… | |
… | |
117 | |
117 | |
118 | =item int ev_version_major () |
118 | =item int ev_version_major () |
119 | |
119 | |
120 | =item int ev_version_minor () |
120 | =item int ev_version_minor () |
121 | |
121 | |
122 | You can find out the major and minor version numbers of the library |
122 | You can find out the major and minor ABI version numbers of the library |
123 | you linked against by calling the functions C<ev_version_major> and |
123 | you linked against by calling the functions C<ev_version_major> and |
124 | C<ev_version_minor>. If you want, you can compare against the global |
124 | C<ev_version_minor>. If you want, you can compare against the global |
125 | symbols C<EV_VERSION_MAJOR> and C<EV_VERSION_MINOR>, which specify the |
125 | symbols C<EV_VERSION_MAJOR> and C<EV_VERSION_MINOR>, which specify the |
126 | version of the library your program was compiled against. |
126 | version of the library your program was compiled against. |
127 | |
127 | |
|
|
128 | These version numbers refer to the ABI version of the library, not the |
|
|
129 | release version. |
|
|
130 | |
128 | Usually, it's a good idea to terminate if the major versions mismatch, |
131 | Usually, it's a good idea to terminate if the major versions mismatch, |
129 | as this indicates an incompatible change. Minor versions are usually |
132 | as this indicates an incompatible change. Minor versions are usually |
130 | compatible to older versions, so a larger minor version alone is usually |
133 | compatible to older versions, so a larger minor version alone is usually |
131 | not a problem. |
134 | not a problem. |
132 | |
135 | |
133 | Example: Make sure we haven't accidentally been linked against the wrong |
136 | Example: Make sure we haven't accidentally been linked against the wrong |
134 | version. |
137 | version. |
… | |
… | |
486 | libev watchers. However, a pair of C<ev_prepare>/C<ev_check> watchers is |
489 | libev watchers. However, a pair of C<ev_prepare>/C<ev_check> watchers is |
487 | usually a better approach for this kind of thing. |
490 | usually a better approach for this kind of thing. |
488 | |
491 | |
489 | Here are the gory details of what C<ev_loop> does: |
492 | Here are the gory details of what C<ev_loop> does: |
490 | |
493 | |
|
|
494 | - Before the first iteration, call any pending watchers. |
491 | * If there are no active watchers (reference count is zero), return. |
495 | * If there are no active watchers (reference count is zero), return. |
492 | - Queue prepare watchers and then call all outstanding watchers. |
496 | - Queue all prepare watchers and then call all outstanding watchers. |
493 | - If we have been forked, recreate the kernel state. |
497 | - If we have been forked, recreate the kernel state. |
494 | - Update the kernel state with all outstanding changes. |
498 | - Update the kernel state with all outstanding changes. |
495 | - Update the "event loop time". |
499 | - Update the "event loop time". |
496 | - Calculate for how long to block. |
500 | - Calculate for how long to block. |
497 | - Block the process, waiting for any events. |
501 | - Block the process, waiting for any events. |
… | |
… | |
736 | =item bool ev_is_pending (ev_TYPE *watcher) |
740 | =item bool ev_is_pending (ev_TYPE *watcher) |
737 | |
741 | |
738 | Returns a true value iff the watcher is pending, (i.e. it has outstanding |
742 | Returns a true value iff the watcher is pending, (i.e. it has outstanding |
739 | events but its callback has not yet been invoked). As long as a watcher |
743 | events but its callback has not yet been invoked). As long as a watcher |
740 | is pending (but not active) you must not call an init function on it (but |
744 | is pending (but not active) you must not call an init function on it (but |
741 | C<ev_TYPE_set> is safe) and you must make sure the watcher is available to |
745 | C<ev_TYPE_set> is safe), you must not change its priority, and you must |
742 | libev (e.g. you cnanot C<free ()> it). |
746 | make sure the watcher is available to libev (e.g. you cannot C<free ()> |
|
|
747 | it). |
743 | |
748 | |
744 | =item callback ev_cb (ev_TYPE *watcher) |
749 | =item callback ev_cb (ev_TYPE *watcher) |
745 | |
750 | |
746 | Returns the callback currently set on the watcher. |
751 | Returns the callback currently set on the watcher. |
747 | |
752 | |
… | |
… | |
766 | watchers on the same event and make sure one is called first. |
771 | watchers on the same event and make sure one is called first. |
767 | |
772 | |
768 | If you need to suppress invocation when higher priority events are pending |
773 | If you need to suppress invocation when higher priority events are pending |
769 | you need to look at C<ev_idle> watchers, which provide this functionality. |
