… | |
… | |
127 | .\} |
127 | .\} |
128 | .rm #[ #] #H #V #F C |
128 | .rm #[ #] #H #V #F C |
129 | .\" ======================================================================== |
129 | .\" ======================================================================== |
130 | .\" |
130 | .\" |
131 | .IX Title ""<STANDARD INPUT>" 1" |
131 | .IX Title ""<STANDARD INPUT>" 1" |
132 | .TH "<STANDARD INPUT>" 1 "2007-11-23" "perl v5.8.8" "User Contributed Perl Documentation" |
132 | .TH "<STANDARD INPUT>" 1 "2007-11-24" "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 |
… | |
… | |
231 | recommended for this platform. This set is often smaller than the one |
231 | recommended for this platform. This set is often smaller than the one |
232 | returned by \f(CW\*(C`ev_supported_backends\*(C'\fR, as for example kqueue is broken on |
232 | returned by \f(CW\*(C`ev_supported_backends\*(C'\fR, as for example kqueue is broken on |
233 | most BSDs and will not be autodetected unless you explicitly request it |
233 | most BSDs and will not be autodetected unless you explicitly request it |
234 | (assuming you know what you are doing). This is the set of backends that |
234 | (assuming you know what you are doing). This is the set of backends that |
235 | libev will probe for if you specify no backends explicitly. |
235 | libev will probe for if you specify no backends explicitly. |
|
|
236 | .IP "unsigned int ev_embeddable_backends ()" 4 |
|
|
237 | .IX Item "unsigned int ev_embeddable_backends ()" |
|
|
238 | Returns the set of backends that are embeddable in other event loops. This |
|
|
239 | is the theoretical, all\-platform, value. To find which backends |
|
|
240 | might be supported on the current system, you would need to look at |
|
|
241 | \&\f(CW\*(C`ev_embeddable_backends () & ev_supported_backends ()\*(C'\fR, likewise for |
|
|
242 | recommended ones. |
|
|
243 | .Sp |
|
|
244 | See the description of \f(CW\*(C`ev_embed\*(C'\fR watchers for more info. |
236 | .IP "ev_set_allocator (void *(*cb)(void *ptr, long size))" 4 |
245 | .IP "ev_set_allocator (void *(*cb)(void *ptr, long size))" 4 |
237 | .IX Item "ev_set_allocator (void *(*cb)(void *ptr, long size))" |
246 | .IX Item "ev_set_allocator (void *(*cb)(void *ptr, long size))" |
238 | Sets the allocation function to use (the prototype is similar to the |
247 | Sets the allocation function to use (the prototype is similar to the |
239 | realloc C function, the semantics are identical). It is used to allocate |
248 | realloc C function, the semantics are identical). It is used to allocate |
240 | and free memory (no surprises here). If it returns zero when memory |
249 | and free memory (no surprises here). If it returns zero when memory |
… | |
… | |
449 | \& fatal ("no epoll found here, maybe it hides under your chair"); |
458 | \& fatal ("no epoll found here, maybe it hides under your chair"); |
450 | .Ve |
459 | .Ve |
451 | .IP "ev_default_destroy ()" 4 |
460 | .IP "ev_default_destroy ()" 4 |
452 | .IX Item "ev_default_destroy ()" |
461 | .IX Item "ev_default_destroy ()" |
453 | Destroys the default loop again (frees all memory and kernel state |
462 | Destroys the default loop again (frees all memory and kernel state |
454 | etc.). This stops all registered event watchers (by not touching them in |
463 | etc.). None of the active event watchers will be stopped in the normal |
455 | any way whatsoever, although you cannot rely on this :). |
464 | sense, so e.g. \f(CW\*(C`ev_is_active\*(C'\fR might still return true. It is your |
|
|
465 | responsibility to either stop all watchers cleanly yoursef \fIbefore\fR |
|
|
466 | calling this function, or cope with the fact afterwards (which is usually |
|
|
467 | the easiest thing, youc na just ignore the watchers and/or \f(CW\*(C`free ()\*(C'\fR them |
|
|
468 | for example). |
456 | .IP "ev_loop_destroy (loop)" 4 |
469 | .IP "ev_loop_destroy (loop)" 4 |
457 | .IX Item "ev_loop_destroy (loop)" |
470 | .IX Item "ev_loop_destroy (loop)" |
