… | |
… | |
126 | . ds Ae AE |
126 | . ds Ae AE |
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 "EV 1" |
132 | .TH "<STANDARD INPUT>" 1 "2007-12-09" "perl v5.8.8" "User Contributed Perl Documentation" |
132 | .TH EV 1 "2007-12-21" "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. |
… | |
… | |
243 | Libev represents time as a single floating point number, representing the |
243 | Libev represents time as a single floating point number, representing the |
244 | (fractional) number of seconds since the (\s-1POSIX\s0) epoch (somewhere near |
244 | (fractional) number of seconds since the (\s-1POSIX\s0) epoch (somewhere near |
245 | the beginning of 1970, details are complicated, don't ask). This type is |
245 | the beginning of 1970, details are complicated, don't ask). This type is |
246 | called \f(CW\*(C`ev_tstamp\*(C'\fR, which is what you should use too. It usually aliases |
246 | called \f(CW\*(C`ev_tstamp\*(C'\fR, which is what you should use too. It usually aliases |
247 | to the \f(CW\*(C`double\*(C'\fR type in C, and when you need to do any calculations on |
247 | to the \f(CW\*(C`double\*(C'\fR type in C, and when you need to do any calculations on |
248 | it, you should treat it as such. |
248 | it, you should treat it as some floatingpoint value. Unlike the name |
|
|
249 | component \f(CW\*(C`stamp\*(C'\fR might indicate, it is also used for time differences |
|
|
250 | throughout libev. |
249 | .SH "GLOBAL FUNCTIONS" |
251 | .SH "GLOBAL FUNCTIONS" |
250 | .IX Header "GLOBAL FUNCTIONS" |
252 | .IX Header "GLOBAL FUNCTIONS" |
251 | These functions can be called anytime, even before initialising the |
253 | These functions can be called anytime, even before initialising the |
252 | library in any way. |
254 | library in any way. |
253 | .IP "ev_tstamp ev_time ()" 4 |
255 | .IP "ev_tstamp ev_time ()" 4 |
… | |
… | |
259 | .IX Item "int ev_version_major ()" |
261 | .IX Item "int ev_version_major ()" |
260 | .PD 0 |
262 | .PD 0 |
261 | .IP "int ev_version_minor ()" 4 |
263 | .IP "int ev_version_minor ()" 4 |
262 | .IX Item "int ev_version_minor ()" |
264 | .IX Item "int ev_version_minor ()" |
263 | .PD |
265 | .PD |
264 | You can find out the major and minor \s-1API/ABI\s0 version numbers of the library |
266 | You can find out the major and minor \s-1ABI\s0 version numbers of the library |
265 | you linked against by calling the functions \f(CW\*(C`ev_version_major\*(C'\fR and |
267 | you linked against by calling the functions \f(CW\*(C`ev_version_major\*(C'\fR and |
266 | \&\f(CW\*(C`ev_version_minor\*(C'\fR. If you want, you can compare against the global |
268 | \&\f(CW\*(C`ev_version_minor\*(C'\fR. If you want, you can compare against the global |
267 | symbols \f(CW\*(C`EV_VERSION_MAJOR\*(C'\fR and \f(CW\*(C`EV_VERSION_MINOR\*(C'\fR, which specify the |
269 | symbols \f(CW\*(C`EV_VERSION_MAJOR\*(C'\fR and \f(CW\*(C`EV_VERSION_MINOR\*(C'\fR, which specify the |
268 | version of the library your program was compiled against. |
270 | version of the library your program was compiled against. |
269 | .Sp |
271 | .Sp |
270 | These version numbers refer to the \s-1API\s0 and \s-1ABI\s0 version of the library, not |
272 | These version numbers refer to the \s-1ABI\s0 version of the library, not the |
271 | the release version. |
273 | release version. |
272 | .Sp |
274 | .Sp |
273 | Usually, it's a good idea to terminate if the major versions mismatch, |
275 | Usually, it's a good idea to terminate if the major versions mismatch, |
274 | as this indicates an incompatible change. Minor versions are usually |
276 | as this indicates an incompatible change. Minor versions are usually |
275 | compatible to older versions, so a larger minor version alone is usually |
277 | compatible to older versions, so a larger minor version alone is usually |
276 | not a problem. |
278 | not a problem. |
… | |
… | |
457 | lot of inactive fds). It scales similarly to select, i.e. O(total_fds). |
459 | lot of inactive fds). It scales similarly to select, i.e. O(total_fds). |
458 | .ie n .IP """EVBACKEND_EPOLL"" (value 4, Linux)" 4 |
460 | .ie n .IP """EVBACKEND_EPOLL"" (value 4, Linux)" 4 |
459 | .el .IP "\f(CWEVBACKEND_EPOLL\fR (value 4, Linux)" 4 |
461 | .el .IP "\f(CWEVBACKEND_EPOLL\fR (value 4, Linux)" 4 |
460 | .IX Item "EVBACKEND_EPOLL (value 4, Linux)" |
462 | .IX Item "EVBACKEND_EPOLL (value 4, Linux)" |
461 | For few fds, this backend is a bit little slower than poll and select, |
463 | For few fds, this backend is a bit little slower than poll and select, |
462 | but it scales phenomenally better. While poll and select usually scale like |
464 | but it scales phenomenally better. While poll and select usually scale |
463 | O(total_fds) where n is the total number of fds (or the highest fd), epoll scales |
465 | like O(total_fds) where n is the total number of fds (or the highest fd), |
464 | either O(1) or O(active_fds). |
466 | epoll scales either O(1) or O(active_fds). The epoll design has a number |
|
|
467 | of shortcomings, such as silently dropping events in some hard-to-detect |
|
|
468 | cases and rewuiring a syscall per fd change, no fork support and bad |
|
|
469 | support for dup: |
465 | .Sp |
470 | .Sp |
466 | While stopping and starting an I/O watcher in the same iteration will |
471 | While stopping, setting and starting an I/O watcher in the same iteration |
467 | result in some caching, there is still a syscall per such incident |
472 | will result in some caching, there is still a syscall per such incident |
468 | (because the fd could point to a different file description now), so its |
473 | (because the fd could point to a different file description now), so its |
469 | best to avoid that. Also, \fIdup()\fRed file descriptors might not work very |
474 | best to avoid that. Also, \f(CW\*(C`dup ()\*(C'\fR'ed file descriptors might not work |
470 | well if you register events for both fds. |
475 | very well if you register events for both fds. |
471 | .Sp |
476 | .Sp |
472 | Please note that epoll sometimes generates spurious notifications, so you |
