… | |
… | |
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 "2007-12-08" "perl v5.8.8" "User Contributed Perl Documentation" |
132 | .TH EV 1 "2007-12-18" "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 |
… | |
… | |
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 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 |
|
|
272 | These version numbers refer to the \s-1ABI\s0 version of the library, not the |
|
|
273 | release version. |
|
|
274 | .Sp |
270 | 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, |
271 | as this indicates an incompatible change. Minor versions are usually |
276 | as this indicates an incompatible change. Minor versions are usually |
272 | 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 |
273 | not a problem. |
278 | not a problem. |
274 | .Sp |
279 | .Sp |
275 | Example: Make sure we haven't accidentally been linked against the wrong |
280 | Example: Make sure we haven't accidentally been linked against the wrong |
276 | version. |
281 | version. |
… | |
… | |
552 | Destroys the default loop again (frees all memory and kernel state |
557 | Destroys the default loop again (frees all memory and kernel state |
553 | etc.). None of the active event watchers will be stopped in the normal |
558 | etc.). None of the active event watchers will be stopped in the normal |
554 | sense, so e.g. \f(CW\*(C`ev_is_active\*(C'\fR might still return true. It is your |
559 | sense, so e.g. \f(CW\*(C`ev_is_active\*(C'\fR might still return true. It is your |
555 | responsibility to either stop all watchers cleanly yoursef \fIbefore\fR |
560 | responsibility to either stop all watchers cleanly yoursef \fIbefore\fR |
556 | calling this function, or cope with the fact afterwards (which is usually |
561 | calling this function, or cope with the fact afterwards (which is usually |
557 | the easiest thing, youc na just ignore the watchers and/or \f(CW\*(C`free ()\*(C'\fR them |
562 | the easiest thing, you can just ignore the watchers and/or \f(CW\*(C`free ()\*(C'\fR them |
558 | for example). |
563 | for example). |
|
|
564 | .Sp |
|
|
565 | Not 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) |
|
|
567 | would need to be stopped manually. |
|
|
568 | .Sp |
|
|
569 | 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 |
|
|
571 | pipe fds. If you need dynamically allocated loops it is better to use |
|
|
572 | \&\f(CW\*(C`ev_loop_new\*(C'\fR and \f(CW\*(C`ev_loop_destroy\*(C'\fR). |
559 | .IP "ev_loop_destroy (loop)" 4 |
573 | .IP "ev_loop_destroy (loop)" 4 |
560 | .IX Item "ev_loop_destroy (loop)" |
574 | .IX Item "ev_loop_destroy (loop)" |
561 | Like \f(CW\*(C`ev_default_destroy\*(C'\fR, but destroys an event loop created by an |
575 | Like \f(CW\*(C`ev_default_destroy\*(C'\fR, but destroys an event loop created by an |
562 | earlier call to \f(CW\*(C`ev_loop_new\*(C'\fR. |
576 | earlier call to \f(CW\*(C`ev_loop_new\*(C'\fR. |
563 | .IP "ev_default_fork ()" 4 |
577 | .IP "ev_default_fork ()" 4 |
… | |
… | |
634 | libev watchers. However, a pair of \f(CW\*(C`ev_prepare\*(C'\fR/\f(CW\*(C`ev_check\*(C'\fR watchers is |
648 | libev watchers. However, a pair of \f(CW\*(C`ev_prepare\*(C'\fR/\f(CW\*(C`ev_check\*(C'\fR watchers is |
635 | usually a better approach for this kind of thing. |
649 | usually a better approach for this kind of thing. |
636 | .Sp |
650 | .Sp |
637 | Here are the gory details of what \f(CW\*(C`ev_loop\*(C'\fR does: |
651 | Here are the gory details of what \f(CW\*(C`ev_loop\*(C'\fR does: |
638 | .Sp |
652 | .Sp |
639 | .Vb 18 |
653 | .Vb 19 |
|
|
654 | \& - Before the first iteration, call any pending watchers. |
640 | \& * If there are no active watchers (reference count is zero), return. |
655 | \& * If there are no active watchers (reference count is zero), return. |
641 | \& - Queue prepare watchers and then call all outstanding watchers. |
656 | \& - Queue all prepare watchers and then call all outstanding watchers. |
642 | \& - If we have been forked, recreate the kernel state. |
657 | \& - If we have been forked, recreate the kernel state. |
643 | \& - Update the kernel state with all outstanding changes. |
658 | \& - Update the kernel state with all outstanding changes. |
644 | \& - Update the "event loop time". |
659 | \& - Update the "event loop time". |
645 | \& - Calculate for how long to block. |
660 | \& - Calculate for how long to block. |
646 | \& - Block the process, waiting for any events. |
661 | \& - Block the process, waiting for any events. |
… | |
… | |
1061 | If you cannot run the fd in non-blocking mode (for example you should not |
1076 | If you cannot run the fd in non-blocking mode (for example you should not |
1062 | play around with an Xlib connection), then you have to seperately re-test |
1077 | play around with an Xlib connection), then you have to seperately re-test |
1063 | whether a file descriptor is really ready with a known-to-be good interface |
1078 | whether a file descriptor is really ready with a known-to-be good interface |
1064 | such as poll (fortunately in our Xlib example, Xlib already does this on |
1079 | such as poll (fortunately in our Xlib example, Xlib already does this on |
1065 | its own, so its quite safe to use). |
1080 | its own, so its quite safe to use). |
|
|
1081 | .PP |
|
|
1082 | \fIThe special problem of disappearing file descriptors\fR |
|
|