458 | Like \f(CW\*(C`ev_default_destroy\*(C'\fR, but destroys an event loop created by an |
471 | Like \f(CW\*(C`ev_default_destroy\*(C'\fR, but destroys an event loop created by an |
459 | earlier call to \f(CW\*(C`ev_loop_new\*(C'\fR. |
472 | earlier call to \f(CW\*(C`ev_loop_new\*(C'\fR. |
460 | .IP "ev_default_fork ()" 4 |
473 | .IP "ev_default_fork ()" 4 |
… | |
… | |
636 | *)\*(C'\fR), and you can stop watching for events at any time by calling the |
649 | *)\*(C'\fR), and you can stop watching for events at any time by calling the |
637 | corresponding stop function (\f(CW\*(C`ev_<type>_stop (loop, watcher *)\*(C'\fR. |
650 | corresponding stop function (\f(CW\*(C`ev_<type>_stop (loop, watcher *)\*(C'\fR. |
638 | .PP |
651 | .PP |
639 | As long as your watcher is active (has been started but not stopped) you |
652 | As long as your watcher is active (has been started but not stopped) you |
640 | must not touch the values stored in it. Most specifically you must never |
653 | must not touch the values stored in it. Most specifically you must never |
641 | reinitialise it or call its set macro. |
654 | reinitialise it or call its \f(CW\*(C`set\*(C'\fR macro. |
642 | .PP |
|
|
643 | You can check whether an event is active by calling the \f(CW\*(C`ev_is_active |
|
|
644 | (watcher *)\*(C'\fR macro. To see whether an event is outstanding (but the |
|
|
645 | callback for it has not been called yet) you can use the \f(CW\*(C`ev_is_pending |
|
|
646 | (watcher *)\*(C'\fR macro. |
|
|
647 | .PP |
655 | .PP |
648 | Each and every callback receives the event loop pointer as first, the |
656 | Each and every callback receives the event loop pointer as first, the |
649 | registered watcher structure as second, and a bitset of received events as |
657 | registered watcher structure as second, and a bitset of received events as |
650 | third argument. |
658 | third argument. |
651 | .PP |
659 | .PP |
… | |
… | |
709 | Libev will usually signal a few \*(L"dummy\*(R" events together with an error, |
717 | Libev will usually signal a few \*(L"dummy\*(R" events together with an error, |
710 | for example it might indicate that a fd is readable or writable, and if |
718 | for example it might indicate that a fd is readable or writable, and if |
711 | your callbacks is well-written it can just attempt the operation and cope |
719 | your callbacks is well-written it can just attempt the operation and cope |
712 | with the error from \fIread()\fR or \fIwrite()\fR. This will not work in multithreaded |
720 | with the error from \fIread()\fR or \fIwrite()\fR. This will not work in multithreaded |
713 | programs, though, so beware. |
721 | programs, though, so beware. |
|
|
722 | .Sh "\s-1SUMMARY\s0 \s-1OF\s0 \s-1GENERIC\s0 \s-1WATCHER\s0 \s-1FUNCTIONS\s0" |
|
|
723 | .IX Subsection "SUMMARY OF GENERIC WATCHER FUNCTIONS" |
|
|
724 | In the following description, \f(CW\*(C`TYPE\*(C'\fR stands for the watcher type, |
|
|
725 | e.g. \f(CW\*(C`timer\*(C'\fR for \f(CW\*(C`ev_timer\*(C'\fR watchers and \f(CW\*(C`io\*(C'\fR for \f(CW\*(C`ev_io\*(C'\fR watchers. |
|
|
726 | .ie n .IP """ev_init"" (ev_TYPE *watcher, callback)" 4 |
|
|
727 | .el .IP "\f(CWev_init\fR (ev_TYPE *watcher, callback)" 4 |
|
|
728 | .IX Item "ev_init (ev_TYPE *watcher, callback)" |
|
|
729 | This macro initialises the generic portion of a watcher. The contents |
|
|
730 | of the watcher object can be arbitrary (so \f(CW\*(C`malloc\*(C'\fR will do). Only |
|
|
731 | the generic parts of the watcher are initialised, you \fIneed\fR to call |
|
|
732 | the type-specific \f(CW\*(C`ev_TYPE_set\*(C'\fR macro afterwards to initialise the |
|
|
733 | type-specific parts. For each type there is also a \f(CW\*(C`ev_TYPE_init\*(C'\fR macro |
|
|
734 | which rolls both calls into one. |
|
|
735 | .Sp |
|
|
736 | You can reinitialise a watcher at any time as long as it has been stopped |
|
|
737 | (or never started) and there are no pending events outstanding. |