477 | Please note that epoll sometimes generates spurious notifications, so you |
473 | need to use non-blocking I/O or other means to avoid blocking when no data |
478 | need to use non-blocking I/O or other means to avoid blocking when no data |
474 | (or space) is available. |
479 | (or space) is available. |
475 | .ie n .IP """EVBACKEND_KQUEUE"" (value 8, most \s-1BSD\s0 clones)" 4 |
480 | .ie n .IP """EVBACKEND_KQUEUE"" (value 8, most \s-1BSD\s0 clones)" 4 |
476 | .el .IP "\f(CWEVBACKEND_KQUEUE\fR (value 8, most \s-1BSD\s0 clones)" 4 |
481 | .el .IP "\f(CWEVBACKEND_KQUEUE\fR (value 8, most \s-1BSD\s0 clones)" 4 |
477 | .IX Item "EVBACKEND_KQUEUE (value 8, most BSD clones)" |
482 | .IX Item "EVBACKEND_KQUEUE (value 8, most BSD clones)" |
478 | Kqueue deserves special mention, as at the time of this writing, it |
483 | Kqueue deserves special mention, as at the time of this writing, it |
479 | was broken on all BSDs except NetBSD (usually it doesn't work with |
484 | was broken on \fIall\fR BSDs (usually it doesn't work with anything but |
480 | anything but sockets and pipes, except on Darwin, where of course its |
485 | sockets and pipes, except on Darwin, where of course it's completely |
|
|
486 | useless. On NetBSD, it seems to work for all the \s-1FD\s0 types I tested, so it |
481 | completely useless). For this reason its not being \*(L"autodetected\*(R" |
487 | is used by default there). For this reason it's not being \*(L"autodetected\*(R" |
482 | unless you explicitly specify it explicitly in the flags (i.e. using |
488 | unless you explicitly specify it explicitly in the flags (i.e. using |
483 | \&\f(CW\*(C`EVBACKEND_KQUEUE\*(C'\fR). |
489 | \&\f(CW\*(C`EVBACKEND_KQUEUE\*(C'\fR) or libev was compiled on a known-to-be-good (\-enough) |
|
|
490 | system like NetBSD. |
484 | .Sp |
491 | .Sp |
485 | It scales in the same way as the epoll backend, but the interface to the |
492 | It scales in the same way as the epoll backend, but the interface to the |
486 | kernel is more efficient (which says nothing about its actual speed, of |
493 | kernel is more efficient (which says nothing about its actual speed, |
487 | course). While starting and stopping an I/O watcher does not cause an |
494 | of course). While stopping, setting and starting an I/O watcher does |
488 | extra syscall as with epoll, it still adds up to four event changes per |
495 | never cause an extra syscall as with epoll, it still adds up to two event |
489 | incident, so its best to avoid that. |
496 | changes per incident, support for \f(CW\*(C`fork ()\*(C'\fR is very bad and it drops fds |
|
|
497 | silently in similarly hard-to-detetc cases. |
490 | .ie n .IP """EVBACKEND_DEVPOLL"" (value 16, Solaris 8)" 4 |
498 | .ie n .IP """EVBACKEND_DEVPOLL"" (value 16, Solaris 8)" 4 |
491 | .el .IP "\f(CWEVBACKEND_DEVPOLL\fR (value 16, Solaris 8)" 4 |
499 | .el .IP "\f(CWEVBACKEND_DEVPOLL\fR (value 16, Solaris 8)" 4 |
492 | .IX Item "EVBACKEND_DEVPOLL (value 16, Solaris 8)" |
500 | .IX Item "EVBACKEND_DEVPOLL (value 16, Solaris 8)" |
493 | This is not implemented yet (and might never be). |
501 | This is not implemented yet (and might never be). |
494 | .ie n .IP """EVBACKEND_PORT"" (value 32, Solaris 10)" 4 |
502 | .ie n .IP """EVBACKEND_PORT"" (value 32, Solaris 10)" 4 |
495 | .el .IP "\f(CWEVBACKEND_PORT\fR (value 32, Solaris 10)" 4 |
503 | .el .IP "\f(CWEVBACKEND_PORT\fR (value 32, Solaris 10)" 4 |
496 | .IX Item "EVBACKEND_PORT (value 32, Solaris 10)" |
504 | .IX Item "EVBACKEND_PORT (value 32, Solaris 10)" |
497 | This uses the Solaris 10 port mechanism. As with everything on Solaris, |
505 | This uses the Solaris 10 event port mechanism. As with everything on Solaris, |
498 | it's really slow, but it still scales very well (O(active_fds)). |
506 | it's really slow, but it still scales very well (O(active_fds)). |
499 | .Sp |
507 | .Sp |
500 | Please note that solaris ports can result in a lot of spurious |
508 | Please note that solaris event ports can deliver a lot of spurious |
501 | notifications, so you need to use non-blocking I/O or other means to avoid |
509 | notifications, so you need to use non-blocking I/O or other means to avoid |
502 | blocking when no data (or space) is available. |
510 | blocking when no data (or space) is available. |
503 | .ie n .IP """EVBACKEND_ALL""" 4 |
511 | .ie n .IP """EVBACKEND_ALL""" 4 |
504 | .el .IP "\f(CWEVBACKEND_ALL\fR" 4 |
512 | .el .IP "\f(CWEVBACKEND_ALL\fR" 4 |
505 | .IX Item "EVBACKEND_ALL" |
513 | .IX Item "EVBACKEND_ALL" |
… | |
… | |
555 | Destroys the default loop again (frees all memory and kernel state |
563 | Destroys the default loop again (frees all memory and kernel state |
556 | etc.). None of the active event watchers will be stopped in the normal |
564 | etc.). None of the active event watchers will be stopped in the normal |
557 | sense, so e.g. \f(CW\*(C`ev_is_active\*(C'\fR might still return true. It is your |
565 | sense, so e.g. \f(CW\*(C`ev_is_active\*(C'\fR might still return true. It is your |
558 | responsibility to either stop all watchers cleanly yoursef \fIbefore\fR |
566 | responsibility to either stop all watchers cleanly yoursef \fIbefore\fR |
559 | calling this function, or cope with the fact afterwards (which is usually |
567 | calling this function, or cope with the fact afterwards (which is usually |
560 | the easiest thing, youc na just ignore the watchers and/or \f(CW\*(C`free ()\*(C'\fR them |
568 | the easiest thing, you can just ignore the watchers and/or \f(CW\*(C`free ()\*(C'\fR them |
561 | for example). |
569 | for example). |
|
|
570 | .Sp |
|
|
571 | Note that certain global state, such as signal state, will not be freed by |
|
|
572 | this function, and related watchers (such as signal and child watchers) |
|
|
573 | would need to be stopped manually. |
|
|
574 | .Sp |
|
|
575 | In general it is not advisable to call this function except in the |
|
|
576 | rare occasion where you really need to free e.g. the signal handling |
|
|
