… | |
… | |
127 | .\} |
127 | .\} |
128 | .rm #[ #] #H #V #F C |
128 | .rm #[ #] #H #V #F C |
129 | .\" ======================================================================== |
129 | .\" ======================================================================== |
130 | .\" |
130 | .\" |
131 | .IX Title "EV 1" |
131 | .IX Title "EV 1" |
132 | .TH EV 1 "2007-12-19" "perl v5.8.8" "User Contributed Perl Documentation" |
132 | .TH EV 1 "2007-12-22" "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 |
137 | .Vb 1 |
… | |
… | |
201 | The newest version of this document is also available as a html-formatted |
201 | The newest version of this document is also available as a html-formatted |
202 | web page you might find easier to navigate when reading it for the first |
202 | web page you might find easier to navigate when reading it for the first |
203 | time: <http://cvs.schmorp.de/libev/ev.html>. |
203 | time: <http://cvs.schmorp.de/libev/ev.html>. |
204 | .PP |
204 | .PP |
205 | Libev is an event loop: you register interest in certain events (such as a |
205 | Libev is an event loop: you register interest in certain events (such as a |
206 | file descriptor being readable or a timeout occuring), and it will manage |
206 | file descriptor being readable or a timeout occurring), and it will manage |
207 | these event sources and provide your program with events. |
207 | these event sources and provide your program with events. |
208 | .PP |
208 | .PP |
209 | To do this, it must take more or less complete control over your process |
209 | To do this, it must take more or less complete control over your process |
210 | (or thread) by executing the \fIevent loop\fR handler, and will then |
210 | (or thread) by executing the \fIevent loop\fR handler, and will then |
211 | communicate events via a callback mechanism. |
211 | communicate events via a callback mechanism. |
… | |
… | |
255 | .IP "ev_tstamp ev_time ()" 4 |
255 | .IP "ev_tstamp ev_time ()" 4 |
256 | .IX Item "ev_tstamp ev_time ()" |
256 | .IX Item "ev_tstamp ev_time ()" |
257 | Returns the current time as libev would use it. Please note that the |
257 | Returns the current time as libev would use it. Please note that the |
258 | \&\f(CW\*(C`ev_now\*(C'\fR function is usually faster and also often returns the timestamp |
258 | \&\f(CW\*(C`ev_now\*(C'\fR function is usually faster and also often returns the timestamp |
259 | you actually want to know. |
259 | you actually want to know. |
|
|
260 | .IP "void ev_sleep (ev_tstamp interval)" 4 |
|
|
261 | .IX Item "void ev_sleep (ev_tstamp interval)" |
|
|
262 | Sleep for the given interval: The current thread will be blocked until |
|
|
263 | either it is interrupted or the given time interval has passed. Basically |
|
|
264 | this is a subsecond-resolution \f(CW\*(C`sleep ()\*(C'\fR. |
260 | .IP "int ev_version_major ()" 4 |
265 | .IP "int ev_version_major ()" 4 |
261 | .IX Item "int ev_version_major ()" |
266 | .IX Item "int ev_version_major ()" |
262 | .PD 0 |
267 | .PD 0 |
263 | .IP "int ev_version_minor ()" 4 |
268 | .IP "int ev_version_minor ()" 4 |
264 | .IX Item "int ev_version_minor ()" |
269 | .IX Item "int ev_version_minor ()" |
… | |
… | |
459 | lot of inactive fds). It scales similarly to select, i.e. O(total_fds). |
464 | lot of inactive fds). It scales similarly to select, i.e. O(total_fds). |
460 | .ie n .IP """EVBACKEND_EPOLL"" (value 4, Linux)" 4 |
465 | .ie n .IP """EVBACKEND_EPOLL"" (value 4, Linux)" 4 |
461 | .el .IP "\f(CWEVBACKEND_EPOLL\fR (value 4, Linux)" 4 |
466 | .el .IP "\f(CWEVBACKEND_EPOLL\fR (value 4, Linux)" 4 |
462 | .IX Item "EVBACKEND_EPOLL (value 4, Linux)" |
467 | .IX Item "EVBACKEND_EPOLL (value 4, Linux)" |
463 | For few fds, this backend is a bit little slower than poll and select, |
468 | For few fds, this backend is a bit little slower than poll and select, |
464 | but it scales phenomenally better. While poll and select usually scale like |
469 | but it scales phenomenally better. While poll and select usually scale |
