… | |
… | |
118 | Libev is very configurable. In this manual the default (and most common) |
118 | Libev is very configurable. In this manual the default (and most common) |
119 | configuration will be described, which supports multiple event loops. For |
119 | configuration will be described, which supports multiple event loops. For |
120 | more info about various configuration options please have a look at |
120 | more info about various configuration options please have a look at |
121 | B<EMBED> section in this manual. If libev was configured without support |
121 | B<EMBED> section in this manual. If libev was configured without support |
122 | for multiple event loops, then all functions taking an initial argument of |
122 | for multiple event loops, then all functions taking an initial argument of |
123 | name C<loop> (which is always of type C<ev_loop *>) will not have |
123 | name C<loop> (which is always of type C<struct ev_loop *>) will not have |
124 | this argument. |
124 | this argument. |
125 | |
125 | |
126 | =head2 TIME REPRESENTATION |
126 | =head2 TIME REPRESENTATION |
127 | |
127 | |
128 | Libev represents time as a single floating point number, representing |
128 | Libev represents time as a single floating point number, representing |
… | |
… | |
919 | |
919 | |
920 | While event loop modifications are allowed between invocations of |
920 | While event loop modifications are allowed between invocations of |
921 | C<release> and C<acquire> (that's their only purpose after all), no |
921 | C<release> and C<acquire> (that's their only purpose after all), no |
922 | modifications done will affect the event loop, i.e. adding watchers will |
922 | modifications done will affect the event loop, i.e. adding watchers will |
923 | have no effect on the set of file descriptors being watched, or the time |
923 | have no effect on the set of file descriptors being watched, or the time |
924 | waited. USe an C<ev_async> watcher to wake up C<ev_loop> when you want it |
924 | waited. Use an C<ev_async> watcher to wake up C<ev_loop> when you want it |
925 | to take note of any changes you made. |
925 | to take note of any changes you made. |
926 | |
926 | |
927 | In theory, threads executing C<ev_loop> will be async-cancel safe between |
927 | In theory, threads executing C<ev_loop> will be async-cancel safe between |
928 | invocations of C<release> and C<acquire>. |
928 | invocations of C<release> and C<acquire>. |
929 | |
929 | |
… | |
… | |
1126 | |
1126 | |
1127 | ev_io w; |
1127 | ev_io w; |
1128 | ev_init (&w, my_cb); |
1128 | ev_init (&w, my_cb); |
1129 | ev_io_set (&w, STDIN_FILENO, EV_READ); |
1129 | ev_io_set (&w, STDIN_FILENO, EV_READ); |
1130 | |
1130 | |
1131 | =item C<ev_TYPE_set> (ev_TYPE *, [args]) |
1131 | =item C<ev_TYPE_set> (ev_TYPE *watcher, [args]) |
1132 | |
1132 | |
1133 | This macro initialises the type-specific parts of a watcher. You need to |
1133 | This macro initialises the type-specific parts of a watcher. You need to |
1134 | call C<ev_init> at least once before you call this macro, but you can |
1134 | call C<ev_init> at least once before you call this macro, but you can |
1135 | call C<ev_TYPE_set> any number of times. You must not, however, call this |
1135 | call C<ev_TYPE_set> any number of times. You must not, however, call this |
1136 | macro on a watcher that is active (it can be pending, however, which is a |
1136 | macro on a watcher that is active (it can be pending, however, which is a |
… | |
… | |
1149 | |
1149 | |
1150 | Example: Initialise and set an C<ev_io> watcher in one step. |
1150 | Example: Initialise and set an C<ev_io> watcher in one step. |
1151 | |
1151 | |
1152 | ev_io_init (&w, my_cb, STDIN_FILENO, EV_READ); |
1152 | ev_io_init (&w, my_cb, STDIN_FILENO, EV_READ); |
1153 | |
1153 | |
1154 | =item C<ev_TYPE_start> (loop *, ev_TYPE *watcher) |
1154 | =item C<ev_TYPE_start> (loop, ev_TYPE *watcher) |
1155 | |
1155 | |
1156 | Starts (activates) the given watcher. Only active watchers will receive |
1156 | Starts (activates) the given watcher. Only active watchers will receive |
1157 | events. If the watcher is already active nothing will happen. |
