… | |
… | |
63 | details of the event, and then hand it over to libev by I<starting> the |
63 | details of the event, and then hand it over to libev by I<starting> the |
64 | watcher. |
64 | watcher. |
65 | |
65 | |
66 | =head1 FEATURES |
66 | =head1 FEATURES |
67 | |
67 | |
68 | Libev supports C<select>, C<poll>, the linux-specific C<epoll>, the |
68 | Libev supports C<select>, C<poll>, the Linux-specific C<epoll>, the |
69 | bsd-specific C<kqueue> and the solaris-specific event port mechanisms |
69 | BSD-specific C<kqueue> and the Solaris-specific event port mechanisms |
70 | for file descriptor events (C<ev_io>), relative timers (C<ev_timer>), |
70 | for file descriptor events (C<ev_io>), the Linux C<inotify> interface |
|
|
71 | (for C<ev_stat>), relative timers (C<ev_timer>), absolute timers |
71 | absolute timers with customised rescheduling (C<ev_periodic>), synchronous |
72 | with customised rescheduling (C<ev_periodic>), synchronous signals |
72 | signals (C<ev_signal>), process status change events (C<ev_child>), and |
73 | (C<ev_signal>), process status change events (C<ev_child>), and event |
73 | event watchers dealing with the event loop mechanism itself (C<ev_idle>, |
74 | watchers dealing with the event loop mechanism itself (C<ev_idle>, |
74 | C<ev_embed>, C<ev_prepare> and C<ev_check> watchers) as well as |
75 | C<ev_embed>, C<ev_prepare> and C<ev_check> watchers) as well as |
75 | file watchers (C<ev_stat>) and even limited support for fork events |
76 | file watchers (C<ev_stat>) and even limited support for fork events |
76 | (C<ev_fork>). |
77 | (C<ev_fork>). |
77 | |
78 | |
78 | It also is quite fast (see this |
79 | It also is quite fast (see this |
… | |
… | |
162 | C<ev_embeddable_backends () & ev_supported_backends ()>, likewise for |
163 | C<ev_embeddable_backends () & ev_supported_backends ()>, likewise for |
163 | recommended ones. |
164 | recommended ones. |
164 | |
165 | |
165 | See the description of C<ev_embed> watchers for more info. |
166 | See the description of C<ev_embed> watchers for more info. |
166 | |
167 | |
167 | =item ev_set_allocator (void *(*cb)(void *ptr, size_t size)) |
168 | =item ev_set_allocator (void *(*cb)(void *ptr, long size)) |
168 | |
169 | |
169 | Sets the allocation function to use (the prototype and semantics are |
170 | Sets the allocation function to use (the prototype is similar - the |
170 | identical to the realloc C function). It is used to allocate and free |
171 | semantics is identical - to the realloc C function). It is used to |
171 | memory (no surprises here). If it returns zero when memory needs to be |
172 | allocate and free memory (no surprises here). If it returns zero when |
172 | allocated, the library might abort or take some potentially destructive |
173 | memory needs to be allocated, the library might abort or take some |
173 | action. The default is your system realloc function. |
174 | potentially destructive action. The default is your system realloc |
|
|
175 | function. |
174 | |
176 | |
175 | You could override this function in high-availability programs to, say, |
177 | You could override this function in high-availability programs to, say, |
176 | free some memory if it cannot allocate memory, to use a special allocator, |
178 | free some memory if it cannot allocate memory, to use a special allocator, |
177 | or even to sleep a while and retry until some memory is available. |
179 | or even to sleep a while and retry until some memory is available. |
178 | |
180 | |
… | |
… | |
264 | C<LIBEV_FLAGS>. Otherwise (the default), this environment variable will |
266 | C<LIBEV_FLAGS>. Otherwise (the default), this environment variable will |
265 | override the flags completely if it is found in the environment. This is |
