> value |
|
|
1343 | of C<60> and then call C<ev_timer_again> at start and each time you |
|
|
1344 | successfully read or write some data. If you go into an idle state where |
|
|
1345 | you do not expect data to travel on the socket, you can C<ev_timer_stop> |
|
|
1346 | the timer, and C<ev_timer_again> will automatically restart it if need be. |
|
|
1347 | |
|
|
1348 | That means you can ignore both the C<ev_timer_start> function and the |
|
|
1349 | C<after> argument to C<ev_timer_set>, and only ever use the C<repeat> |
|
|
1350 | member and C<ev_timer_again>. |
|
|
1351 | |
|
|
1352 | At start: |
|
|
1353 | |
|
|
1354 | ev_timer_init (timer, callback); |
|
|
1355 | timer->repeat = 60.; |
|
|
1356 | ev_timer_again (loop, timer); |
|
|
1357 | |
|
|
1358 | Each time there is some activity: |
|
|
1359 | |
|
|
1360 | ev_timer_again (loop, timer); |
|
|
1361 | |
|
|
1362 | It is even possible to change the time-out on the fly, regardless of |
|
|
1363 | whether the watcher is active or not: |
|
|
1364 | |
|
|
1365 | timer->repeat = 30.; |
|
|
1366 | ev_timer_again (loop, timer); |
|
|
1367 | |
|
|
1368 | This is slightly more efficient then stopping/starting the timer each time |
|
|
1369 | you want to modify its timeout value, as libev does not have to completely |
|
|
1370 | remove and re-insert the timer from/into its internal data structure. |
|
|
1371 | |
|
|
1372 | It is, however, even simpler than the "obvious" way to do it. |
|
|
1373 | |
|
|
1374 | =item 3. Let the timer time out, but then re-arm it as required. |
|
|
1375 | |
|
|
1376 | This method is more tricky, but usually most efficient: Most timeouts are |
|
|
1377 | relatively long compared to the intervals between other activity - in |
|
|
1378 | our example, within 60 seconds, there are usually many I/O events with |
|
|
1379 | associated activity resets. |
|
|
1380 | |
|
|
1381 | In this case, it would be more efficient to leave the C<ev_timer> alone, |
|
|
1382 | but remember the time of last activity, and check for a real timeout only |
|
|
1383 | within the callback: |
|
|
1384 | |
|
|
1385 | ev_tstamp last_activity; // time of last activity |
|
|
1386 | |
|
|
1387 | static void |
|
|
1388 | callback (EV_P_ ev_timer *w, int revents) |
|
|
1389 | { |
|
|
1390 | ev_tstamp now = ev_now (EV_A); |
|
|
1391 | ev_tstamp timeout = last_activity + 60.; |
|
|
1392 | |
|
|
1393 | // if last_activity + 60. is older than now, we did time out |
|
|
1394 | if (timeout < now) |
|
|
1395 | { |
|
|
1396 | // timeout occured, take action |
|
|
1397 | } |
|
|
1398 | else |
|
|
1399 | { |
|
|
1400 | // callback was invoked, but there was some activity, re-arm |
|
|
1401 | // the watcher to fire in last_activity + 60, which is |
|
|
1402 | // guaranteed to be in the future, so "again" is positive: |
|
|
1403 | w->again = timeout - now; |
|
|
1404 | ev_timer_again (EV_A_ w); |
|
|
1405 | } |
|
|
1406 | } |
|
|
1407 | |
|
|
1408 | To summarise the callback: first calculate the real timeout (defined |
|
|
1409 | as "60 seconds after the last activity"), then check if that time has |
|
|
1410 | been reached, which means something I<did>, in fact, time out. Otherwise |
|
|
1411 | the callback was invoked too early (C<timeout> is in the future), so |
|
|
1412 | re-schedule the timer to fire at that future time, to see if maybe we have |
|
|
1413 | a timeout then. |
|
|
1414 | |
|
|
1415 | Note how C<ev_timer_again> is used, taking advantage of the |
|
|
1416 | C<ev_timer_again> optimisation when the timer is already running. |
|
|
1417 | |
|
|
1418 | This scheme causes more callback invocations (about one every 60 seconds |
|
|
1419 | minus half the average time between activity), but virtually no calls to |