465 | O(total_fds) where n is the total number of fds (or the highest fd), epoll scales |
470 | like O(total_fds) where n is the total number of fds (or the highest fd), |
466 | either O(1) or O(active_fds). |
471 | epoll scales either O(1) or O(active_fds). The epoll design has a number |
|
|
472 | of shortcomings, such as silently dropping events in some hard-to-detect |
|
|
473 | cases and rewiring a syscall per fd change, no fork support and bad |
|
|
474 | support for dup: |
467 | .Sp |
475 | .Sp |
468 | While stopping and starting an I/O watcher in the same iteration will |
476 | While stopping, setting and starting an I/O watcher in the same iteration |
469 | result in some caching, there is still a syscall per such incident |
477 | will result in some caching, there is still a syscall per such incident |
470 | (because the fd could point to a different file description now), so its |
478 | (because the fd could point to a different file description now), so its |
471 | best to avoid that. Also, \fIdup()\fRed file descriptors might not work very |
479 | best to avoid that. Also, \f(CW\*(C`dup ()\*(C'\fR'ed file descriptors might not work |
472 | well if you register events for both fds. |
480 | very well if you register events for both fds. |
473 | .Sp |
481 | .Sp |
474 | Please note that epoll sometimes generates spurious notifications, so you |
482 | Please note that epoll sometimes generates spurious notifications, so you |
475 | need to use non-blocking I/O or other means to avoid blocking when no data |
483 | need to use non-blocking I/O or other means to avoid blocking when no data |
476 | (or space) is available. |
484 | (or space) is available. |
477 | .ie n .IP """EVBACKEND_KQUEUE"" (value 8, most \s-1BSD\s0 clones)" 4 |
485 | .ie n .IP """EVBACKEND_KQUEUE"" (value 8, most \s-1BSD\s0 clones)" 4 |
478 | .el .IP "\f(CWEVBACKEND_KQUEUE\fR (value 8, most \s-1BSD\s0 clones)" 4 |
486 | .el .IP "\f(CWEVBACKEND_KQUEUE\fR (value 8, most \s-1BSD\s0 clones)" 4 |
479 | .IX Item "EVBACKEND_KQUEUE (value 8, most BSD clones)" |
487 | .IX Item "EVBACKEND_KQUEUE (value 8, most BSD clones)" |
480 | Kqueue deserves special mention, as at the time of this writing, it |
488 | Kqueue deserves special mention, as at the time of this writing, it |
481 | was broken on all BSDs except NetBSD (usually it doesn't work with |
489 | was broken on \fIall\fR BSDs (usually it doesn't work with anything but |
482 | anything but sockets and pipes, except on Darwin, where of course its |
490 | sockets and pipes, except on Darwin, where of course it's completely |
|
|
491 | useless. On NetBSD, it seems to work for all the \s-1FD\s0 types I tested, so it |
483 | completely useless). For this reason its not being \*(L"autodetected\*(R" |
492 | is used by default there). For this reason it's not being \*(L"autodetected\*(R" |
484 | unless you explicitly specify it explicitly in the flags (i.e. using |
493 | unless you explicitly specify it explicitly in the flags (i.e. using |
485 | \&\f(CW\*(C`EVBACKEND_KQUEUE\*(C'\fR). |
494 | \&\f(CW\*(C`EVBACKEND_KQUEUE\*(C'\fR) or libev was compiled on a known-to-be-good (\-enough) |
|
|
495 | system like NetBSD. |
486 | .Sp |
496 | .Sp |
487 | It scales in the same way as the epoll backend, but the interface to the |
497 | It scales in the same way as the epoll backend, but the interface to the |
488 | kernel is more efficient (which says nothing about its actual speed, of |
498 | kernel is more efficient (which says nothing about its actual speed, |
489 | course). While starting and stopping an I/O watcher does not cause an |
499 | of course). While stopping, setting and starting an I/O watcher does |
490 | extra syscall as with epoll, it still adds up to four event changes per |
500 | never cause an extra syscall as with epoll, it still adds up to two event |
491 | incident, so its best to avoid that. |
501 | changes per incident, support for \f(CW\*(C`fork ()\*(C'\fR is very bad and it drops fds |