267 | override the flags completely if it is found in the environment. This is |
266 | useful to try out specific backends to test their performance, or to work |
268 | useful to try out specific backends to test their performance, or to work |
267 | around bugs. |
269 | around bugs. |
268 | |
270 | |
|
|
271 | =item C<EVFLAG_FORKCHECK> |
|
|
272 | |
|
|
273 | Instead of calling C<ev_default_fork> or C<ev_loop_fork> manually after |
|
|
274 | a fork, you can also make libev check for a fork in each iteration by |
|
|
275 | enabling this flag. |
|
|
276 | |
|
|
277 | This works by calling C<getpid ()> on every iteration of the loop, |
|
|
278 | and thus this might slow down your event loop if you do a lot of loop |
|
|
279 | iterations and little real work, but is usually not noticeable (on my |
|
|
280 | Linux system for example, C<getpid> is actually a simple 5-insn sequence |
|
|
281 | without a syscall and thus I<very> fast, but my Linux system also has |
|
|
282 | C<pthread_atfork> which is even faster). |
|
|
283 | |
|
|
284 | The big advantage of this flag is that you can forget about fork (and |
|
|
285 | forget about forgetting to tell libev about forking) when you use this |
|
|
286 | flag. |
|
|
287 | |
|
|
288 | This flag setting cannot be overriden or specified in the C<LIBEV_FLAGS> |
|
|
289 | environment variable. |
|
|
290 | |
269 | =item C<EVBACKEND_SELECT> (value 1, portable select backend) |
291 | =item C<EVBACKEND_SELECT> (value 1, portable select backend) |
270 | |
292 | |
271 | This is your standard select(2) backend. Not I<completely> standard, as |
293 | This is your standard select(2) backend. Not I<completely> standard, as |
272 | libev tries to roll its own fd_set with no limits on the number of fds, |
294 | libev tries to roll its own fd_set with no limits on the number of fds, |
273 | but if that fails, expect a fairly low limit on the number of fds when |
295 | but if that fails, expect a fairly low limit on the number of fds when |
… | |
… | |
407 | =item ev_loop_fork (loop) |
429 | =item ev_loop_fork (loop) |
408 | |
430 | |
409 | Like C<ev_default_fork>, but acts on an event loop created by |
431 | Like C<ev_default_fork>, but acts on an event loop created by |
410 | C<ev_loop_new>. Yes, you have to call this on every allocated event loop |
432 | C<ev_loop_new>. Yes, you have to call this on every allocated event loop |
411 | after fork, and how you do this is entirely your own problem. |
433 | after fork, and how you do this is entirely your own problem. |
|
|
434 | |
|
|
435 | =item unsigned int ev_loop_count (loop) |
|
|
436 | |
|
|
437 | Returns the count of loop iterations for the loop, which is identical to |
|
|
438 | the number of times libev did poll for new events. It starts at C<0> and |
|
|
439 | happily wraps around with enough iterations. |
|
|
440 | |
|
|
441 | This value can sometimes be useful as a generation counter of sorts (it |
|
|
442 | "ticks" the number of loop iterations), as it roughly corresponds with |
|
|
443 | C<ev_prepare> and C<ev_check> calls. |
412 | |
444 | |
413 | =item unsigned int ev_backend (loop) |
445 | =item unsigned int ev_backend (loop) |
414 | |
446 | |
415 | Returns one of the C<EVBACKEND_*> flags indicating the event backend in |
447 | Returns one of the C<EVBACKEND_*> flags indicating the event backend in |
416 | use. |
448 | use. |
… | |
… | |
703 | events but its callback has not yet been invoked). As long as a watcher |
735 | events but its callback has not yet been invoked). As long as a watcher |
704 | is pending (but not active) you must not call an init function on it (but |
736 | is pending (but not active) you must not call an init function on it (but |
705 | C<ev_TYPE_set> is safe) and you must make sure the watcher is available to |