|
|
1420 | libev to change the timeout. |
|
|
1421 | |
|
|
1422 | To start the timer, simply initialise the watcher and set C<last_activity> |
|
|
1423 | to the current time (meaning we just have some activity :), then call the |
|
|
1424 | callback, which will "do the right thing" and start the timer: |
|
|
1425 | |
|
|
1426 | ev_timer_init (timer, callback); |
|
|
1427 | last_activity = ev_now (loop); |
|
|
1428 | callback (loop, timer, EV_TIMEOUT); |
|
|
1429 | |
|
|
1430 | And when there is some activity, simply store the current time in |
|
|
1431 | C<last_activity>, no libev calls at all: |
|
|
1432 | |
|
|
1433 | last_actiivty = ev_now (loop); |
|
|
1434 | |
|
|
1435 | This technique is slightly more complex, but in most cases where the |
|
|
1436 | time-out is unlikely to be triggered, much more efficient. |
|
|
1437 | |
|
|
1438 | Changing the timeout is trivial as well (if it isn't hard-coded in the |
|
|
1439 | callback :) - just change the timeout and invoke the callback, which will |
|
|
1440 | fix things for you. |
|
|
1441 | |
|
|
1442 | =item 4. Wee, just use a double-linked list for your timeouts. |
|
|
1443 | |
|
|
1444 | If there is not one request, but many thousands (millions...), all |
|
|
1445 | employing some kind of timeout with the same timeout value, then one can |
|
|
1446 | do even better: |
|
|
1447 | |
|
|
1448 | When starting the timeout, calculate the timeout value and put the timeout |
|
|
1449 | at the I<end> of the list. |
|
|
1450 | |
|
|
1451 | Then use an C<ev_timer> to fire when the timeout at the I<beginning> of |
|
|
1452 | the list is expected to fire (for example, using the technique #3). |
|
|
1453 | |
|
|
1454 | When there is some activity, remove the timer from the list, recalculate |
|
|
1455 | the timeout, append it to the end of the list again, and make sure to |
|
|
1456 | update the C<ev_timer> if it was taken from the beginning of the list. |
|
|
1457 | |
|
|
1458 | This way, one can manage an unlimited number of timeouts in O(1) time for |
|
|
1459 | starting, stopping and updating the timers, at the expense of a major |
|
|
1460 | complication, and having to use a constant timeout. The constant timeout |
|
|
1461 | ensures that the list stays sorted. |
|
|
1462 | |
|
|
1463 | =back |
|
|
1464 | |
|
|
1465 | So which method the best? |
|
|
1466 | |
|
|
1467 | Method #2 is a simple no-brain-required solution that is adequate in most |
|
|
1468 | situations. Method #3 requires a bit more thinking, but handles many cases |
|
|
1469 | better, and isn't very complicated either. In most case, choosing either |
|
|
1470 | one is fine, with #3 being better in typical situations. |
|
|
1471 | |
|
|
1472 | Method #1 is almost always a bad idea, and buys you nothing. Method #4 is |
|
|
1473 | rather complicated, but extremely efficient, something that really pays |
|
|
1474 | off after the first million or so of active timers, i.e. it's usually |
|
|
1475 | overkill :) |
|
|
1476 | |
1291 | =head3 The special problem of time updates |
1477 | =head3 The special problem of time updates |
1292 | |
1478 | |
1293 | Establishing the current time is a costly operation (it usually takes at |
1479 | Establishing the current time is a costly operation (it usually takes at |
1294 | least two system calls): EV therefore updates its idea of the current |
1480 | least two system calls): EV therefore updates its idea of the current |
1295 | time only before and after C<ev_loop> collects new events, which causes a |
1481 | time only before and after C<ev_loop> collects new events, which causes a |
… | |
… | |
1338 | If the timer is started but non-repeating, stop it (as if it timed out). |