|
|
502 | silently in similarly hard-to-detetc cases. |
492 | .ie n .IP """EVBACKEND_DEVPOLL"" (value 16, Solaris 8)" 4 |
503 | .ie n .IP """EVBACKEND_DEVPOLL"" (value 16, Solaris 8)" 4 |
493 | .el .IP "\f(CWEVBACKEND_DEVPOLL\fR (value 16, Solaris 8)" 4 |
504 | .el .IP "\f(CWEVBACKEND_DEVPOLL\fR (value 16, Solaris 8)" 4 |
494 | .IX Item "EVBACKEND_DEVPOLL (value 16, Solaris 8)" |
505 | .IX Item "EVBACKEND_DEVPOLL (value 16, Solaris 8)" |
495 | This is not implemented yet (and might never be). |
506 | This is not implemented yet (and might never be). |
496 | .ie n .IP """EVBACKEND_PORT"" (value 32, Solaris 10)" 4 |
507 | .ie n .IP """EVBACKEND_PORT"" (value 32, Solaris 10)" 4 |
497 | .el .IP "\f(CWEVBACKEND_PORT\fR (value 32, Solaris 10)" 4 |
508 | .el .IP "\f(CWEVBACKEND_PORT\fR (value 32, Solaris 10)" 4 |
498 | .IX Item "EVBACKEND_PORT (value 32, Solaris 10)" |
509 | .IX Item "EVBACKEND_PORT (value 32, Solaris 10)" |
499 | This uses the Solaris 10 port mechanism. As with everything on Solaris, |
510 | This uses the Solaris 10 event port mechanism. As with everything on Solaris, |
500 | it's really slow, but it still scales very well (O(active_fds)). |
511 | it's really slow, but it still scales very well (O(active_fds)). |
501 | .Sp |
512 | .Sp |
502 | Please note that solaris ports can result in a lot of spurious |
513 | Please note that solaris event ports can deliver a lot of spurious |
503 | notifications, so you need to use non-blocking I/O or other means to avoid |
514 | notifications, so you need to use non-blocking I/O or other means to avoid |
504 | blocking when no data (or space) is available. |
515 | blocking when no data (or space) is available. |
505 | .ie n .IP """EVBACKEND_ALL""" 4 |
516 | .ie n .IP """EVBACKEND_ALL""" 4 |
506 | .el .IP "\f(CWEVBACKEND_ALL\fR" 4 |
517 | .el .IP "\f(CWEVBACKEND_ALL\fR" 4 |
507 | .IX Item "EVBACKEND_ALL" |
518 | .IX Item "EVBACKEND_ALL" |
… | |
… | |
560 | responsibility to either stop all watchers cleanly yoursef \fIbefore\fR |
571 | responsibility to either stop all watchers cleanly yoursef \fIbefore\fR |
561 | calling this function, or cope with the fact afterwards (which is usually |
572 | calling this function, or cope with the fact afterwards (which is usually |
562 | the easiest thing, you can just ignore the watchers and/or \f(CW\*(C`free ()\*(C'\fR them |
573 | the easiest thing, you can just ignore the watchers and/or \f(CW\*(C`free ()\*(C'\fR them |
563 | for example). |
574 | for example). |
564 | .Sp |
575 | .Sp |
565 | Not that certain global state, such as signal state, will not be freed by |
576 | Note that certain global state, such as signal state, will not be freed by |
566 | this function, and related watchers (such as signal and child watchers) |
577 | this function, and related watchers (such as signal and child watchers) |
567 | would need to be stopped manually. |
578 | would need to be stopped manually. |
568 | .Sp |
579 | .Sp |
569 | In general it is not advisable to call this function except in the |
580 | In general it is not advisable to call this function except in the |
570 | rare occasion where you really need to free e.g. the signal handling |
581 | rare occasion where you really need to free e.g. the signal handling |
… | |
… | |
618 | .IX Item "ev_tstamp ev_now (loop)" |
629 | .IX Item "ev_tstamp ev_now (loop)" |
619 | Returns the current \*(L"event loop time\*(R", which is the time the event loop |
630 | Returns the current \*(L"event loop time\*(R", which is the time the event loop |
620 | received events and started processing them. This timestamp does not |
631 | received events and started processing them. This timestamp does not |
621 | change as long as callbacks are being processed, and this is also the base |
632 | change as long as callbacks are being processed, and this is also the base |
622 | time used for relative timers. You can treat it as the timestamp of the |