737 | C<ev_TYPE_set> is safe) and you must make sure the watcher is available to |
706 | libev (e.g. you cnanot C<free ()> it). |
738 | libev (e.g. you cnanot C<free ()> it). |
707 | |
739 | |
708 | =item callback = ev_cb (ev_TYPE *watcher) |
740 | =item callback ev_cb (ev_TYPE *watcher) |
709 | |
741 | |
710 | Returns the callback currently set on the watcher. |
742 | Returns the callback currently set on the watcher. |
711 | |
743 | |
712 | =item ev_cb_set (ev_TYPE *watcher, callback) |
744 | =item ev_cb_set (ev_TYPE *watcher, callback) |
713 | |
745 | |
714 | Change the callback. You can change the callback at virtually any time |
746 | Change the callback. You can change the callback at virtually any time |
715 | (modulo threads). |
747 | (modulo threads). |
|
|
748 | |
|
|
749 | =item ev_set_priority (ev_TYPE *watcher, priority) |
|
|
750 | |
|
|
751 | =item int ev_priority (ev_TYPE *watcher) |
|
|
752 | |
|
|
753 | Set and query the priority of the watcher. The priority is a small |
|
|
754 | integer between C<EV_MAXPRI> (default: C<2>) and C<EV_MINPRI> |
|
|
755 | (default: C<-2>). Pending watchers with higher priority will be invoked |
|
|
756 | before watchers with lower priority, but priority will not keep watchers |
|
|
757 | from being executed (except for C<ev_idle> watchers). |
|
|
758 | |
|
|
759 | This means that priorities are I<only> used for ordering callback |
|
|
760 | invocation after new events have been received. This is useful, for |
|
|
761 | example, to reduce latency after idling, or more often, to bind two |
|
|
762 | watchers on the same event and make sure one is called first. |
|
|
763 | |
|
|
764 | If you need to suppress invocation when higher priority events are pending |
|
|
765 | you need to look at C<ev_idle> watchers, which provide this functionality. |
|
|
766 | |
|
|
767 | The default priority used by watchers when no priority has been set is |
|
|
768 | always C<0>, which is supposed to not be too high and not be too low :). |
|
|
769 | |
|
|
770 | Setting a priority outside the range of C<EV_MINPRI> to C<EV_MAXPRI> is |
|
|
771 | fine, as long as you do not mind that the priority value you query might |
|
|
772 | or might not have been adjusted to be within valid range. |
716 | |
773 | |
717 | =back |
774 | =back |
718 | |
775 | |
719 | |
776 | |
720 | =head2 ASSOCIATING CUSTOM DATA WITH A WATCHER |
777 | =head2 ASSOCIATING CUSTOM DATA WITH A WATCHER |
… | |
… | |
741 | { |
798 | { |
742 | struct my_io *w = (struct my_io *)w_; |
799 | struct my_io *w = (struct my_io *)w_; |
743 | ... |
800 | ... |
744 | } |
801 | } |
745 | |
802 | |
746 | More interesting and less C-conformant ways of catsing your callback type |
803 | More interesting and less C-conformant ways of casting your callback type |
747 | have been omitted.... |
804 | instead have been omitted. |
|
|
805 | |
|
|
806 | Another common scenario is having some data structure with multiple |
|
|
807 | watchers: |
|
|
808 | |
|
|
809 | struct my_biggy |
|
|
810 | { |
|
|
811 | int some_data; |
|
|
812 | ev_timer t1; |
|
|
813 | ev_timer t2; |
|
|
814 | } |
|
|
815 | |
|
|
816 | In this case getting the pointer to C<my_biggy> is a bit more complicated, |
|
|
817 | you need to use C<offsetof>: |
|
|
818 | |
|
|
819 | #include <stddef.h> |
|
|
820 | |
|
|
821 | static void |
|
|
822 | t1_cb (EV_P_ struct ev_timer *w, int revents) |
|
|
823 | { |
|
|
824 | struct my_biggy big = (struct my_biggy * |
|
|
825 | (((char *)w) - offsetof (struct my_biggy, t1)); |
|
|
826 | } |
|
|
827 | |
|
|
828 | static void |
|
|
829 | t2_cb (EV_P_ struct ev_timer *w, int revents) |
|
|
830 | { |
|
|
831 | struct my_biggy big = (struct my_biggy * |
|
|
832 | (((char *)w) - offsetof (struct my_biggy, t2)); |
|
|
833 | } |
748 | |
834 | |
749 | |
835 | |
750 | =head1 WATCHER TYPES |