|
|
738 | .Sp |
|
|
739 | The callbakc is always of type \f(CW\*(C`void (*)(ev_loop *loop, ev_TYPE *watcher, |
|
|
740 | int revents)\*(C'\fR. |
|
|
741 | .ie n .IP """ev_TYPE_set"" (ev_TYPE *, [args])" 4 |
|
|
742 | .el .IP "\f(CWev_TYPE_set\fR (ev_TYPE *, [args])" 4 |
|
|
743 | .IX Item "ev_TYPE_set (ev_TYPE *, [args])" |
|
|
744 | This macro initialises the type-specific parts of a watcher. You need to |
|
|
745 | call \f(CW\*(C`ev_init\*(C'\fR at least once before you call this macro, but you can |
|
|
746 | call \f(CW\*(C`ev_TYPE_set\*(C'\fR any number of times. You must not, however, call this |
|
|
747 | macro on a watcher that is active (it can be pending, however, which is a |
|
|
748 | difference to the \f(CW\*(C`ev_init\*(C'\fR macro). |
|
|
749 | .Sp |
|
|
750 | Although some watcher types do not have type-specific arguments |
|
|
751 | (e.g. \f(CW\*(C`ev_prepare\*(C'\fR) you still need to call its \f(CW\*(C`set\*(C'\fR macro. |
|
|
752 | .ie n .IP """ev_TYPE_init"" (ev_TYPE *watcher, callback, [args])" 4 |
|
|
753 | .el .IP "\f(CWev_TYPE_init\fR (ev_TYPE *watcher, callback, [args])" 4 |
|
|
754 | .IX Item "ev_TYPE_init (ev_TYPE *watcher, callback, [args])" |
|
|
755 | This convinience macro rolls both \f(CW\*(C`ev_init\*(C'\fR and \f(CW\*(C`ev_TYPE_set\*(C'\fR macro |
|
|
756 | calls into a single call. This is the most convinient method to initialise |
|
|
757 | a watcher. The same limitations apply, of course. |
|
|
758 | .ie n .IP """ev_TYPE_start"" (loop *, ev_TYPE *watcher)" 4 |
|
|
759 | .el .IP "\f(CWev_TYPE_start\fR (loop *, ev_TYPE *watcher)" 4 |
|
|
760 | .IX Item "ev_TYPE_start (loop *, ev_TYPE *watcher)" |
|
|
761 | Starts (activates) the given watcher. Only active watchers will receive |
|
|
762 | events. If the watcher is already active nothing will happen. |
|
|
763 | .ie n .IP """ev_TYPE_stop"" (loop *, ev_TYPE *watcher)" 4 |
|
|
764 | .el .IP "\f(CWev_TYPE_stop\fR (loop *, ev_TYPE *watcher)" 4 |
|
|
765 | .IX Item "ev_TYPE_stop (loop *, ev_TYPE *watcher)" |
|
|
766 | Stops the given watcher again (if active) and clears the pending |
|
|
767 | status. It is possible that stopped watchers are pending (for example, |
|
|
768 | non-repeating timers are being stopped when they become pending), but |
|
|
769 | \&\f(CW\*(C`ev_TYPE_stop\*(C'\fR ensures that the watcher is neither active nor pending. If |
|
|
770 | you want to free or reuse the memory used by the watcher it is therefore a |
|
|
771 | good idea to always call its \f(CW\*(C`ev_TYPE_stop\*(C'\fR function. |
|
|
772 | .IP "bool ev_is_active (ev_TYPE *watcher)" 4 |
|
|
773 | .IX Item "bool ev_is_active (ev_TYPE *watcher)" |
|
|
774 | Returns a true value iff the watcher is active (i.e. it has been started |
|
|
775 | and not yet been stopped). As long as a watcher is active you must not modify |
|
|
776 | it. |
|
|
777 | .IP "bool ev_is_pending (ev_TYPE *watcher)" 4 |
|
|
778 | .IX Item "bool ev_is_pending (ev_TYPE *watcher)" |
|
|
779 | Returns a true value iff the watcher is pending, (i.e. it has outstanding |
|
|
780 | events but its callback has not yet been invoked). As long as a watcher |
|
|
781 | is pending (but not active) you must not call an init function on it (but |
|
|
782 | \&\f(CW\*(C`ev_TYPE_set\*(C'\fR is safe) and you must make sure the watcher is available to |
|
|
783 | libev (e.g. you cnanot \f(CW\*(C`free ()\*(C'\fR it). |
|
|
784 | .IP "callback = ev_cb (ev_TYPE *watcher)" 4 |
|
|
785 | .IX Item "callback = ev_cb (ev_TYPE *watcher)" |
|
|
786 | Returns the callback currently set on the watcher. |
|
|
787 | .IP "ev_cb_set (ev_TYPE *watcher, callback)" 4 |
|
|
788 | .IX Item "ev_cb_set (ev_TYPE *watcher, callback)" |
|
|
789 | Change the callback. You can change the callback at virtually any time |
|
|
790 | (modulo threads). |
714 | .Sh "\s-1ASSOCIATING\s0 \s-1CUSTOM\s0 \s-1DATA\s0 \s-1WITH\s0 A \s-1WATCHER\s0" |
791 | .Sh "\s-1ASSOCIATING\s0 \s-1CUSTOM\s0 \s-1DATA\s0 \s-1WITH\s0 A \s-1WATCHER\s0" |