1083 | .IX Subsection "The special problem of disappearing file descriptors" |
|
|
1084 | .PP |
|
|
1085 | 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, |
|
|
1087 | 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 |
|
|
1089 | 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 |
|
|
1091 | fact, a different file descriptor. |
|
|
1092 | .PP |
|
|
1093 | To avoid having to explicitly tell libev about such cases, libev follows |
|
|
1094 | the following policy: Each time \f(CW\*(C`ev_io_set\*(C'\fR is being called, libev |
|
|
1095 | will assume that this is potentially a new file descriptor, otherwise |
|
|
1096 | it is assumed that the file descriptor stays the same. That means that |
|
|
1097 | 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 |
|
|
1098 | descriptor even if the file descriptor number itself did not change. |
|
|
1099 | .PP |
|
|
1100 | 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 |
|
|
1102 | optimisations to libev. |
|
|
1103 | .PP |
|
|
1104 | \fIWatcher-Specific Functions\fR |
|
|
1105 | .IX Subsection "Watcher-Specific Functions" |
1066 | .IP "ev_io_init (ev_io *, callback, int fd, int events)" 4 |
1106 | .IP "ev_io_init (ev_io *, callback, int fd, int events)" 4 |
1067 | .IX Item "ev_io_init (ev_io *, callback, int fd, int events)" |
1107 | .IX Item "ev_io_init (ev_io *, callback, int fd, int events)" |
1068 | .PD 0 |
1108 | .PD 0 |
1069 | .IP "ev_io_set (ev_io *, int fd, int events)" 4 |
1109 | .IP "ev_io_set (ev_io *, int fd, int events)" 4 |
1070 | .IX Item "ev_io_set (ev_io *, int fd, int events)" |
1110 | .IX Item "ev_io_set (ev_io *, int fd, int events)" |
… | |
… | |
1123 | .Ve |
1163 | .Ve |
1124 | .PP |
1164 | .PP |
1125 | The callback is guarenteed to be invoked only when its timeout has passed, |
1165 | The callback is guarenteed to be invoked only when its timeout has passed, |
1126 | but if multiple timers become ready during the same loop iteration then |
1166 | but if multiple timers become ready during the same loop iteration then |
1127 | order of execution is undefined. |
1167 | order of execution is undefined. |
|
|
1168 | .PP |
|
|
1169 | \fIWatcher-Specific Functions and Data Members\fR |
|
|
1170 | .IX Subsection "Watcher-Specific Functions and Data Members" |
1128 | .IP "ev_timer_init (ev_timer *, callback, ev_tstamp after, ev_tstamp repeat)" 4 |
1171 | .IP "ev_timer_init (ev_timer *, callback, ev_tstamp after, ev_tstamp repeat)" 4 |
1129 | .IX Item "ev_timer_init (ev_timer *, callback, ev_tstamp after, ev_tstamp repeat)" |
1172 | .IX Item "ev_timer_init (ev_timer *, callback, ev_tstamp after, ev_tstamp repeat)" |
1130 | .PD 0 |
1173 | .PD 0 |
1131 | .IP "ev_timer_set (ev_timer *, ev_tstamp after, ev_tstamp repeat)" 4 |
1174 | .IP "ev_timer_set (ev_timer *, ev_tstamp after, ev_tstamp repeat)" 4 |
1132 | .IX Item "ev_timer_set (ev_timer *, ev_tstamp after, ev_tstamp repeat)" |
1175 | .IX Item "ev_timer_set (ev_timer *, ev_tstamp after, ev_tstamp repeat)" |
… | |
… | |
1234 | but on wallclock time (absolute time). You can tell a periodic watcher |
1277 | but on wallclock time (absolute time). You can tell a periodic watcher |
1235 | to trigger \*(L"at\*(R" some specific point in time. For example, if you tell a |
1278 | to trigger \*(L"at\*(R" some specific point in time. For example, if you tell a |
1236 | periodic watcher to trigger in 10 seconds (by specifiying e.g. \f(CW\*(C`ev_now () |
1279 | periodic watcher to trigger in 10 seconds (by specifiying e.g. \f(CW\*(C`ev_now () |
1237 | + 10.\*(C'\fR) and then reset your system clock to the last year, then it will |
1280 | + 10.\*(C'\fR) and then reset your system clock to the last year, then it will |
1238 | take a year to trigger the event (unlike an \f(CW\*(C`ev_timer\*(C'\fR, which would trigger |
1281 | take a year to trigger the event (unlike an \f(CW\*(C`ev_timer\*(C'\fR, which would trigger |
1239 | roughly 10 seconds later and of course not if you reset your system time |
1282 | roughly 10 seconds later). |
1240 | again). |
|
|
1241 | .PP |
1283 | .PP |
1242 | They can also be used to implement vastly more complex timers, such as |
1284 | They can also be used to implement vastly more complex timers, such as |
1243 | triggering an event on eahc midnight, local time. |
1285 | triggering an event on each midnight, local time or other, complicated, |
|
|
1286 | rules. |
1244 | .PP |
1287 | .PP |
1245 | As with timers, the callback is guarenteed to be invoked only when the |
1288 | As with timers, the callback is guarenteed to be invoked only when the |
1246 | time (\f(CW\*(C`at\*(C'\fR) has been passed, but if multiple periodic timers become ready |
1289 | time (\f(CW\*(C`at\*(C'\fR) has been passed, but if multiple periodic timers become ready |
1247 | during the same loop iteration then order of execution is undefined. |
1290 | during the same loop iteration then order of execution is undefined. |
|
|
1291 | .PP |
|
|
1292 | \fIWatcher-Specific Functions and Data Members\fR |
|
|
1293 | .IX Subsection "Watcher-Specific Functions and Data Members" |
1248 | .IP "ev_periodic_init (ev_periodic *, callback, ev_tstamp at, ev_tstamp interval, reschedule_cb)" 4 |
1294 | .IP "ev_periodic_init (ev_periodic *, callback, ev_tstamp at, ev_tstamp interval, reschedule_cb)" 4 |
1249 | .IX Item "ev_periodic_init (ev_periodic *, callback, ev_tstamp at, ev_tstamp interval, reschedule_cb)" |