633 | time used for relative timers. You can treat it as the timestamp of the |
623 | event occuring (or more correctly, libev finding out about it). |
634 | event occurring (or more correctly, libev finding out about it). |
624 | .IP "ev_loop (loop, int flags)" 4 |
635 | .IP "ev_loop (loop, int flags)" 4 |
625 | .IX Item "ev_loop (loop, int flags)" |
636 | .IX Item "ev_loop (loop, int flags)" |
626 | Finally, this is it, the event handler. This function usually is called |
637 | Finally, this is it, the event handler. This function usually is called |
627 | after you initialised all your watchers and you want to start handling |
638 | after you initialised all your watchers and you want to start handling |
628 | events. |
639 | events. |
… | |
… | |
718 | .Sp |
729 | .Sp |
719 | .Vb 2 |
730 | .Vb 2 |
720 | \& ev_ref (loop); |
731 | \& ev_ref (loop); |
721 | \& ev_signal_stop (loop, &exitsig); |
732 | \& ev_signal_stop (loop, &exitsig); |
722 | .Ve |
733 | .Ve |
|
|
734 | .IP "ev_set_io_collect_interval (ev_tstamp interval)" 4 |
|
|
735 | .IX Item "ev_set_io_collect_interval (ev_tstamp interval)" |
|
|
736 | .PD 0 |
|
|
737 | .IP "ev_set_timeout_collect_interval (ev_tstamp interval)" 4 |
|
|
738 | .IX Item "ev_set_timeout_collect_interval (ev_tstamp interval)" |
|
|
739 | .PD |
|
|
740 | These advanced functions influence the time that libev will spend waiting |
|
|
741 | for events. Both are by default \f(CW0\fR, meaning that libev will try to |
|
|
742 | invoke timer/periodic callbacks and I/O callbacks with minimum latency. |
|
|
743 | .Sp |
|
|
744 | Setting these to a higher value (the \f(CW\*(C`interval\*(C'\fR \fImust\fR be >= \f(CW0\fR) |
|
|
745 | allows libev to delay invocation of I/O and timer/periodic callbacks to |
|
|
746 | increase efficiency of loop iterations. |
|
|
747 | .Sp |
|
|
748 | The background is that sometimes your program runs just fast enough to |
|
|
749 | handle one (or very few) event(s) per loop iteration. While this makes |
|
|
750 | the program responsive, it also wastes a lot of \s-1CPU\s0 time to poll for new |
|
|
751 | events, especially with backends like \f(CW\*(C`select ()\*(C'\fR which have a high |
|
|
752 | overhead for the actual polling but can deliver many events at once. |
|
|
753 | .Sp |
|
|
754 | By setting a higher \fIio collect interval\fR you allow libev to spend more |
|
|
755 | time collecting I/O events, so you can handle more events per iteration, |
|
|
756 | at the cost of increasing latency. Timeouts (both \f(CW\*(C`ev_periodic\*(C'\fR and |
|
|
757 | \&\f(CW\*(C`ev_timer\*(C'\fR) will be not affected. |
|
|
758 | .Sp |
|
|
759 | Likewise, by setting a higher \fItimeout collect interval\fR you allow libev |
|
|
760 | to spend more time collecting timeouts, at the expense of increased |
|
|
761 | latency (the watcher callback will be called later). \f(CW\*(C`ev_io\*(C'\fR watchers |
|
|
762 | will not be affected. |
|
|
763 | .Sp |
|
|
764 | Many programs can usually benefit by setting the io collect interval to |
|
|
765 | a value near \f(CW0.1\fR or so, which is often enough for interactive servers |
|
|
766 | (of course not for games), likewise for timeouts. It usually doesn't make |
|
|
767 | much sense to set it to a lower value than \f(CW0.01\fR, as this approsaches |
|
|
768 | the timing granularity of most systems. |
723 | .SH "ANATOMY OF A WATCHER" |
769 | .SH "ANATOMY OF A WATCHER" |
724 | .IX Header "ANATOMY OF A WATCHER" |
770 | .IX Header "ANATOMY OF A WATCHER" |
725 | A watcher is a structure that you create and register to record your |
771 | A watcher is a structure that you create and register to record your |
726 | interest in some event. For instance, if you want to wait for \s-1STDIN\s0 to |
772 | interest in some event. For instance, if you want to wait for \s-1STDIN\s0 to |
727 | become readable, you would create an \f(CW\*(C`ev_io\*(C'\fR watcher for that: |
773 | become readable, you would create an \f(CW\*(C`ev_io\*(C'\fR watcher for that: |
… | |
… | |