715 | .IX Subsection "ASSOCIATING CUSTOM DATA WITH A WATCHER" |
792 | .IX Subsection "ASSOCIATING CUSTOM DATA WITH A WATCHER" |
716 | Each watcher has, by default, a member \f(CW\*(C`void *data\*(C'\fR that you can change |
793 | Each watcher has, by default, a member \f(CW\*(C`void *data\*(C'\fR that you can change |
717 | and read at any time, libev will completely ignore it. This can be used |
794 | and read at any time, libev will completely ignore it. This can be used |
718 | to associate arbitrary data with your watcher. If you need more data and |
795 | to associate arbitrary data with your watcher. If you need more data and |
… | |
… | |
918 | (and unfortunately a bit complex). |
995 | (and unfortunately a bit complex). |
919 | .PP |
996 | .PP |
920 | Unlike \f(CW\*(C`ev_timer\*(C'\fR's, they are not based on real time (or relative time) |
997 | Unlike \f(CW\*(C`ev_timer\*(C'\fR's, they are not based on real time (or relative time) |
921 | but on wallclock time (absolute time). You can tell a periodic watcher |
998 | but on wallclock time (absolute time). You can tell a periodic watcher |
922 | to trigger \*(L"at\*(R" some specific point in time. For example, if you tell a |
999 | to trigger \*(L"at\*(R" some specific point in time. For example, if you tell a |
923 | periodic watcher to trigger in 10 seconds (by specifiying e.g. c<ev_now () |
1000 | periodic watcher to trigger in 10 seconds (by specifiying e.g. \f(CW\*(C`ev_now () |
924 | + 10.>) and then reset your system clock to the last year, then it will |
1001 | + 10.\*(C'\fR) and then reset your system clock to the last year, then it will |
925 | take a year to trigger the event (unlike an \f(CW\*(C`ev_timer\*(C'\fR, which would trigger |
1002 | take a year to trigger the event (unlike an \f(CW\*(C`ev_timer\*(C'\fR, which would trigger |
926 | roughly 10 seconds later and of course not if you reset your system time |
1003 | roughly 10 seconds later and of course not if you reset your system time |
927 | again). |
1004 | again). |
928 | .PP |
1005 | .PP |
929 | They can also be used to implement vastly more complex timers, such as |
1006 | They can also be used to implement vastly more complex timers, such as |
… | |
… | |
1159 | .IX Subsection "ev_prepare and ev_check - customise your event loop" |
1236 | .IX Subsection "ev_prepare and ev_check - customise your event loop" |
1160 | Prepare and check watchers are usually (but not always) used in tandem: |
1237 | Prepare and check watchers are usually (but not always) used in tandem: |
1161 | prepare watchers get invoked before the process blocks and check watchers |
1238 | prepare watchers get invoked before the process blocks and check watchers |
1162 | afterwards. |
1239 | afterwards. |
1163 | .PP |
1240 | .PP |
1164 | Their main purpose is to integrate other event mechanisms into libev. This |
1241 | Their main purpose is to integrate other event mechanisms into libev and |
1165 | could be used, for example, to track variable changes, implement your own |
1242 | their use is somewhat advanced. This could be used, for example, to track |
1166 | watchers, integrate net-snmp or a coroutine library and lots more. |
1243 | variable changes, implement your own watchers, integrate net-snmp or a |
|
|
1244 | coroutine library and lots more. |
1167 | .PP |
1245 | .PP |
1168 | This is done by examining in each prepare call which file descriptors need |
1246 | This is done by examining in each prepare call which file descriptors need |
1169 | to be watched by the other library, registering \f(CW\*(C`ev_io\*(C'\fR watchers for |
1247 | to be watched by the other library, registering \f(CW\*(C`ev_io\*(C'\fR watchers for |
1170 | them and starting an \f(CW\*(C`ev_timer\*(C'\fR watcher for any timeouts (many libraries |
1248 | them and starting an \f(CW\*(C`ev_timer\*(C'\fR watcher for any timeouts (many libraries |
1171 | provide just this functionality). Then, in the check watcher you check for |