577 | pipe fds. If you need dynamically allocated loops it is better to use |
|
|
578 | \&\f(CW\*(C`ev_loop_new\*(C'\fR and \f(CW\*(C`ev_loop_destroy\*(C'\fR). |
562 | .IP "ev_loop_destroy (loop)" 4 |
579 | .IP "ev_loop_destroy (loop)" 4 |
563 | .IX Item "ev_loop_destroy (loop)" |
580 | .IX Item "ev_loop_destroy (loop)" |
564 | Like \f(CW\*(C`ev_default_destroy\*(C'\fR, but destroys an event loop created by an |
581 | Like \f(CW\*(C`ev_default_destroy\*(C'\fR, but destroys an event loop created by an |
565 | earlier call to \f(CW\*(C`ev_loop_new\*(C'\fR. |
582 | earlier call to \f(CW\*(C`ev_loop_new\*(C'\fR. |
566 | .IP "ev_default_fork ()" 4 |
583 | .IP "ev_default_fork ()" 4 |
… | |
… | |
607 | .IX Item "ev_tstamp ev_now (loop)" |
624 | .IX Item "ev_tstamp ev_now (loop)" |
608 | Returns the current \*(L"event loop time\*(R", which is the time the event loop |
625 | Returns the current \*(L"event loop time\*(R", which is the time the event loop |
609 | received events and started processing them. This timestamp does not |
626 | received events and started processing them. This timestamp does not |
610 | change as long as callbacks are being processed, and this is also the base |
627 | change as long as callbacks are being processed, and this is also the base |
611 | time used for relative timers. You can treat it as the timestamp of the |
628 | time used for relative timers. You can treat it as the timestamp of the |
612 | event occuring (or more correctly, libev finding out about it). |
629 | event occurring (or more correctly, libev finding out about it). |
613 | .IP "ev_loop (loop, int flags)" 4 |
630 | .IP "ev_loop (loop, int flags)" 4 |
614 | .IX Item "ev_loop (loop, int flags)" |
631 | .IX Item "ev_loop (loop, int flags)" |
615 | Finally, this is it, the event handler. This function usually is called |
632 | Finally, this is it, the event handler. This function usually is called |
616 | after you initialised all your watchers and you want to start handling |
633 | after you initialised all your watchers and you want to start handling |
617 | events. |
634 | events. |
… | |
… | |
1065 | If you cannot run the fd in non-blocking mode (for example you should not |
1082 | If you cannot run the fd in non-blocking mode (for example you should not |
1066 | play around with an Xlib connection), then you have to seperately re-test |
1083 | play around with an Xlib connection), then you have to seperately re-test |
1067 | whether a file descriptor is really ready with a known-to-be good interface |
1084 | whether a file descriptor is really ready with a known-to-be good interface |
1068 | such as poll (fortunately in our Xlib example, Xlib already does this on |
1085 | such as poll (fortunately in our Xlib example, Xlib already does this on |
1069 | its own, so its quite safe to use). |
1086 | its own, so its quite safe to use). |
|
|
1087 | .PP |
|
|
1088 | \fIThe special problem of disappearing file descriptors\fR |
|
|
1089 | .IX Subsection "The special problem of disappearing file descriptors" |
|
|
1090 | .PP |
|
|
1091 | Some backends (e.g. kqueue, epoll) need to be told about closing a file |
|
|
1092 | descriptor (either by calling \f(CW\*(C`close\*(C'\fR explicitly or by any other means, |
|
|
1093 | such as \f(CW\*(C`dup\*(C'\fR). The reason is that you register interest in some file |
|
|
1094 | descriptor, but when it goes away, the operating system will silently drop |
|
|
1095 | this interest. If another file descriptor with the same number then is |
|
|
1096 | registered with libev, there is no efficient way to see that this is, in |
|
|
1097 | fact, a different file descriptor. |
|
|
1098 | .PP |
|
|
1099 | To avoid having to explicitly tell libev about such cases, libev follows |
|
|
1100 | the following policy: Each time \f(CW\*(C`ev_io_set\*(C'\fR is being called, libev |
|
|
1101 | will assume that this is potentially a new file descriptor, otherwise |
|
|
1102 | it is assumed that the file descriptor stays the same. That means that |
|
|
1103 | you \fIhave\fR to call \f(CW\*(C`ev_io_set\*(C'\fR (or \f(CW\*(C`ev_io_init\*(C'\fR) when you change the |
|
|
1104 | descriptor even if the file descriptor number itself did not change. |
|
|
1105 | .PP |
|
|
1106 | This is how one would do it normally anyway, the important point is that |
|
|
1107 | the libev application should not optimise around libev but should leave |
|
|
1108 | optimisations to libev. |
|
|
1109 | .PP |
|
|
1110 | \fIThe special problem of dup'ed file descriptors\fR |
|
|
1111 | .IX Subsection "The special problem of dup'ed file descriptors" |
|
|
1112 | .PP |
|
|
1113 | Some backends (e.g. epoll), cannot register events for file descriptors, |
|
|
1114 | but only events for the underlying file descriptions. That menas when you |
|
|
1115 | have \f(CW\*(C`dup ()\*(C'\fR'ed file descriptors and register events for them, only one |
|
|
1116 | file descriptor might actually receive events. |
|
|
1117 | .PP |
|
|
1118 | There is no workaorund possible except not registering events |
|
|
1119 | for potentially \f(CW\*(C`dup ()\*(C'\fR'ed file descriptors or to resort to |
|
|
1120 | \&\f(CW\*(C`EVBACKEND_SELECT\*(C'\fR or \f(CW\*(C`EVBACKEND_POLL\*(C'\fR. |
|
|
1121 | .PP |
|
|
1122 | \fIThe special problem of fork\fR |
|
|
1123 | .IX Subsection "The special problem of fork" |
|
|
1124 | .PP |
|
|
1125 | Some backends (epoll, kqueue) do not support \f(CW\*(C`fork ()\*(C'\fR at all or exhibit |
|
|
1126 | useless behaviour. Libev fully supports fork, but needs to be told about |
|
|
1127 | it in the child. |
|
|
1128 | .PP |
|
|
1129 | To support fork in your programs, you either have to call |
|
|
1130 | \&\f(CW\*(C`ev_default_fork ()\*(C'\fR or \f(CW\*(C`ev_loop_fork ()\*(C'\fR after a fork in the child, |
|
|
1131 | enable \f(CW\*(C`EVFLAG_FORKCHECK\*(C'\fR, or resort to \f(CW\*(C`EVBACKEND_SELECT\*(C'\fR or |
|
|
1132 | \&\f(CW\*(C`EVBACKEND_POLL\*(C'\fR. |
|
|
1133 | .PP |
|
|
1134 | \fIWatcher-Specific Functions\fR |
|
|
1135 | .IX Subsection "Watcher-Specific Functions" |
1070 | .IP "ev_io_init (ev_io *, callback, int fd, int events)" 4 |