1295 | .IX Item "ev_periodic_init (ev_periodic *, callback, ev_tstamp at, ev_tstamp interval, reschedule_cb)" |
1250 | .PD 0 |
1296 | .PD 0 |
1251 | .IP "ev_periodic_set (ev_periodic *, ev_tstamp after, ev_tstamp repeat, reschedule_cb)" 4 |
1297 | .IP "ev_periodic_set (ev_periodic *, ev_tstamp after, ev_tstamp repeat, reschedule_cb)" 4 |
1252 | .IX Item "ev_periodic_set (ev_periodic *, ev_tstamp after, ev_tstamp repeat, reschedule_cb)" |
1298 | .IX Item "ev_periodic_set (ev_periodic *, ev_tstamp after, ev_tstamp repeat, reschedule_cb)" |
1253 | .PD |
1299 | .PD |
1254 | Lots of arguments, lets sort it out... There are basically three modes of |
1300 | Lots of arguments, lets sort it out... There are basically three modes of |
1255 | operation, and we will explain them from simplest to complex: |
1301 | operation, and we will explain them from simplest to complex: |
1256 | .RS 4 |
1302 | .RS 4 |
1257 | .IP "* absolute timer (interval = reschedule_cb = 0)" 4 |
1303 | .IP "* absolute timer (at = time, interval = reschedule_cb = 0)" 4 |
1258 | .IX Item "absolute timer (interval = reschedule_cb = 0)" |
1304 | .IX Item "absolute timer (at = time, interval = reschedule_cb = 0)" |
1259 | In this configuration the watcher triggers an event at the wallclock time |
1305 | In this configuration the watcher triggers an event at the wallclock time |
1260 | \&\f(CW\*(C`at\*(C'\fR and doesn't repeat. It will not adjust when a time jump occurs, |
1306 | \&\f(CW\*(C`at\*(C'\fR and doesn't repeat. It will not adjust when a time jump occurs, |
1261 | that is, if it is to be run at January 1st 2011 then it will run when the |
1307 | that is, if it is to be run at January 1st 2011 then it will run when the |
1262 | system time reaches or surpasses this time. |
1308 | system time reaches or surpasses this time. |
1263 | .IP "* non-repeating interval timer (interval > 0, reschedule_cb = 0)" 4 |
1309 | .IP "* non-repeating interval timer (at = offset, interval > 0, reschedule_cb = 0)" 4 |
1264 | .IX Item "non-repeating interval timer (interval > 0, reschedule_cb = 0)" |
1310 | .IX Item "non-repeating interval timer (at = offset, interval > 0, reschedule_cb = 0)" |
1265 | In this mode the watcher will always be scheduled to time out at the next |
1311 | In this mode the watcher will always be scheduled to time out at the next |
1266 | \&\f(CW\*(C`at + N * interval\*(C'\fR time (for some integer N) and then repeat, regardless |
1312 | \&\f(CW\*(C`at + N * interval\*(C'\fR time (for some integer N, which can also be negative) |
1267 | of any time jumps. |
1313 | and then repeat, regardless of any time jumps. |
1268 | .Sp |
1314 | .Sp |
1269 | This can be used to create timers that do not drift with respect to system |
1315 | This can be used to create timers that do not drift with respect to system |
1270 | time: |
1316 | time: |
1271 | .Sp |
1317 | .Sp |
1272 | .Vb 1 |
1318 | .Vb 1 |
… | |
… | |
1279 | by 3600. |
1325 | by 3600. |
1280 | .Sp |
1326 | .Sp |
1281 | Another way to think about it (for the mathematically inclined) is that |
1327 | Another way to think about it (for the mathematically inclined) is that |
1282 | \&\f(CW\*(C`ev_periodic\*(C'\fR will try to run the callback in this mode at the next possible |
1328 | \&\f(CW\*(C`ev_periodic\*(C'\fR will try to run the callback in this mode at the next possible |
1283 | time where \f(CW\*(C`time = at (mod interval)\*(C'\fR, regardless of any time jumps. |
1329 | time where \f(CW\*(C`time = at (mod interval)\*(C'\fR, regardless of any time jumps. |
|
|
1330 | .Sp |
|
|
1331 | For numerical stability it is preferable that the \f(CW\*(C`at\*(C'\fR value is near |
|
|
1332 | \&\f(CW\*(C`ev_now ()\*(C'\fR (the current time), but there is no range requirement for |
|
|
1333 | this value. |
1284 | .IP "* manual reschedule mode (reschedule_cb = callback)" 4 |
1334 | .IP "* manual reschedule mode (at and interval ignored, reschedule_cb = callback)" 4 |
1285 | .IX Item "manual reschedule mode (reschedule_cb = callback)" |
1335 | .IX Item "manual reschedule mode (at and interval ignored, reschedule_cb = callback)" |
1286 | In this mode the values for \f(CW\*(C`interval\*(C'\fR and \f(CW\*(C`at\*(C'\fR are both being |
1336 | In this mode the values for \f(CW\*(C`interval\*(C'\fR and \f(CW\*(C`at\*(C'\fR are both being |
1287 | ignored. Instead, each time the periodic watcher gets scheduled, the |
1337 | ignored. Instead, each time the periodic watcher gets scheduled, the |
1288 | reschedule callback will be called with the watcher as first, and the |
1338 | reschedule callback will be called with the watcher as first, and the |
1289 | current time as second argument. |
1339 | current time as second argument. |
1290 | .Sp |
1340 | .Sp |
1291 | \&\s-1NOTE:\s0 \fIThis callback \s-1MUST\s0 \s-1NOT\s0 stop or destroy any periodic watcher, |
1341 | \&\s-1NOTE:\s0 \fIThis callback \s-1MUST\s0 \s-1NOT\s0 stop or destroy any periodic watcher, |
1292 | ever, or make any event loop modifications\fR. If you need to stop it, |
1342 | ever, or make any event loop modifications\fR. If you need to stop it, |
1293 | return \f(CW\*(C`now + 1e30\*(C'\fR (or so, fudge fudge) and stop it afterwards (e.g. by |
1343 | return \f(CW\*(C`now + 1e30\*(C'\fR (or so, fudge fudge) and stop it afterwards (e.g. by |
1294 | starting a prepare watcher). |
1344 | starting an \f(CW\*(C`ev_prepare\*(C'\fR watcher, which is legal). |
1295 | .Sp |
1345 | .Sp |