1524 | If the timer is started but non-repeating, stop it (as if it timed out). |
1339 | |
1525 | |
1340 | If the timer is repeating, either start it if necessary (with the |
1526 | If the timer is repeating, either start it if necessary (with the |
1341 | C<repeat> value), or reset the running timer to the C<repeat> value. |
1527 | C<repeat> value), or reset the running timer to the C<repeat> value. |
1342 | |
1528 | |
1343 | This sounds a bit complicated, but here is a useful and typical |
1529 | This sounds a bit complicated, see "Be smart about timeouts", above, for a |
1344 | example: Imagine you have a TCP connection and you want a so-called idle |
1530 | usage example. |
1345 | timeout, that is, you want to be called when there have been, say, 60 |
|
|
1346 | seconds of inactivity on the socket. The easiest way to do this is to |
|
|
1347 | configure an C<ev_timer> with a C<repeat> value of C<60> and then call |
|
|
1348 | C<ev_timer_again> each time you successfully read or write some data. If |
|
|
1349 | you go into an idle state where you do not expect data to travel on the |
|
|
1350 | socket, you can C<ev_timer_stop> the timer, and C<ev_timer_again> will |
|
|
1351 | automatically restart it if need be. |
|
|
1352 | |
|
|
1353 | That means you can ignore the C<after> value and C<ev_timer_start> |
|
|
1354 | altogether and only ever use the C<repeat> value and C<ev_timer_again>: |
|
|
1355 | |
|
|
1356 | ev_timer_init (timer, callback, 0., 5.); |
|
|
1357 | ev_timer_again (loop, timer); |
|
|
1358 | ... |
|
|
1359 | timer->again = 17.; |
|
|
1360 | ev_timer_again (loop, timer); |
|
|
1361 | ... |
|
|
1362 | timer->again = 10.; |
|
|
1363 | ev_timer_again (loop, timer); |
|
|
1364 | |
|
|
1365 | This is more slightly efficient then stopping/starting the timer each time |
|
|
1366 | you want to modify its timeout value. |
|
|
1367 | |
|
|
1368 | Note, however, that it is often even more efficient to remember the |
|
|
1369 | time of the last activity and let the timer time-out naturally. In the |
|
|
1370 | callback, you then check whether the time-out is real, or, if there was |
|
|
1371 | some activity, you reschedule the watcher to time-out in "last_activity + |
|
|
1372 | timeout - ev_now ()" seconds. |
|
|
1373 | |
1531 | |
1374 | =item ev_tstamp repeat [read-write] |
1532 | =item ev_tstamp repeat [read-write] |
1375 | |
1533 | |
1376 | The current C<repeat> value. Will be used each time the watcher times out |
1534 | The current C<repeat> value. Will be used each time the watcher times out |
1377 | or C<ev_timer_again> is called, and determines the next timeout (if any), |
1535 | or C<ev_timer_again> is called, and determines the next timeout (if any), |
… | |
… | |
1382 | =head3 Examples |
1540 | =head3 Examples |
1383 | |
1541 | |
1384 | Example: Create a timer that fires after 60 seconds. |
1542 | Example: Create a timer that fires after 60 seconds. |
1385 | |
1543 | |
1386 | static void |
1544 | static void |
1387 | one_minute_cb (struct ev_loop *loop, struct ev_timer *w, int revents) |
1545 | one_minute_cb (struct ev_loop *loop, ev_timer *w, int revents) |
1388 | { |
1546 | { |
1389 | .. one minute over, w is actually stopped right here |
1547 | .. one minute over, w is actually stopped right here |
1390 | } |
1548 | } |
1391 | |
1549 | |
1392 | struct ev_timer mytimer; |
1550 | ev_timer mytimer; |
1393 | ev_timer_init (&mytimer, one_minute_cb, 60., 0.); |
1551 | ev_timer_init (&mytimer, one_minute_cb, 60., 0.); |
1394 | ev_timer_start (loop, &mytimer); |
1552 | ev_timer_start (loop, &mytimer); |
1395 | |
1553 | |
1396 | Example: Create a timeout timer that times out after 10 seconds of |
1554 | Example: Create a timeout timer that times out after 10 seconds of |
