… | |
… | |
127 | .\} |
127 | .\} |
128 | .rm #[ #] #H #V #F C |
128 | .rm #[ #] #H #V #F C |
129 | .\" ======================================================================== |
129 | .\" ======================================================================== |
130 | .\" |
130 | .\" |
131 | .IX Title ""<STANDARD INPUT>" 1" |
131 | .IX Title ""<STANDARD INPUT>" 1" |
132 | .TH "<STANDARD INPUT>" 1 "2007-11-27" "perl v5.8.8" "User Contributed Perl Documentation" |
132 | .TH "<STANDARD INPUT>" 1 "2007-12-07" "perl v5.8.8" "User Contributed Perl Documentation" |
133 | .SH "NAME" |
133 | .SH "NAME" |
134 | libev \- a high performance full\-featured event loop written in C |
134 | libev \- a high performance full\-featured event loop written in C |
135 | .SH "SYNOPSIS" |
135 | .SH "SYNOPSIS" |
136 | .IX Header "SYNOPSIS" |
136 | .IX Header "SYNOPSIS" |
|
|
137 | .Vb 1 |
|
|
138 | \& #include <ev.h> |
|
|
139 | .Ve |
|
|
140 | .SH "EXAMPLE PROGRAM" |
|
|
141 | .IX Header "EXAMPLE PROGRAM" |
|
|
142 | .Vb 1 |
|
|
143 | \& #include <ev.h> |
|
|
144 | .Ve |
|
|
145 | .PP |
137 | .Vb 2 |
146 | .Vb 2 |
138 | \& /* this is the only header you need */ |
|
|
139 | \& #include <ev.h> |
|
|
140 | .Ve |
|
|
141 | .PP |
|
|
142 | .Vb 3 |
|
|
143 | \& /* what follows is a fully working example program */ |
|
|
144 | \& ev_io stdin_watcher; |
147 | \& ev_io stdin_watcher; |
145 | \& ev_timer timeout_watcher; |
148 | \& ev_timer timeout_watcher; |
146 | .Ve |
149 | .Ve |
147 | .PP |
150 | .PP |
148 | .Vb 8 |
151 | .Vb 8 |
… | |
… | |
207 | watchers\fR, which are relatively small C structures you initialise with the |
210 | watchers\fR, which are relatively small C structures you initialise with the |
208 | details of the event, and then hand it over to libev by \fIstarting\fR the |
211 | details of the event, and then hand it over to libev by \fIstarting\fR the |
209 | watcher. |
212 | watcher. |
210 | .SH "FEATURES" |
213 | .SH "FEATURES" |
211 | .IX Header "FEATURES" |
214 | .IX Header "FEATURES" |
212 | Libev supports select, poll, the linux-specific epoll and the bsd-specific |
215 | Libev supports \f(CW\*(C`select\*(C'\fR, \f(CW\*(C`poll\*(C'\fR, the Linux-specific \f(CW\*(C`epoll\*(C'\fR, the |
213 | kqueue mechanisms for file descriptor events, relative timers, absolute |
216 | BSD-specific \f(CW\*(C`kqueue\*(C'\fR and the Solaris-specific event port mechanisms |
214 | timers with customised rescheduling, signal events, process status change |
217 | for file descriptor events (\f(CW\*(C`ev_io\*(C'\fR), the Linux \f(CW\*(C`inotify\*(C'\fR interface |
215 | events (related to \s-1SIGCHLD\s0), and event watchers dealing with the event |
218 | (for \f(CW\*(C`ev_stat\*(C'\fR), relative timers (\f(CW\*(C`ev_timer\*(C'\fR), absolute timers |
216 | loop mechanism itself (idle, prepare and check watchers). It also is quite |
219 | with customised rescheduling (\f(CW\*(C`ev_periodic\*(C'\fR), synchronous signals |
217 | fast (see this benchmark comparing |
220 | (\f(CW\*(C`ev_signal\*(C'\fR), process status change events (\f(CW\*(C`ev_child\*(C'\fR), and event |
218 | it to libevent for example). |
221 | watchers dealing with the event loop mechanism itself (\f(CW\*(C`ev_idle\*(C'\fR, |
|
|
222 | \&\f(CW\*(C`ev_embed\*(C'\fR, \f(CW\*(C`ev_prepare\*(C'\fR and \f(CW\*(C`ev_check\*(C'\fR watchers) as well as |
|
|
223 | file watchers (\f(CW\*(C`ev_stat\*(C'\fR) and even limited support for fork events |
|
|
224 | (\f(CW\*(C`ev_fork\*(C'\fR). |
|
|
225 | .PP |
|
|
226 | It also is quite fast (see this |
|
|
227 | benchmark comparing it to libevent |
|
|
228 | for example). |
219 | .SH "CONVENTIONS" |
229 | .SH "CONVENTIONS" |
220 | .IX Header "CONVENTIONS" |
230 | .IX Header "CONVENTIONS" |
221 | Libev is very configurable. In this manual the default configuration |
231 | Libev is very configurable. In this manual the default configuration will |
222 | will be described, which supports multiple event loops. For more info |
232 | be described, which supports multiple event loops. For more info about |
223 | about various configuration options please have a look at the file |
233 | various configuration options please have a look at \fB\s-1EMBED\s0\fR section in |
224 | \&\fI\s-1README\s0.embed\fR in the libev distribution. If libev was configured without |
234 | this manual. If libev was configured without support for multiple event |
225 | support for multiple event loops, then all functions taking an initial |
235 | loops, then all functions taking an initial argument of name \f(CW\*(C`loop\*(C'\fR |
226 | argument of name \f(CW\*(C`loop\*(C'\fR (which is always of type \f(CW\*(C`struct ev_loop *\*(C'\fR) |
236 | (which is always of type \f(CW\*(C`struct ev_loop *\*(C'\fR) will not have this argument. |
227 | will not have this argument. |
|
|
228 | .SH "TIME REPRESENTATION" |
237 | .SH "TIME REPRESENTATION" |
229 | .IX Header "TIME REPRESENTATION" |
238 | .IX Header "TIME REPRESENTATION" |
230 | Libev represents time as a single floating point number, representing the |
239 | Libev represents time as a single floating point number, representing the |
231 | (fractional) number of seconds since the (\s-1POSIX\s0) epoch (somewhere near |
240 | (fractional) number of seconds since the (\s-1POSIX\s0) epoch (somewhere near |
232 | the beginning of 1970, details are complicated, don't ask). This type is |
241 | the beginning of 1970, details are complicated, don't ask). This type is |
… | |
… | |
257 | Usually, it's a good idea to terminate if the major versions mismatch, |
266 | Usually, it's a good idea to terminate if the major versions mismatch, |
258 | as this indicates an incompatible change. Minor versions are usually |
267 | as this indicates an incompatible change. Minor versions are usually |
259 | compatible to older versions, so a larger minor version alone is usually |
268 | compatible to older versions, so a larger minor version alone is usually |
260 | not a problem. |
269 | not a problem. |
261 | .Sp |
270 | .Sp |
262 | Example: make sure we haven't accidentally been linked against the wrong |
271 | Example: Make sure we haven't accidentally been linked against the wrong |
263 | version: |
272 | version. |
264 | .Sp |
273 | .Sp |
265 | .Vb 3 |
274 | .Vb 3 |
266 | \& assert (("libev version mismatch", |
275 | \& assert (("libev version mismatch", |
267 | \& ev_version_major () == EV_VERSION_MAJOR |
276 | \& ev_version_major () == EV_VERSION_MAJOR |
268 | \& && ev_version_minor () >= EV_VERSION_MINOR)); |
277 | \& && ev_version_minor () >= EV_VERSION_MINOR)); |
… | |
… | |
296 | might be supported on the current system, you would need to look at |
305 | might be supported on the current system, you would need to look at |
297 | \&\f(CW\*(C`ev_embeddable_backends () & ev_supported_backends ()\*(C'\fR, likewise for |
306 | \&\f(CW\*(C`ev_embeddable_backends () & ev_supported_backends ()\*(C'\fR, likewise for |
298 | recommended ones. |