1080 | its own, so its quite safe to use). |
1126 | its own, so its quite safe to use). |
1081 | .PP |
1127 | .PP |
1082 | \fIThe special problem of disappearing file descriptors\fR |
1128 | \fIThe special problem of disappearing file descriptors\fR |
1083 | .IX Subsection "The special problem of disappearing file descriptors" |
1129 | .IX Subsection "The special problem of disappearing file descriptors" |
1084 | .PP |
1130 | .PP |
1085 | Some backends (e.g kqueue, epoll) need to be told about closing a file |
1131 | Some backends (e.g. kqueue, epoll) need to be told about closing a file |
1086 | descriptor (either by calling \f(CW\*(C`close\*(C'\fR explicitly or by any other means, |
1132 | descriptor (either by calling \f(CW\*(C`close\*(C'\fR explicitly or by any other means, |
1087 | such as \f(CW\*(C`dup\*(C'\fR). The reason is that you register interest in some file |
1133 | such as \f(CW\*(C`dup\*(C'\fR). The reason is that you register interest in some file |
1088 | descriptor, but when it goes away, the operating system will silently drop |
1134 | descriptor, but when it goes away, the operating system will silently drop |
1089 | this interest. If another file descriptor with the same number then is |
1135 | this interest. If another file descriptor with the same number then is |
1090 | registered with libev, there is no efficient way to see that this is, in |
1136 | registered with libev, there is no efficient way to see that this is, in |
… | |
… | |
1098 | descriptor even if the file descriptor number itself did not change. |
1144 | descriptor even if the file descriptor number itself did not change. |
1099 | .PP |
1145 | .PP |
1100 | This is how one would do it normally anyway, the important point is that |
1146 | This is how one would do it normally anyway, the important point is that |
1101 | the libev application should not optimise around libev but should leave |
1147 | the libev application should not optimise around libev but should leave |
1102 | optimisations to libev. |
1148 | optimisations to libev. |
|
|
1149 | .PP |
|
|
1150 | \fIThe special problem of dup'ed file descriptors\fR |
|
|
1151 | .IX Subsection "The special problem of dup'ed file descriptors" |
|
|
1152 | .PP |
|
|
1153 | Some backends (e.g. epoll), cannot register events for file descriptors, |
|
|
1154 | but only events for the underlying file descriptions. That menas when you |
|
|
1155 | have \f(CW\*(C`dup ()\*(C'\fR'ed file descriptors and register events for them, only one |
|
|
1156 | file descriptor might actually receive events. |
|
|
1157 | .PP |
|
|
1158 | There is no workaorund possible except not registering events |
|
|
1159 | for potentially \f(CW\*(C`dup ()\*(C'\fR'ed file descriptors or to resort to |
|
|
1160 | \&\f(CW\*(C`EVBACKEND_SELECT\*(C'\fR or \f(CW\*(C`EVBACKEND_POLL\*(C'\fR. |
|
|
1161 | .PP |
|
|
1162 | \fIThe special problem of fork\fR |
|
|
1163 | .IX Subsection "The special problem of fork" |
|
|
1164 | .PP |
|
|
1165 | Some backends (epoll, kqueue) do not support \f(CW\*(C`fork ()\*(C'\fR at all or exhibit |
|
|
1166 | useless behaviour. Libev fully supports fork, but needs to be told about |
|
|
1167 | it in the child. |
|
|
1168 | .PP |
|
|
1169 | To support fork in your programs, you either have to call |
|
|
1170 | \&\f(CW\*(C`ev_default_fork ()\*(C'\fR or \f(CW\*(C`ev_loop_fork ()\*(C'\fR after a fork in the child, |
|
|
1171 | enable \f(CW\*(C`EVFLAG_FORKCHECK\*(C'\fR, or resort to \f(CW\*(C`EVBACKEND_SELECT\*(C'\fR or |
|
|
1172 | \&\f(CW\*(C`EVBACKEND_POLL\*(C'\fR. |
1103 | .PP |
1173 | .PP |
1104 | \fIWatcher-Specific Functions\fR |
1174 | \fIWatcher-Specific Functions\fR |
1105 | .IX Subsection "Watcher-Specific Functions" |
1175 | .IX Subsection "Watcher-Specific Functions" |
1106 | .IP "ev_io_init (ev_io *, callback, int fd, int events)" 4 |
1176 | .IP "ev_io_init (ev_io *, callback, int fd, int events)" 4 |
1107 | .IX Item "ev_io_init (ev_io *, callback, int fd, int events)" |