1397 | inactivity. |
1555 | inactivity. |
1398 | |
1556 | |
1399 | static void |
1557 | static void |
1400 | timeout_cb (struct ev_loop *loop, struct ev_timer *w, int revents) |
1558 | timeout_cb (struct ev_loop *loop, ev_timer *w, int revents) |
1401 | { |
1559 | { |
1402 | .. ten seconds without any activity |
1560 | .. ten seconds without any activity |
1403 | } |
1561 | } |
1404 | |
1562 | |
1405 | struct ev_timer mytimer; |
1563 | ev_timer mytimer; |
1406 | ev_timer_init (&mytimer, timeout_cb, 0., 10.); /* note, only repeat used */ |
1564 | ev_timer_init (&mytimer, timeout_cb, 0., 10.); /* note, only repeat used */ |
1407 | ev_timer_again (&mytimer); /* start timer */ |
1565 | ev_timer_again (&mytimer); /* start timer */ |
1408 | ev_loop (loop, 0); |
1566 | ev_loop (loop, 0); |
1409 | |
1567 | |
1410 | // and in some piece of code that gets executed on any "activity": |
1568 | // and in some piece of code that gets executed on any "activity": |
… | |
… | |
1496 | |
1654 | |
1497 | If you need to stop it, return C<now + 1e30> (or so, fudge fudge) and stop |
1655 | If you need to stop it, return C<now + 1e30> (or so, fudge fudge) and stop |
1498 | it afterwards (e.g. by starting an C<ev_prepare> watcher, which is the |
1656 | it afterwards (e.g. by starting an C<ev_prepare> watcher, which is the |
1499 | only event loop modification you are allowed to do). |
1657 | only event loop modification you are allowed to do). |
1500 | |
1658 | |
1501 | The callback prototype is C<ev_tstamp (*reschedule_cb)(struct ev_periodic |
1659 | The callback prototype is C<ev_tstamp (*reschedule_cb)(ev_periodic |
1502 | *w, ev_tstamp now)>, e.g.: |
1660 | *w, ev_tstamp now)>, e.g.: |
1503 | |
1661 | |
|
|
1662 | static ev_tstamp |
1504 | static ev_tstamp my_rescheduler (struct ev_periodic *w, ev_tstamp now) |
1663 | my_rescheduler (ev_periodic *w, ev_tstamp now) |
1505 | { |
1664 | { |
1506 | return now + 60.; |
1665 | return now + 60.; |
1507 | } |
1666 | } |
1508 | |
1667 | |
1509 | It must return the next time to trigger, based on the passed time value |
1668 | It must return the next time to trigger, based on the passed time value |
… | |
… | |
1546 | |
1705 | |
1547 | The current interval value. Can be modified any time, but changes only |
1706 | The current interval value. Can be modified any time, but changes only |
1548 | take effect when the periodic timer fires or C<ev_periodic_again> is being |
1707 | take effect when the periodic timer fires or C<ev_periodic_again> is being |
1549 | called. |
1708 | called. |
1550 | |
1709 | |
1551 | =item ev_tstamp (*reschedule_cb)(struct ev_periodic *w, ev_tstamp now) [read-write] |
1710 | =item ev_tstamp (*reschedule_cb)(ev_periodic *w, ev_tstamp now) [read-write] |
1552 | |
1711 | |
1553 | The current reschedule callback, or C<0>, if this functionality is |
1712 | The current reschedule callback, or C<0>, if this functionality is |
1554 | switched off. Can be changed any time, but changes only take effect when |
1713 | switched off. Can be changed any time, but changes only take effect when |
1555 | the periodic timer fires or C<ev_periodic_again> is being called. |
1714 | the periodic timer fires or C<ev_periodic_again> is being called. |
1556 | |
1715 | |
… | |
… | |
1561 | Example: Call a callback every hour, or, more precisely, whenever the |
1720 | Example: Call a callback every hour, or, more precisely, whenever the |
1562 | system time is divisible by 3600. The callback invocation times have |
1721 | system time is divisible by 3600. The callback invocation times have |
1563 | potentially a lot of jitter, but good long-term stability. |
1722 | potentially a lot of jitter, but good long-term stability. |