1136 | .IP "ev_io_init (ev_io *, callback, int fd, int events)" 4 |
1071 | .IX Item "ev_io_init (ev_io *, callback, int fd, int events)" |
1137 | .IX Item "ev_io_init (ev_io *, callback, int fd, int events)" |
1072 | .PD 0 |
1138 | .PD 0 |
1073 | .IP "ev_io_set (ev_io *, int fd, int events)" 4 |
1139 | .IP "ev_io_set (ev_io *, int fd, int events)" 4 |
1074 | .IX Item "ev_io_set (ev_io *, int fd, int events)" |
1140 | .IX Item "ev_io_set (ev_io *, int fd, int events)" |
… | |
… | |
1127 | .Ve |
1193 | .Ve |
1128 | .PP |
1194 | .PP |
1129 | The callback is guarenteed to be invoked only when its timeout has passed, |
1195 | The callback is guarenteed to be invoked only when its timeout has passed, |
1130 | but if multiple timers become ready during the same loop iteration then |
1196 | but if multiple timers become ready during the same loop iteration then |
1131 | order of execution is undefined. |
1197 | order of execution is undefined. |
|
|
1198 | .PP |
|
|
1199 | \fIWatcher-Specific Functions and Data Members\fR |
|
|
1200 | .IX Subsection "Watcher-Specific Functions and Data Members" |
1132 | .IP "ev_timer_init (ev_timer *, callback, ev_tstamp after, ev_tstamp repeat)" 4 |
1201 | .IP "ev_timer_init (ev_timer *, callback, ev_tstamp after, ev_tstamp repeat)" 4 |
1133 | .IX Item "ev_timer_init (ev_timer *, callback, ev_tstamp after, ev_tstamp repeat)" |
1202 | .IX Item "ev_timer_init (ev_timer *, callback, ev_tstamp after, ev_tstamp repeat)" |
1134 | .PD 0 |
1203 | .PD 0 |
1135 | .IP "ev_timer_set (ev_timer *, ev_tstamp after, ev_tstamp repeat)" 4 |
1204 | .IP "ev_timer_set (ev_timer *, ev_tstamp after, ev_tstamp repeat)" 4 |
1136 | .IX Item "ev_timer_set (ev_timer *, ev_tstamp after, ev_tstamp repeat)" |
1205 | .IX Item "ev_timer_set (ev_timer *, ev_tstamp after, ev_tstamp repeat)" |
… | |
… | |
1247 | rules. |
1316 | rules. |
1248 | .PP |
1317 | .PP |
1249 | As with timers, the callback is guarenteed to be invoked only when the |
1318 | As with timers, the callback is guarenteed to be invoked only when the |
1250 | time (\f(CW\*(C`at\*(C'\fR) has been passed, but if multiple periodic timers become ready |
1319 | time (\f(CW\*(C`at\*(C'\fR) has been passed, but if multiple periodic timers become ready |
1251 | during the same loop iteration then order of execution is undefined. |
1320 | during the same loop iteration then order of execution is undefined. |
|
|
1321 | .PP |
|
|
1322 | \fIWatcher-Specific Functions and Data Members\fR |
|
|
1323 | .IX Subsection "Watcher-Specific Functions and Data Members" |
1252 | .IP "ev_periodic_init (ev_periodic *, callback, ev_tstamp at, ev_tstamp interval, reschedule_cb)" 4 |
1324 | .IP "ev_periodic_init (ev_periodic *, callback, ev_tstamp at, ev_tstamp interval, reschedule_cb)" 4 |
1253 | .IX Item "ev_periodic_init (ev_periodic *, callback, ev_tstamp at, ev_tstamp interval, reschedule_cb)" |
1325 | .IX Item "ev_periodic_init (ev_periodic *, callback, ev_tstamp at, ev_tstamp interval, reschedule_cb)" |
1254 | .PD 0 |
1326 | .PD 0 |
1255 | .IP "ev_periodic_set (ev_periodic *, ev_tstamp after, ev_tstamp repeat, reschedule_cb)" 4 |
1327 | .IP "ev_periodic_set (ev_periodic *, ev_tstamp after, ev_tstamp repeat, reschedule_cb)" 4 |
1256 | .IX Item "ev_periodic_set (ev_periodic *, ev_tstamp after, ev_tstamp repeat, reschedule_cb)" |
1328 | .IX Item "ev_periodic_set (ev_periodic *, ev_tstamp after, ev_tstamp repeat, reschedule_cb)" |
… | |
… | |
1348 | .IP "ev_tstamp (*reschedule_cb)(struct ev_periodic *w, ev_tstamp now) [read\-write]" 4 |
1420 | .IP "ev_tstamp (*reschedule_cb)(struct ev_periodic *w, ev_tstamp now) [read\-write]" 4 |
1349 | .IX Item "ev_tstamp (*reschedule_cb)(struct ev_periodic *w, ev_tstamp now) [read-write]" |
1421 | .IX Item "ev_tstamp (*reschedule_cb)(struct ev_periodic *w, ev_tstamp now) [read-write]" |
1350 | The current reschedule callback, or \f(CW0\fR, if this functionality is |
1422 | The current reschedule callback, or \f(CW0\fR, if this functionality is |
1351 | switched off. Can be changed any time, but changes only take effect when |
1423 | switched off. Can be changed any time, but changes only take effect when |
1352 | the periodic timer fires or \f(CW\*(C`ev_periodic_again\*(C'\fR is being called. |
1424 | the periodic timer fires or \f(CW\*(C`ev_periodic_again\*(C'\fR is being called. |
|
|
1425 | .IP "ev_tstamp at [read\-only]" 4 |
|
|
1426 | .IX Item "ev_tstamp at [read-only]" |
|
|
1427 | When active, contains the absolute time that the watcher is supposed to |
|
|
1428 | trigger next. |
1353 | .PP |
1429 | .PP |
1354 | Example: Call a callback every hour, or, more precisely, whenever the |
1430 | Example: Call a callback every hour, or, more precisely, whenever the |
1355 | system clock is divisible by 3600. The callback invocation times have |
1431 | system clock is divisible by 3600. The callback invocation times have |
1356 | potentially a lot of jittering, but good long-term stability. |
1432 | potentially a lot of jittering, but good long-term stability. |
1357 | .PP |
1433 | .PP |
… | |
… | |
1407 | first watcher gets started will libev actually register a signal watcher |
1483 | first watcher gets started will libev actually register a signal watcher |
1408 | with the kernel (thus it coexists with your own signal handlers as long |
1484 | with the kernel (thus it coexists with your own signal handlers as long |
1409 | as you don't register any with libev). Similarly, when the last signal |
1485 | as you don't register any with libev). Similarly, when the last signal |
1410 | watcher for a signal is stopped libev will reset the signal handler to |
1486 | watcher for a signal is stopped libev will reset the signal handler to |
1411 | \&\s-1SIG_DFL\s0 (regardless of what it was set to before). |
1487 | \&\s-1SIG_DFL\s0 (regardless of what it was set to before). |
|
|
1488 | .PP |
|
|
1489 | \fIWatcher-Specific Functions and Data Members\fR |
|
|
1490 | .IX Subsection "Watcher-Specific Functions and Data Members" |
1412 | .IP "ev_signal_init (ev_signal *, callback, int signum)" 4 |