1249 | provide just this functionality). Then, in the check watcher you check for |
… | |
… | |
1191 | Initialises and configures the prepare or check watcher \- they have no |
1269 | Initialises and configures the prepare or check watcher \- they have no |
1192 | parameters of any kind. There are \f(CW\*(C`ev_prepare_set\*(C'\fR and \f(CW\*(C`ev_check_set\*(C'\fR |
1270 | parameters of any kind. There are \f(CW\*(C`ev_prepare_set\*(C'\fR and \f(CW\*(C`ev_check_set\*(C'\fR |
1193 | macros, but using them is utterly, utterly and completely pointless. |
1271 | macros, but using them is utterly, utterly and completely pointless. |
1194 | .PP |
1272 | .PP |
1195 | Example: *TODO*. |
1273 | Example: *TODO*. |
|
|
1274 | .ie n .Sh """ev_embed"" \- when one backend isn't enough" |
|
|
1275 | .el .Sh "\f(CWev_embed\fP \- when one backend isn't enough" |
|
|
1276 | .IX Subsection "ev_embed - when one backend isn't enough" |
|
|
1277 | This is a rather advanced watcher type that lets you embed one event loop |
|
|
1278 | into another (currently only \f(CW\*(C`ev_io\*(C'\fR events are supported in the embedded |
|
|
1279 | loop, other types of watchers might be handled in a delayed or incorrect |
|
|
1280 | fashion and must not be used). |
|
|
1281 | .PP |
|
|
1282 | There are primarily two reasons you would want that: work around bugs and |
|
|
1283 | prioritise I/O. |
|
|
1284 | .PP |
|
|
1285 | As an example for a bug workaround, the kqueue backend might only support |
|
|
1286 | sockets on some platform, so it is unusable as generic backend, but you |
|
|
1287 | still want to make use of it because you have many sockets and it scales |
|
|
1288 | so nicely. In this case, you would create a kqueue-based loop and embed it |
|
|
1289 | into your default loop (which might use e.g. poll). Overall operation will |
|
|
1290 | be a bit slower because first libev has to poll and then call kevent, but |
|
|
1291 | at least you can use both at what they are best. |
|
|
1292 | .PP |
|
|
1293 | As for prioritising I/O: rarely you have the case where some fds have |
|
|
1294 | to be watched and handled very quickly (with low latency), and even |
|
|
1295 | priorities and idle watchers might have too much overhead. In this case |
|
|
1296 | you would put all the high priority stuff in one loop and all the rest in |
|
|
1297 | a second one, and embed the second one in the first. |
|
|
1298 | .PP |
|
|
1299 | As long as the watcher is active, the callback will be invoked every time |
|
|
1300 | there might be events pending in the embedded loop. The callback must then |
|
|
1301 | call \f(CW\*(C`ev_embed_sweep (mainloop, watcher)\*(C'\fR to make a single sweep and invoke |
|
|
1302 | their callbacks (you could also start an idle watcher to give the embedded |
|
|
1303 | loop strictly lower priority for example). You can also set the callback |
|
|
1304 | to \f(CW0\fR, in which case the embed watcher will automatically execute the |
|
|
1305 | embedded loop sweep. |
|
|
1306 | .PP |
|
|
1307 | As long as the watcher is started it will automatically handle events. The |
|
|
1308 | callback will be invoked whenever some events have been handled. You can |
|
|
1309 | set the callback to \f(CW0\fR to avoid having to specify one if you are not |
|
|
1310 | interested in that. |
|
|
1311 | .PP |
|
|
1312 | Also, there have not currently been made special provisions for forking: |
|
|
1313 | when you fork, you not only have to call \f(CW\*(C`ev_loop_fork\*(C'\fR on both loops, |
|
|
1314 | but you will also have to stop and restart any \f(CW\*(C`ev_embed\*(C'\fR watchers |
|
|
1315 | yourself. |
|
|
1316 | .PP |
|
|
1317 | Unfortunately, not all backends are embeddable, only the ones returned by |
|
|
1318 | \&\f(CW\*(C`ev_embeddable_backends\*(C'\fR are, which, unfortunately, does not include any |
|
|
1319 | portable one. |
|
|
1320 | .PP |
|
|
1321 | So when you want to use this feature you will always have to be prepared |
|
|