1296 | Its prototype is \f(CW\*(C`ev_tstamp (*reschedule_cb)(struct ev_periodic *w, |
1346 | Its prototype is \f(CW\*(C`ev_tstamp (*reschedule_cb)(struct ev_periodic *w, |
1297 | ev_tstamp now)\*(C'\fR, e.g.: |
1347 | ev_tstamp now)\*(C'\fR, e.g.: |
1298 | .Sp |
1348 | .Sp |
1299 | .Vb 4 |
1349 | .Vb 4 |
… | |
… | |
1323 | .IX Item "ev_periodic_again (loop, ev_periodic *)" |
1373 | .IX Item "ev_periodic_again (loop, ev_periodic *)" |
1324 | Simply stops and restarts the periodic watcher again. This is only useful |
1374 | Simply stops and restarts the periodic watcher again. This is only useful |
1325 | when you changed some parameters or the reschedule callback would return |
1375 | when you changed some parameters or the reschedule callback would return |
1326 | a different time than the last time it was called (e.g. in a crond like |
1376 | a different time than the last time it was called (e.g. in a crond like |
1327 | program when the crontabs have changed). |
1377 | program when the crontabs have changed). |
|
|
1378 | .IP "ev_tstamp offset [read\-write]" 4 |
|
|
1379 | .IX Item "ev_tstamp offset [read-write]" |
|
|
1380 | When repeating, this contains the offset value, otherwise this is the |
|
|
1381 | absolute point in time (the \f(CW\*(C`at\*(C'\fR value passed to \f(CW\*(C`ev_periodic_set\*(C'\fR). |
|
|
1382 | .Sp |
|
|
1383 | Can be modified any time, but changes only take effect when the periodic |
|
|
1384 | timer fires or \f(CW\*(C`ev_periodic_again\*(C'\fR is being called. |
1328 | .IP "ev_tstamp interval [read\-write]" 4 |
1385 | .IP "ev_tstamp interval [read\-write]" 4 |
1329 | .IX Item "ev_tstamp interval [read-write]" |
1386 | .IX Item "ev_tstamp interval [read-write]" |
1330 | The current interval value. Can be modified any time, but changes only |
1387 | The current interval value. Can be modified any time, but changes only |
1331 | take effect when the periodic timer fires or \f(CW\*(C`ev_periodic_again\*(C'\fR is being |
1388 | take effect when the periodic timer fires or \f(CW\*(C`ev_periodic_again\*(C'\fR is being |
1332 | called. |
1389 | called. |
1333 | .IP "ev_tstamp (*reschedule_cb)(struct ev_periodic *w, ev_tstamp now) [read\-write]" 4 |
1390 | .IP "ev_tstamp (*reschedule_cb)(struct ev_periodic *w, ev_tstamp now) [read\-write]" 4 |
1334 | .IX Item "ev_tstamp (*reschedule_cb)(struct ev_periodic *w, ev_tstamp now) [read-write]" |
1391 | .IX Item "ev_tstamp (*reschedule_cb)(struct ev_periodic *w, ev_tstamp now) [read-write]" |
1335 | The current reschedule callback, or \f(CW0\fR, if this functionality is |
1392 | The current reschedule callback, or \f(CW0\fR, if this functionality is |
1336 | switched off. Can be changed any time, but changes only take effect when |
1393 | switched off. Can be changed any time, but changes only take effect when |
1337 | the periodic timer fires or \f(CW\*(C`ev_periodic_again\*(C'\fR is being called. |
1394 | the periodic timer fires or \f(CW\*(C`ev_periodic_again\*(C'\fR is being called. |
|
|
1395 | .IP "ev_tstamp at [read\-only]" 4 |
|
|
1396 | .IX Item "ev_tstamp at [read-only]" |
|
|
1397 | When active, contains the absolute time that the watcher is supposed to |
|
|
1398 | trigger next. |
1338 | .PP |
1399 | .PP |
1339 | Example: Call a callback every hour, or, more precisely, whenever the |
1400 | Example: Call a callback every hour, or, more precisely, whenever the |
1340 | system clock is divisible by 3600. The callback invocation times have |
1401 | system clock is divisible by 3600. The callback invocation times have |
1341 | potentially a lot of jittering, but good long-term stability. |
1402 | potentially a lot of jittering, but good long-term stability. |
1342 | .PP |
1403 | .PP |
… | |
… | |
1392 | first watcher gets started will libev actually register a signal watcher |
1453 | first watcher gets started will libev actually register a signal watcher |
1393 | with the kernel (thus it coexists with your own signal handlers as long |
1454 | with the kernel (thus it coexists with your own signal handlers as long |
1394 | as you don't register any with libev). Similarly, when the last signal |
1455 | as you don't register any with libev). Similarly, when the last signal |
1395 | watcher for a signal is stopped libev will reset the signal handler to |
1456 | watcher for a signal is stopped libev will reset the signal handler to |
1396 | \&\s-1SIG_DFL\s0 (regardless of what it was set to before). |
1457 | \&\s-1SIG_DFL\s0 (regardless of what it was set to before). |
|
|
1458 | .PP |
|
|
1459 | \fIWatcher-Specific Functions and Data Members\fR |
|
|
1460 | .IX Subsection "Watcher-Specific Functions and Data Members" |
1397 | .IP "ev_signal_init (ev_signal *, callback, int signum)" 4 |
1461 | .IP "ev_signal_init (ev_signal *, callback, int signum)" 4 |
1398 | .IX Item "ev_signal_init (ev_signal *, callback, int signum)" |
1462 | .IX Item "ev_signal_init (ev_signal *, callback, int signum)" |
1399 | .PD 0 |
1463 | .PD 0 |
1400 | .IP "ev_signal_set (ev_signal *, int signum)" 4 |
1464 | .IP "ev_signal_set (ev_signal *, int signum)" 4 |
1401 | .IX Item "ev_signal_set (ev_signal *, int signum)" |
1465 | .IX Item "ev_signal_set (ev_signal *, int signum)" |
… | |
… | |
1408 | .ie n .Sh """ev_child"" \- watch out for process status changes" |
1472 | .ie n .Sh """ev_child"" \- watch out for process status changes" |