1491 | .IP "ev_signal_init (ev_signal *, callback, int signum)" 4 |
1413 | .IX Item "ev_signal_init (ev_signal *, callback, int signum)" |
1492 | .IX Item "ev_signal_init (ev_signal *, callback, int signum)" |
1414 | .PD 0 |
1493 | .PD 0 |
1415 | .IP "ev_signal_set (ev_signal *, int signum)" 4 |
1494 | .IP "ev_signal_set (ev_signal *, int signum)" 4 |
1416 | .IX Item "ev_signal_set (ev_signal *, int signum)" |
1495 | .IX Item "ev_signal_set (ev_signal *, int signum)" |
… | |
… | |
1423 | .ie n .Sh """ev_child"" \- watch out for process status changes" |
1502 | .ie n .Sh """ev_child"" \- watch out for process status changes" |
1424 | .el .Sh "\f(CWev_child\fP \- watch out for process status changes" |
1503 | .el .Sh "\f(CWev_child\fP \- watch out for process status changes" |
1425 | .IX Subsection "ev_child - watch out for process status changes" |
1504 | .IX Subsection "ev_child - watch out for process status changes" |
1426 | Child watchers trigger when your process receives a \s-1SIGCHLD\s0 in response to |
1505 | Child watchers trigger when your process receives a \s-1SIGCHLD\s0 in response to |
1427 | some child status changes (most typically when a child of yours dies). |
1506 | some child status changes (most typically when a child of yours dies). |
|
|
1507 | .PP |
|
|
1508 | \fIWatcher-Specific Functions and Data Members\fR |
|
|
1509 | .IX Subsection "Watcher-Specific Functions and Data Members" |
1428 | .IP "ev_child_init (ev_child *, callback, int pid)" 4 |
1510 | .IP "ev_child_init (ev_child *, callback, int pid)" 4 |
1429 | .IX Item "ev_child_init (ev_child *, callback, int pid)" |
1511 | .IX Item "ev_child_init (ev_child *, callback, int pid)" |
1430 | .PD 0 |
1512 | .PD 0 |
1431 | .IP "ev_child_set (ev_child *, int pid)" 4 |
1513 | .IP "ev_child_set (ev_child *, int pid)" 4 |
1432 | .IX Item "ev_child_set (ev_child *, int pid)" |
1514 | .IX Item "ev_child_set (ev_child *, int pid)" |
… | |
… | |
1497 | reader). Inotify will be used to give hints only and should not change the |
1579 | reader). Inotify will be used to give hints only and should not change the |
1498 | semantics of \f(CW\*(C`ev_stat\*(C'\fR watchers, which means that libev sometimes needs |
1580 | semantics of \f(CW\*(C`ev_stat\*(C'\fR watchers, which means that libev sometimes needs |
1499 | to fall back to regular polling again even with inotify, but changes are |
1581 | to fall back to regular polling again even with inotify, but changes are |
1500 | usually detected immediately, and if the file exists there will be no |
1582 | usually detected immediately, and if the file exists there will be no |
1501 | polling. |
1583 | polling. |
|
|
1584 | .PP |
|
|
1585 | \fIWatcher-Specific Functions and Data Members\fR |
|
|
1586 | .IX Subsection "Watcher-Specific Functions and Data Members" |
1502 | .IP "ev_stat_init (ev_stat *, callback, const char *path, ev_tstamp interval)" 4 |
1587 | .IP "ev_stat_init (ev_stat *, callback, const char *path, ev_tstamp interval)" 4 |
1503 | .IX Item "ev_stat_init (ev_stat *, callback, const char *path, ev_tstamp interval)" |
1588 | .IX Item "ev_stat_init (ev_stat *, callback, const char *path, ev_tstamp interval)" |
1504 | .PD 0 |
1589 | .PD 0 |
1505 | .IP "ev_stat_set (ev_stat *, const char *path, ev_tstamp interval)" 4 |
1590 | .IP "ev_stat_set (ev_stat *, const char *path, ev_tstamp interval)" 4 |
1506 | .IX Item "ev_stat_set (ev_stat *, const char *path, ev_tstamp interval)" |
1591 | .IX Item "ev_stat_set (ev_stat *, const char *path, ev_tstamp interval)" |
… | |
… | |
1585 | .PP |
1670 | .PP |
1586 | Apart from keeping your process non-blocking (which is a useful |
1671 | Apart from keeping your process non-blocking (which is a useful |
1587 | effect on its own sometimes), idle watchers are a good place to do |
1672 | effect on its own sometimes), idle watchers are a good place to do |
1588 | \&\*(L"pseudo\-background processing\*(R", or delay processing stuff to after the |
1673 | \&\*(L"pseudo\-background processing\*(R", or delay processing stuff to after the |
1589 | event loop has handled all outstanding events. |
1674 | event loop has handled all outstanding events. |
|
|
1675 | .PP |
|
|
1676 | \fIWatcher-Specific Functions and Data Members\fR |
|
|
1677 | .IX Subsection "Watcher-Specific Functions and Data Members" |
1590 | .IP "ev_idle_init (ev_signal *, callback)" 4 |
1678 | .IP "ev_idle_init (ev_signal *, callback)" 4 |
1591 | .IX Item "ev_idle_init (ev_signal *, callback)" |
1679 | .IX Item "ev_idle_init (ev_signal *, callback)" |
1592 | Initialises and configures the idle watcher \- it has no parameters of any |
1680 | Initialises and configures the idle watcher \- it has no parameters of any |
1593 | kind. There is a \f(CW\*(C`ev_idle_set\*(C'\fR macro, but using it is utterly pointless, |
1681 | kind. There is a \f(CW\*(C`ev_idle_set\*(C'\fR macro, but using it is utterly pointless, |
1594 | believe me. |
1682 | believe me. |
… | |
… | |
1659 | supports this, they will be called before other \f(CW\*(C`ev_check\*(C'\fR watchers did |
1747 | supports this, they will be called before other \f(CW\*(C`ev_check\*(C'\fR watchers did |
1660 | their job. As \f(CW\*(C`ev_check\*(C'\fR watchers are often used to embed other event |
1748 | their job. As \f(CW\*(C`ev_check\*(C'\fR watchers are often used to embed other event |
1661 | loops those other event loops might be in an unusable state until their |
1749 | loops those other event loops might be in an unusable state until their |
1662 | \&\f(CW\*(C`ev_check\*(C'\fR watcher ran (always remind yourself to coexist peacefully with |
1750 | \&\f(CW\*(C`ev_check\*(C'\fR watcher ran (always remind yourself to coexist peacefully with |
1663 | others). |
1751 | others). |
|
|
1752 | .PP |
|
|
1753 | \fIWatcher-Specific Functions and Data Members\fR |
|
|
1754 | .IX Subsection "Watcher-Specific Functions and Data Members" |
1664 | .IP "ev_prepare_init (ev_prepare *, callback)" 4 |
1755 | .IP "ev_prepare_init (ev_prepare *, callback)" 4 |