1177 | .IX Item "ev_io_init (ev_io *, callback, int fd, int events)" |
… | |
… | |
1906 | .el .Sh "\f(CWev_embed\fP \- when one backend isn't enough..." |
1976 | .el .Sh "\f(CWev_embed\fP \- when one backend isn't enough..." |
1907 | .IX Subsection "ev_embed - when one backend isn't enough..." |
1977 | .IX Subsection "ev_embed - when one backend isn't enough..." |
1908 | This is a rather advanced watcher type that lets you embed one event loop |
1978 | This is a rather advanced watcher type that lets you embed one event loop |
1909 | into another (currently only \f(CW\*(C`ev_io\*(C'\fR events are supported in the embedded |
1979 | into another (currently only \f(CW\*(C`ev_io\*(C'\fR events are supported in the embedded |
1910 | loop, other types of watchers might be handled in a delayed or incorrect |
1980 | loop, other types of watchers might be handled in a delayed or incorrect |
1911 | fashion and must not be used). |
1981 | fashion and must not be used). (See portability notes, below). |
1912 | .PP |
1982 | .PP |
1913 | There are primarily two reasons you would want that: work around bugs and |
1983 | There are primarily two reasons you would want that: work around bugs and |
1914 | prioritise I/O. |
1984 | prioritise I/O. |
1915 | .PP |
1985 | .PP |
1916 | As an example for a bug workaround, the kqueue backend might only support |
1986 | As an example for a bug workaround, the kqueue backend might only support |
… | |
… | |
1976 | \& ev_embed_start (loop_hi, &embed); |
2046 | \& ev_embed_start (loop_hi, &embed); |
1977 | \& } |
2047 | \& } |
1978 | \& else |
2048 | \& else |
1979 | \& loop_lo = loop_hi; |
2049 | \& loop_lo = loop_hi; |
1980 | .Ve |
2050 | .Ve |
|
|
2051 | .Sh "Portability notes" |
|
|
2052 | .IX Subsection "Portability notes" |
|
|
2053 | Kqueue is nominally embeddable, but this is broken on all BSDs that I |
|
|
2054 | tried, in various ways. Usually the embedded event loop will simply never |
|
|
2055 | receive events, sometimes it will only trigger a few times, sometimes in a |
|
|
2056 | loop. Epoll is also nominally embeddable, but many Linux kernel versions |
|
|
2057 | will always eport the epoll fd as ready, even when no events are pending. |
|
|
2058 | .PP |
|
|
2059 | While libev allows embedding these backends (they are contained in |
|
|
2060 | \&\f(CW\*(C`ev_embeddable_backends ()\*(C'\fR), take extreme care that it will actually |
|
|
2061 | work. |
|
|
2062 | .PP |
|
|
2063 | When in doubt, create a dynamic event loop forced to use sockets (this |
|
|
2064 | usually works) and possibly another thread and a pipe or so to report to |
|
|
2065 | your main event loop. |
1981 | .PP |
2066 | .PP |
1982 | \fIWatcher-Specific Functions and Data Members\fR |
2067 | \fIWatcher-Specific Functions and Data Members\fR |
1983 | .IX Subsection "Watcher-Specific Functions and Data Members" |
2068 | .IX Subsection "Watcher-Specific Functions and Data Members" |
1984 | .IP "ev_embed_init (ev_embed *, callback, struct ev_loop *embedded_loop)" 4 |
2069 | .IP "ev_embed_init (ev_embed *, callback, struct ev_loop *embedded_loop)" 4 |
1985 | .IX Item "ev_embed_init (ev_embed *, callback, struct ev_loop *embedded_loop)" |
2070 | .IX Item "ev_embed_init (ev_embed *, callback, struct ev_loop *embedded_loop)" |
… | |
… | |
1995 | .IP "ev_embed_sweep (loop, ev_embed *)" 4 |
2080 | .IP "ev_embed_sweep (loop, ev_embed *)" 4 |
1996 | .IX Item "ev_embed_sweep (loop, ev_embed *)" |
2081 | .IX Item "ev_embed_sweep (loop, ev_embed *)" |
1997 | Make a single, non-blocking sweep over the embedded loop. This works |
2082 | Make a single, non-blocking sweep over the embedded loop. This works |
1998 | similarly to \f(CW\*(C`ev_loop (embedded_loop, EVLOOP_NONBLOCK)\*(C'\fR, but in the most |
2083 | similarly to \f(CW\*(C`ev_loop (embedded_loop, EVLOOP_NONBLOCK)\*(C'\fR, but in the most |
1999 | apropriate way for embedded loops. |
2084 | apropriate way for embedded loops. |
2000 | .IP "struct ev_loop *loop [read\-only]" 4 |
2085 | .IP "struct ev_loop *other [read\-only]" 4 |