836 | =head1 WATCHER TYPES |
751 | |
837 | |
752 | This section describes each watcher in detail, but will not repeat |
838 | This section describes each watcher in detail, but will not repeat |
… | |
… | |
885 | =item ev_timer_again (loop) |
971 | =item ev_timer_again (loop) |
886 | |
972 | |
887 | This will act as if the timer timed out and restart it again if it is |
973 | This will act as if the timer timed out and restart it again if it is |
888 | repeating. The exact semantics are: |
974 | repeating. The exact semantics are: |
889 | |
975 | |
|
|
976 | If the timer is pending, its pending status is cleared. |
|
|
977 | |
890 | If the timer is started but nonrepeating, stop it. |
978 | If the timer is started but nonrepeating, stop it (as if it timed out). |
891 | |
979 | |
892 | If the timer is repeating, either start it if necessary (with the repeat |
980 | If the timer is repeating, either start it if necessary (with the |
893 | value), or reset the running timer to the repeat value. |
981 | C<repeat> value), or reset the running timer to the C<repeat> value. |
894 | |
982 | |
895 | This sounds a bit complicated, but here is a useful and typical |
983 | This sounds a bit complicated, but here is a useful and typical |
896 | example: Imagine you have a tcp connection and you want a so-called |
984 | example: Imagine you have a tcp connection and you want a so-called idle |
897 | idle timeout, that is, you want to be called when there have been, |
985 | timeout, that is, you want to be called when there have been, say, 60 |
898 | say, 60 seconds of inactivity on the socket. The easiest way to do |
986 | seconds of inactivity on the socket. The easiest way to do this is to |
899 | this is to configure an C<ev_timer> with C<after>=C<repeat>=C<60> and calling |
987 | configure an C<ev_timer> with a C<repeat> value of C<60> and then call |
900 | C<ev_timer_again> each time you successfully read or write some data. If |
988 | C<ev_timer_again> each time you successfully read or write some data. If |
901 | you go into an idle state where you do not expect data to travel on the |
989 | you go into an idle state where you do not expect data to travel on the |
902 | socket, you can stop the timer, and again will automatically restart it if |
990 | socket, you can C<ev_timer_stop> the timer, and C<ev_timer_again> will |
903 | need be. |
991 | automatically restart it if need be. |
904 | |
992 | |
905 | You can also ignore the C<after> value and C<ev_timer_start> altogether |
993 | That means you can ignore the C<after> value and C<ev_timer_start> |
906 | and only ever use the C<repeat> value: |
994 | altogether and only ever use the C<repeat> value and C<ev_timer_again>: |
907 | |
995 | |
908 | ev_timer_init (timer, callback, 0., 5.); |
996 | ev_timer_init (timer, callback, 0., 5.); |
909 | ev_timer_again (loop, timer); |
997 | ev_timer_again (loop, timer); |
910 | ... |
998 | ... |
911 | timer->again = 17.; |
999 | timer->again = 17.; |
912 | ev_timer_again (loop, timer); |
1000 | ev_timer_again (loop, timer); |
913 | ... |
1001 | ... |
914 | timer->again = 10.; |
1002 | timer->again = 10.; |
915 | ev_timer_again (loop, timer); |
1003 | ev_timer_again (loop, timer); |
916 | |
1004 | |
917 | This is more efficient then stopping/starting the timer eahc time you want |
1005 | This is more slightly efficient then stopping/starting the timer each time |
918 | to modify its timeout value. |
1006 | you want to modify its timeout value. |
919 | |
1007 | |
920 | =item ev_tstamp repeat [read-write] |
1008 | =item ev_tstamp repeat [read-write] |
921 | |
1009 | |
922 | The current C<repeat> value. Will be used each time the watcher times out |
1010 | The current C<repeat> value. Will be used each time the watcher times out |