307 | recommended ones. |
299 | .Sp |
308 | .Sp |
300 | See the description of \f(CW\*(C`ev_embed\*(C'\fR watchers for more info. |
309 | See the description of \f(CW\*(C`ev_embed\*(C'\fR watchers for more info. |
301 | .IP "ev_set_allocator (void *(*cb)(void *ptr, size_t size))" 4 |
310 | .IP "ev_set_allocator (void *(*cb)(void *ptr, long size))" 4 |
302 | .IX Item "ev_set_allocator (void *(*cb)(void *ptr, size_t size))" |
311 | .IX Item "ev_set_allocator (void *(*cb)(void *ptr, long size))" |
303 | Sets the allocation function to use (the prototype and semantics are |
312 | Sets the allocation function to use (the prototype is similar \- the |
304 | identical to the realloc C function). It is used to allocate and free |
313 | semantics is identical \- to the realloc C function). It is used to |
305 | memory (no surprises here). If it returns zero when memory needs to be |
314 | allocate and free memory (no surprises here). If it returns zero when |
306 | allocated, the library might abort or take some potentially destructive |
315 | memory needs to be allocated, the library might abort or take some |
307 | action. The default is your system realloc function. |
316 | potentially destructive action. The default is your system realloc |
|
|
317 | function. |
308 | .Sp |
318 | .Sp |
309 | You could override this function in high-availability programs to, say, |
319 | You could override this function in high-availability programs to, say, |
310 | free some memory if it cannot allocate memory, to use a special allocator, |
320 | free some memory if it cannot allocate memory, to use a special allocator, |
311 | or even to sleep a while and retry until some memory is available. |
321 | or even to sleep a while and retry until some memory is available. |
312 | .Sp |
322 | .Sp |
313 | Example: replace the libev allocator with one that waits a bit and then |
323 | Example: Replace the libev allocator with one that waits a bit and then |
314 | retries: better than mine). |
324 | retries). |
315 | .Sp |
325 | .Sp |
316 | .Vb 6 |
326 | .Vb 6 |
317 | \& static void * |
327 | \& static void * |
318 | \& persistent_realloc (void *ptr, size_t size) |
328 | \& persistent_realloc (void *ptr, size_t size) |
319 | \& { |
329 | \& { |
… | |
… | |
345 | callback is set, then libev will expect it to remedy the sitution, no |
355 | callback is set, then libev will expect it to remedy the sitution, no |
346 | matter what, when it returns. That is, libev will generally retry the |
356 | matter what, when it returns. That is, libev will generally retry the |
347 | requested operation, or, if the condition doesn't go away, do bad stuff |
357 | requested operation, or, if the condition doesn't go away, do bad stuff |
348 | (such as abort). |
358 | (such as abort). |
349 | .Sp |
359 | .Sp |
350 | Example: do the same thing as libev does internally: |
360 | Example: This is basically the same thing that libev does internally, too. |
351 | .Sp |
361 | .Sp |
352 | .Vb 6 |
362 | .Vb 6 |
353 | \& static void |
363 | \& static void |
354 | \& fatal_error (const char *msg) |
364 | \& fatal_error (const char *msg) |
355 | \& { |
365 | \& { |
… | |
… | |
401 | or setgid) then libev will \fInot\fR look at the environment variable |
411 | or setgid) then libev will \fInot\fR look at the environment variable |
402 | \&\f(CW\*(C`LIBEV_FLAGS\*(C'\fR. Otherwise (the default), this environment variable will |
412 | \&\f(CW\*(C`LIBEV_FLAGS\*(C'\fR. Otherwise (the default), this environment variable will |
403 | override the flags completely if it is found in the environment. This is |
413 | override the flags completely if it is found in the environment. This is |
404 | useful to try out specific backends to test their performance, or to work |
414 | useful to try out specific backends to test their performance, or to work |
405 | around bugs. |
415 | around bugs. |
|
|
416 | .ie n .IP """EVFLAG_FORKCHECK""" 4 |
|
|
417 | .el .IP "\f(CWEVFLAG_FORKCHECK\fR" 4 |
|
|
418 | .IX Item "EVFLAG_FORKCHECK" |
|
|
419 | Instead of calling \f(CW\*(C`ev_default_fork\*(C'\fR or \f(CW\*(C`ev_loop_fork\*(C'\fR manually after |
|
|
420 | a fork, you can also make libev check for a fork in each iteration by |
|
|
421 | enabling this flag. |
|
|
422 | .Sp |
|
|
423 | This works by calling \f(CW\*(C`getpid ()\*(C'\fR on every iteration of the loop, |
|
|
424 | and thus this might slow down your event loop if you do a lot of loop |
|
|
425 | iterations and little real work, but is usually not noticeable (on my |
|
|
426 | Linux system for example, \f(CW\*(C`getpid\*(C'\fR is actually a simple 5\-insn sequence |
|
|
427 | without a syscall and thus \fIvery\fR fast, but my Linux system also has |
|
|
428 | \&\f(CW\*(C`pthread_atfork\*(C'\fR which is even faster). |
|
|
429 | .Sp |
|
|
430 | The big advantage of this flag is that you can forget about fork (and |
|
|
431 | forget about forgetting to tell libev about forking) when you use this |
|
|
432 | flag. |
|
|
433 | .Sp |
|
|
434 | This flag setting cannot be overriden or specified in the \f(CW\*(C`LIBEV_FLAGS\*(C'\fR |
|
|
435 | environment variable. |
406 | .ie n .IP """EVBACKEND_SELECT"" (value 1, portable select backend)" 4 |
436 | .ie n .IP """EVBACKEND_SELECT"" (value 1, portable select backend)" 4 |
407 | .el .IP "\f(CWEVBACKEND_SELECT\fR (value 1, portable select backend)" 4 |
437 | .el .IP "\f(CWEVBACKEND_SELECT\fR (value 1, portable select backend)" 4 |
408 | .IX Item "EVBACKEND_SELECT (value 1, portable select backend)" |
438 | .IX Item "EVBACKEND_SELECT (value 1, portable select backend)" |
409 | This is your standard \fIselect\fR\|(2) backend. Not \fIcompletely\fR standard, as |
439 | This is your standard \fIselect\fR\|(2) backend. Not \fIcompletely\fR standard, as |
410 | libev tries to roll its own fd_set with no limits on the number of fds, |
440 | libev tries to roll its own fd_set with no limits on the number of fds, |
… | |
… | |
504 | Similar to \f(CW\*(C`ev_default_loop\*(C'\fR, but always creates a new event loop that is |
534 | Similar to \f(CW\*(C`ev_default_loop\*(C'\fR, but always creates a new event loop that is |
505 | always distinct from the default loop. Unlike the default loop, it cannot |
535 | always distinct from the default loop. Unlike the default loop, it cannot |
506 | handle signal and child watchers, and attempts to do so will be greeted by |
536 | handle signal and child watchers, and attempts to do so will be greeted by |
507 | undefined behaviour (or a failed assertion if assertions are enabled). |
537 | undefined behaviour (or a failed assertion if assertions are enabled). |
508 | .Sp |
538 | .Sp |
509 | Example: try to create a event loop that uses epoll and nothing else. |
539 | Example: Try to create a event loop that uses epoll and nothing else. |
510 | .Sp |
540 | .Sp |
511 | .Vb 3 |
541 | .Vb 3 |
512 | \& struct ev_loop *epoller = ev_loop_new (EVBACKEND_EPOLL | EVFLAG_NOENV); |