1409 | .el .Sh "\f(CWev_child\fP \- watch out for process status changes" |
1473 | .el .Sh "\f(CWev_child\fP \- watch out for process status changes" |
1410 | .IX Subsection "ev_child - watch out for process status changes" |
1474 | .IX Subsection "ev_child - watch out for process status changes" |
1411 | Child watchers trigger when your process receives a \s-1SIGCHLD\s0 in response to |
1475 | Child watchers trigger when your process receives a \s-1SIGCHLD\s0 in response to |
1412 | some child status changes (most typically when a child of yours dies). |
1476 | some child status changes (most typically when a child of yours dies). |
|
|
1477 | .PP |
|
|
1478 | \fIWatcher-Specific Functions and Data Members\fR |
|
|
1479 | .IX Subsection "Watcher-Specific Functions and Data Members" |
1413 | .IP "ev_child_init (ev_child *, callback, int pid)" 4 |
1480 | .IP "ev_child_init (ev_child *, callback, int pid)" 4 |
1414 | .IX Item "ev_child_init (ev_child *, callback, int pid)" |
1481 | .IX Item "ev_child_init (ev_child *, callback, int pid)" |
1415 | .PD 0 |
1482 | .PD 0 |
1416 | .IP "ev_child_set (ev_child *, int pid)" 4 |
1483 | .IP "ev_child_set (ev_child *, int pid)" 4 |
1417 | .IX Item "ev_child_set (ev_child *, int pid)" |
1484 | .IX Item "ev_child_set (ev_child *, int pid)" |
… | |
… | |
1482 | reader). Inotify will be used to give hints only and should not change the |
1549 | reader). Inotify will be used to give hints only and should not change the |
1483 | semantics of \f(CW\*(C`ev_stat\*(C'\fR watchers, which means that libev sometimes needs |
1550 | semantics of \f(CW\*(C`ev_stat\*(C'\fR watchers, which means that libev sometimes needs |
1484 | to fall back to regular polling again even with inotify, but changes are |
1551 | to fall back to regular polling again even with inotify, but changes are |
1485 | usually detected immediately, and if the file exists there will be no |
1552 | usually detected immediately, and if the file exists there will be no |
1486 | polling. |
1553 | polling. |
|
|
1554 | .PP |
|
|
1555 | \fIWatcher-Specific Functions and Data Members\fR |
|
|
1556 | .IX Subsection "Watcher-Specific Functions and Data Members" |
1487 | .IP "ev_stat_init (ev_stat *, callback, const char *path, ev_tstamp interval)" 4 |
1557 | .IP "ev_stat_init (ev_stat *, callback, const char *path, ev_tstamp interval)" 4 |
1488 | .IX Item "ev_stat_init (ev_stat *, callback, const char *path, ev_tstamp interval)" |
1558 | .IX Item "ev_stat_init (ev_stat *, callback, const char *path, ev_tstamp interval)" |
1489 | .PD 0 |
1559 | .PD 0 |
1490 | .IP "ev_stat_set (ev_stat *, const char *path, ev_tstamp interval)" 4 |
1560 | .IP "ev_stat_set (ev_stat *, const char *path, ev_tstamp interval)" 4 |
1491 | .IX Item "ev_stat_set (ev_stat *, const char *path, ev_tstamp interval)" |
1561 | .IX Item "ev_stat_set (ev_stat *, const char *path, ev_tstamp interval)" |
… | |
… | |
1570 | .PP |
1640 | .PP |
1571 | Apart from keeping your process non-blocking (which is a useful |
1641 | Apart from keeping your process non-blocking (which is a useful |
1572 | effect on its own sometimes), idle watchers are a good place to do |
1642 | effect on its own sometimes), idle watchers are a good place to do |
1573 | \&\*(L"pseudo\-background processing\*(R", or delay processing stuff to after the |
1643 | \&\*(L"pseudo\-background processing\*(R", or delay processing stuff to after the |
1574 | event loop has handled all outstanding events. |
1644 | event loop has handled all outstanding events. |
|
|
1645 | .PP |
|
|
1646 | \fIWatcher-Specific Functions and Data Members\fR |
|
|
1647 | .IX Subsection "Watcher-Specific Functions and Data Members" |
1575 | .IP "ev_idle_init (ev_signal *, callback)" 4 |
1648 | .IP "ev_idle_init (ev_signal *, callback)" 4 |
1576 | .IX Item "ev_idle_init (ev_signal *, callback)" |
1649 | .IX Item "ev_idle_init (ev_signal *, callback)" |
1577 | Initialises and configures the idle watcher \- it has no parameters of any |
1650 | Initialises and configures the idle watcher \- it has no parameters of any |
1578 | kind. There is a \f(CW\*(C`ev_idle_set\*(C'\fR macro, but using it is utterly pointless, |
1651 | kind. There is a \f(CW\*(C`ev_idle_set\*(C'\fR macro, but using it is utterly pointless, |
1579 | believe me. |
1652 | believe me. |
… | |
… | |
1634 | are ready to run (it's actually more complicated: it only runs coroutines |
1707 | are ready to run (it's actually more complicated: it only runs coroutines |
1635 | with priority higher than or equal to the event loop and one coroutine |
1708 | with priority higher than or equal to the event loop and one coroutine |
1636 | of lower priority, but only once, using idle watchers to keep the event |
1709 | of lower priority, but only once, using idle watchers to keep the event |
1637 | loop from blocking if lower-priority coroutines are active, thus mapping |
1710 | loop from blocking if lower-priority coroutines are active, thus mapping |
1638 | low-priority coroutines to idle/background tasks). |
1711 | low-priority coroutines to idle/background tasks). |
|
|
1712 | .PP |
|
|
1713 | It is recommended to give \f(CW\*(C`ev_check\*(C'\fR watchers highest (\f(CW\*(C`EV_MAXPRI\*(C'\fR) |
|
|
1714 | priority, to ensure that they are being run before any other watchers |
|
|
1715 | after the poll. Also, \f(CW\*(C`ev_check\*(C'\fR watchers (and \f(CW\*(C`ev_prepare\*(C'\fR watchers, |
|
|