1322 | that you cannot get an embeddable loop. The recommended way to get around |
|
|
1323 | this is to have a separate variables for your embeddable loop, try to |
|
|
1324 | create it, and if that fails, use the normal loop for everything: |
|
|
1325 | .PP |
|
|
1326 | .Vb 3 |
|
|
1327 | \& struct ev_loop *loop_hi = ev_default_init (0); |
|
|
1328 | \& struct ev_loop *loop_lo = 0; |
|
|
1329 | \& struct ev_embed embed; |
|
|
1330 | .Ve |
|
|
1331 | .PP |
|
|
1332 | .Vb 5 |
|
|
1333 | \& // see if there is a chance of getting one that works |
|
|
1334 | \& // (remember that a flags value of 0 means autodetection) |
|
|
1335 | \& loop_lo = ev_embeddable_backends () & ev_recommended_backends () |
|
|
1336 | \& ? ev_loop_new (ev_embeddable_backends () & ev_recommended_backends ()) |
|
|
1337 | \& : 0; |
|
|
1338 | .Ve |
|
|
1339 | .PP |
|
|
1340 | .Vb 8 |
|
|
1341 | \& // if we got one, then embed it, otherwise default to loop_hi |
|
|
1342 | \& if (loop_lo) |
|
|
1343 | \& { |
|
|
1344 | \& ev_embed_init (&embed, 0, loop_lo); |
|
|
1345 | \& ev_embed_start (loop_hi, &embed); |
|
|
1346 | \& } |
|
|
1347 | \& else |
|
|
1348 | \& loop_lo = loop_hi; |
|
|
1349 | .Ve |
|
|
1350 | .IP "ev_embed_init (ev_embed *, callback, struct ev_loop *embedded_loop)" 4 |
|
|
1351 | .IX Item "ev_embed_init (ev_embed *, callback, struct ev_loop *embedded_loop)" |
|
|
1352 | .PD 0 |
|
|
1353 | .IP "ev_embed_set (ev_embed *, callback, struct ev_loop *embedded_loop)" 4 |
|
|
1354 | .IX Item "ev_embed_set (ev_embed *, callback, struct ev_loop *embedded_loop)" |
|
|
1355 | .PD |
|
|
1356 | Configures the watcher to embed the given loop, which must be |
|
|
1357 | embeddable. If the callback is \f(CW0\fR, then \f(CW\*(C`ev_embed_sweep\*(C'\fR will be |
|
|
1358 | invoked automatically, otherwise it is the responsibility of the callback |
|
|
1359 | to invoke it (it will continue to be called until the sweep has been done, |
|
|
1360 | if you do not want thta, you need to temporarily stop the embed watcher). |
|
|
1361 | .IP "ev_embed_sweep (loop, ev_embed *)" 4 |
|
|
1362 | .IX Item "ev_embed_sweep (loop, ev_embed *)" |
|
|
1363 | Make a single, non-blocking sweep over the embedded loop. This works |
|
|
1364 | similarly to \f(CW\*(C`ev_loop (embedded_loop, EVLOOP_NONBLOCK)\*(C'\fR, but in the most |
|
|
1365 | apropriate way for embedded loops. |
1196 | .SH "OTHER FUNCTIONS" |
1366 | .SH "OTHER FUNCTIONS" |
1197 | .IX Header "OTHER FUNCTIONS" |
1367 | .IX Header "OTHER FUNCTIONS" |
1198 | There are some other functions of possible interest. Described. Here. Now. |
1368 | There are some other functions of possible interest. Described. Here. Now. |
1199 | .IP "ev_once (loop, int fd, int events, ev_tstamp timeout, callback)" 4 |
1369 | .IP "ev_once (loop, int fd, int events, ev_tstamp timeout, callback)" 4 |
1200 | .IX Item "ev_once (loop, int fd, int events, ev_tstamp timeout, callback)" |
1370 | .IX Item "ev_once (loop, int fd, int events, ev_tstamp timeout, callback)" |
… | |
… | |
1229 | .Ve |
1399 | .Ve |
1230 | .Sp |
1400 | .Sp |
1231 | .Vb 1 |
1401 | .Vb 1 |
1232 | \& ev_once (STDIN_FILENO, EV_READ, 10., stdin_ready, 0); |
1402 | \& ev_once (STDIN_FILENO, EV_READ, 10., stdin_ready, 0); |
1233 | .Ve |
1403 | .Ve |
1234 | .IP "ev_feed_event (loop, watcher, int events)" 4 |
1404 | .IP "ev_feed_event (ev_loop *, watcher *, int revents)" 4 |
1235 | .IX Item "ev_feed_event (loop, watcher, int events)" |
1405 | .IX Item "ev_feed_event (ev_loop *, watcher *, int revents)" |
1236 | Feeds the given event set into the event loop, as if the specified event |
1406 | Feeds the given event set into the event loop, as if the specified event |
1237 | had happened for the specified watcher (which must be a pointer to an |
1407 | had happened for the specified watcher (which must be a pointer to an |
1238 | initialised but not necessarily started event watcher). |
1408 | initialised but not necessarily started event watcher). |
1239 | .IP "ev_feed_fd_event (loop, int fd, int revents)" 4 |