542 | \& struct ev_loop *epoller = ev_loop_new (EVBACKEND_EPOLL | EVFLAG_NOENV); |
513 | \& if (!epoller) |
543 | \& if (!epoller) |
514 | \& fatal ("no epoll found here, maybe it hides under your chair"); |
544 | \& fatal ("no epoll found here, maybe it hides under your chair"); |
… | |
… | |
551 | .IP "ev_loop_fork (loop)" 4 |
581 | .IP "ev_loop_fork (loop)" 4 |
552 | .IX Item "ev_loop_fork (loop)" |
582 | .IX Item "ev_loop_fork (loop)" |
553 | Like \f(CW\*(C`ev_default_fork\*(C'\fR, but acts on an event loop created by |
583 | Like \f(CW\*(C`ev_default_fork\*(C'\fR, but acts on an event loop created by |
554 | \&\f(CW\*(C`ev_loop_new\*(C'\fR. Yes, you have to call this on every allocated event loop |
584 | \&\f(CW\*(C`ev_loop_new\*(C'\fR. Yes, you have to call this on every allocated event loop |
555 | after fork, and how you do this is entirely your own problem. |
585 | after fork, and how you do this is entirely your own problem. |
|
|
586 | .IP "unsigned int ev_loop_count (loop)" 4 |
|
|
587 | .IX Item "unsigned int ev_loop_count (loop)" |
|
|
588 | Returns the count of loop iterations for the loop, which is identical to |
|
|
589 | the number of times libev did poll for new events. It starts at \f(CW0\fR and |
|
|
590 | happily wraps around with enough iterations. |
|
|
591 | .Sp |
|
|
592 | This value can sometimes be useful as a generation counter of sorts (it |
|
|
593 | \&\*(L"ticks\*(R" the number of loop iterations), as it roughly corresponds with |
|
|
594 | \&\f(CW\*(C`ev_prepare\*(C'\fR and \f(CW\*(C`ev_check\*(C'\fR calls. |
556 | .IP "unsigned int ev_backend (loop)" 4 |
595 | .IP "unsigned int ev_backend (loop)" 4 |
557 | .IX Item "unsigned int ev_backend (loop)" |
596 | .IX Item "unsigned int ev_backend (loop)" |
558 | Returns one of the \f(CW\*(C`EVBACKEND_*\*(C'\fR flags indicating the event backend in |
597 | Returns one of the \f(CW\*(C`EVBACKEND_*\*(C'\fR flags indicating the event backend in |
559 | use. |
598 | use. |
560 | .IP "ev_tstamp ev_now (loop)" 4 |
599 | .IP "ev_tstamp ev_now (loop)" 4 |
… | |
… | |
612 | \& be handled here by queueing them when their watcher gets executed. |
651 | \& be handled here by queueing them when their watcher gets executed. |
613 | \& - If ev_unloop has been called or EVLOOP_ONESHOT or EVLOOP_NONBLOCK |
652 | \& - If ev_unloop has been called or EVLOOP_ONESHOT or EVLOOP_NONBLOCK |
614 | \& were used, return, otherwise continue with step *. |
653 | \& were used, return, otherwise continue with step *. |
615 | .Ve |
654 | .Ve |
616 | .Sp |
655 | .Sp |
617 | Example: queue some jobs and then loop until no events are outsanding |
656 | Example: Queue some jobs and then loop until no events are outsanding |
618 | anymore. |
657 | anymore. |
619 | .Sp |
658 | .Sp |
620 | .Vb 4 |
659 | .Vb 4 |
621 | \& ... queue jobs here, make sure they register event watchers as long |
660 | \& ... queue jobs here, make sure they register event watchers as long |
622 | \& ... as they still have work to do (even an idle watcher will do..) |
661 | \& ... as they still have work to do (even an idle watcher will do..) |
… | |
… | |
644 | visible to the libev user and should not keep \f(CW\*(C`ev_loop\*(C'\fR from exiting if |
683 | visible to the libev user and should not keep \f(CW\*(C`ev_loop\*(C'\fR from exiting if |
645 | no event watchers registered by it are active. It is also an excellent |
684 | no event watchers registered by it are active. It is also an excellent |
646 | way to do this for generic recurring timers or from within third-party |
685 | way to do this for generic recurring timers or from within third-party |
647 | libraries. Just remember to \fIunref after start\fR and \fIref before stop\fR. |
686 | libraries. Just remember to \fIunref after start\fR and \fIref before stop\fR. |
648 | .Sp |
687 | .Sp |
649 | Example: create a signal watcher, but keep it from keeping \f(CW\*(C`ev_loop\*(C'\fR |
688 | Example: Create a signal watcher, but keep it from keeping \f(CW\*(C`ev_loop\*(C'\fR |
650 | running when nothing else is active. |
689 | running when nothing else is active. |
651 | .Sp |
690 | .Sp |
652 | .Vb 4 |
691 | .Vb 4 |
653 | \& struct dv_signal exitsig; |
692 | \& struct ev_signal exitsig; |
654 | \& ev_signal_init (&exitsig, sig_cb, SIGINT); |
693 | \& ev_signal_init (&exitsig, sig_cb, SIGINT); |
655 | \& ev_signal_start (myloop, &exitsig); |
694 | \& ev_signal_start (loop, &exitsig); |
656 | \& evf_unref (myloop); |
695 | \& evf_unref (loop); |
657 | .Ve |
696 | .Ve |
658 | .Sp |
697 | .Sp |
659 | Example: for some weird reason, unregister the above signal handler again. |
698 | Example: For some weird reason, unregister the above signal handler again. |
660 | .Sp |
699 | .Sp |
661 | .Vb 2 |
700 | .Vb 2 |
662 | \& ev_ref (myloop); |
701 | \& ev_ref (loop); |
663 | \& ev_signal_stop (myloop, &exitsig); |
702 | \& ev_signal_stop (loop, &exitsig); |
664 | .Ve |
703 | .Ve |
665 | .SH "ANATOMY OF A WATCHER" |
704 | .SH "ANATOMY OF A WATCHER" |
666 | .IX Header "ANATOMY OF A WATCHER" |
705 | .IX Header "ANATOMY OF A WATCHER" |
667 | A watcher is a structure that you create and register to record your |
706 | A watcher is a structure that you create and register to record your |
668 | interest in some event. For instance, if you want to wait for \s-1STDIN\s0 to |
707 | interest in some event. For instance, if you want to wait for \s-1STDIN\s0 to |
… | |
… | |
848 | Returns a true value iff the watcher is pending, (i.e. it has outstanding |
887 | Returns a true value iff the watcher is pending, (i.e. it has outstanding |
849 | events but its callback has not yet been invoked). As long as a watcher |
888 | events but its callback has not yet been invoked). As long as a watcher |
850 | is pending (but not active) you must not call an init function on it (but |
889 | is pending (but not active) you must not call an init function on it (but |
851 | \&\f(CW\*(C`ev_TYPE_set\*(C'\fR is safe) and you must make sure the watcher is available to |
890 | \&\f(CW\*(C`ev_TYPE_set\*(C'\fR is safe) and you must make sure the watcher is available to |
852 | libev (e.g. you cnanot \f(CW\*(C`free ()\*(C'\fR it). |
891 | libev (e.g. you cnanot \f(CW\*(C`free ()\*(C'\fR it). |
853 | .IP "callback = ev_cb (ev_TYPE *watcher)" 4 |
892 | .IP "callback ev_cb (ev_TYPE *watcher)" 4 |
854 | .IX Item "callback = ev_cb (ev_TYPE *watcher)" |
893 | .IX Item "callback ev_cb (ev_TYPE *watcher)" |
855 | Returns the callback currently set on the watcher. |
894 | Returns the callback currently set on the watcher. |
856 | .IP "ev_cb_set (ev_TYPE *watcher, callback)" 4 |
895 | .IP "ev_cb_set (ev_TYPE *watcher, callback)" 4 |
857 | .IX Item "ev_cb_set (ev_TYPE *watcher, callback)" |
896 | .IX Item "ev_cb_set (ev_TYPE *watcher, callback)" |
858 | Change the callback. You can change the callback at virtually any time |
897 | Change the callback. You can change the callback at virtually any time |