1716 | too) should not activate (\*(L"feed\*(R") events into libev. While libev fully |
|
|
1717 | supports this, they will be called before other \f(CW\*(C`ev_check\*(C'\fR watchers did |
|
|
1718 | their job. As \f(CW\*(C`ev_check\*(C'\fR watchers are often used to embed other event |
|
|
1719 | loops those other event loops might be in an unusable state until their |
|
|
1720 | \&\f(CW\*(C`ev_check\*(C'\fR watcher ran (always remind yourself to coexist peacefully with |
|
|
1721 | others). |
|
|
1722 | .PP |
|
|
1723 | \fIWatcher-Specific Functions and Data Members\fR |
|
|
1724 | .IX Subsection "Watcher-Specific Functions and Data Members" |
1639 | .IP "ev_prepare_init (ev_prepare *, callback)" 4 |
1725 | .IP "ev_prepare_init (ev_prepare *, callback)" 4 |
1640 | .IX Item "ev_prepare_init (ev_prepare *, callback)" |
1726 | .IX Item "ev_prepare_init (ev_prepare *, callback)" |
1641 | .PD 0 |
1727 | .PD 0 |
1642 | .IP "ev_check_init (ev_check *, callback)" 4 |
1728 | .IP "ev_check_init (ev_check *, callback)" 4 |
1643 | .IX Item "ev_check_init (ev_check *, callback)" |
1729 | .IX Item "ev_check_init (ev_check *, callback)" |
1644 | .PD |
1730 | .PD |
1645 | Initialises and configures the prepare or check watcher \- they have no |
1731 | Initialises and configures the prepare or check watcher \- they have no |
1646 | parameters of any kind. There are \f(CW\*(C`ev_prepare_set\*(C'\fR and \f(CW\*(C`ev_check_set\*(C'\fR |
1732 | parameters of any kind. There are \f(CW\*(C`ev_prepare_set\*(C'\fR and \f(CW\*(C`ev_check_set\*(C'\fR |
1647 | macros, but using them is utterly, utterly and completely pointless. |
1733 | macros, but using them is utterly, utterly and completely pointless. |
1648 | .PP |
1734 | .PP |
1649 | Example: To include a library such as adns, you would add \s-1IO\s0 watchers |
1735 | There are a number of principal ways to embed other event loops or modules |
1650 | and a timeout watcher in a prepare handler, as required by libadns, and |
1736 | into libev. Here are some ideas on how to include libadns into libev |
|
|
1737 | (there is a Perl module named \f(CW\*(C`EV::ADNS\*(C'\fR that does this, which you could |
|
|
1738 | use for an actually working example. Another Perl module named \f(CW\*(C`EV::Glib\*(C'\fR |
|
|
1739 | embeds a Glib main context into libev, and finally, \f(CW\*(C`Glib::EV\*(C'\fR embeds \s-1EV\s0 |
|
|
1740 | into the Glib event loop). |
|
|
1741 | .PP |
|
|
1742 | Method 1: Add \s-1IO\s0 watchers and a timeout watcher in a prepare handler, |
1651 | in a check watcher, destroy them and call into libadns. What follows is |
1743 | and in a check watcher, destroy them and call into libadns. What follows |
1652 | pseudo-code only of course: |
1744 | is pseudo-code only of course. This requires you to either use a low |
|
|
1745 | priority for the check watcher or use \f(CW\*(C`ev_clear_pending\*(C'\fR explicitly, as |
|
|
1746 | the callbacks for the IO/timeout watchers might not have been called yet. |
1653 | .PP |
1747 | .PP |
1654 | .Vb 2 |
1748 | .Vb 2 |
1655 | \& static ev_io iow [nfd]; |
1749 | \& static ev_io iow [nfd]; |
1656 | \& static ev_timer tw; |
1750 | \& static ev_timer tw; |
1657 | .Ve |
1751 | .Ve |
1658 | .PP |
1752 | .PP |
1659 | .Vb 9 |
1753 | .Vb 4 |
1660 | \& static void |
1754 | \& static void |
1661 | \& io_cb (ev_loop *loop, ev_io *w, int revents) |
1755 | \& io_cb (ev_loop *loop, ev_io *w, int revents) |
1662 | \& { |
1756 | \& { |
1663 | \& // set the relevant poll flags |
|
|
1664 | \& // could also call adns_processreadable etc. here |
|
|
1665 | \& struct pollfd *fd = (struct pollfd *)w->data; |
|
|
1666 | \& if (revents & EV_READ ) fd->revents |= fd->events & POLLIN; |
|
|
1667 | \& if (revents & EV_WRITE) fd->revents |= fd->events & POLLOUT; |
|
|
1668 | \& } |
1757 | \& } |
1669 | .Ve |
1758 | .Ve |
1670 | .PP |
1759 | .PP |
1671 | .Vb 8 |
1760 | .Vb 8 |
1672 | \& // create io watchers for each fd and a timer before blocking |
1761 | \& // create io watchers for each fd and a timer before blocking |
… | |
… | |
1684 | \& ev_timer_init (&tw, 0, timeout * 1e-3); |
1773 | \& ev_timer_init (&tw, 0, timeout * 1e-3); |
1685 | \& ev_timer_start (loop, &tw); |
1774 | \& ev_timer_start (loop, &tw); |
1686 | .Ve |
1775 | .Ve |
1687 | .PP |
1776 | .PP |
1688 | .Vb 6 |
1777 | .Vb 6 |
1689 | \& // create on ev_io per pollfd |
1778 | \& // create one ev_io per pollfd |
1690 | \& for (int i = 0; i < nfd; ++i) |
1779 | \& for (int i = 0; i < nfd; ++i) |
1691 | \& { |
1780 | \& { |
1692 | \& ev_io_init (iow + i, io_cb, fds [i].fd, |
1781 | \& ev_io_init (iow + i, io_cb, fds [i].fd, |
1693 | \& ((fds [i].events & POLLIN ? EV_READ : 0) |
1782 | \& ((fds [i].events & POLLIN ? EV_READ : 0) |
1694 | \& | (fds [i].events & POLLOUT ? EV_WRITE : 0))); |
1783 | \& | (fds [i].events & POLLOUT ? EV_WRITE : 0))); |
1695 | .Ve |
1784 | .Ve |
1696 | .PP |
1785 | .PP |
1697 | .Vb 5 |
1786 | .Vb 4 |
1698 | \& fds [i].revents = 0; |
1787 | \& fds [i].revents = 0; |
1699 | \& iow [i].data = fds + i; |
|
|
1700 | \& ev_io_start (loop, iow + i); |
1788 | \& ev_io_start (loop, iow + i); |
1701 | \& } |
1789 | \& } |
1702 | \& } |
1790 | \& } |
1703 | .Ve |
1791 | .Ve |
1704 | .PP |
1792 | .PP |
… | |
… | |
1708 | \& adns_check_cb (ev_loop *loop, ev_check *w, int revents) |
1796 | \& adns_check_cb (ev_loop *loop, ev_check *w, int revents) |
1709 | \& { |
1797 | \& { |
1710 | \& ev_timer_stop (loop, &tw); |