1665 | .IX Item "ev_prepare_init (ev_prepare *, callback)" |
1756 | .IX Item "ev_prepare_init (ev_prepare *, callback)" |
1666 | .PD 0 |
1757 | .PD 0 |
1667 | .IP "ev_check_init (ev_check *, callback)" 4 |
1758 | .IP "ev_check_init (ev_check *, callback)" 4 |
1668 | .IX Item "ev_check_init (ev_check *, callback)" |
1759 | .IX Item "ev_check_init (ev_check *, callback)" |
… | |
… | |
1845 | .el .Sh "\f(CWev_embed\fP \- when one backend isn't enough..." |
1936 | .el .Sh "\f(CWev_embed\fP \- when one backend isn't enough..." |
1846 | .IX Subsection "ev_embed - when one backend isn't enough..." |
1937 | .IX Subsection "ev_embed - when one backend isn't enough..." |
1847 | This is a rather advanced watcher type that lets you embed one event loop |
1938 | This is a rather advanced watcher type that lets you embed one event loop |
1848 | into another (currently only \f(CW\*(C`ev_io\*(C'\fR events are supported in the embedded |
1939 | into another (currently only \f(CW\*(C`ev_io\*(C'\fR events are supported in the embedded |
1849 | loop, other types of watchers might be handled in a delayed or incorrect |
1940 | loop, other types of watchers might be handled in a delayed or incorrect |
1850 | fashion and must not be used). |
1941 | fashion and must not be used). (See portability notes, below). |
1851 | .PP |
1942 | .PP |
1852 | There are primarily two reasons you would want that: work around bugs and |
1943 | There are primarily two reasons you would want that: work around bugs and |
1853 | prioritise I/O. |
1944 | prioritise I/O. |
1854 | .PP |
1945 | .PP |
1855 | As an example for a bug workaround, the kqueue backend might only support |
1946 | As an example for a bug workaround, the kqueue backend might only support |
… | |
… | |
1915 | \& ev_embed_start (loop_hi, &embed); |
2006 | \& ev_embed_start (loop_hi, &embed); |
1916 | \& } |
2007 | \& } |
1917 | \& else |
2008 | \& else |
1918 | \& loop_lo = loop_hi; |
2009 | \& loop_lo = loop_hi; |
1919 | .Ve |
2010 | .Ve |
|
|
2011 | .Sh "Portability notes" |
|
|
2012 | .IX Subsection "Portability notes" |
|
|
2013 | Kqueue is nominally embeddable, but this is broken on all BSDs that I |
|
|
2014 | tried, in various ways. Usually the embedded event loop will simply never |
|
|
2015 | receive events, sometimes it will only trigger a few times, sometimes in a |
|
|
2016 | loop. Epoll is also nominally embeddable, but many Linux kernel versions |
|
|
2017 | will always eport the epoll fd as ready, even when no events are pending. |
|
|
2018 | .PP |
|
|
2019 | While libev allows embedding these backends (they are contained in |
|
|
2020 | \&\f(CW\*(C`ev_embeddable_backends ()\*(C'\fR), take extreme care that it will actually |
|
|
2021 | work. |
|
|
2022 | .PP |
|
|
2023 | When in doubt, create a dynamic event loop forced to use sockets (this |
|
|
2024 | usually works) and possibly another thread and a pipe or so to report to |
|
|
2025 | your main event loop. |
|
|
2026 | .PP |
|
|
2027 | \fIWatcher-Specific Functions and Data Members\fR |
|
|
2028 | .IX Subsection "Watcher-Specific Functions and Data Members" |
1920 | .IP "ev_embed_init (ev_embed *, callback, struct ev_loop *embedded_loop)" 4 |
2029 | .IP "ev_embed_init (ev_embed *, callback, struct ev_loop *embedded_loop)" 4 |
1921 | .IX Item "ev_embed_init (ev_embed *, callback, struct ev_loop *embedded_loop)" |
2030 | .IX Item "ev_embed_init (ev_embed *, callback, struct ev_loop *embedded_loop)" |
1922 | .PD 0 |
2031 | .PD 0 |
1923 | .IP "ev_embed_set (ev_embed *, callback, struct ev_loop *embedded_loop)" 4 |
2032 | .IP "ev_embed_set (ev_embed *, callback, struct ev_loop *embedded_loop)" 4 |
1924 | .IX Item "ev_embed_set (ev_embed *, callback, struct ev_loop *embedded_loop)" |
2033 | .IX Item "ev_embed_set (ev_embed *, callback, struct ev_loop *embedded_loop)" |
… | |
… | |
1931 | .IP "ev_embed_sweep (loop, ev_embed *)" 4 |
2040 | .IP "ev_embed_sweep (loop, ev_embed *)" 4 |
1932 | .IX Item "ev_embed_sweep (loop, ev_embed *)" |
2041 | .IX Item "ev_embed_sweep (loop, ev_embed *)" |
1933 | Make a single, non-blocking sweep over the embedded loop. This works |
2042 | Make a single, non-blocking sweep over the embedded loop. This works |
1934 | similarly to \f(CW\*(C`ev_loop (embedded_loop, EVLOOP_NONBLOCK)\*(C'\fR, but in the most |
2043 | similarly to \f(CW\*(C`ev_loop (embedded_loop, EVLOOP_NONBLOCK)\*(C'\fR, but in the most |
1935 | apropriate way for embedded loops. |
2044 | apropriate way for embedded loops. |
1936 | .IP "struct ev_loop *loop [read\-only]" 4 |
2045 | .IP "struct ev_loop *other [read\-only]" 4 |
1937 | .IX Item "struct ev_loop *loop [read-only]" |
2046 | .IX Item "struct ev_loop *other [read-only]" |
1938 | The embedded event loop. |
2047 | The embedded event loop. |
1939 | .ie n .Sh """ev_fork"" \- the audacity to resume the event loop after a fork" |
2048 | .ie n .Sh """ev_fork"" \- the audacity to resume the event loop after a fork" |
1940 | .el .Sh "\f(CWev_fork\fP \- the audacity to resume the event loop after a fork" |
2049 | .el .Sh "\f(CWev_fork\fP \- the audacity to resume the event loop after a fork" |
1941 | .IX Subsection "ev_fork - the audacity to resume the event loop after a fork" |
2050 | .IX Subsection "ev_fork - the audacity to resume the event loop after a fork" |
1942 | Fork watchers are called when a \f(CW\*(C`fork ()\*(C'\fR was detected (usually because |
2051 | Fork watchers are called when a \f(CW\*(C`fork ()\*(C'\fR was detected (usually because |
… | |
… | |
1944 | \&\f(CW\*(C`ev_default_fork\*(C'\fR or \f(CW\*(C`ev_loop_fork\*(C'\fR). The invocation is done before the |
2053 | \&\f(CW\*(C`ev_default_fork\*(C'\fR or \f(CW\*(C`ev_loop_fork\*(C'\fR). The invocation is done before the |
1945 | event loop blocks next and before \f(CW\*(C`ev_check\*(C'\fR watchers are being called, |
2054 | event loop blocks next and before \f(CW\*(C`ev_check\*(C'\fR watchers are being called, |
1946 | and only in the child after the fork. If whoever good citizen calling |
2055 | and only in the child after the fork. If whoever good citizen calling |