859 | (modulo threads). |
898 | (modulo threads). |
|
|
899 | .IP "ev_set_priority (ev_TYPE *watcher, priority)" 4 |
|
|
900 | .IX Item "ev_set_priority (ev_TYPE *watcher, priority)" |
|
|
901 | .PD 0 |
|
|
902 | .IP "int ev_priority (ev_TYPE *watcher)" 4 |
|
|
903 | .IX Item "int ev_priority (ev_TYPE *watcher)" |
|
|
904 | .PD |
|
|
905 | Set and query the priority of the watcher. The priority is a small |
|
|
906 | integer between \f(CW\*(C`EV_MAXPRI\*(C'\fR (default: \f(CW2\fR) and \f(CW\*(C`EV_MINPRI\*(C'\fR |
|
|
907 | (default: \f(CW\*(C`\-2\*(C'\fR). Pending watchers with higher priority will be invoked |
|
|
908 | before watchers with lower priority, but priority will not keep watchers |
|
|
909 | from being executed (except for \f(CW\*(C`ev_idle\*(C'\fR watchers). |
|
|
910 | .Sp |
|
|
911 | This means that priorities are \fIonly\fR used for ordering callback |
|
|
912 | invocation after new events have been received. This is useful, for |
|
|
913 | example, to reduce latency after idling, or more often, to bind two |
|
|
914 | watchers on the same event and make sure one is called first. |
|
|
915 | .Sp |
|
|
916 | If you need to suppress invocation when higher priority events are pending |
|
|
917 | you need to look at \f(CW\*(C`ev_idle\*(C'\fR watchers, which provide this functionality. |
|
|
918 | .Sp |
|
|
919 | The default priority used by watchers when no priority has been set is |
|
|
920 | always \f(CW0\fR, which is supposed to not be too high and not be too low :). |
|
|
921 | .Sp |
|
|
922 | Setting a priority outside the range of \f(CW\*(C`EV_MINPRI\*(C'\fR to \f(CW\*(C`EV_MAXPRI\*(C'\fR is |
|
|
923 | fine, as long as you do not mind that the priority value you query might |
|
|
924 | or might not have been adjusted to be within valid range. |
860 | .Sh "\s-1ASSOCIATING\s0 \s-1CUSTOM\s0 \s-1DATA\s0 \s-1WITH\s0 A \s-1WATCHER\s0" |
925 | .Sh "\s-1ASSOCIATING\s0 \s-1CUSTOM\s0 \s-1DATA\s0 \s-1WITH\s0 A \s-1WATCHER\s0" |
861 | .IX Subsection "ASSOCIATING CUSTOM DATA WITH A WATCHER" |
926 | .IX Subsection "ASSOCIATING CUSTOM DATA WITH A WATCHER" |
862 | Each watcher has, by default, a member \f(CW\*(C`void *data\*(C'\fR that you can change |
927 | Each watcher has, by default, a member \f(CW\*(C`void *data\*(C'\fR that you can change |
863 | and read at any time, libev will completely ignore it. This can be used |
928 | and read at any time, libev will completely ignore it. This can be used |
864 | to associate arbitrary data with your watcher. If you need more data and |
929 | to associate arbitrary data with your watcher. If you need more data and |
… | |
… | |
885 | \& struct my_io *w = (struct my_io *)w_; |
950 | \& struct my_io *w = (struct my_io *)w_; |
886 | \& ... |
951 | \& ... |
887 | \& } |
952 | \& } |
888 | .Ve |
953 | .Ve |
889 | .PP |
954 | .PP |
890 | More interesting and less C\-conformant ways of catsing your callback type |
955 | More interesting and less C\-conformant ways of casting your callback type |
891 | have been omitted.... |
956 | instead have been omitted. |
|
|
957 | .PP |
|
|
958 | Another common scenario is having some data structure with multiple |
|
|
959 | watchers: |
|
|
960 | .PP |
|
|
961 | .Vb 6 |
|
|
962 | \& struct my_biggy |
|
|
963 | \& { |
|
|
964 | \& int some_data; |
|
|
965 | \& ev_timer t1; |
|
|
966 | \& ev_timer t2; |
|
|
967 | \& } |
|
|
968 | .Ve |
|
|
969 | .PP |
|
|
970 | In this case getting the pointer to \f(CW\*(C`my_biggy\*(C'\fR is a bit more complicated, |
|
|
971 | you need to use \f(CW\*(C`offsetof\*(C'\fR: |
|
|
972 | .PP |
|
|
973 | .Vb 1 |
|
|
974 | \& #include <stddef.h> |
|
|
975 | .Ve |
|
|
976 | .PP |
|
|
977 | .Vb 6 |
|
|
978 | \& static void |
|
|
979 | \& t1_cb (EV_P_ struct ev_timer *w, int revents) |
|
|
980 | \& { |
|
|
981 | \& struct my_biggy big = (struct my_biggy * |
|
|
982 | \& (((char *)w) - offsetof (struct my_biggy, t1)); |
|
|
983 | \& } |
|
|
984 | .Ve |
|
|
985 | .PP |
|
|
986 | .Vb 6 |
|
|
987 | \& static void |
|
|
988 | \& t2_cb (EV_P_ struct ev_timer *w, int revents) |
|
|
989 | \& { |
|
|
990 | \& struct my_biggy big = (struct my_biggy * |
|
|
991 | \& (((char *)w) - offsetof (struct my_biggy, t2)); |
|
|
992 | \& } |
|
|
993 | .Ve |
892 | .SH "WATCHER TYPES" |
994 | .SH "WATCHER TYPES" |
893 | .IX Header "WATCHER TYPES" |
995 | .IX Header "WATCHER TYPES" |
894 | This section describes each watcher in detail, but will not repeat |
996 | This section describes each watcher in detail, but will not repeat |
895 | information given in the last section. Any initialisation/set macros, |
997 | information given in the last section. Any initialisation/set macros, |
896 | functions and members specific to the watcher type are explained. |
998 | functions and members specific to the watcher type are explained. |
… | |
… | |
957 | The file descriptor being watched. |
1059 | The file descriptor being watched. |
958 | .IP "int events [read\-only]" 4 |
1060 | .IP "int events [read\-only]" 4 |
959 | .IX Item "int events [read-only]" |
1061 | .IX Item "int events [read-only]" |
960 | The events being watched. |
1062 | The events being watched. |
961 | .PP |
1063 | .PP |
962 | Example: call \f(CW\*(C`stdin_readable_cb\*(C'\fR when \s-1STDIN_FILENO\s0 has become, well |
1064 | Example: Call \f(CW\*(C`stdin_readable_cb\*(C'\fR when \s-1STDIN_FILENO\s0 has become, well |
963 | readable, but only once. Since it is likely line\-buffered, you could |
1065 | readable, but only once. Since it is likely line\-buffered, you could |
964 | attempt to read a whole line in the callback: |
1066 | attempt to read a whole line in the callback. |
965 | .PP |
1067 | .PP |
966 | .Vb 6 |
1068 | .Vb 6 |
967 | \& static void |
1069 | \& static void |
968 | \& stdin_readable_cb (struct ev_loop *loop, struct ev_io *w, int revents) |
1070 | \& stdin_readable_cb (struct ev_loop *loop, struct ev_io *w, int revents) |
969 | \& { |
1071 | \& { |
… | |
… | |
1024 | .IP "ev_timer_again (loop)" 4 |
1126 | .IP "ev_timer_again (loop)" 4 |
1025 | .IX Item "ev_timer_again (loop)" |
1127 | .IX Item "ev_timer_again (loop)" |
1026 | This will act as if the timer timed out and restart it again if it is |
1128 | This will act as if the timer timed out and restart it again if it is |
1027 | repeating. The exact semantics are: |
1129 | repeating. The exact semantics are: |
1028 | .Sp |
1130 | .Sp |
|
|
1131 | If the timer is pending, its pending status is cleared. |
|
|
1132 | .Sp |
1029 | If the timer is started but nonrepeating, stop it. |
1133 | If the timer is started but nonrepeating, stop it (as if it timed out). |
1030 | .Sp |
1134 | .Sp |
1031 | If the timer is repeating, either start it if necessary (with the repeat |
1135 | If the timer is repeating, either start it if necessary (with the |
1032 | value), or reset the running timer to the repeat value. |
1136 | \&\f(CW\*(C`repeat\*(C'\fR value), or reset the running timer to the \f(CW\*(C`repeat\*(C'\fR value. |