1798 | \& ev_timer_stop (loop, &tw); |
1711 | .Ve |
1799 | .Ve |
1712 | .PP |
1800 | .PP |
1713 | .Vb 2 |
1801 | .Vb 8 |
1714 | \& for (int i = 0; i < nfd; ++i) |
1802 | \& for (int i = 0; i < nfd; ++i) |
|
|
1803 | \& { |
|
|
1804 | \& // set the relevant poll flags |
|
|
1805 | \& // could also call adns_processreadable etc. here |
|
|
1806 | \& struct pollfd *fd = fds + i; |
|
|
1807 | \& int revents = ev_clear_pending (iow + i); |
|
|
1808 | \& if (revents & EV_READ ) fd->revents |= fd->events & POLLIN; |
|
|
1809 | \& if (revents & EV_WRITE) fd->revents |= fd->events & POLLOUT; |
|
|
1810 | .Ve |
|
|
1811 | .PP |
|
|
1812 | .Vb 3 |
|
|
1813 | \& // now stop the watcher |
1715 | \& ev_io_stop (loop, iow + i); |
1814 | \& ev_io_stop (loop, iow + i); |
|
|
1815 | \& } |
1716 | .Ve |
1816 | .Ve |
1717 | .PP |
1817 | .PP |
1718 | .Vb 2 |
1818 | .Vb 2 |
1719 | \& adns_afterpoll (adns, fds, nfd, timeval_from (ev_now (loop)); |
1819 | \& adns_afterpoll (adns, fds, nfd, timeval_from (ev_now (loop)); |
|
|
1820 | \& } |
|
|
1821 | .Ve |
|
|
1822 | .PP |
|
|
1823 | Method 2: This would be just like method 1, but you run \f(CW\*(C`adns_afterpoll\*(C'\fR |
|
|
1824 | in the prepare watcher and would dispose of the check watcher. |
|
|
1825 | .PP |
|
|
1826 | Method 3: If the module to be embedded supports explicit event |
|
|
1827 | notification (adns does), you can also make use of the actual watcher |
|
|
1828 | callbacks, and only destroy/create the watchers in the prepare watcher. |
|
|
1829 | .PP |
|
|
1830 | .Vb 5 |
|
|
1831 | \& static void |
|
|
1832 | \& timer_cb (EV_P_ ev_timer *w, int revents) |
|
|
1833 | \& { |
|
|
1834 | \& adns_state ads = (adns_state)w->data; |
|
|
1835 | \& update_now (EV_A); |
|
|
1836 | .Ve |
|
|
1837 | .PP |
|
|
1838 | .Vb 2 |
|
|
1839 | \& adns_processtimeouts (ads, &tv_now); |
|
|
1840 | \& } |
|
|
1841 | .Ve |
|
|
1842 | .PP |
|
|
1843 | .Vb 5 |
|
|
1844 | \& static void |
|
|
1845 | \& io_cb (EV_P_ ev_io *w, int revents) |
|
|
1846 | \& { |
|
|
1847 | \& adns_state ads = (adns_state)w->data; |
|
|
1848 | \& update_now (EV_A); |
|
|
1849 | .Ve |
|
|
1850 | .PP |
|
|
1851 | .Vb 3 |
|
|
1852 | \& if (revents & EV_READ ) adns_processreadable (ads, w->fd, &tv_now); |
|
|
1853 | \& if (revents & EV_WRITE) adns_processwriteable (ads, w->fd, &tv_now); |
|
|
1854 | \& } |
|
|
1855 | .Ve |
|
|
1856 | .PP |
|
|
1857 | .Vb 1 |
|
|
1858 | \& // do not ever call adns_afterpoll |
|
|
1859 | .Ve |
|
|
1860 | .PP |
|
|
1861 | Method 4: Do not use a prepare or check watcher because the module you |
|
|
1862 | want to embed is too inflexible to support it. Instead, youc na override |
|
|
1863 | their poll function. The drawback with this solution is that the main |
|
|
1864 | loop is now no longer controllable by \s-1EV\s0. The \f(CW\*(C`Glib::EV\*(C'\fR module does |
|
|
1865 | this. |
|
|
1866 | .PP |
|
|
1867 | .Vb 4 |
|
|
1868 | \& static gint |
|
|
1869 | \& event_poll_func (GPollFD *fds, guint nfds, gint timeout) |
|
|
1870 | \& { |
|
|
1871 | \& int got_events = 0; |
|
|
1872 | .Ve |
|
|
1873 | .PP |
|
|
1874 | .Vb 2 |
|
|
1875 | \& for (n = 0; n < nfds; ++n) |
|
|
1876 | \& // create/start io watcher that sets the relevant bits in fds[n] and increment got_events |
|
|
1877 | .Ve |
|
|
1878 | .PP |
|
|
1879 | .Vb 2 |
|
|
1880 | \& if (timeout >= 0) |
|
|
1881 | \& // create/start timer |
|
|
1882 | .Ve |
|
|
1883 | .PP |
|
|
1884 | .Vb 2 |
|
|
1885 | \& // poll |
|
|
1886 | \& ev_loop (EV_A_ 0); |
|
|
1887 | .Ve |
|
|
1888 | .PP |
|
|
1889 | .Vb 3 |
|
|
1890 | \& // stop timer again |
|
|
1891 | \& if (timeout >= 0) |
|
|
1892 | \& ev_timer_stop (EV_A_ &to); |
|
|
1893 | .Ve |
|
|
1894 | .PP |
|
|
1895 | .Vb 3 |
|
|
1896 | \& // stop io watchers again - their callbacks should have set |
|
|
1897 | \& for (n = 0; n < nfds; ++n) |
|
|
1898 | \& ev_io_stop (EV_A_ iow [n]); |
|
|
1899 | .Ve |
|
|
1900 | .PP |
|
|
1901 | .Vb 2 |
|
|
1902 | \& return got_events; |
1720 | \& } |
1903 | \& } |
1721 | .Ve |
1904 | .Ve |
1722 | .ie n .Sh """ev_embed"" \- when one backend isn't enough..." |
1905 | .ie n .Sh """ev_embed"" \- when one backend isn't enough..." |
1723 | .el .Sh "\f(CWev_embed\fP \- when one backend isn't enough..." |
1906 | .el .Sh "\f(CWev_embed\fP \- when one backend isn't enough..." |
1724 | .IX Subsection "ev_embed - when one backend isn't enough..." |
1907 | .IX Subsection "ev_embed - when one backend isn't enough..." |
… | |
… | |
1793 | \& ev_embed_start (loop_hi, &embed); |
1976 | \& ev_embed_start (loop_hi, &embed); |
1794 | \& } |
1977 | \& } |
1795 | \& else |
1978 | \& else |
1796 | \& loop_lo = loop_hi; |
1979 | \& loop_lo = loop_hi; |
1797 | .Ve |
1980 | .Ve |
|
|
1981 | .PP |
|
|
1982 | \fIWatcher-Specific Functions and Data Members\fR |
|
|
1983 | .IX Subsection "Watcher-Specific Functions and Data Members" |
1798 | .IP "ev_embed_init (ev_embed *, callback, struct ev_loop *embedded_loop)" 4 |
1984 | .IP "ev_embed_init (ev_embed *, callback, struct ev_loop *embedded_loop)" 4 |
1799 | .IX Item "ev_embed_init (ev_embed *, callback, struct ev_loop *embedded_loop)" |
1985 | .IX Item "ev_embed_init (ev_embed *, callback, struct ev_loop *embedded_loop)" |
1800 | .PD 0 |
1986 | .PD 0 |
1801 | .IP "ev_embed_set (ev_embed *, callback, struct ev_loop *embedded_loop)" 4 |
1987 | .IP "ev_embed_set (ev_embed *, callback, struct ev_loop *embedded_loop)" 4 |