2001 | .IX Item "struct ev_loop *loop [read-only]" |
2086 | .IX Item "struct ev_loop *other [read-only]" |
2002 | The embedded event loop. |
2087 | The embedded event loop. |
2003 | .ie n .Sh """ev_fork"" \- the audacity to resume the event loop after a fork" |
2088 | .ie n .Sh """ev_fork"" \- the audacity to resume the event loop after a fork" |
2004 | .el .Sh "\f(CWev_fork\fP \- the audacity to resume the event loop after a fork" |
2089 | .el .Sh "\f(CWev_fork\fP \- the audacity to resume the event loop after a fork" |
2005 | .IX Subsection "ev_fork - the audacity to resume the event loop after a fork" |
2090 | .IX Subsection "ev_fork - the audacity to resume the event loop after a fork" |
2006 | Fork watchers are called when a \f(CW\*(C`fork ()\*(C'\fR was detected (usually because |
2091 | Fork watchers are called when a \f(CW\*(C`fork ()\*(C'\fR was detected (usually because |
… | |
… | |
2330 | Libev can (and often is) directly embedded into host |
2415 | Libev can (and often is) directly embedded into host |
2331 | applications. Examples of applications that embed it include the Deliantra |
2416 | applications. Examples of applications that embed it include the Deliantra |
2332 | Game Server, the \s-1EV\s0 perl module, the \s-1GNU\s0 Virtual Private Ethernet (gvpe) |
2417 | Game Server, the \s-1EV\s0 perl module, the \s-1GNU\s0 Virtual Private Ethernet (gvpe) |
2333 | and rxvt\-unicode. |
2418 | and rxvt\-unicode. |
2334 | .PP |
2419 | .PP |
2335 | The goal is to enable you to just copy the neecssary files into your |
2420 | The goal is to enable you to just copy the necessary files into your |
2336 | source directory without having to change even a single line in them, so |
2421 | source directory without having to change even a single line in them, so |
2337 | you can easily upgrade by simply copying (or having a checked-out copy of |
2422 | you can easily upgrade by simply copying (or having a checked-out copy of |
2338 | libev somewhere in your source tree). |
2423 | libev somewhere in your source tree). |
2339 | .Sh "\s-1FILESETS\s0" |
2424 | .Sh "\s-1FILESETS\s0" |
2340 | .IX Subsection "FILESETS" |
2425 | .IX Subsection "FILESETS" |
… | |
… | |
2445 | .IX Item "EV_USE_MONOTONIC" |
2530 | .IX Item "EV_USE_MONOTONIC" |
2446 | If defined to be \f(CW1\fR, libev will try to detect the availability of the |
2531 | If defined to be \f(CW1\fR, libev will try to detect the availability of the |
2447 | monotonic clock option at both compiletime and runtime. Otherwise no use |
2532 | monotonic clock option at both compiletime and runtime. Otherwise no use |
2448 | of the monotonic clock option will be attempted. If you enable this, you |
2533 | of the monotonic clock option will be attempted. If you enable this, you |
2449 | usually have to link against librt or something similar. Enabling it when |
2534 | usually have to link against librt or something similar. Enabling it when |
2450 | the functionality isn't available is safe, though, althoguh you have |
2535 | the functionality isn't available is safe, though, although you have |
2451 | to make sure you link against any libraries where the \f(CW\*(C`clock_gettime\*(C'\fR |
2536 | to make sure you link against any libraries where the \f(CW\*(C`clock_gettime\*(C'\fR |
2452 | function is hiding in (often \fI\-lrt\fR). |
2537 | function is hiding in (often \fI\-lrt\fR). |
2453 | .IP "\s-1EV_USE_REALTIME\s0" 4 |
2538 | .IP "\s-1EV_USE_REALTIME\s0" 4 |
2454 | .IX Item "EV_USE_REALTIME" |
2539 | .IX Item "EV_USE_REALTIME" |
2455 | If defined to be \f(CW1\fR, libev will try to detect the availability of the |
2540 | If defined to be \f(CW1\fR, libev will try to detect the availability of the |
2456 | realtime clock option at compiletime (and assume its availability at |
2541 | realtime clock option at compiletime (and assume its availability at |
2457 | runtime if successful). Otherwise no use of the realtime clock option will |