1033 | .Sp |
1137 | .Sp |
1034 | This sounds a bit complicated, but here is a useful and typical |
1138 | This sounds a bit complicated, but here is a useful and typical |
1035 | example: Imagine you have a tcp connection and you want a so-called |
1139 | example: Imagine you have a tcp connection and you want a so-called idle |
1036 | idle timeout, that is, you want to be called when there have been, |
1140 | timeout, that is, you want to be called when there have been, say, 60 |
1037 | say, 60 seconds of inactivity on the socket. The easiest way to do |
1141 | seconds of inactivity on the socket. The easiest way to do this is to |
1038 | this is to configure an \f(CW\*(C`ev_timer\*(C'\fR with \f(CW\*(C`after\*(C'\fR=\f(CW\*(C`repeat\*(C'\fR=\f(CW60\fR and calling |
1142 | configure an \f(CW\*(C`ev_timer\*(C'\fR with a \f(CW\*(C`repeat\*(C'\fR value of \f(CW60\fR and then call |
1039 | \&\f(CW\*(C`ev_timer_again\*(C'\fR each time you successfully read or write some data. If |
1143 | \&\f(CW\*(C`ev_timer_again\*(C'\fR each time you successfully read or write some data. If |
1040 | you go into an idle state where you do not expect data to travel on the |
1144 | you go into an idle state where you do not expect data to travel on the |
1041 | socket, you can stop the timer, and again will automatically restart it if |
1145 | socket, you can \f(CW\*(C`ev_timer_stop\*(C'\fR the timer, and \f(CW\*(C`ev_timer_again\*(C'\fR will |
1042 | need be. |
1146 | automatically restart it if need be. |
1043 | .Sp |
1147 | .Sp |
1044 | You can also ignore the \f(CW\*(C`after\*(C'\fR value and \f(CW\*(C`ev_timer_start\*(C'\fR altogether |
1148 | That means you can ignore the \f(CW\*(C`after\*(C'\fR value and \f(CW\*(C`ev_timer_start\*(C'\fR |
1045 | and only ever use the \f(CW\*(C`repeat\*(C'\fR value: |
1149 | altogether and only ever use the \f(CW\*(C`repeat\*(C'\fR value and \f(CW\*(C`ev_timer_again\*(C'\fR: |
1046 | .Sp |
1150 | .Sp |
1047 | .Vb 8 |
1151 | .Vb 8 |
1048 | \& ev_timer_init (timer, callback, 0., 5.); |
1152 | \& ev_timer_init (timer, callback, 0., 5.); |
1049 | \& ev_timer_again (loop, timer); |
1153 | \& ev_timer_again (loop, timer); |
1050 | \& ... |
1154 | \& ... |
… | |
… | |
1053 | \& ... |
1157 | \& ... |
1054 | \& timer->again = 10.; |
1158 | \& timer->again = 10.; |
1055 | \& ev_timer_again (loop, timer); |
1159 | \& ev_timer_again (loop, timer); |
1056 | .Ve |
1160 | .Ve |
1057 | .Sp |
1161 | .Sp |
1058 | This is more efficient then stopping/starting the timer eahc time you want |
1162 | This is more slightly efficient then stopping/starting the timer each time |
1059 | to modify its timeout value. |
1163 | you want to modify its timeout value. |
1060 | .IP "ev_tstamp repeat [read\-write]" 4 |
1164 | .IP "ev_tstamp repeat [read\-write]" 4 |
1061 | .IX Item "ev_tstamp repeat [read-write]" |
1165 | .IX Item "ev_tstamp repeat [read-write]" |
1062 | The current \f(CW\*(C`repeat\*(C'\fR value. Will be used each time the watcher times out |
1166 | The current \f(CW\*(C`repeat\*(C'\fR value. Will be used each time the watcher times out |
1063 | or \f(CW\*(C`ev_timer_again\*(C'\fR is called and determines the next timeout (if any), |
1167 | or \f(CW\*(C`ev_timer_again\*(C'\fR is called and determines the next timeout (if any), |
1064 | which is also when any modifications are taken into account. |
1168 | which is also when any modifications are taken into account. |
1065 | .PP |
1169 | .PP |
1066 | Example: create a timer that fires after 60 seconds. |
1170 | Example: Create a timer that fires after 60 seconds. |
1067 | .PP |
1171 | .PP |
1068 | .Vb 5 |
1172 | .Vb 5 |
1069 | \& static void |
1173 | \& static void |
1070 | \& one_minute_cb (struct ev_loop *loop, struct ev_timer *w, int revents) |
1174 | \& one_minute_cb (struct ev_loop *loop, struct ev_timer *w, int revents) |
1071 | \& { |
1175 | \& { |
… | |
… | |
1077 | \& struct ev_timer mytimer; |
1181 | \& struct ev_timer mytimer; |
1078 | \& ev_timer_init (&mytimer, one_minute_cb, 60., 0.); |
1182 | \& ev_timer_init (&mytimer, one_minute_cb, 60., 0.); |
1079 | \& ev_timer_start (loop, &mytimer); |
1183 | \& ev_timer_start (loop, &mytimer); |
1080 | .Ve |
1184 | .Ve |
1081 | .PP |
1185 | .PP |
1082 | Example: create a timeout timer that times out after 10 seconds of |
1186 | Example: Create a timeout timer that times out after 10 seconds of |
1083 | inactivity. |
1187 | inactivity. |
1084 | .PP |
1188 | .PP |
1085 | .Vb 5 |
1189 | .Vb 5 |
1086 | \& static void |
1190 | \& static void |
1087 | \& timeout_cb (struct ev_loop *loop, struct ev_timer *w, int revents) |
1191 | \& timeout_cb (struct ev_loop *loop, struct ev_timer *w, int revents) |
… | |
… | |
1212 | .IX Item "ev_tstamp (*reschedule_cb)(struct ev_periodic *w, ev_tstamp now) [read-write]" |
1316 | .IX Item "ev_tstamp (*reschedule_cb)(struct ev_periodic *w, ev_tstamp now) [read-write]" |
1213 | The current reschedule callback, or \f(CW0\fR, if this functionality is |
1317 | The current reschedule callback, or \f(CW0\fR, if this functionality is |
1214 | switched off. Can be changed any time, but changes only take effect when |
1318 | switched off. Can be changed any time, but changes only take effect when |
1215 | the periodic timer fires or \f(CW\*(C`ev_periodic_again\*(C'\fR is being called. |
1319 | the periodic timer fires or \f(CW\*(C`ev_periodic_again\*(C'\fR is being called. |
1216 | .PP |
1320 | .PP |
1217 | Example: call a callback every hour, or, more precisely, whenever the |
1321 | Example: Call a callback every hour, or, more precisely, whenever the |
1218 | system clock is divisible by 3600. The callback invocation times have |
1322 | system clock is divisible by 3600. The callback invocation times have |
1219 | potentially a lot of jittering, but good long-term stability. |
1323 | potentially a lot of jittering, but good long-term stability. |
1220 | .PP |
1324 | .PP |
1221 | .Vb 5 |
1325 | .Vb 5 |
1222 | \& static void |
1326 | \& static void |
… | |
… | |
1230 | \& struct ev_periodic hourly_tick; |
1334 | \& struct ev_periodic hourly_tick; |
1231 | \& ev_periodic_init (&hourly_tick, clock_cb, 0., 3600., 0); |
1335 | \& ev_periodic_init (&hourly_tick, clock_cb, 0., 3600., 0); |
1232 | \& ev_periodic_start (loop, &hourly_tick); |
1336 | \& ev_periodic_start (loop, &hourly_tick); |
1233 | .Ve |
1337 | .Ve |
1234 | .PP |
1338 | .PP |
1235 | Example: the same as above, but use a reschedule callback to do it: |
1339 | Example: The same as above, but use a reschedule callback to do it: |
1236 | .PP |
1340 | .PP |
1237 | .Vb 1 |
1341 | .Vb 1 |
1238 | \& #include <math.h> |
1342 | \& #include <math.h> |
1239 | .Ve |
1343 | .Ve |
1240 | .PP |
1344 | .PP |
… | |
… | |
1248 | .PP |
1352 | .PP |
1249 | .Vb 1 |
1353 | .Vb 1 |
1250 | \& ev_periodic_init (&hourly_tick, clock_cb, 0., 0., my_scheduler_cb); |
