| … | |
… | |
| 856 | (and unfortunately a bit complex). |
856 | (and unfortunately a bit complex). |
| 857 | |
857 | |
| 858 | Unlike C<ev_timer>'s, they are not based on real time (or relative time) |
858 | Unlike C<ev_timer>'s, they are not based on real time (or relative time) |
| 859 | but on wallclock time (absolute time). You can tell a periodic watcher |
859 | but on wallclock time (absolute time). You can tell a periodic watcher |
| 860 | to trigger "at" some specific point in time. For example, if you tell a |
860 | to trigger "at" some specific point in time. For example, if you tell a |
| 861 | periodic watcher to trigger in 10 seconds (by specifiying e.g. c<ev_now () |
861 | periodic watcher to trigger in 10 seconds (by specifiying e.g. C<ev_now () |
| 862 | + 10.>) and then reset your system clock to the last year, then it will |
862 | + 10.>) and then reset your system clock to the last year, then it will |
| 863 | take a year to trigger the event (unlike an C<ev_timer>, which would trigger |
863 | take a year to trigger the event (unlike an C<ev_timer>, which would trigger |
| 864 | roughly 10 seconds later and of course not if you reset your system time |
864 | roughly 10 seconds later and of course not if you reset your system time |
| 865 | again). |
865 | again). |
| 866 | |
866 | |
| … | |
… | |
| 1310 | |
1310 | |
| 1311 | =back |
1311 | =back |
| 1312 | |
1312 | |
| 1313 | =head1 C++ SUPPORT |
1313 | =head1 C++ SUPPORT |
| 1314 | |
1314 | |
| 1315 | TBD. |
1315 | Libev comes with some simplistic wrapper classes for C++ that mainly allow |
|
|
1316 | you to use some convinience methods to start/stop watchers and also change |
|
|
1317 | the callback model to a model using method callbacks on objects. |
|
|
1318 | |
|
|
1319 | To use it, |
|
|
1320 | |
|
|
1321 | #include <ev++.h> |
|
|
1322 | |
|
|
1323 | (it is not installed by default). This automatically includes F<ev.h> |
|
|
1324 | and puts all of its definitions (many of them macros) into the global |
|
|
1325 | namespace. All C++ specific things are put into the C<ev> namespace. |
|
|
1326 | |
|
|
1327 | It should support all the same embedding options as F<ev.h>, most notably |
|
|
1328 | C<EV_MULTIPLICITY>. |
|
|
1329 | |
|
|
1330 | Here is a list of things available in the C<ev> namespace: |
|
|
1331 | |
|
|
1332 | =over 4 |
|
|
1333 | |
|
|
1334 | =item C<ev::READ>, C<ev::WRITE> etc. |
|
|
1335 | |
|
|
1336 | These are just enum values with the same values as the C<EV_READ> etc. |
|
|
1337 | macros from F<ev.h>. |
|
|
1338 | |
|
|
1339 | =item C<ev::tstamp>, C<ev::now> |
|
|
1340 | |
|
|
1341 | Aliases to the same types/functions as with the C<ev_> prefix. |
|
|
1342 | |
|
|
1343 | =item C<ev::io>, C<ev::timer>, C<ev::periodic>, C<ev::idle>, C<ev::sig> etc. |
|
|
1344 | |
|
|
1345 | For each C<ev_TYPE> watcher in F<ev.h> there is a corresponding class of |
|
|
1346 | the same name in the C<ev> namespace, with the exception of C<ev_signal> |
|
|
1347 | which is called C<ev::sig> to avoid clashes with the C<signal> macro |
|
|
1348 | defines by many implementations. |
|
|
1349 | |
|
|
1350 | All of those classes have these methods: |
|
|
1351 | |
|
|
1352 | =over 4 |
|
|
1353 | |
|
|
1354 | =item ev::TYPE::TYPE (object *, object::method *) |
|
|
1355 | |
|
|
1356 | =item ev::TYPE::TYPE (object *, object::method *, struct ev_loop *) |
|
|
1357 | |
|
|
1358 | =item ev::TYPE::~TYPE |
|
|
1359 | |
|
|
1360 | The constructor takes a pointer to an object and a method pointer to |
|
|
1361 | the event handler callback to call in this class. The constructor calls |
|
|
1362 | C<ev_init> for you, which means you have to call the C<set> method |
|
|
1363 | before starting it. If you do not specify a loop then the constructor |
|
|
1364 | automatically associates the default loop with this watcher. |
|
|
1365 | |
|
|
1366 | The destructor automatically stops the watcher if it is active. |
|
|
1367 | |
|
|
1368 | =item w->set (struct ev_loop *) |
|
|
1369 | |
|
|
1370 | Associates a different C<struct ev_loop> with this watcher. You can only |
|
|
1371 | do this when the watcher is inactive (and not pending either). |
|
|
1372 | |
|
|
1373 | =item w->set ([args]) |
|
|
1374 | |
|
|
1375 | Basically the same as C<ev_TYPE_set>, with the same args. Must be |
|
|
1376 | called at least once. Unlike the C counterpart, an active watcher gets |
|
|
1377 | automatically stopped and restarted. |
|
|
1378 | |
|
|
1379 | =item w->start () |
|
|
1380 | |
|
|
1381 | Starts the watcher. Note that there is no C<loop> argument as the |
|
|
1382 | constructor already takes the loop. |
|
|
1383 | |
|
|
1384 | =item w->stop () |
|
|
1385 | |
|
|
1386 | Stops the watcher if it is active. Again, no C<loop> argument. |
|
|
1387 | |
|
|
1388 | =item w->again () C<ev::timer>, C<ev::periodic> only |
|
|
1389 | |
|
|
1390 | For C<ev::timer> and C<ev::periodic>, this invokes the corresponding |
|
|
1391 | C<ev_TYPE_again> function. |
|
|
1392 | |
|
|
1393 | =item w->sweep () C<ev::embed> only |
|
|
1394 | |
|
|
1395 | Invokes C<ev_embed_sweep>. |
|
|
1396 | |
|
|
1397 | =back |
|
|
1398 | |
|
|
1399 | =back |
|
|
1400 | |
|
|
1401 | Example: Define a class with an IO and idle watcher, start one of them in |
|
|
1402 | the constructor. |
|
|
1403 | |
|
|
1404 | class myclass |
|
|
1405 | { |
|
|
1406 | ev_io io; void io_cb (ev::io &w, int revents); |
|
|
1407 | ev_idle idle void idle_cb (ev::idle &w, int revents); |
|
|
1408 | |
|
|
1409 | myclass (); |
|
|
1410 | } |
|
|
1411 | |
|
|
1412 | myclass::myclass (int fd) |
|
|
1413 | : io (this, &myclass::io_cb), |
|
|
1414 | idle (this, &myclass::idle_cb) |
|
|
1415 | { |
|
|
1416 | io.start (fd, ev::READ); |
|
|
1417 | } |
| 1316 | |
1418 | |
| 1317 | =head1 AUTHOR |
1419 | =head1 AUTHOR |
| 1318 | |
1420 | |
| 1319 | Marc Lehmann <libev@schmorp.de>. |
1421 | Marc Lehmann <libev@schmorp.de>. |
| 1320 | |
1422 | |