923 | or C<ev_timer_again> is called and determines the next timeout (if any), |
1011 | or C<ev_timer_again> is called and determines the next timeout (if any), |
… | |
… | |
1192 | not exist" is a status change like any other. The condition "path does |
1280 | not exist" is a status change like any other. The condition "path does |
1193 | not exist" is signified by the C<st_nlink> field being zero (which is |
1281 | not exist" is signified by the C<st_nlink> field being zero (which is |
1194 | otherwise always forced to be at least one) and all the other fields of |
1282 | otherwise always forced to be at least one) and all the other fields of |
1195 | the stat buffer having unspecified contents. |
1283 | the stat buffer having unspecified contents. |
1196 | |
1284 | |
|
|
1285 | The path I<should> be absolute and I<must not> end in a slash. If it is |
|
|
1286 | relative and your working directory changes, the behaviour is undefined. |
|
|
1287 | |
1197 | Since there is no standard to do this, the portable implementation simply |
1288 | Since there is no standard to do this, the portable implementation simply |
1198 | calls C<stat (2)> regulalry on the path to see if it changed somehow. You |
1289 | calls C<stat (2)> regularly on the path to see if it changed somehow. You |
1199 | can specify a recommended polling interval for this case. If you specify |
1290 | can specify a recommended polling interval for this case. If you specify |
1200 | a polling interval of C<0> (highly recommended!) then a I<suitable, |
1291 | a polling interval of C<0> (highly recommended!) then a I<suitable, |
1201 | unspecified default> value will be used (which you can expect to be around |
1292 | unspecified default> value will be used (which you can expect to be around |
1202 | five seconds, although this might change dynamically). Libev will also |
1293 | five seconds, although this might change dynamically). Libev will also |
1203 | impose a minimum interval which is currently around C<0.1>, but thats |
1294 | impose a minimum interval which is currently around C<0.1>, but thats |
… | |
… | |
1205 | |
1296 | |
1206 | This watcher type is not meant for massive numbers of stat watchers, |
1297 | This watcher type is not meant for massive numbers of stat watchers, |
1207 | as even with OS-supported change notifications, this can be |
1298 | as even with OS-supported change notifications, this can be |
1208 | resource-intensive. |
1299 | resource-intensive. |
1209 | |
1300 | |
1210 | At the time of this writing, no specific OS backends are implemented, but |
1301 | At the time of this writing, only the Linux inotify interface is |
1211 | if demand increases, at least a kqueue and inotify backend will be added. |
1302 | implemented (implementing kqueue support is left as an exercise for the |
|
|
1303 | reader). Inotify will be used to give hints only and should not change the |
|
|
1304 | semantics of C<ev_stat> watchers, which means that libev sometimes needs |
|
|
1305 | to fall back to regular polling again even with inotify, but changes are |
|
|
1306 | usually detected immediately, and if the file exists there will be no |
|
|
1307 | polling. |
1212 | |
1308 | |
1213 | =over 4 |
1309 | =over 4 |
1214 | |
1310 | |
1215 | =item ev_stat_init (ev_stat *, callback, const char *path, ev_tstamp interval) |
1311 | =item ev_stat_init (ev_stat *, callback, const char *path, ev_tstamp interval) |
1216 | |
1312 | |
… | |
… | |
1280 | ev_stat_start (loop, &passwd); |
1376 | ev_stat_start (loop, &passwd); |
1281 | |
1377 | |
1282 | |
1378 | |
1283 | =head2 C<ev_idle> - when you've got nothing better to do... |
1379 | =head2 C<ev_idle> - when you've got nothing better to do... |
1284 | |
1380 | |
1285 | Idle watchers trigger events when there are no other events are pending |