1354 | \& ev_periodic_init (&hourly_tick, clock_cb, 0., 0., my_scheduler_cb); |
1251 | .Ve |
1355 | .Ve |
1252 | .PP |
1356 | .PP |
1253 | Example: call a callback every hour, starting now: |
1357 | Example: Call a callback every hour, starting now: |
1254 | .PP |
1358 | .PP |
1255 | .Vb 4 |
1359 | .Vb 4 |
1256 | \& struct ev_periodic hourly_tick; |
1360 | \& struct ev_periodic hourly_tick; |
1257 | \& ev_periodic_init (&hourly_tick, clock_cb, |
1361 | \& ev_periodic_init (&hourly_tick, clock_cb, |
1258 | \& fmod (ev_now (loop), 3600.), 3600., 0); |
1362 | \& fmod (ev_now (loop), 3600.), 3600., 0); |
… | |
… | |
1309 | .IP "int rstatus [read\-write]" 4 |
1413 | .IP "int rstatus [read\-write]" 4 |
1310 | .IX Item "int rstatus [read-write]" |
1414 | .IX Item "int rstatus [read-write]" |
1311 | The process exit/trace status caused by \f(CW\*(C`rpid\*(C'\fR (see your systems |
1415 | The process exit/trace status caused by \f(CW\*(C`rpid\*(C'\fR (see your systems |
1312 | \&\f(CW\*(C`waitpid\*(C'\fR and \f(CW\*(C`sys/wait.h\*(C'\fR documentation for details). |
1416 | \&\f(CW\*(C`waitpid\*(C'\fR and \f(CW\*(C`sys/wait.h\*(C'\fR documentation for details). |
1313 | .PP |
1417 | .PP |
1314 | Example: try to exit cleanly on \s-1SIGINT\s0 and \s-1SIGTERM\s0. |
1418 | Example: Try to exit cleanly on \s-1SIGINT\s0 and \s-1SIGTERM\s0. |
1315 | .PP |
1419 | .PP |
1316 | .Vb 5 |
1420 | .Vb 5 |
1317 | \& static void |
1421 | \& static void |
1318 | \& sigint_cb (struct ev_loop *loop, struct ev_signal *w, int revents) |
1422 | \& sigint_cb (struct ev_loop *loop, struct ev_signal *w, int revents) |
1319 | \& { |
1423 | \& { |
… | |
… | |
1337 | not exist\*(R" is a status change like any other. The condition \*(L"path does |
1441 | not exist\*(R" is a status change like any other. The condition \*(L"path does |
1338 | not exist\*(R" is signified by the \f(CW\*(C`st_nlink\*(C'\fR field being zero (which is |
1442 | not exist\*(R" is signified by the \f(CW\*(C`st_nlink\*(C'\fR field being zero (which is |
1339 | otherwise always forced to be at least one) and all the other fields of |
1443 | otherwise always forced to be at least one) and all the other fields of |
1340 | the stat buffer having unspecified contents. |
1444 | the stat buffer having unspecified contents. |
1341 | .PP |
1445 | .PP |
|
|
1446 | The path \fIshould\fR be absolute and \fImust not\fR end in a slash. If it is |
|
|
1447 | relative and your working directory changes, the behaviour is undefined. |
|
|
1448 | .PP |
1342 | Since there is no standard to do this, the portable implementation simply |
1449 | Since there is no standard to do this, the portable implementation simply |
1343 | calls \f(CW\*(C`stat (2)\*(C'\fR regulalry on the path to see if it changed somehow. You |
1450 | calls \f(CW\*(C`stat (2)\*(C'\fR regularly on the path to see if it changed somehow. You |
1344 | can specify a recommended polling interval for this case. If you specify |
1451 | can specify a recommended polling interval for this case. If you specify |
1345 | a polling interval of \f(CW0\fR (highly recommended!) then a \fIsuitable, |
1452 | a polling interval of \f(CW0\fR (highly recommended!) then a \fIsuitable, |
1346 | unspecified default\fR value will be used (which you can expect to be around |
1453 | unspecified default\fR value will be used (which you can expect to be around |
1347 | five seconds, although this might change dynamically). Libev will also |
1454 | five seconds, although this might change dynamically). Libev will also |
1348 | impose a minimum interval which is currently around \f(CW0.1\fR, but thats |
1455 | impose a minimum interval which is currently around \f(CW0.1\fR, but thats |
… | |
… | |
1350 | .PP |
1457 | .PP |
1351 | This watcher type is not meant for massive numbers of stat watchers, |
1458 | This watcher type is not meant for massive numbers of stat watchers, |
1352 | as even with OS-supported change notifications, this can be |
1459 | as even with OS-supported change notifications, this can be |
1353 | resource\-intensive. |
1460 | resource\-intensive. |
1354 | .PP |
1461 | .PP |
1355 | At the time of this writing, no specific \s-1OS\s0 backends are implemented, but |
1462 | At the time of this writing, only the Linux inotify interface is |
1356 | if demand increases, at least a kqueue and inotify backend will be added. |
1463 | implemented (implementing kqueue support is left as an exercise for the |
|
|
1464 | reader). Inotify will be used to give hints only and should not change the |
|
|
1465 | semantics of \f(CW\*(C`ev_stat\*(C'\fR watchers, which means that libev sometimes needs |
|
|
1466 | to fall back to regular polling again even with inotify, but changes are |
|
|
1467 | usually detected immediately, and if the file exists there will be no |
|
|
1468 | polling. |
1357 | .IP "ev_stat_init (ev_stat *, callback, const char *path, ev_tstamp interval)" 4 |
1469 | .IP "ev_stat_init (ev_stat *, callback, const char *path, ev_tstamp interval)" 4 |
1358 | .IX Item "ev_stat_init (ev_stat *, callback, const char *path, ev_tstamp interval)" |
1470 | .IX Item "ev_stat_init (ev_stat *, callback, const char *path, ev_tstamp interval)" |
1359 | .PD 0 |
1471 | .PD 0 |
1360 | .IP "ev_stat_set (ev_stat *, const char *path, ev_tstamp interval)" 4 |
1472 | .IP "ev_stat_set (ev_stat *, const char *path, ev_tstamp interval)" 4 |
1361 | .IX Item "ev_stat_set (ev_stat *, const char *path, ev_tstamp interval)" |
1473 | .IX Item "ev_stat_set (ev_stat *, const char *path, ev_tstamp interval)" |
… | |
… | |
1422 | \& ev_stat_start (loop, &passwd); |
1534 | \& ev_stat_start (loop, &passwd); |
1423 | .Ve |
1535 | .Ve |
1424 | .ie n .Sh """ev_idle"" \- when you've got nothing better to do..." |
1536 | .ie n .Sh """ev_idle"" \- when you've got nothing better to do..." |
1425 | .el .Sh "\f(CWev_idle\fP \- when you've got nothing better to do..." |
1537 | .el .Sh "\f(CWev_idle\fP \- when you've got nothing better to do..." |
1426 | .IX Subsection "ev_idle - when you've got nothing better to do..." |
1538 | .IX Subsection "ev_idle - when you've got nothing better to do..." |
1427 | Idle watchers trigger events when there are no other events are pending |
1539 | Idle watchers trigger events when no other events of the same or higher |
1428 | (prepare, check and other idle watchers do not count). That is, as long |
1540 | priority are pending (prepare, check and other idle watchers do not |
1429 | as your process is busy handling sockets or timeouts (or even signals, |
1541 | count). |
1430 | imagine) it will not be triggered. But when your process is idle all idle |
1542 | .PP |
1431 | watchers are being called again and again, once per event loop iteration \- |
1543 | That is, as long as your process is busy handling sockets or timeouts |
|
|
1544 | (or even signals, imagine) of the same or higher priority it will not be |
|
|
1545 | triggered. But when your process is idle (or only lower-priority watchers |