1947 | \&\f(CW\*(C`ev_default_fork\*(C'\fR cheats and calls it in the wrong process, the fork |
2056 | \&\f(CW\*(C`ev_default_fork\*(C'\fR cheats and calls it in the wrong process, the fork |
1948 | handlers will be invoked, too, of course. |
2057 | handlers will be invoked, too, of course. |
|
|
2058 | .PP |
|
|
2059 | \fIWatcher-Specific Functions and Data Members\fR |
|
|
2060 | .IX Subsection "Watcher-Specific Functions and Data Members" |
1949 | .IP "ev_fork_init (ev_signal *, callback)" 4 |
2061 | .IP "ev_fork_init (ev_signal *, callback)" 4 |
1950 | .IX Item "ev_fork_init (ev_signal *, callback)" |
2062 | .IX Item "ev_fork_init (ev_signal *, callback)" |
1951 | Initialises and configures the fork watcher \- it has no parameters of any |
2063 | Initialises and configures the fork watcher \- it has no parameters of any |
1952 | kind. There is a \f(CW\*(C`ev_fork_set\*(C'\fR macro, but using it is utterly pointless, |
2064 | kind. There is a \f(CW\*(C`ev_fork_set\*(C'\fR macro, but using it is utterly pointless, |
1953 | believe me. |
2065 | believe me. |
… | |
… | |
2147 | Starts the watcher. Note that there is no \f(CW\*(C`loop\*(C'\fR argument, as the |
2259 | Starts the watcher. Note that there is no \f(CW\*(C`loop\*(C'\fR argument, as the |
2148 | constructor already stores the event loop. |
2260 | constructor already stores the event loop. |
2149 | .IP "w\->stop ()" 4 |
2261 | .IP "w\->stop ()" 4 |
2150 | .IX Item "w->stop ()" |
2262 | .IX Item "w->stop ()" |
2151 | Stops the watcher if it is active. Again, no \f(CW\*(C`loop\*(C'\fR argument. |
2263 | Stops the watcher if it is active. Again, no \f(CW\*(C`loop\*(C'\fR argument. |
2152 | .ie n .IP "w\->again () ""ev::timer""\fR, \f(CW""ev::periodic"" only" 4 |
2264 | .ie n .IP "w\->again () (""ev::timer""\fR, \f(CW""ev::periodic"" only)" 4 |
2153 | .el .IP "w\->again () \f(CWev::timer\fR, \f(CWev::periodic\fR only" 4 |
2265 | .el .IP "w\->again () (\f(CWev::timer\fR, \f(CWev::periodic\fR only)" 4 |
2154 | .IX Item "w->again () ev::timer, ev::periodic only" |
2266 | .IX Item "w->again () (ev::timer, ev::periodic only)" |
2155 | For \f(CW\*(C`ev::timer\*(C'\fR and \f(CW\*(C`ev::periodic\*(C'\fR, this invokes the corresponding |
2267 | For \f(CW\*(C`ev::timer\*(C'\fR and \f(CW\*(C`ev::periodic\*(C'\fR, this invokes the corresponding |
2156 | \&\f(CW\*(C`ev_TYPE_again\*(C'\fR function. |
2268 | \&\f(CW\*(C`ev_TYPE_again\*(C'\fR function. |
2157 | .ie n .IP "w\->sweep () ""ev::embed"" only" 4 |
2269 | .ie n .IP "w\->sweep () (""ev::embed"" only)" 4 |
2158 | .el .IP "w\->sweep () \f(CWev::embed\fR only" 4 |
2270 | .el .IP "w\->sweep () (\f(CWev::embed\fR only)" 4 |
2159 | .IX Item "w->sweep () ev::embed only" |
2271 | .IX Item "w->sweep () (ev::embed only)" |
2160 | Invokes \f(CW\*(C`ev_embed_sweep\*(C'\fR. |
2272 | Invokes \f(CW\*(C`ev_embed_sweep\*(C'\fR. |
2161 | .ie n .IP "w\->update () ""ev::stat"" only" 4 |
2273 | .ie n .IP "w\->update () (""ev::stat"" only)" 4 |
2162 | .el .IP "w\->update () \f(CWev::stat\fR only" 4 |
2274 | .el .IP "w\->update () (\f(CWev::stat\fR only)" 4 |
2163 | .IX Item "w->update () ev::stat only" |
2275 | .IX Item "w->update () (ev::stat only)" |
2164 | Invokes \f(CW\*(C`ev_stat_stat\*(C'\fR. |
2276 | Invokes \f(CW\*(C`ev_stat_stat\*(C'\fR. |
2165 | .RE |
2277 | .RE |
2166 | .RS 4 |
2278 | .RS 4 |
2167 | .RE |
2279 | .RE |
2168 | .PP |
2280 | .PP |
… | |
… | |
2192 | \& io.start (fd, ev::READ); |
2304 | \& io.start (fd, ev::READ); |
2193 | \& } |
2305 | \& } |
2194 | .Ve |
2306 | .Ve |
2195 | .SH "MACRO MAGIC" |
2307 | .SH "MACRO MAGIC" |
2196 | .IX Header "MACRO MAGIC" |
2308 | .IX Header "MACRO MAGIC" |
2197 | Libev can be compiled with a variety of options, the most fundemantal is |
2309 | Libev can be compiled with a variety of options, the most fundamantal |
2198 | \&\f(CW\*(C`EV_MULTIPLICITY\*(C'\fR. This option determines whether (most) functions and |
2310 | of which is \f(CW\*(C`EV_MULTIPLICITY\*(C'\fR. This option determines whether (most) |
2199 | callbacks have an initial \f(CW\*(C`struct ev_loop *\*(C'\fR argument. |
2311 | functions and callbacks have an initial \f(CW\*(C`struct ev_loop *\*(C'\fR argument. |
2200 | .PP |
2312 | .PP |
2201 | To make it easier to write programs that cope with either variant, the |
2313 | To make it easier to write programs that cope with either variant, the |
2202 | following macros are defined: |
2314 | following macros are defined: |
2203 | .ie n .IP """EV_A""\fR, \f(CW""EV_A_""" 4 |
2315 | .ie n .IP """EV_A""\fR, \f(CW""EV_A_""" 4 |
2204 | .el .IP "\f(CWEV_A\fR, \f(CWEV_A_\fR" 4 |
2316 | .el .IP "\f(CWEV_A\fR, \f(CWEV_A_\fR" 4 |
… | |
… | |
2263 | Libev can (and often is) directly embedded into host |
2375 | Libev can (and often is) directly embedded into host |
2264 | applications. Examples of applications that embed it include the Deliantra |
2376 | applications. Examples of applications that embed it include the Deliantra |
2265 | Game Server, the \s-1EV\s0 perl module, the \s-1GNU\s0 Virtual Private Ethernet (gvpe) |
2377 | Game Server, the \s-1EV\s0 perl module, the \s-1GNU\s0 Virtual Private Ethernet (gvpe) |
2266 | and rxvt\-unicode. |
2378 | and rxvt\-unicode. |
2267 | .PP |
2379 | .PP |
2268 | The goal is to enable you to just copy the neecssary files into your |
2380 | The goal is to enable you to just copy the necessary files into your |
2269 | source directory without having to change even a single line in them, so |
2381 | source directory without having to change even a single line in them, so |
2270 | you can easily upgrade by simply copying (or having a checked-out copy of |
2382 | you can easily upgrade by simply copying (or having a checked-out copy of |
2271 | libev somewhere in your source tree). |
2383 | libev somewhere in your source tree). |
2272 | .Sh "\s-1FILESETS\s0" |
2384 | .Sh "\s-1FILESETS\s0" |
2273 | .IX Subsection "FILESETS" |
2385 | .IX Subsection "FILESETS" |
… | |
… | |
2378 | .IX Item "EV_USE_MONOTONIC" |
2490 | .IX Item "EV_USE_MONOTONIC" |
2379 | If defined to be \f(CW1\fR, libev will try to detect the availability of the |