1381 | Idle watchers trigger events when no other events of the same or higher |
1286 | (prepare, check and other idle watchers do not count). That is, as long |
1382 | priority are pending (prepare, check and other idle watchers do not |
1287 | as your process is busy handling sockets or timeouts (or even signals, |
1383 | count). |
1288 | imagine) it will not be triggered. But when your process is idle all idle |
1384 | |
1289 | watchers are being called again and again, once per event loop iteration - |
1385 | That is, as long as your process is busy handling sockets or timeouts |
|
|
1386 | (or even signals, imagine) of the same or higher priority it will not be |
|
|
1387 | triggered. But when your process is idle (or only lower-priority watchers |
|
|
1388 | are pending), the idle watchers are being called once per event loop |
1290 | until stopped, that is, or your process receives more events and becomes |
1389 | iteration - until stopped, that is, or your process receives more events |
1291 | busy. |
1390 | and becomes busy again with higher priority stuff. |
1292 | |
1391 | |
1293 | The most noteworthy effect is that as long as any idle watchers are |
1392 | The most noteworthy effect is that as long as any idle watchers are |
1294 | active, the process will not block when waiting for new events. |
1393 | active, the process will not block when waiting for new events. |
1295 | |
1394 | |
1296 | Apart from keeping your process non-blocking (which is a useful |
1395 | Apart from keeping your process non-blocking (which is a useful |
… | |
… | |
1396 | |
1495 | |
1397 | // create io watchers for each fd and a timer before blocking |
1496 | // create io watchers for each fd and a timer before blocking |
1398 | static void |
1497 | static void |
1399 | adns_prepare_cb (ev_loop *loop, ev_prepare *w, int revents) |
1498 | adns_prepare_cb (ev_loop *loop, ev_prepare *w, int revents) |
1400 | { |
1499 | { |
1401 | int timeout = 3600000;truct pollfd fds [nfd]; |
1500 | int timeout = 3600000; |
|
|
1501 | struct pollfd fds [nfd]; |
1402 | // actual code will need to loop here and realloc etc. |
1502 | // actual code will need to loop here and realloc etc. |
1403 | adns_beforepoll (ads, fds, &nfd, &timeout, timeval_from (ev_time ())); |
1503 | adns_beforepoll (ads, fds, &nfd, &timeout, timeval_from (ev_time ())); |
1404 | |
1504 | |
1405 | /* the callback is illegal, but won't be called as we stop during check */ |
1505 | /* the callback is illegal, but won't be called as we stop during check */ |
1406 | ev_timer_init (&tw, 0, timeout * 1e-3); |
1506 | ev_timer_init (&tw, 0, timeout * 1e-3); |
… | |
… | |
1787 | Similar to the other two macros, this gives you the value of the default |
1887 | Similar to the other two macros, this gives you the value of the default |
1788 | loop, if multiple loops are supported ("ev loop default"). |
1888 | loop, if multiple loops are supported ("ev loop default"). |
1789 | |
1889 | |
1790 | =back |
1890 | =back |
1791 | |
1891 | |
1792 | Example: Declare and initialise a check watcher, working regardless of |
1892 | Example: Declare and initialise a check watcher, utilising the above |
1793 | wether multiple loops are supported or not. |
1893 | macros so it will work regardless of wether multiple loops are supported |
|
|
1894 | or not. |
1794 | |
1895 | |
1795 | static void |
1896 | static void |
1796 | check_cb (EV_P_ ev_timer *w, int revents) |
1897 | check_cb (EV_P_ ev_timer *w, int revents) |
1797 | { |
1898 | { |
1798 | ev_check_stop (EV_A_ w); |
1899 | ev_check_stop (EV_A_ w); |
… | |
… | |
1800 | |
1901 | |
1801 | ev_check check; |
1902 | ev_check check; |
1802 | ev_check_init (&check, check_cb); |
1903 | ev_check_init (&check, check_cb); |
1803 | ev_check_start (EV_DEFAULT_ &check); |
