… | |
… | |
275 | flags. If that is troubling you, check C<ev_backend ()> afterwards). |
275 | flags. If that is troubling you, check C<ev_backend ()> afterwards). |
276 | |
276 | |
277 | If you don't know what event loop to use, use the one returned from this |
277 | If you don't know what event loop to use, use the one returned from this |
278 | function. |
278 | function. |
279 | |
279 | |
|
|
280 | Note that this function is I<not> thread-safe, so if you want to use it |
|
|
281 | from multiple threads, you have to lock (note also that this is unlikely, |
|
|
282 | as loops cannot bes hared easily between threads anyway). |
|
|
283 | |
280 | The default loop is the only loop that can handle C<ev_signal> and |
284 | The default loop is the only loop that can handle C<ev_signal> and |
281 | C<ev_child> watchers, and to do this, it always registers a handler |
285 | C<ev_child> watchers, and to do this, it always registers a handler |
282 | for C<SIGCHLD>. If this is a problem for your app you can either |
286 | for C<SIGCHLD>. If this is a problem for your app you can either |
283 | create a dynamic loop with C<ev_loop_new> that doesn't do that, or you |
287 | create a dynamic loop with C<ev_loop_new> that doesn't do that, or you |
284 | can simply overwrite the C<SIGCHLD> signal handler I<after> calling |
288 | can simply overwrite the C<SIGCHLD> signal handler I<after> calling |
… | |
… | |
465 | |
469 | |
466 | Similar to C<ev_default_loop>, but always creates a new event loop that is |
470 | Similar to C<ev_default_loop>, but always creates a new event loop that is |
467 | always distinct from the default loop. Unlike the default loop, it cannot |
471 | always distinct from the default loop. Unlike the default loop, it cannot |
468 | handle signal and child watchers, and attempts to do so will be greeted by |
472 | handle signal and child watchers, and attempts to do so will be greeted by |
469 | undefined behaviour (or a failed assertion if assertions are enabled). |
473 | undefined behaviour (or a failed assertion if assertions are enabled). |
|
|
474 | |
|
|
475 | Note that this function I<is> thread-safe, and the recommended way to use |
|
|
476 | libev with threads is indeed to create one loop per thread, and using the |
|
|
477 | default loop in the "main" or "initial" thread. |
470 | |
478 | |
471 | Example: Try to create a event loop that uses epoll and nothing else. |
479 | Example: Try to create a event loop that uses epoll and nothing else. |
472 | |
480 | |
473 | struct ev_loop *epoller = ev_loop_new (EVBACKEND_EPOLL | EVFLAG_NOENV); |
481 | struct ev_loop *epoller = ev_loop_new (EVBACKEND_EPOLL | EVFLAG_NOENV); |
474 | if (!epoller) |
482 | if (!epoller) |
… | |
… | |
1085 | To support fork in your programs, you either have to call |
1093 | To support fork in your programs, you either have to call |
1086 | C<ev_default_fork ()> or C<ev_loop_fork ()> after a fork in the child, |
1094 | C<ev_default_fork ()> or C<ev_loop_fork ()> after a fork in the child, |
1087 | enable C<EVFLAG_FORKCHECK>, or resort to C<EVBACKEND_SELECT> or |
1095 | enable C<EVFLAG_FORKCHECK>, or resort to C<EVBACKEND_SELECT> or |
1088 | C<EVBACKEND_POLL>. |
1096 | C<EVBACKEND_POLL>. |
1089 | |
1097 | |
|
|
1098 | =head3 The special problem of SIGPIPE |
|
|
1099 | |
|
|
1100 | While not really specific to libev, it is easy to forget about SIGPIPE: |
|
|
1101 | when reading from a pipe whose other end has been closed, your program |
|
|
1102 | gets send a SIGPIPE, which, by default, aborts your program. For most |
|
|
1103 | programs this is sensible behaviour, for daemons, this is usually |
|
|
1104 | undesirable. |
|
|
1105 | |
|
|
1106 | So when you encounter spurious, unexplained daemon exits, make sure you |
|
|
1107 | ignore SIGPIPE (and maybe make sure you log the exit status of your daemon |
|
|
1108 | somewhere, as that would have given you a big clue). |
|
|
1109 | |
1090 | |
1110 | |
1091 | =head3 Watcher-Specific Functions |
1111 | =head3 Watcher-Specific Functions |
1092 | |
1112 | |
1093 | =over 4 |
1113 | =over 4 |
1094 | |
1114 | |
… | |
… | |
2268 | |
2288 | |
2269 | This call incurs the overhead of a syscall only once per loop iteration, |
2289 | This call incurs the overhead of a syscall only once per loop iteration, |
2270 | so while the overhead might be noticable, it doesn't apply to repeated |
2290 | so while the overhead might be noticable, it doesn't apply to repeated |
2271 | calls to C<ev_async_send>. |
2291 | calls to C<ev_async_send>. |
2272 | |
2292 | |
|
|
2293 | =item bool = ev_async_pending (ev_async *) |
|
|
2294 | |
|
|
2295 | Returns a non-zero value when C<ev_async_send> has been called on the |
|
|
2296 | watcher but the event has not yet been processed (or even noted) by the |
|
|
2297 | event loop. |
|
|
2298 | |
|
|
2299 | C<ev_async_send> sets a flag in the watcher and wakes up the loop. When |
|
|
2300 | the loop iterates next and checks for the watcher to have become active, |
|
|
2301 | it will reset the flag again. C<ev_async_pending> can be used to very |
|
|
2302 | quickly check wether invoking the loop might be a good idea. |
|
|
2303 | |
|
|
2304 | Not that this does I<not> check wether the watcher itself is pending, only |
|
|
2305 | wether it has been requested to make this watcher pending. |
|
|
2306 | |
2273 | =back |
2307 | =back |
2274 | |
2308 | |
2275 | |
2309 | |
2276 | =head1 OTHER FUNCTIONS |
2310 | =head1 OTHER FUNCTIONS |
2277 | |
2311 | |