1564 | |
1723 | |
1565 | static void |
1724 | static void |
1566 | clock_cb (struct ev_loop *loop, struct ev_io *w, int revents) |
1725 | clock_cb (struct ev_loop *loop, ev_io *w, int revents) |
1567 | { |
1726 | { |
1568 | ... its now a full hour (UTC, or TAI or whatever your clock follows) |
1727 | ... its now a full hour (UTC, or TAI or whatever your clock follows) |
1569 | } |
1728 | } |
1570 | |
1729 | |
1571 | struct ev_periodic hourly_tick; |
1730 | ev_periodic hourly_tick; |
1572 | ev_periodic_init (&hourly_tick, clock_cb, 0., 3600., 0); |
1731 | ev_periodic_init (&hourly_tick, clock_cb, 0., 3600., 0); |
1573 | ev_periodic_start (loop, &hourly_tick); |
1732 | ev_periodic_start (loop, &hourly_tick); |
1574 | |
1733 | |
1575 | Example: The same as above, but use a reschedule callback to do it: |
1734 | Example: The same as above, but use a reschedule callback to do it: |
1576 | |
1735 | |
1577 | #include <math.h> |
1736 | #include <math.h> |
1578 | |
1737 | |
1579 | static ev_tstamp |
1738 | static ev_tstamp |
1580 | my_scheduler_cb (struct ev_periodic *w, ev_tstamp now) |
1739 | my_scheduler_cb (ev_periodic *w, ev_tstamp now) |
1581 | { |
1740 | { |
1582 | return now + (3600. - fmod (now, 3600.)); |
1741 | return now + (3600. - fmod (now, 3600.)); |
1583 | } |
1742 | } |
1584 | |
1743 | |
1585 | ev_periodic_init (&hourly_tick, clock_cb, 0., 0., my_scheduler_cb); |
1744 | ev_periodic_init (&hourly_tick, clock_cb, 0., 0., my_scheduler_cb); |
1586 | |
1745 | |
1587 | Example: Call a callback every hour, starting now: |
1746 | Example: Call a callback every hour, starting now: |
1588 | |
1747 | |
1589 | struct ev_periodic hourly_tick; |
1748 | ev_periodic hourly_tick; |
1590 | ev_periodic_init (&hourly_tick, clock_cb, |
1749 | ev_periodic_init (&hourly_tick, clock_cb, |
1591 | fmod (ev_now (loop), 3600.), 3600., 0); |
1750 | fmod (ev_now (loop), 3600.), 3600., 0); |
1592 | ev_periodic_start (loop, &hourly_tick); |
1751 | ev_periodic_start (loop, &hourly_tick); |
1593 | |
1752 | |
1594 | |
1753 | |
… | |
… | |
1636 | =head3 Examples |
1795 | =head3 Examples |
1637 | |
1796 | |
1638 | Example: Try to exit cleanly on SIGINT. |
1797 | Example: Try to exit cleanly on SIGINT. |
1639 | |
1798 | |
1640 | static void |
1799 | static void |
1641 | sigint_cb (struct ev_loop *loop, struct ev_signal *w, int revents) |
1800 | sigint_cb (struct ev_loop *loop, ev_signal *w, int revents) |
1642 | { |
1801 | { |
1643 | ev_unloop (loop, EVUNLOOP_ALL); |
1802 | ev_unloop (loop, EVUNLOOP_ALL); |
1644 | } |
1803 | } |
1645 | |
1804 | |
1646 | struct ev_signal signal_watcher; |
1805 | ev_signal signal_watcher; |
1647 | ev_signal_init (&signal_watcher, sigint_cb, SIGINT); |
1806 | ev_signal_init (&signal_watcher, sigint_cb, SIGINT); |
1648 | ev_signal_start (loop, &signal_watcher); |
1807 | ev_signal_start (loop, &signal_watcher); |
1649 | |
1808 | |
1650 | |
1809 | |
1651 | =head2 C<ev_child> - watch out for process status changes |
1810 | =head2 C<ev_child> - watch out for process status changes |
… | |
… | |
1726 | its completion. |
1885 | its completion. |
1727 | |
1886 | |
1728 | ev_child cw; |
1887 | ev_child cw; |
1729 | |
1888 | |
1730 | static void |
1889 | static void |
1731 | child_cb (EV_P_ struct ev_child *w, int revents) |
1890 | child_cb (EV_P_ ev_child *w, int revents) |
1732 | { |
1891 | { |
1733 | ev_child_stop (EV_A_ w); |
1892 | ev_child_stop (EV_A_ w); |
1734 | printf ("process %d exited with status %x\n", w->rpid, w->rstatus); |
1893 | printf ("process %d exited with status %x\n", w->rpid, w->rstatus); |
1735 | } |
1894 | } |
1736 | |
1895 | |
… | |
… | |
1988 | |
2147 | |
1989 | Example: Dynamically allocate an C<ev_idle> watcher, start it, and in the |