1802 | .IX Item "ev_embed_set (ev_embed *, callback, struct ev_loop *embedded_loop)" |
1988 | .IX Item "ev_embed_set (ev_embed *, callback, struct ev_loop *embedded_loop)" |
… | |
… | |
1822 | \&\f(CW\*(C`ev_default_fork\*(C'\fR or \f(CW\*(C`ev_loop_fork\*(C'\fR). The invocation is done before the |
2008 | \&\f(CW\*(C`ev_default_fork\*(C'\fR or \f(CW\*(C`ev_loop_fork\*(C'\fR). The invocation is done before the |
1823 | event loop blocks next and before \f(CW\*(C`ev_check\*(C'\fR watchers are being called, |
2009 | event loop blocks next and before \f(CW\*(C`ev_check\*(C'\fR watchers are being called, |
1824 | and only in the child after the fork. If whoever good citizen calling |
2010 | and only in the child after the fork. If whoever good citizen calling |
1825 | \&\f(CW\*(C`ev_default_fork\*(C'\fR cheats and calls it in the wrong process, the fork |
2011 | \&\f(CW\*(C`ev_default_fork\*(C'\fR cheats and calls it in the wrong process, the fork |
1826 | handlers will be invoked, too, of course. |
2012 | handlers will be invoked, too, of course. |
|
|
2013 | .PP |
|
|
2014 | \fIWatcher-Specific Functions and Data Members\fR |
|
|
2015 | .IX Subsection "Watcher-Specific Functions and Data Members" |
1827 | .IP "ev_fork_init (ev_signal *, callback)" 4 |
2016 | .IP "ev_fork_init (ev_signal *, callback)" 4 |
1828 | .IX Item "ev_fork_init (ev_signal *, callback)" |
2017 | .IX Item "ev_fork_init (ev_signal *, callback)" |
1829 | Initialises and configures the fork watcher \- it has no parameters of any |
2018 | Initialises and configures the fork watcher \- it has no parameters of any |
1830 | kind. There is a \f(CW\*(C`ev_fork_set\*(C'\fR macro, but using it is utterly pointless, |
2019 | kind. There is a \f(CW\*(C`ev_fork_set\*(C'\fR macro, but using it is utterly pointless, |
1831 | believe me. |
2020 | believe me. |
… | |
… | |
2025 | Starts the watcher. Note that there is no \f(CW\*(C`loop\*(C'\fR argument, as the |
2214 | Starts the watcher. Note that there is no \f(CW\*(C`loop\*(C'\fR argument, as the |
2026 | constructor already stores the event loop. |
2215 | constructor already stores the event loop. |
2027 | .IP "w\->stop ()" 4 |
2216 | .IP "w\->stop ()" 4 |
2028 | .IX Item "w->stop ()" |
2217 | .IX Item "w->stop ()" |
2029 | Stops the watcher if it is active. Again, no \f(CW\*(C`loop\*(C'\fR argument. |
2218 | Stops the watcher if it is active. Again, no \f(CW\*(C`loop\*(C'\fR argument. |
2030 | .ie n .IP "w\->again () ""ev::timer""\fR, \f(CW""ev::periodic"" only" 4 |
2219 | .ie n .IP "w\->again () (""ev::timer""\fR, \f(CW""ev::periodic"" only)" 4 |
2031 | .el .IP "w\->again () \f(CWev::timer\fR, \f(CWev::periodic\fR only" 4 |
2220 | .el .IP "w\->again () (\f(CWev::timer\fR, \f(CWev::periodic\fR only)" 4 |
2032 | .IX Item "w->again () ev::timer, ev::periodic only" |
2221 | .IX Item "w->again () (ev::timer, ev::periodic only)" |
2033 | For \f(CW\*(C`ev::timer\*(C'\fR and \f(CW\*(C`ev::periodic\*(C'\fR, this invokes the corresponding |
2222 | For \f(CW\*(C`ev::timer\*(C'\fR and \f(CW\*(C`ev::periodic\*(C'\fR, this invokes the corresponding |
2034 | \&\f(CW\*(C`ev_TYPE_again\*(C'\fR function. |
2223 | \&\f(CW\*(C`ev_TYPE_again\*(C'\fR function. |
2035 | .ie n .IP "w\->sweep () ""ev::embed"" only" 4 |
2224 | .ie n .IP "w\->sweep () (""ev::embed"" only)" 4 |
2036 | .el .IP "w\->sweep () \f(CWev::embed\fR only" 4 |
2225 | .el .IP "w\->sweep () (\f(CWev::embed\fR only)" 4 |
2037 | .IX Item "w->sweep () ev::embed only" |
2226 | .IX Item "w->sweep () (ev::embed only)" |
2038 | Invokes \f(CW\*(C`ev_embed_sweep\*(C'\fR. |
2227 | Invokes \f(CW\*(C`ev_embed_sweep\*(C'\fR. |
2039 | .ie n .IP "w\->update () ""ev::stat"" only" 4 |
2228 | .ie n .IP "w\->update () (""ev::stat"" only)" 4 |
2040 | .el .IP "w\->update () \f(CWev::stat\fR only" 4 |
2229 | .el .IP "w\->update () (\f(CWev::stat\fR only)" 4 |
2041 | .IX Item "w->update () ev::stat only" |
2230 | .IX Item "w->update () (ev::stat only)" |
2042 | Invokes \f(CW\*(C`ev_stat_stat\*(C'\fR. |
2231 | Invokes \f(CW\*(C`ev_stat_stat\*(C'\fR. |
2043 | .RE |
2232 | .RE |
2044 | .RS 4 |
2233 | .RS 4 |
2045 | .RE |
2234 | .RE |
2046 | .PP |
2235 | .PP |
… | |
… | |
2070 | \& io.start (fd, ev::READ); |
2259 | \& io.start (fd, ev::READ); |
2071 | \& } |
2260 | \& } |
2072 | .Ve |
2261 | .Ve |
2073 | .SH "MACRO MAGIC" |
2262 | .SH "MACRO MAGIC" |
2074 | .IX Header "MACRO MAGIC" |
2263 | .IX Header "MACRO MAGIC" |
2075 | Libev can be compiled with a variety of options, the most fundemantal is |
2264 | Libev can be compiled with a variety of options, the most fundamantal |
2076 | \&\f(CW\*(C`EV_MULTIPLICITY\*(C'\fR. This option determines whether (most) functions and |
2265 | of which is \f(CW\*(C`EV_MULTIPLICITY\*(C'\fR. This option determines whether (most) |
2077 | callbacks have an initial \f(CW\*(C`struct ev_loop *\*(C'\fR argument. |
2266 | functions and callbacks have an initial \f(CW\*(C`struct ev_loop *\*(C'\fR argument. |
2078 | .PP |
2267 | .PP |
2079 | To make it easier to write programs that cope with either variant, the |
2268 | To make it easier to write programs that cope with either variant, the |
2080 | following macros are defined: |
2269 | following macros are defined: |
2081 | .ie n .IP """EV_A""\fR, \f(CW""EV_A_""" 4 |
2270 | .ie n .IP """EV_A""\fR, \f(CW""EV_A_""" 4 |
2082 | .el .IP "\f(CWEV_A\fR, \f(CWEV_A_\fR" 4 |
2271 | .el .IP "\f(CWEV_A\fR, \f(CWEV_A_\fR" 4 |