1409 | .IP "ev_feed_fd_event (ev_loop *, int fd, int revents)" 4 |
1240 | .IX Item "ev_feed_fd_event (loop, int fd, int revents)" |
1410 | .IX Item "ev_feed_fd_event (ev_loop *, int fd, int revents)" |
1241 | Feed an event on the given fd, as if a file descriptor backend detected |
1411 | Feed an event on the given fd, as if a file descriptor backend detected |
1242 | the given events it. |
1412 | the given events it. |
1243 | .IP "ev_feed_signal_event (loop, int signum)" 4 |
1413 | .IP "ev_feed_signal_event (ev_loop *loop, int signum)" 4 |
1244 | .IX Item "ev_feed_signal_event (loop, int signum)" |
1414 | .IX Item "ev_feed_signal_event (ev_loop *loop, int signum)" |
1245 | Feed an event as if the given signal occured (loop must be the default loop!). |
1415 | Feed an event as if the given signal occured (\f(CW\*(C`loop\*(C'\fR must be the default |
|
|
1416 | loop!). |
1246 | .SH "LIBEVENT EMULATION" |
1417 | .SH "LIBEVENT EMULATION" |
1247 | .IX Header "LIBEVENT EMULATION" |
1418 | .IX Header "LIBEVENT EMULATION" |
1248 | Libev offers a compatibility emulation layer for libevent. It cannot |
1419 | Libev offers a compatibility emulation layer for libevent. It cannot |
1249 | emulate the internals of libevent, so here are some usage hints: |
1420 | emulate the internals of libevent, so here are some usage hints: |
1250 | .IP "* Use it by including <event.h>, as usual." 4 |
1421 | .IP "* Use it by including <event.h>, as usual." 4 |
… | |
… | |
1261 | .IP "* The libev emulation is \fInot\fR \s-1ABI\s0 compatible to libevent, you need to use the libev header file and library." 4 |
1432 | .IP "* The libev emulation is \fInot\fR \s-1ABI\s0 compatible to libevent, you need to use the libev header file and library." 4 |
1262 | .IX Item "The libev emulation is not ABI compatible to libevent, you need to use the libev header file and library." |
1433 | .IX Item "The libev emulation is not ABI compatible to libevent, you need to use the libev header file and library." |
1263 | .PD |
1434 | .PD |
1264 | .SH "\*(C+ SUPPORT" |
1435 | .SH "\*(C+ SUPPORT" |
1265 | .IX Header " SUPPORT" |
1436 | .IX Header " SUPPORT" |
1266 | \&\s-1TBD\s0. |
1437 | Libev comes with some simplistic wrapper classes for \*(C+ that mainly allow |
|
|
1438 | you to use some convinience methods to start/stop watchers and also change |
|
|
1439 | the callback model to a model using method callbacks on objects. |
|
|
1440 | .PP |
|
|
1441 | To use it, |
|
|
1442 | .PP |
|
|
1443 | .Vb 1 |
|
|
1444 | \& #include <ev++.h> |
|
|
1445 | .Ve |
|
|
1446 | .PP |
|
|
1447 | (it is not installed by default). This automatically includes \fIev.h\fR |
|
|
1448 | and puts all of its definitions (many of them macros) into the global |
|
|
1449 | namespace. All \*(C+ specific things are put into the \f(CW\*(C`ev\*(C'\fR namespace. |
|
|
1450 | .PP |
|
|
1451 | It should support all the same embedding options as \fIev.h\fR, most notably |
|
|
1452 | \&\f(CW\*(C`EV_MULTIPLICITY\*(C'\fR. |
|
|
1453 | .PP |
|
|
1454 | Here is a list of things available in the \f(CW\*(C`ev\*(C'\fR namespace: |
|
|
1455 | .ie n .IP """ev::READ""\fR, \f(CW""ev::WRITE"" etc." 4 |
|
|
1456 | .el .IP "\f(CWev::READ\fR, \f(CWev::WRITE\fR etc." 4 |
|
|
1457 | .IX Item "ev::READ, ev::WRITE etc." |
|
|
1458 | These are just enum values with the same values as the \f(CW\*(C`EV_READ\*(C'\fR etc. |
|
|
1459 | macros from \fIev.h\fR. |
|
|
1460 | .ie n .IP """ev::tstamp""\fR, \f(CW""ev::now""" 4 |
|
|
1461 | .el .IP "\f(CWev::tstamp\fR, \f(CWev::now\fR" 4 |
|
|
1462 | .IX Item "ev::tstamp, ev::now" |
|
|
1463 | Aliases to the same types/functions as with the \f(CW\*(C`ev_\*(C'\fR prefix. |
|
|
1464 | .ie n .IP """ev::io""\fR, \f(CW""ev::timer""\fR, \f(CW""ev::periodic""\fR, \f(CW""ev::idle""\fR, \f(CW""ev::sig"" etc." 4 |
|
|
1465 | .el .IP "\f(CWev::io\fR, \f(CWev::timer\fR, \f(CWev::periodic\fR, \f(CWev::idle\fR, \f(CWev::sig\fR etc." 4 |
|
|
1466 | .IX Item "ev::io, ev::timer, ev::periodic, ev::idle, ev::sig etc." |