2148 | Example: Dynamically allocate an C<ev_idle> watcher, start it, and in the |
1990 | callback, free it. Also, use no error checking, as usual. |
2149 | callback, free it. Also, use no error checking, as usual. |
1991 | |
2150 | |
1992 | static void |
2151 | static void |
1993 | idle_cb (struct ev_loop *loop, struct ev_idle *w, int revents) |
2152 | idle_cb (struct ev_loop *loop, ev_idle *w, int revents) |
1994 | { |
2153 | { |
1995 | free (w); |
2154 | free (w); |
1996 | // now do something you wanted to do when the program has |
2155 | // now do something you wanted to do when the program has |
1997 | // no longer anything immediate to do. |
2156 | // no longer anything immediate to do. |
1998 | } |
2157 | } |
1999 | |
2158 | |
2000 | struct ev_idle *idle_watcher = malloc (sizeof (struct ev_idle)); |
2159 | ev_idle *idle_watcher = malloc (sizeof (ev_idle)); |
2001 | ev_idle_init (idle_watcher, idle_cb); |
2160 | ev_idle_init (idle_watcher, idle_cb); |
2002 | ev_idle_start (loop, idle_cb); |
2161 | ev_idle_start (loop, idle_cb); |
2003 | |
2162 | |
2004 | |
2163 | |
2005 | =head2 C<ev_prepare> and C<ev_check> - customise your event loop! |
2164 | =head2 C<ev_prepare> and C<ev_check> - customise your event loop! |
… | |
… | |
2086 | |
2245 | |
2087 | static ev_io iow [nfd]; |
2246 | static ev_io iow [nfd]; |
2088 | static ev_timer tw; |
2247 | static ev_timer tw; |
2089 | |
2248 | |
2090 | static void |
2249 | static void |
2091 | io_cb (ev_loop *loop, ev_io *w, int revents) |
2250 | io_cb (struct ev_loop *loop, ev_io *w, int revents) |
2092 | { |
2251 | { |
2093 | } |
2252 | } |
2094 | |
2253 | |
2095 | // create io watchers for each fd and a timer before blocking |
2254 | // create io watchers for each fd and a timer before blocking |
2096 | static void |
2255 | static void |
2097 | adns_prepare_cb (ev_loop *loop, ev_prepare *w, int revents) |
2256 | adns_prepare_cb (struct ev_loop *loop, ev_prepare *w, int revents) |
2098 | { |
2257 | { |
2099 | int timeout = 3600000; |
2258 | int timeout = 3600000; |
2100 | struct pollfd fds [nfd]; |
2259 | struct pollfd fds [nfd]; |
2101 | // actual code will need to loop here and realloc etc. |
2260 | // actual code will need to loop here and realloc etc. |
2102 | adns_beforepoll (ads, fds, &nfd, &timeout, timeval_from (ev_time ())); |
2261 | adns_beforepoll (ads, fds, &nfd, &timeout, timeval_from (ev_time ())); |
… | |
… | |
2117 | } |
2276 | } |
2118 | } |
2277 | } |
2119 | |
2278 | |
2120 | // stop all watchers after blocking |
2279 | // stop all watchers after blocking |
2121 | static void |
2280 | static void |
2122 | adns_check_cb (ev_loop *loop, ev_check *w, int revents) |
2281 | adns_check_cb (struct ev_loop *loop, ev_check *w, int revents) |
2123 | { |
2282 | { |
2124 | ev_timer_stop (loop, &tw); |
2283 | ev_timer_stop (loop, &tw); |
2125 | |
2284 | |
2126 | for (int i = 0; i < nfd; ++i) |
2285 | for (int i = 0; i < nfd; ++i) |
2127 | { |
2286 | { |
… | |
… | |
2295 | C<loop_lo> (which is C<loop_hi> in the case no embeddable loop can be |
2454 | C<loop_lo> (which is C<loop_hi> in the case no embeddable loop can be |
2296 | used). |
2455 | used). |
2297 | |
2456 | |
2298 | struct ev_loop *loop_hi = ev_default_init (0); |
2457 | struct ev_loop *loop_hi = ev_default_init (0); |
2299 | struct ev_loop *loop_lo = 0; |
2458 | struct ev_loop *loop_lo = 0; |
2300 | struct ev_embed embed; |
2459 | ev_embed embed; |
2301 | |
2460 | |
2302 | // see if there is a chance of getting one that works |
2461 | // see if there is a chance of getting one that works |
2303 | // (remember that a flags value of 0 means autodetection) |
2462 | // (remember that a flags value of 0 means autodetection) |
