| … | |
… | |
| 8 | |
8 | |
| 9 | =head2 EXAMPLE PROGRAM |
9 | =head2 EXAMPLE PROGRAM |
| 10 | |
10 | |
| 11 | // a single header file is required |
11 | // a single header file is required |
| 12 | #include <ev.h> |
12 | #include <ev.h> |
|
|
13 | |
|
|
14 | #include <stdio.h> // for puts |
| 13 | |
15 | |
| 14 | // every watcher type has its own typedef'd struct |
16 | // every watcher type has its own typedef'd struct |
| 15 | // with the name ev_TYPE |
17 | // with the name ev_TYPE |
| 16 | ev_io stdin_watcher; |
18 | ev_io stdin_watcher; |
| 17 | ev_timer timeout_watcher; |
19 | ev_timer timeout_watcher; |
| … | |
… | |
| 418 | starting a watcher (without re-setting it) also usually doesn't cause |
420 | starting a watcher (without re-setting it) also usually doesn't cause |
| 419 | extra overhead. A fork can both result in spurious notifications as well |
421 | extra overhead. A fork can both result in spurious notifications as well |
| 420 | as in libev having to destroy and recreate the epoll object, which can |
422 | as in libev having to destroy and recreate the epoll object, which can |
| 421 | take considerable time and thus should be avoided. |
423 | take considerable time and thus should be avoided. |
| 422 | |
424 | |
| 423 | All this means that, in practise, C<EVBACKEND_SELECT> can be as fast or |
425 | All this means that, in practice, C<EVBACKEND_SELECT> can be as fast or |
| 424 | faster then epoll for maybe up to a hundred file descriptors, depending on |
426 | faster than epoll for maybe up to a hundred file descriptors, depending on |
| 425 | the usage. So sad. |
427 | the usage. So sad. |
| 426 | |
428 | |
| 427 | While nominally embeddable in other event loops, this feature is broken in |
429 | While nominally embeddable in other event loops, this feature is broken in |
| 428 | all kernel versions tested so far. |
430 | all kernel versions tested so far. |
| 429 | |
431 | |
| … | |
… | |
| 1419 | else |
1421 | else |
| 1420 | { |
1422 | { |
| 1421 | // callback was invoked, but there was some activity, re-arm |
1423 | // callback was invoked, but there was some activity, re-arm |
| 1422 | // the watcher to fire in last_activity + 60, which is |
1424 | // the watcher to fire in last_activity + 60, which is |
| 1423 | // guaranteed to be in the future, so "again" is positive: |
1425 | // guaranteed to be in the future, so "again" is positive: |
| 1424 | w->again = timeout - now; |
1426 | w->repeat = timeout - now; |
| 1425 | ev_timer_again (EV_A_ w); |
1427 | ev_timer_again (EV_A_ w); |
| 1426 | } |
1428 | } |
| 1427 | } |
1429 | } |
| 1428 | |
1430 | |
| 1429 | To summarise the callback: first calculate the real timeout (defined |
1431 | To summarise the callback: first calculate the real timeout (defined |