|
|
1467 | For each \f(CW\*(C`ev_TYPE\*(C'\fR watcher in \fIev.h\fR there is a corresponding class of |
|
|
1468 | the same name in the \f(CW\*(C`ev\*(C'\fR namespace, with the exception of \f(CW\*(C`ev_signal\*(C'\fR |
|
|
1469 | which is called \f(CW\*(C`ev::sig\*(C'\fR to avoid clashes with the \f(CW\*(C`signal\*(C'\fR macro |
|
|
1470 | defines by many implementations. |
|
|
1471 | .Sp |
|
|
1472 | All of those classes have these methods: |
|
|
1473 | .RS 4 |
|
|
1474 | .IP "ev::TYPE::TYPE (object *, object::method *)" 4 |
|
|
1475 | .IX Item "ev::TYPE::TYPE (object *, object::method *)" |
|
|
1476 | .PD 0 |
|
|
1477 | .IP "ev::TYPE::TYPE (object *, object::method *, struct ev_loop *)" 4 |
|
|
1478 | .IX Item "ev::TYPE::TYPE (object *, object::method *, struct ev_loop *)" |
|
|
1479 | .IP "ev::TYPE::~TYPE" 4 |
|
|
1480 | .IX Item "ev::TYPE::~TYPE" |
|
|
1481 | .PD |
|
|
1482 | The constructor takes a pointer to an object and a method pointer to |
|
|
1483 | the event handler callback to call in this class. The constructor calls |
|
|
1484 | \&\f(CW\*(C`ev_init\*(C'\fR for you, which means you have to call the \f(CW\*(C`set\*(C'\fR method |
|
|
1485 | before starting it. If you do not specify a loop then the constructor |
|
|
1486 | automatically associates the default loop with this watcher. |
|
|
1487 | .Sp |
|
|
1488 | The destructor automatically stops the watcher if it is active. |
|
|
1489 | .IP "w\->set (struct ev_loop *)" 4 |
|
|
1490 | .IX Item "w->set (struct ev_loop *)" |
|
|
1491 | Associates a different \f(CW\*(C`struct ev_loop\*(C'\fR with this watcher. You can only |
|
|
1492 | do this when the watcher is inactive (and not pending either). |
|
|
1493 | .IP "w\->set ([args])" 4 |
|
|
1494 | .IX Item "w->set ([args])" |
|
|
1495 | Basically the same as \f(CW\*(C`ev_TYPE_set\*(C'\fR, with the same args. Must be |
|
|
1496 | called at least once. Unlike the C counterpart, an active watcher gets |
|
|
1497 | automatically stopped and restarted. |
|
|
1498 | .IP "w\->start ()" 4 |
|
|
1499 | .IX Item "w->start ()" |
|
|
1500 | Starts the watcher. Note that there is no \f(CW\*(C`loop\*(C'\fR argument as the |
|
|
1501 | constructor already takes the loop. |
|
|
1502 | .IP "w\->stop ()" 4 |
|
|
1503 | .IX Item "w->stop ()" |
|
|
1504 | Stops the watcher if it is active. Again, no \f(CW\*(C`loop\*(C'\fR argument. |
|
|
1505 | .ie n .IP "w\->again () ""ev::timer""\fR, \f(CW""ev::periodic"" only" 4 |
|
|
1506 | .el .IP "w\->again () \f(CWev::timer\fR, \f(CWev::periodic\fR only" 4 |
|
|
1507 | .IX Item "w->again () ev::timer, ev::periodic only" |
|
|
1508 | For \f(CW\*(C`ev::timer\*(C'\fR and \f(CW\*(C`ev::periodic\*(C'\fR, this invokes the corresponding |
|
|
1509 | \&\f(CW\*(C`ev_TYPE_again\*(C'\fR function. |
|
|
1510 | .ie n .IP "w\->sweep () ""ev::embed"" only" 4 |
|
|
1511 | .el .IP "w\->sweep () \f(CWev::embed\fR only" 4 |
|
|
1512 | .IX Item "w->sweep () ev::embed only" |
|
|
1513 | Invokes \f(CW\*(C`ev_embed_sweep\*(C'\fR. |
|
|
1514 | .RE |
|
|
1515 | .RS 4 |
|
|
1516 | .RE |
|
|
1517 | .PP |
|
|
1518 | Example: Define a class with an \s-1IO\s0 and idle watcher, start one of them in |
|
|
1519 | the constructor. |
|
|
1520 | .PP |
|
|
1521 | .Vb 4 |
|
|
1522 | \& class myclass |
|
|
1523 | \& { |
|
|
1524 | \& ev_io io; void io_cb (ev::io &w, int revents); |
|
|
1525 | \& ev_idle idle void idle_cb (ev::idle &w, int revents); |
|
|
1526 | .Ve |
|
|
1527 | .PP |
|
|
1528 | .Vb 2 |
|
|
1529 | \& myclass (); |
|
|
1530 | \& } |
|
|
1531 | .Ve |
|
|
1532 | .PP |
|
|
1533 | .Vb 6 |
|
|
1534 | \& myclass::myclass (int fd) |
|
|
1535 | \& : io (this, &myclass::io_cb), |
|
|
1536 | \& idle (this, &myclass::idle_cb) |
|
|
1537 | \& { |
|
|
1538 | \& io.start (fd, ev::READ); |
|
|
1539 | \& } |
|
|
1540 | .Ve |
1267 | .SH "AUTHOR" |
1541 | .SH "AUTHOR" |
1268 | .IX Header "AUTHOR" |
1542 | .IX Header "AUTHOR" |
1269 | Marc Lehmann <libev@schmorp.de>. |
1543 | Marc Lehmann <libev@schmorp.de>. |