2304 | loop_lo = ev_embeddable_backends () & ev_recommended_backends () |
2463 | loop_lo = ev_embeddable_backends () & ev_recommended_backends () |
2305 | ? ev_loop_new (ev_embeddable_backends () & ev_recommended_backends ()) |
2464 | ? ev_loop_new (ev_embeddable_backends () & ev_recommended_backends ()) |
… | |
… | |
2319 | kqueue implementation). Store the kqueue/socket-only event loop in |
2478 | kqueue implementation). Store the kqueue/socket-only event loop in |
2320 | C<loop_socket>. (One might optionally use C<EVFLAG_NOENV>, too). |
2479 | C<loop_socket>. (One might optionally use C<EVFLAG_NOENV>, too). |
2321 | |
2480 | |
2322 | struct ev_loop *loop = ev_default_init (0); |
2481 | struct ev_loop *loop = ev_default_init (0); |
2323 | struct ev_loop *loop_socket = 0; |
2482 | struct ev_loop *loop_socket = 0; |
2324 | struct ev_embed embed; |
2483 | ev_embed embed; |
2325 | |
2484 | |
2326 | if (ev_supported_backends () & ~ev_recommended_backends () & EVBACKEND_KQUEUE) |
2485 | if (ev_supported_backends () & ~ev_recommended_backends () & EVBACKEND_KQUEUE) |
2327 | if ((loop_socket = ev_loop_new (EVBACKEND_KQUEUE)) |
2486 | if ((loop_socket = ev_loop_new (EVBACKEND_KQUEUE)) |
2328 | { |
2487 | { |
2329 | ev_embed_init (&embed, 0, loop_socket); |
2488 | ev_embed_init (&embed, 0, loop_socket); |
… | |
… | |
2543 | /* doh, nothing entered */; |
2702 | /* doh, nothing entered */; |
2544 | } |
2703 | } |
2545 | |
2704 | |
2546 | ev_once (STDIN_FILENO, EV_READ, 10., stdin_ready, 0); |
2705 | ev_once (STDIN_FILENO, EV_READ, 10., stdin_ready, 0); |
2547 | |
2706 | |
2548 | =item ev_feed_event (ev_loop *, watcher *, int revents) |
2707 | =item ev_feed_event (struct ev_loop *, watcher *, int revents) |
2549 | |
2708 | |
2550 | Feeds the given event set into the event loop, as if the specified event |
2709 | Feeds the given event set into the event loop, as if the specified event |
2551 | had happened for the specified watcher (which must be a pointer to an |
2710 | had happened for the specified watcher (which must be a pointer to an |
2552 | initialised but not necessarily started event watcher). |
2711 | initialised but not necessarily started event watcher). |
2553 | |
2712 | |
2554 | =item ev_feed_fd_event (ev_loop *, int fd, int revents) |
2713 | =item ev_feed_fd_event (struct ev_loop *, int fd, int revents) |
2555 | |
2714 | |
2556 | Feed an event on the given fd, as if a file descriptor backend detected |
2715 | Feed an event on the given fd, as if a file descriptor backend detected |
2557 | the given events it. |
2716 | the given events it. |
2558 | |
2717 | |
2559 | =item ev_feed_signal_event (ev_loop *loop, int signum) |
2718 | =item ev_feed_signal_event (struct ev_loop *loop, int signum) |
2560 | |
2719 | |
2561 | Feed an event as if the given signal occurred (C<loop> must be the default |
2720 | Feed an event as if the given signal occurred (C<loop> must be the default |
2562 | loop!). |
2721 | loop!). |
2563 | |
2722 | |
2564 | =back |
2723 | =back |
… | |
… | |
2798 | |
2957 | |
2799 | =item D |
2958 | =item D |
2800 | |
2959 | |
2801 | Leandro Lucarella has written a D language binding (F<ev.d>) for libev, to |
2960 | Leandro Lucarella has written a D language binding (F<ev.d>) for libev, to |
2802 | be found at L<http://proj.llucax.com.ar/wiki/evd>. |
2961 | be found at L<http://proj.llucax.com.ar/wiki/evd>. |
|
|
2962 | |
|
|
2963 | =item Ocaml |
|
|
2964 | |
|
|
2965 | Erkki Seppala has written Ocaml bindings for libev, to be found at |
|
|
2966 | L<http://modeemi.cs.tut.fi/~flux/software/ocaml-ev/>. |
2803 | |
2967 | |
2804 | =back |
2968 | =back |
2805 | |
2969 | |
2806 | |
2970 | |
2807 | =head1 MACRO MAGIC |
2971 | =head1 MACRO MAGIC |