|
|
1546 | are pending), the idle watchers are being called once per event loop |
1432 | until stopped, that is, or your process receives more events and becomes |
1547 | iteration \- until stopped, that is, or your process receives more events |
1433 | busy. |
1548 | and becomes busy again with higher priority stuff. |
1434 | .PP |
1549 | .PP |
1435 | The most noteworthy effect is that as long as any idle watchers are |
1550 | The most noteworthy effect is that as long as any idle watchers are |
1436 | active, the process will not block when waiting for new events. |
1551 | active, the process will not block when waiting for new events. |
1437 | .PP |
1552 | .PP |
1438 | Apart from keeping your process non-blocking (which is a useful |
1553 | Apart from keeping your process non-blocking (which is a useful |
… | |
… | |
1443 | .IX Item "ev_idle_init (ev_signal *, callback)" |
1558 | .IX Item "ev_idle_init (ev_signal *, callback)" |
1444 | Initialises and configures the idle watcher \- it has no parameters of any |
1559 | Initialises and configures the idle watcher \- it has no parameters of any |
1445 | kind. There is a \f(CW\*(C`ev_idle_set\*(C'\fR macro, but using it is utterly pointless, |
1560 | kind. There is a \f(CW\*(C`ev_idle_set\*(C'\fR macro, but using it is utterly pointless, |
1446 | believe me. |
1561 | believe me. |
1447 | .PP |
1562 | .PP |
1448 | Example: dynamically allocate an \f(CW\*(C`ev_idle\*(C'\fR, start it, and in the |
1563 | Example: Dynamically allocate an \f(CW\*(C`ev_idle\*(C'\fR watcher, start it, and in the |
1449 | callback, free it. Alos, use no error checking, as usual. |
1564 | callback, free it. Also, use no error checking, as usual. |
1450 | .PP |
1565 | .PP |
1451 | .Vb 7 |
1566 | .Vb 7 |
1452 | \& static void |
1567 | \& static void |
1453 | \& idle_cb (struct ev_loop *loop, struct ev_idle *w, int revents) |
1568 | \& idle_cb (struct ev_loop *loop, struct ev_idle *w, int revents) |
1454 | \& { |
1569 | \& { |
… | |
… | |
1533 | \& if (revents & EV_READ ) fd->revents |= fd->events & POLLIN; |
1648 | \& if (revents & EV_READ ) fd->revents |= fd->events & POLLIN; |
1534 | \& if (revents & EV_WRITE) fd->revents |= fd->events & POLLOUT; |
1649 | \& if (revents & EV_WRITE) fd->revents |= fd->events & POLLOUT; |
1535 | \& } |
1650 | \& } |
1536 | .Ve |
1651 | .Ve |
1537 | .PP |
1652 | .PP |
1538 | .Vb 7 |
1653 | .Vb 8 |
1539 | \& // create io watchers for each fd and a timer before blocking |
1654 | \& // create io watchers for each fd and a timer before blocking |
1540 | \& static void |
1655 | \& static void |
1541 | \& adns_prepare_cb (ev_loop *loop, ev_prepare *w, int revents) |
1656 | \& adns_prepare_cb (ev_loop *loop, ev_prepare *w, int revents) |
1542 | \& { |
1657 | \& { |
1543 | \& int timeout = 3600000;truct pollfd fds [nfd]; |
1658 | \& int timeout = 3600000; |
|
|
1659 | \& struct pollfd fds [nfd]; |
1544 | \& // actual code will need to loop here and realloc etc. |
1660 | \& // actual code will need to loop here and realloc etc. |
1545 | \& adns_beforepoll (ads, fds, &nfd, &timeout, timeval_from (ev_time ())); |
1661 | \& adns_beforepoll (ads, fds, &nfd, &timeout, timeval_from (ev_time ())); |
1546 | .Ve |
1662 | .Ve |
1547 | .PP |
1663 | .PP |
1548 | .Vb 3 |
1664 | .Vb 3 |
… | |
… | |
1920 | .el .IP "\f(CWEV_DEFAULT\fR, \f(CWEV_DEFAULT_\fR" 4 |
2036 | .el .IP "\f(CWEV_DEFAULT\fR, \f(CWEV_DEFAULT_\fR" 4 |
1921 | .IX Item "EV_DEFAULT, EV_DEFAULT_" |
2037 | .IX Item "EV_DEFAULT, EV_DEFAULT_" |
1922 | Similar to the other two macros, this gives you the value of the default |
2038 | Similar to the other two macros, this gives you the value of the default |
1923 | loop, if multiple loops are supported (\*(L"ev loop default\*(R"). |
2039 | loop, if multiple loops are supported (\*(L"ev loop default\*(R"). |
1924 | .PP |
2040 | .PP |
1925 | Example: Declare and initialise a check watcher, working regardless of |
2041 | Example: Declare and initialise a check watcher, utilising the above |
1926 | wether multiple loops are supported or not. |
2042 | macros so it will work regardless of wether multiple loops are supported |
|
|
2043 | or not. |
1927 | .PP |
2044 | .PP |
1928 | .Vb 5 |
2045 | .Vb 5 |
1929 | \& static void |
2046 | \& static void |
1930 | \& check_cb (EV_P_ ev_timer *w, int revents) |
2047 | \& check_cb (EV_P_ ev_timer *w, int revents) |
1931 | \& { |
2048 | \& { |
… | |
… | |
1994 | .Vb 1 |
2111 | .Vb 1 |
1995 | \& ev_win32.c required on win32 platforms only |
2112 | \& ev_win32.c required on win32 platforms only |
1996 | .Ve |
2113 | .Ve |
1997 | .PP |
2114 | .PP |
1998 | .Vb 5 |
2115 | .Vb 5 |
1999 | \& ev_select.c only when select backend is enabled (which is by default) |
2116 | \& ev_select.c only when select backend is enabled (which is enabled by default) |
2000 | \& ev_poll.c only when poll backend is enabled (disabled by default) |
2117 | \& ev_poll.c only when poll backend is enabled (disabled by default) |
2001 | \& ev_epoll.c only when the epoll backend is enabled (disabled by default) |
2118 | \& ev_epoll.c only when the epoll backend is enabled (disabled by default) |
2002 | \& ev_kqueue.c only when the kqueue backend is enabled (disabled by default) |
2119 | \& ev_kqueue.c only when the kqueue backend is enabled (disabled by default) |
2003 | \& ev_port.c only when the solaris port backend is enabled (disabled by default) |
2120 | \& ev_port.c only when the solaris port backend is enabled (disabled by default) |
2004 | .Ve |
2121 | .Ve |
… | |
… | |
2125 | otherwise another method will be used as fallback. This is the preferred |
2242 | otherwise another method will be used as fallback. This is the preferred |
2126 | backend for Solaris 10 systems. |
2243 | backend for Solaris 10 systems. |
2127 | .IP "\s-1EV_USE_DEVPOLL\s0" 4 |
2244 | .IP "\s-1EV_USE_DEVPOLL\s0" 4 |
2128 | .IX Item "EV_USE_DEVPOLL" |
2245 | .IX Item "EV_USE_DEVPOLL" |
2129 | reserved for future expansion, works like the \s-1USE\s0 symbols above. |
2246 | reserved for future expansion, works like the \s-1USE\s0 symbols above. |
|
|
2247 | .IP "\s-1EV_USE_INOTIFY\s0" 4 |
|
|
2248 | .IX Item "EV_USE_INOTIFY" |
|
|
2249 | If defined to be \f(CW1\fR, libev will compile in support for the Linux inotify |
|
|
2250 | interface to speed up \f(CW\*(C`ev_stat\*(C'\fR watchers. Its actual availability will |
|
|
2251 | be detected at runtime. |
2130 | .IP "\s-1EV_H\s0" 4 |
2252 | .IP "\s-1EV_H\s0" 4 |
2131 | .IX Item "EV_H" |
2253 | .IX Item "EV_H" |
2132 | The name of the \fIev.h\fR header file used to include it. The default if |
2254 | The name of the \fIev.h\fR header file used to include it. The default if |
2133 | undefined is \f(CW\*(C`<ev.h>\*(C'\fR in \fIevent.h\fR and \f(CW"ev.h"\fR in \fIev.c\fR. This |
2255 | undefined is \f(CW\*(C`<ev.h>\*(C'\fR in \fIevent.h\fR and \f(CW"ev.h"\fR in \fIev.c\fR. This |
2134 | can be used to virtually rename the \fIev.h\fR header file in case of conflicts. |