1157 | events. If the watcher is already active nothing will happen. |
1158 | |
1158 | |
1159 | Example: Start the C<ev_io> watcher that is being abused as example in this |
1159 | Example: Start the C<ev_io> watcher that is being abused as example in this |
1160 | whole section. |
1160 | whole section. |
1161 | |
1161 | |
1162 | ev_io_start (EV_DEFAULT_UC, &w); |
1162 | ev_io_start (EV_DEFAULT_UC, &w); |
1163 | |
1163 | |
1164 | =item C<ev_TYPE_stop> (loop *, ev_TYPE *watcher) |
1164 | =item C<ev_TYPE_stop> (loop, ev_TYPE *watcher) |
1165 | |
1165 | |
1166 | Stops the given watcher if active, and clears the pending status (whether |
1166 | Stops the given watcher if active, and clears the pending status (whether |
1167 | the watcher was active or not). |
1167 | the watcher was active or not). |
1168 | |
1168 | |
1169 | It is possible that stopped watchers are pending - for example, |
1169 | It is possible that stopped watchers are pending - for example, |
… | |
… | |
1194 | =item ev_cb_set (ev_TYPE *watcher, callback) |
1194 | =item ev_cb_set (ev_TYPE *watcher, callback) |
1195 | |
1195 | |
1196 | Change the callback. You can change the callback at virtually any time |
1196 | Change the callback. You can change the callback at virtually any time |
1197 | (modulo threads). |
1197 | (modulo threads). |
1198 | |
1198 | |
1199 | =item ev_set_priority (ev_TYPE *watcher, priority) |
1199 | =item ev_set_priority (ev_TYPE *watcher, int priority) |
1200 | |
1200 | |
1201 | =item int ev_priority (ev_TYPE *watcher) |
1201 | =item int ev_priority (ev_TYPE *watcher) |
1202 | |
1202 | |
1203 | Set and query the priority of the watcher. The priority is a small |
1203 | Set and query the priority of the watcher. The priority is a small |
1204 | integer between C<EV_MAXPRI> (default: C<2>) and C<EV_MINPRI> |
1204 | integer between C<EV_MAXPRI> (default: C<2>) and C<EV_MINPRI> |
… | |
… | |
1235 | returns its C<revents> bitset (as if its callback was invoked). If the |
1235 | returns its C<revents> bitset (as if its callback was invoked). If the |
1236 | watcher isn't pending it does nothing and returns C<0>. |
1236 | watcher isn't pending it does nothing and returns C<0>. |
1237 | |
1237 | |
1238 | Sometimes it can be useful to "poll" a watcher instead of waiting for its |
1238 | Sometimes it can be useful to "poll" a watcher instead of waiting for its |
1239 | callback to be invoked, which can be accomplished with this function. |
1239 | callback to be invoked, which can be accomplished with this function. |
|
|
1240 | |
|
|
1241 | =item ev_feed_event (loop, ev_TYPE *watcher, int revents) |
|
|
1242 | |
|
|
1243 | Feeds the given event set into the event loop, as if the specified event |
|
|
1244 | had happened for the specified watcher (which must be a pointer to an |
|
|
1245 | initialised but not necessarily started event watcher). Obviously you must |
|
|
1246 | not free the watcher as long as it has pending events. |
|
|
1247 | |
|
|
1248 | Stopping the watcher, letting libev invoke it, or calling |
|
|
1249 | C<ev_clear_pending> will clear the pending event, even if the watcher was |
|
|
1250 | not started in the first place. |
|
|
1251 | |
|
|
1252 | See also C<ev_feed_fd_event> and C<ev_feed_signal_event> for related |
|
|
1253 | functions that do not need a watcher. |
1240 | |
1254 | |
1241 | =back |
1255 | =back |
1242 | |
1256 | |
1243 | |
1257 | |
1244 | =head2 ASSOCIATING CUSTOM DATA WITH A WATCHER |
1258 | =head2 ASSOCIATING CUSTOM DATA WITH A WATCHER |
… | |
… | |
1840 | C<repeat> value), or reset the running timer to the C<repeat> value. |
1854 | C<repeat> value), or reset the running timer to the C<repeat> value. |
1841 | |
1855 | |
1842 | This sounds a bit complicated, see L<Be smart about timeouts>, above, for a |
1856 | This sounds a bit complicated, see L<Be smart about timeouts>, above, for a |
1843 | usage example. |
1857 | usage example. |
1844 | |
1858 | |
1845 | =item ev_timer_remaining (loop, ev_timer *) |
1859 | =item ev_tstamp ev_timer_remaining (loop, ev_timer *) |
1846 | |
1860 | |
1847 | Returns the remaining time until a timer fires. If the timer is active, |
1861 | Returns the remaining time until a timer fires. If the timer is active, |