2542 | runtime if successful). Otherwise no use of the realtime clock option will |
2458 | be attempted. This effectively replaces \f(CW\*(C`gettimeofday\*(C'\fR by \f(CW\*(C`clock_get |
2543 | be attempted. This effectively replaces \f(CW\*(C`gettimeofday\*(C'\fR by \f(CW\*(C`clock_get |
2459 | (CLOCK_REALTIME, ...)\*(C'\fR and will not normally affect correctness. See tzhe note about libraries |
2544 | (CLOCK_REALTIME, ...)\*(C'\fR and will not normally affect correctness. See the |
2460 | in the description of \f(CW\*(C`EV_USE_MONOTONIC\*(C'\fR, though. |
2545 | note about libraries in the description of \f(CW\*(C`EV_USE_MONOTONIC\*(C'\fR, though. |
|
|
2546 | .IP "\s-1EV_USE_NANOSLEEP\s0" 4 |
|
|
2547 | .IX Item "EV_USE_NANOSLEEP" |
|
|
2548 | If defined to be \f(CW1\fR, libev will assume that \f(CW\*(C`nanosleep ()\*(C'\fR is available |
|
|
2549 | and will use it for delays. Otherwise it will use \f(CW\*(C`select ()\*(C'\fR. |
2461 | .IP "\s-1EV_USE_SELECT\s0" 4 |
2550 | .IP "\s-1EV_USE_SELECT\s0" 4 |
2462 | .IX Item "EV_USE_SELECT" |
2551 | .IX Item "EV_USE_SELECT" |
2463 | If undefined or defined to be \f(CW1\fR, libev will compile in support for the |
2552 | If undefined or defined to be \f(CW1\fR, libev will compile in support for the |
2464 | \&\f(CW\*(C`select\*(C'\fR(2) backend. No attempt at autodetection will be done: if no |
2553 | \&\f(CW\*(C`select\*(C'\fR(2) backend. No attempt at autodetection will be done: if no |
2465 | other method takes over, select will be it. Otherwise the select backend |
2554 | other method takes over, select will be it. Otherwise the select backend |
… | |
… | |
2625 | .IP "ev_set_cb (ev, cb)" 4 |
2714 | .IP "ev_set_cb (ev, cb)" 4 |
2626 | .IX Item "ev_set_cb (ev, cb)" |
2715 | .IX Item "ev_set_cb (ev, cb)" |
2627 | .PD |
2716 | .PD |
2628 | Can be used to change the callback member declaration in each watcher, |
2717 | Can be used to change the callback member declaration in each watcher, |
2629 | and the way callbacks are invoked and set. Must expand to a struct member |
2718 | and the way callbacks are invoked and set. Must expand to a struct member |
2630 | definition and a statement, respectively. See the \fIev.v\fR header file for |
2719 | definition and a statement, respectively. See the \fIev.h\fR header file for |
2631 | their default definitions. One possible use for overriding these is to |
2720 | their default definitions. One possible use for overriding these is to |
2632 | avoid the \f(CW\*(C`struct ev_loop *\*(C'\fR as first argument in all cases, or to use |
2721 | avoid the \f(CW\*(C`struct ev_loop *\*(C'\fR as first argument in all cases, or to use |
2633 | method calls instead of plain function calls in \*(C+. |
2722 | method calls instead of plain function calls in \*(C+. |
2634 | .Sh "\s-1EXPORTED\s0 \s-1API\s0 \s-1SYMBOLS\s0" |
2723 | .Sh "\s-1EXPORTED\s0 \s-1API\s0 \s-1SYMBOLS\s0" |
2635 | .IX Subsection "EXPORTED API SYMBOLS" |
2724 | .IX Subsection "EXPORTED API SYMBOLS" |
… | |
… | |
2644 | .Sp |
2733 | .Sp |
2645 | This can also be used to rename all public symbols to avoid clashes with |
2734 | This can also be used to rename all public symbols to avoid clashes with |
2646 | multiple versions of libev linked together (which is obviously bad in |
2735 | multiple versions of libev linked together (which is obviously bad in |
2647 | itself, but sometimes it is inconvinient to avoid this). |
2736 | itself, but sometimes it is inconvinient to avoid this). |
2648 | .Sp |
2737 | .Sp |
2649 | A sed comamnd like this will create wrapper \f(CW\*(C`#define\*(C'\fR's that you need to |
2738 | A sed command like this will create wrapper \f(CW\*(C`#define\*(C'\fR's that you need to |
2650 | include before including \fIev.h\fR: |
2739 | include before including \fIev.h\fR: |
2651 | .Sp |
2740 | .Sp |
2652 | .Vb 1 |
2741 | .Vb 1 |
2653 | \& <Symbols.ev sed -e "s/.*/#define & myprefix_&/" >wrap.h |
2742 | \& <Symbols.ev sed -e "s/.*/#define & myprefix_&/" >wrap.h |
2654 | .Ve |
2743 | .Ve |