774 | you need to look at C<ev_idle> watchers, which provide this functionality. |
770 | |
775 | |
|
|
776 | You I<must not> change the priority of a watcher as long as it is active or |
|
|
777 | pending. |
|
|
778 | |
771 | The default priority used by watchers when no priority has been set is |
779 | The default priority used by watchers when no priority has been set is |
772 | always C<0>, which is supposed to not be too high and not be too low :). |
780 | always C<0>, which is supposed to not be too high and not be too low :). |
773 | |
781 | |
774 | Setting a priority outside the range of C<EV_MINPRI> to C<EV_MAXPRI> is |
782 | Setting a priority outside the range of C<EV_MINPRI> to C<EV_MAXPRI> is |
775 | fine, as long as you do not mind that the priority value you query might |
783 | fine, as long as you do not mind that the priority value you query might |
776 | or might not have been adjusted to be within valid range. |
784 | or might not have been adjusted to be within valid range. |
|
|
785 | |
|
|
786 | =item ev_invoke (loop, ev_TYPE *watcher, int revents) |
|
|
787 | |
|
|
788 | Invoke the C<watcher> with the given C<loop> and C<revents>. Neither |
|
|
789 | C<loop> nor C<revents> need to be valid as long as the watcher callback |
|
|
790 | can deal with that fact. |
|
|
791 | |
|
|
792 | =item int ev_clear_pending (loop, ev_TYPE *watcher) |
|
|
793 | |
|
|
794 | If the watcher is pending, this function returns clears its pending status |
|
|
795 | and returns its C<revents> bitset (as if its callback was invoked). If the |
|
|
796 | watcher isn't pending it does nothing and returns C<0>. |
777 | |
797 | |
778 | =back |
798 | =back |
779 | |
799 | |
780 | |
800 | |
781 | =head2 ASSOCIATING CUSTOM DATA WITH A WATCHER |
801 | =head2 ASSOCIATING CUSTOM DATA WITH A WATCHER |
… | |
… | |
1057 | but on wallclock time (absolute time). You can tell a periodic watcher |
1077 | but on wallclock time (absolute time). You can tell a periodic watcher |
1058 | to trigger "at" some specific point in time. For example, if you tell a |
1078 | to trigger "at" some specific point in time. For example, if you tell a |
1059 | periodic watcher to trigger in 10 seconds (by specifiying e.g. C<ev_now () |
1079 | periodic watcher to trigger in 10 seconds (by specifiying e.g. C<ev_now () |
1060 | + 10.>) and then reset your system clock to the last year, then it will |
1080 | + 10.>) and then reset your system clock to the last year, then it will |
1061 | take a year to trigger the event (unlike an C<ev_timer>, which would trigger |
1081 | take a year to trigger the event (unlike an C<ev_timer>, which would trigger |
1062 | roughly 10 seconds later and of course not if you reset your system time |
1082 | roughly 10 seconds later). |
1063 | again). |
|
|
1064 | |
1083 | |
1065 | They can also be used to implement vastly more complex timers, such as |
1084 | They can also be used to implement vastly more complex timers, such as |
1066 | triggering an event on eahc midnight, local time. |
1085 | triggering an event on each midnight, local time or other, complicated, |
|
|
1086 | rules. |
1067 | |
1087 | |
1068 | As with timers, the callback is guarenteed to be invoked only when the |
1088 | As with timers, the callback is guarenteed to be invoked only when the |
1069 | time (C<at>) has been passed, but if multiple periodic timers become ready |
1089 | time (C<at>) has been passed, but if multiple periodic timers become ready |
1070 | during the same loop iteration then order of execution is undefined. |
1090 | during the same loop iteration then order of execution is undefined. |
1071 | |
1091 | |
… | |
… | |
1078 | Lots of arguments, lets sort it out... There are basically three modes of |
1098 | Lots of arguments, lets sort it out... There are basically three modes of |
1079 | operation, and we will explain them from simplest to complex: |
1099 | operation, and we will explain them from simplest to complex: |
1080 | |
1100 | |
1081 | =over 4 |
1101 | =over 4 |
1082 | |
1102 | |
1083 | =item * absolute timer (interval = reschedule_cb = 0) |
1103 | =item * absolute timer (at = time, interval = reschedule_cb = 0) |
1084 | |
1104 | |
1085 | In this configuration the watcher triggers an event at the wallclock time |
1105 | In this configuration the watcher triggers an event at the wallclock time |
1086 | C<at> and doesn't repeat. It will not adjust when a time jump occurs, |
1106 | C<at> and doesn't repeat. It will not adjust when a time jump occurs, |
1087 | that is, if it is to be run at January 1st 2011 then it will run when the |
1107 | that is, if it is to be run at January 1st 2011 then it will run when the |
1088 | system time reaches or surpasses this time. |
1108 | system time reaches or surpasses this time. |
1089 | |
1109 | |