1904 | ev_check_start (EV_DEFAULT_ &check); |
1804 | ev_loop (EV_DEFAULT_ 0); |
1905 | ev_loop (EV_DEFAULT_ 0); |
1805 | |
|
|
1806 | |
1906 | |
1807 | =head1 EMBEDDING |
1907 | =head1 EMBEDDING |
1808 | |
1908 | |
1809 | Libev can (and often is) directly embedded into host |
1909 | Libev can (and often is) directly embedded into host |
1810 | applications. Examples of applications that embed it include the Deliantra |
1910 | applications. Examples of applications that embed it include the Deliantra |
… | |
… | |
1850 | ev_vars.h |
1950 | ev_vars.h |
1851 | ev_wrap.h |
1951 | ev_wrap.h |
1852 | |
1952 | |
1853 | ev_win32.c required on win32 platforms only |
1953 | ev_win32.c required on win32 platforms only |
1854 | |
1954 | |
1855 | ev_select.c only when select backend is enabled (which is by default) |
1955 | ev_select.c only when select backend is enabled (which is enabled by default) |
1856 | ev_poll.c only when poll backend is enabled (disabled by default) |
1956 | ev_poll.c only when poll backend is enabled (disabled by default) |
1857 | ev_epoll.c only when the epoll backend is enabled (disabled by default) |
1957 | ev_epoll.c only when the epoll backend is enabled (disabled by default) |
1858 | ev_kqueue.c only when the kqueue backend is enabled (disabled by default) |
1958 | ev_kqueue.c only when the kqueue backend is enabled (disabled by default) |
1859 | ev_port.c only when the solaris port backend is enabled (disabled by default) |
1959 | ev_port.c only when the solaris port backend is enabled (disabled by default) |
1860 | |
1960 | |
… | |
… | |
1985 | |
2085 | |
1986 | =item EV_USE_DEVPOLL |
2086 | =item EV_USE_DEVPOLL |
1987 | |
2087 | |
1988 | reserved for future expansion, works like the USE symbols above. |
2088 | reserved for future expansion, works like the USE symbols above. |
1989 | |
2089 | |
|
|
2090 | =item EV_USE_INOTIFY |
|
|
2091 | |
|
|
2092 | If defined to be C<1>, libev will compile in support for the Linux inotify |
|
|
2093 | interface to speed up C<ev_stat> watchers. Its actual availability will |
|
|
2094 | be detected at runtime. |
|
|
2095 | |
1990 | =item EV_H |
2096 | =item EV_H |
1991 | |
2097 | |
1992 | The name of the F<ev.h> header file used to include it. The default if |
2098 | The name of the F<ev.h> header file used to include it. The default if |
1993 | undefined is C<< <ev.h> >> in F<event.h> and C<"ev.h"> in F<ev.c>. This |
2099 | undefined is C<< <ev.h> >> in F<event.h> and C<"ev.h"> in F<ev.c>. This |
1994 | can be used to virtually rename the F<ev.h> header file in case of conflicts. |
2100 | can be used to virtually rename the F<ev.h> header file in case of conflicts. |
… | |
… | |
2023 | |
2129 | |
2024 | If undefined or defined to be C<1>, then periodic timers are supported. If |
2130 | If undefined or defined to be C<1>, then periodic timers are supported. If |
2025 | defined to be C<0>, then they are not. Disabling them saves a few kB of |
2131 | defined to be C<0>, then they are not. Disabling them saves a few kB of |
2026 | code. |
2132 | code. |
2027 | |
2133 | |
|
|
2134 | =item EV_IDLE_ENABLE |
|
|
2135 | |
|
|
2136 | If undefined or defined to be C<1>, then idle watchers are supported. If |
|
|
2137 | defined to be C<0>, then they are not. Disabling them saves a few kB of |
|
|
2138 | code. |
|
|
2139 | |
2028 | =item EV_EMBED_ENABLE |
2140 | =item EV_EMBED_ENABLE |
2029 | |
2141 | |
2030 | If undefined or defined to be C<1>, then embed watchers are supported. If |
2142 | If undefined or defined to be C<1>, then embed watchers are supported. If |
2031 | defined to be C<0>, then they are not. |
2143 | defined to be C<0>, then they are not. |
2032 | |
2144 | |
… | |
… | |
2049 | =item EV_PID_HASHSIZE |
2161 | =item EV_PID_HASHSIZE |
2050 | |
2162 | |