1848 | then this time is relative to the current event loop time, otherwise it's |
1862 | then this time is relative to the current event loop time, otherwise it's |
1849 | the timeout value currently configured. |
1863 | the timeout value currently configured. |
1850 | |
1864 | |
… | |
… | |
2967 | =head3 Queueing |
2981 | =head3 Queueing |
2968 | |
2982 | |
2969 | C<ev_async> does not support queueing of data in any way. The reason |
2983 | C<ev_async> does not support queueing of data in any way. The reason |
2970 | is that the author does not know of a simple (or any) algorithm for a |
2984 | is that the author does not know of a simple (or any) algorithm for a |
2971 | multiple-writer-single-reader queue that works in all cases and doesn't |
2985 | multiple-writer-single-reader queue that works in all cases and doesn't |
2972 | need elaborate support such as pthreads. |
2986 | need elaborate support such as pthreads or unportable memory access |
|
|
2987 | semantics. |
2973 | |
2988 | |
2974 | That means that if you want to queue data, you have to provide your own |
2989 | That means that if you want to queue data, you have to provide your own |
2975 | queue. But at least I can tell you how to implement locking around your |
2990 | queue. But at least I can tell you how to implement locking around your |
2976 | queue: |
2991 | queue: |
2977 | |
2992 | |
… | |
… | |
3135 | /* doh, nothing entered */; |
3150 | /* doh, nothing entered */; |
3136 | } |
3151 | } |
3137 | |
3152 | |
3138 | ev_once (STDIN_FILENO, EV_READ, 10., stdin_ready, 0); |
3153 | ev_once (STDIN_FILENO, EV_READ, 10., stdin_ready, 0); |
3139 | |
3154 | |
3140 | =item ev_feed_event (struct ev_loop *, watcher *, int revents) |
|
|
3141 | |
|
|
3142 | Feeds the given event set into the event loop, as if the specified event |
|
|
3143 | had happened for the specified watcher (which must be a pointer to an |
|
|
3144 | initialised but not necessarily started event watcher). |
|
|
3145 | |
|
|
3146 | =item ev_feed_fd_event (struct ev_loop *, int fd, int revents) |
3155 | =item ev_feed_fd_event (loop, int fd, int revents) |
3147 | |
3156 | |
3148 | Feed an event on the given fd, as if a file descriptor backend detected |
3157 | Feed an event on the given fd, as if a file descriptor backend detected |
3149 | the given events it. |
3158 | the given events it. |
3150 | |
3159 | |
3151 | =item ev_feed_signal_event (struct ev_loop *loop, int signum) |
3160 | =item ev_feed_signal_event (loop, int signum) |
3152 | |
3161 | |
3153 | Feed an event as if the given signal occurred (C<loop> must be the default |
3162 | Feed an event as if the given signal occurred (C<loop> must be the default |
3154 | loop!). |
3163 | loop!). |
3155 | |
3164 | |
3156 | =back |
3165 | =back |
… | |
… | |
3236 | |
3245 | |
3237 | =over 4 |
3246 | =over 4 |
3238 | |
3247 | |
3239 | =item ev::TYPE::TYPE () |
3248 | =item ev::TYPE::TYPE () |
3240 | |
3249 | |
3241 | =item ev::TYPE::TYPE (struct ev_loop *) |
3250 | =item ev::TYPE::TYPE (loop) |
3242 | |
3251 | |
3243 | =item ev::TYPE::~TYPE |
3252 | =item ev::TYPE::~TYPE |
3244 | |
3253 | |
3245 | The constructor (optionally) takes an event loop to associate the watcher |
3254 | The constructor (optionally) takes an event loop to associate the watcher |
3246 | with. If it is omitted, it will use C<EV_DEFAULT>. |
3255 | with. If it is omitted, it will use C<EV_DEFAULT>. |
… | |
… | |
3323 | Example: Use a plain function as callback. |
3332 | Example: Use a plain function as callback. |
3324 | |
3333 | |
3325 | static void io_cb (ev::io &w, int revents) { } |
3334 | static void io_cb (ev::io &w, int revents) { } |
3326 | iow.set <io_cb> (); |
3335 | iow.set <io_cb> (); |
3327 | |
3336 | |
3328 | =item w->set (struct ev_loop *) |
3337 | =item w->set (loop) |
3329 | |
3338 | |
3330 | Associates a different C<struct ev_loop> with this watcher. You can only |
3339 | Associates a different C<struct ev_loop> with this watcher. You can only |
3331 | do this when the watcher is inactive (and not pending either). |
3340 | do this when the watcher is inactive (and not pending either). |
3332 | |
3341 | |
3333 | =item w->set ([arguments]) |
3342 | =item w->set ([arguments]) |