2491 | If defined to be \f(CW1\fR, libev will try to detect the availability of the |
2380 | monotonic clock option at both compiletime and runtime. Otherwise no use |
2492 | monotonic clock option at both compiletime and runtime. Otherwise no use |
2381 | of the monotonic clock option will be attempted. If you enable this, you |
2493 | of the monotonic clock option will be attempted. If you enable this, you |
2382 | usually have to link against librt or something similar. Enabling it when |
2494 | usually have to link against librt or something similar. Enabling it when |
2383 | the functionality isn't available is safe, though, althoguh you have |
2495 | the functionality isn't available is safe, though, although you have |
2384 | to make sure you link against any libraries where the \f(CW\*(C`clock_gettime\*(C'\fR |
2496 | to make sure you link against any libraries where the \f(CW\*(C`clock_gettime\*(C'\fR |
2385 | function is hiding in (often \fI\-lrt\fR). |
2497 | function is hiding in (often \fI\-lrt\fR). |
2386 | .IP "\s-1EV_USE_REALTIME\s0" 4 |
2498 | .IP "\s-1EV_USE_REALTIME\s0" 4 |
2387 | .IX Item "EV_USE_REALTIME" |
2499 | .IX Item "EV_USE_REALTIME" |
2388 | If defined to be \f(CW1\fR, libev will try to detect the availability of the |
2500 | If defined to be \f(CW1\fR, libev will try to detect the availability of the |
2389 | realtime clock option at compiletime (and assume its availability at |
2501 | realtime clock option at compiletime (and assume its availability at |
2390 | runtime if successful). Otherwise no use of the realtime clock option will |
2502 | runtime if successful). Otherwise no use of the realtime clock option will |
2391 | be attempted. This effectively replaces \f(CW\*(C`gettimeofday\*(C'\fR by \f(CW\*(C`clock_get |
2503 | be attempted. This effectively replaces \f(CW\*(C`gettimeofday\*(C'\fR by \f(CW\*(C`clock_get |
2392 | (CLOCK_REALTIME, ...)\*(C'\fR and will not normally affect correctness. See tzhe note about libraries |
2504 | (CLOCK_REALTIME, ...)\*(C'\fR and will not normally affect correctness. See the |
2393 | in the description of \f(CW\*(C`EV_USE_MONOTONIC\*(C'\fR, though. |
2505 | note about libraries in the description of \f(CW\*(C`EV_USE_MONOTONIC\*(C'\fR, though. |
2394 | .IP "\s-1EV_USE_SELECT\s0" 4 |
2506 | .IP "\s-1EV_USE_SELECT\s0" 4 |
2395 | .IX Item "EV_USE_SELECT" |
2507 | .IX Item "EV_USE_SELECT" |
2396 | If undefined or defined to be \f(CW1\fR, libev will compile in support for the |
2508 | If undefined or defined to be \f(CW1\fR, libev will compile in support for the |
2397 | \&\f(CW\*(C`select\*(C'\fR(2) backend. No attempt at autodetection will be done: if no |
2509 | \&\f(CW\*(C`select\*(C'\fR(2) backend. No attempt at autodetection will be done: if no |
2398 | other method takes over, select will be it. Otherwise the select backend |
2510 | other method takes over, select will be it. Otherwise the select backend |
… | |
… | |
2558 | .IP "ev_set_cb (ev, cb)" 4 |
2670 | .IP "ev_set_cb (ev, cb)" 4 |
2559 | .IX Item "ev_set_cb (ev, cb)" |
2671 | .IX Item "ev_set_cb (ev, cb)" |
2560 | .PD |
2672 | .PD |
2561 | Can be used to change the callback member declaration in each watcher, |
2673 | Can be used to change the callback member declaration in each watcher, |
2562 | and the way callbacks are invoked and set. Must expand to a struct member |
2674 | and the way callbacks are invoked and set. Must expand to a struct member |
2563 | definition and a statement, respectively. See the \fIev.v\fR header file for |
2675 | definition and a statement, respectively. See the \fIev.h\fR header file for |
2564 | their default definitions. One possible use for overriding these is to |
2676 | their default definitions. One possible use for overriding these is to |
2565 | avoid the \f(CW\*(C`struct ev_loop *\*(C'\fR as first argument in all cases, or to use |
2677 | avoid the \f(CW\*(C`struct ev_loop *\*(C'\fR as first argument in all cases, or to use |
2566 | method calls instead of plain function calls in \*(C+. |
2678 | method calls instead of plain function calls in \*(C+. |
|
|
2679 | .Sh "\s-1EXPORTED\s0 \s-1API\s0 \s-1SYMBOLS\s0" |
|
|
2680 | .IX Subsection "EXPORTED API SYMBOLS" |
|
|
2681 | If you need to re-export the \s-1API\s0 (e.g. via a dll) and you need a list of |
|
|
2682 | exported symbols, you can use the provided \fISymbol.*\fR files which list |
|
|
2683 | all public symbols, one per line: |
|
|
2684 | .Sp |
|
|
2685 | .Vb 2 |
|
|
2686 | \& Symbols.ev for libev proper |
|
|
2687 | \& Symbols.event for the libevent emulation |
|
|
2688 | .Ve |
|
|
2689 | .Sp |
|
|
2690 | This can also be used to rename all public symbols to avoid clashes with |
|
|
2691 | multiple versions of libev linked together (which is obviously bad in |
|
|
2692 | itself, but sometimes it is inconvinient to avoid this). |
|
|
2693 | .Sp |
|
|
2694 | A sed command like this will create wrapper \f(CW\*(C`#define\*(C'\fR's that you need to |
|
|
2695 | include before including \fIev.h\fR: |
|
|
2696 | .Sp |
|
|
2697 | .Vb 1 |
|
|
2698 | \& <Symbols.ev sed -e "s/.*/#define & myprefix_&/" >wrap.h |
|
|
2699 | .Ve |
|
|
2700 | .Sp |
|
|
2701 | This would create a file \fIwrap.h\fR which essentially looks like this: |
|
|
2702 | .Sp |
|
|
2703 | .Vb 4 |
|
|
2704 | \& #define ev_backend myprefix_ev_backend |
|
|
2705 | \& #define ev_check_start myprefix_ev_check_start |
|
|
2706 | \& #define ev_check_stop myprefix_ev_check_stop |
|
|
2707 | \& ... |
|
|
2708 | .Ve |
2567 | .Sh "\s-1EXAMPLES\s0" |
2709 | .Sh "\s-1EXAMPLES\s0" |
2568 | .IX Subsection "EXAMPLES" |
2710 | .IX Subsection "EXAMPLES" |
2569 | For a real-world example of a program the includes libev |
2711 | For a real-world example of a program the includes libev |
2570 | verbatim, you can have a look at the \s-1EV\s0 perl module |
2712 | verbatim, you can have a look at the \s-1EV\s0 perl module |
2571 | (<http://software.schmorp.de/pkg/EV.html>). It has the libev files in |
2713 | (<http://software.schmorp.de/pkg/EV.html>). It has the libev files in |