2051 | C<ev_child> watchers use a small hash table to distribute workload by |
2163 | C<ev_child> watchers use a small hash table to distribute workload by |
2052 | pid. The default size is C<16> (or C<1> with C<EV_MINIMAL>), usually more |
2164 | pid. The default size is C<16> (or C<1> with C<EV_MINIMAL>), usually more |
2053 | than enough. If you need to manage thousands of children you might want to |
2165 | than enough. If you need to manage thousands of children you might want to |
2054 | increase this value. |
2166 | increase this value (I<must> be a power of two). |
|
|
2167 | |
|
|
2168 | =item EV_INOTIFY_HASHSIZE |
|
|
2169 | |
|
|
2170 | C<ev_staz> watchers use a small hash table to distribute workload by |
|
|
2171 | inotify watch id. The default size is C<16> (or C<1> with C<EV_MINIMAL>), |
|
|
2172 | usually more than enough. If you need to manage thousands of C<ev_stat> |
|
|
2173 | watchers you might want to increase this value (I<must> be a power of |
|
|
2174 | two). |
2055 | |
2175 | |
2056 | =item EV_COMMON |
2176 | =item EV_COMMON |
2057 | |
2177 | |
2058 | By default, all watchers have a C<void *data> member. By redefining |
2178 | By default, all watchers have a C<void *data> member. By redefining |
2059 | this macro to a something else you can include more and other types of |
2179 | this macro to a something else you can include more and other types of |
… | |
… | |
2088 | interface) and F<EV.xs> (implementation) files. Only the F<EV.xs> file |
2208 | interface) and F<EV.xs> (implementation) files. Only the F<EV.xs> file |
2089 | will be compiled. It is pretty complex because it provides its own header |
2209 | will be compiled. It is pretty complex because it provides its own header |
2090 | file. |
2210 | file. |
2091 | |
2211 | |
2092 | The usage in rxvt-unicode is simpler. It has a F<ev_cpp.h> header file |
2212 | The usage in rxvt-unicode is simpler. It has a F<ev_cpp.h> header file |
2093 | that everybody includes and which overrides some autoconf choices: |
2213 | that everybody includes and which overrides some configure choices: |
2094 | |
2214 | |
|
|
2215 | #define EV_MINIMAL 1 |
2095 | #define EV_USE_POLL 0 |
2216 | #define EV_USE_POLL 0 |
2096 | #define EV_MULTIPLICITY 0 |
2217 | #define EV_MULTIPLICITY 0 |
2097 | #define EV_PERIODICS 0 |
2218 | #define EV_PERIODIC_ENABLE 0 |
|
|
2219 | #define EV_STAT_ENABLE 0 |
|
|
2220 | #define EV_FORK_ENABLE 0 |
2098 | #define EV_CONFIG_H <config.h> |
2221 | #define EV_CONFIG_H <config.h> |
|
|
2222 | #define EV_MINPRI 0 |
|
|
2223 | #define EV_MAXPRI 0 |
2099 | |
2224 | |
2100 | #include "ev++.h" |
2225 | #include "ev++.h" |
2101 | |
2226 | |
2102 | And a F<ev_cpp.C> implementation file that contains libev proper and is compiled: |
2227 | And a F<ev_cpp.C> implementation file that contains libev proper and is compiled: |
2103 | |
2228 | |
… | |
… | |
2119 | |
2244 | |
2120 | =item Starting io/check/prepare/idle/signal/child watchers: O(1) |
2245 | =item Starting io/check/prepare/idle/signal/child watchers: O(1) |
2121 | |
2246 | |
2122 | =item Stopping check/prepare/idle watchers: O(1) |
2247 | =item Stopping check/prepare/idle watchers: O(1) |
2123 | |
2248 | |
2124 | =item Stopping an io/signal/child watcher: O(number_of_watchers_for_this_(fd/signal/pid % 16)) |
2249 | =item Stopping an io/signal/child watcher: O(number_of_watchers_for_this_(fd/signal/pid % EV_PID_HASHSIZE)) |
2125 | |
2250 | |
2126 | =item Finding the next timer per loop iteration: O(1) |
2251 | =item Finding the next timer per loop iteration: O(1) |
2127 | |
2252 | |
2128 | =item Each change on a file descriptor per loop iteration: O(number_of_watchers_for_this_fd) |
2253 | =item Each change on a file descriptor per loop iteration: O(number_of_watchers_for_this_fd) |
2129 | |
2254 | |