2256 | can be used to virtually rename the \fIev.h\fR header file in case of conflicts. |
… | |
… | |
2157 | .IP "\s-1EV_PERIODIC_ENABLE\s0" 4 |
2279 | .IP "\s-1EV_PERIODIC_ENABLE\s0" 4 |
2158 | .IX Item "EV_PERIODIC_ENABLE" |
2280 | .IX Item "EV_PERIODIC_ENABLE" |
2159 | If undefined or defined to be \f(CW1\fR, then periodic timers are supported. If |
2281 | If undefined or defined to be \f(CW1\fR, then periodic timers are supported. If |
2160 | defined to be \f(CW0\fR, then they are not. Disabling them saves a few kB of |
2282 | defined to be \f(CW0\fR, then they are not. Disabling them saves a few kB of |
2161 | code. |
2283 | code. |
|
|
2284 | .IP "\s-1EV_IDLE_ENABLE\s0" 4 |
|
|
2285 | .IX Item "EV_IDLE_ENABLE" |
|
|
2286 | If undefined or defined to be \f(CW1\fR, then idle watchers are supported. If |
|
|
2287 | defined to be \f(CW0\fR, then they are not. Disabling them saves a few kB of |
|
|
2288 | code. |
2162 | .IP "\s-1EV_EMBED_ENABLE\s0" 4 |
2289 | .IP "\s-1EV_EMBED_ENABLE\s0" 4 |
2163 | .IX Item "EV_EMBED_ENABLE" |
2290 | .IX Item "EV_EMBED_ENABLE" |
2164 | If undefined or defined to be \f(CW1\fR, then embed watchers are supported. If |
2291 | If undefined or defined to be \f(CW1\fR, then embed watchers are supported. If |
2165 | defined to be \f(CW0\fR, then they are not. |
2292 | defined to be \f(CW0\fR, then they are not. |
2166 | .IP "\s-1EV_STAT_ENABLE\s0" 4 |
2293 | .IP "\s-1EV_STAT_ENABLE\s0" 4 |
… | |
… | |
2179 | .IP "\s-1EV_PID_HASHSIZE\s0" 4 |
2306 | .IP "\s-1EV_PID_HASHSIZE\s0" 4 |
2180 | .IX Item "EV_PID_HASHSIZE" |
2307 | .IX Item "EV_PID_HASHSIZE" |
2181 | \&\f(CW\*(C`ev_child\*(C'\fR watchers use a small hash table to distribute workload by |
2308 | \&\f(CW\*(C`ev_child\*(C'\fR watchers use a small hash table to distribute workload by |
2182 | pid. The default size is \f(CW16\fR (or \f(CW1\fR with \f(CW\*(C`EV_MINIMAL\*(C'\fR), usually more |
2309 | pid. The default size is \f(CW16\fR (or \f(CW1\fR with \f(CW\*(C`EV_MINIMAL\*(C'\fR), usually more |
2183 | than enough. If you need to manage thousands of children you might want to |
2310 | than enough. If you need to manage thousands of children you might want to |
2184 | increase this value. |
2311 | increase this value (\fImust\fR be a power of two). |
|
|
2312 | .IP "\s-1EV_INOTIFY_HASHSIZE\s0" 4 |
|
|
2313 | .IX Item "EV_INOTIFY_HASHSIZE" |
|
|
2314 | \&\f(CW\*(C`ev_staz\*(C'\fR watchers use a small hash table to distribute workload by |
|
|
2315 | inotify watch id. The default size is \f(CW16\fR (or \f(CW1\fR with \f(CW\*(C`EV_MINIMAL\*(C'\fR), |
|
|
2316 | usually more than enough. If you need to manage thousands of \f(CW\*(C`ev_stat\*(C'\fR |
|
|
2317 | watchers you might want to increase this value (\fImust\fR be a power of |
|
|
2318 | two). |
2185 | .IP "\s-1EV_COMMON\s0" 4 |
2319 | .IP "\s-1EV_COMMON\s0" 4 |
2186 | .IX Item "EV_COMMON" |
2320 | .IX Item "EV_COMMON" |
2187 | By default, all watchers have a \f(CW\*(C`void *data\*(C'\fR member. By redefining |
2321 | By default, all watchers have a \f(CW\*(C`void *data\*(C'\fR member. By redefining |
2188 | this macro to a something else you can include more and other types of |
2322 | this macro to a something else you can include more and other types of |
2189 | members. You have to define it each time you include one of the files, |
2323 | members. You have to define it each time you include one of the files, |
… | |
… | |
2219 | interface) and \fI\s-1EV\s0.xs\fR (implementation) files. Only the \fI\s-1EV\s0.xs\fR file |
2353 | interface) and \fI\s-1EV\s0.xs\fR (implementation) files. Only the \fI\s-1EV\s0.xs\fR file |
2220 | will be compiled. It is pretty complex because it provides its own header |
2354 | will be compiled. It is pretty complex because it provides its own header |
2221 | file. |
2355 | file. |
2222 | .Sp |
2356 | .Sp |
2223 | The usage in rxvt-unicode is simpler. It has a \fIev_cpp.h\fR header file |
2357 | The usage in rxvt-unicode is simpler. It has a \fIev_cpp.h\fR header file |
2224 | that everybody includes and which overrides some autoconf choices: |
2358 | that everybody includes and which overrides some configure choices: |
2225 | .Sp |
2359 | .Sp |
2226 | .Vb 4 |
2360 | .Vb 9 |
|
|
2361 | \& #define EV_MINIMAL 1 |
2227 | \& #define EV_USE_POLL 0 |
2362 | \& #define EV_USE_POLL 0 |
2228 | \& #define EV_MULTIPLICITY 0 |
2363 | \& #define EV_MULTIPLICITY 0 |
2229 | \& #define EV_PERIODICS 0 |
2364 | \& #define EV_PERIODIC_ENABLE 0 |
|
|
2365 | \& #define EV_STAT_ENABLE 0 |
|
|
2366 | \& #define EV_FORK_ENABLE 0 |
2230 | \& #define EV_CONFIG_H <config.h> |
2367 | \& #define EV_CONFIG_H <config.h> |
|
|
2368 | \& #define EV_MINPRI 0 |
|
|
2369 | \& #define EV_MAXPRI 0 |
2231 | .Ve |
2370 | .Ve |
2232 | .Sp |
2371 | .Sp |
2233 | .Vb 1 |
2372 | .Vb 1 |
2234 | \& #include "ev++.h" |
2373 | \& #include "ev++.h" |
2235 | .Ve |
2374 | .Ve |
… | |
… | |
2253 | .IX Item "Changing timer/periodic watchers (by autorepeat, again): O(log skipped_other_timers)" |
2392 | .IX Item "Changing timer/periodic watchers (by autorepeat, again): O(log skipped_other_timers)" |
2254 | .IP "Starting io/check/prepare/idle/signal/child watchers: O(1)" 4 |
2393 | .IP "Starting io/check/prepare/idle/signal/child watchers: O(1)" 4 |
2255 | .IX Item "Starting io/check/prepare/idle/signal/child watchers: O(1)" |
2394 | .IX Item "Starting io/check/prepare/idle/signal/child watchers: O(1)" |
2256 | .IP "Stopping check/prepare/idle watchers: O(1)" 4 |
2395 | .IP "Stopping check/prepare/idle watchers: O(1)" 4 |
2257 | .IX Item "Stopping check/prepare/idle watchers: O(1)" |
2396 | .IX Item "Stopping check/prepare/idle watchers: O(1)" |
2258 | .IP "Stopping an io/signal/child watcher: O(number_of_watchers_for_this_(fd/signal/pid % 16))" 4 |
2397 | .IP "Stopping an io/signal/child watcher: O(number_of_watchers_for_this_(fd/signal/pid % \s-1EV_PID_HASHSIZE\s0))" 4 |
2259 | .IX Item "Stopping an io/signal/child watcher: O(number_of_watchers_for_this_(fd/signal/pid % 16))" |
2398 | .IX Item "Stopping an io/signal/child watcher: O(number_of_watchers_for_this_(fd/signal/pid % EV_PID_HASHSIZE))" |
2260 | .IP "Finding the next timer per loop iteration: O(1)" 4 |
2399 | .IP "Finding the next timer per loop iteration: O(1)" 4 |
2261 | .IX Item "Finding the next timer per loop iteration: O(1)" |
2400 | .IX Item "Finding the next timer per loop iteration: O(1)" |
2262 | .IP "Each change on a file descriptor per loop iteration: O(number_of_watchers_for_this_fd)" 4 |
2401 | .IP "Each change on a file descriptor per loop iteration: O(number_of_watchers_for_this_fd)" 4 |
2263 | .IX Item "Each change on a file descriptor per loop iteration: O(number_of_watchers_for_this_fd)" |
2402 | .IX Item "Each change on a file descriptor per loop iteration: O(number_of_watchers_for_this_fd)" |
2264 | .IP "Activating one watcher: O(1)" 4 |
2403 | .IP "Activating one watcher: O(1)" 4 |