1090 | =item * non-repeating interval timer (interval > 0, reschedule_cb = 0) |
1110 | =item * non-repeating interval timer (at = offset, interval > 0, reschedule_cb = 0) |
1091 | |
1111 | |
1092 | In this mode the watcher will always be scheduled to time out at the next |
1112 | In this mode the watcher will always be scheduled to time out at the next |
1093 | C<at + N * interval> time (for some integer N) and then repeat, regardless |
1113 | C<at + N * interval> time (for some integer N, which can also be negative) |
1094 | of any time jumps. |
1114 | and then repeat, regardless of any time jumps. |
1095 | |
1115 | |
1096 | This can be used to create timers that do not drift with respect to system |
1116 | This can be used to create timers that do not drift with respect to system |
1097 | time: |
1117 | time: |
1098 | |
1118 | |
1099 | ev_periodic_set (&periodic, 0., 3600., 0); |
1119 | ev_periodic_set (&periodic, 0., 3600., 0); |
… | |
… | |
1105 | |
1125 | |
1106 | Another way to think about it (for the mathematically inclined) is that |
1126 | Another way to think about it (for the mathematically inclined) is that |
1107 | C<ev_periodic> will try to run the callback in this mode at the next possible |
1127 | C<ev_periodic> will try to run the callback in this mode at the next possible |
1108 | time where C<time = at (mod interval)>, regardless of any time jumps. |
1128 | time where C<time = at (mod interval)>, regardless of any time jumps. |
1109 | |
1129 | |
|
|
1130 | For numerical stability it is preferable that the C<at> value is near |
|
|
1131 | C<ev_now ()> (the current time), but there is no range requirement for |
|
|
1132 | this value. |
|
|
1133 | |
1110 | =item * manual reschedule mode (reschedule_cb = callback) |
1134 | =item * manual reschedule mode (at and interval ignored, reschedule_cb = callback) |
1111 | |
1135 | |
1112 | In this mode the values for C<interval> and C<at> are both being |
1136 | In this mode the values for C<interval> and C<at> are both being |
1113 | ignored. Instead, each time the periodic watcher gets scheduled, the |
1137 | ignored. Instead, each time the periodic watcher gets scheduled, the |
1114 | reschedule callback will be called with the watcher as first, and the |
1138 | reschedule callback will be called with the watcher as first, and the |
1115 | current time as second argument. |
1139 | current time as second argument. |
1116 | |
1140 | |
1117 | NOTE: I<This callback MUST NOT stop or destroy any periodic watcher, |
1141 | NOTE: I<This callback MUST NOT stop or destroy any periodic watcher, |
1118 | ever, or make any event loop modifications>. If you need to stop it, |
1142 | ever, or make any event loop modifications>. If you need to stop it, |
1119 | return C<now + 1e30> (or so, fudge fudge) and stop it afterwards (e.g. by |
1143 | return C<now + 1e30> (or so, fudge fudge) and stop it afterwards (e.g. by |
1120 | starting a prepare watcher). |
1144 | starting an C<ev_prepare> watcher, which is legal). |
1121 | |
1145 | |
1122 | Its prototype is C<ev_tstamp (*reschedule_cb)(struct ev_periodic *w, |
1146 | Its prototype is C<ev_tstamp (*reschedule_cb)(struct ev_periodic *w, |
1123 | ev_tstamp now)>, e.g.: |
1147 | ev_tstamp now)>, e.g.: |
1124 | |
1148 | |
1125 | static ev_tstamp my_rescheduler (struct ev_periodic *w, ev_tstamp now) |
1149 | static ev_tstamp my_rescheduler (struct ev_periodic *w, ev_tstamp now) |
… | |
… | |
1147 | |
1171 | |
1148 | Simply stops and restarts the periodic watcher again. This is only useful |
1172 | Simply stops and restarts the periodic watcher again. This is only useful |
1149 | when you changed some parameters or the reschedule callback would return |
1173 | when you changed some parameters or the reschedule callback would return |
1150 | a different time than the last time it was called (e.g. in a crond like |
1174 | a different time than the last time it was called (e.g. in a crond like |
1151 | program when the crontabs have changed). |
1175 | program when the crontabs have changed). |
|
|
1176 | |
|
|
1177 | =item ev_tstamp offset [read-write] |
|
|
1178 | |
|
|
1179 | When repeating, this contains the offset value, otherwise this is the |
|
|
1180 | absolute point in time (the C<at> value passed to C<ev_periodic_set>). |
|
|
1181 | |
|
|
1182 | Can be modified any time, but changes only take effect when the periodic |
|
|
1183 | timer fires or C<ev_periodic_again> is being called. |
1152 | |
1184 | |
1153 | =item ev_tstamp interval [read-write] |
1185 | =item ev_tstamp interval [read-write] |
1154 | |
1186 | |
1155 | The current interval value. Can be modified any time, but changes only |
1187 | The current interval value. Can be modified any time, but changes only |
1156 | take effect when the periodic timer fires or C<ev_periodic_again> is being |
1188 | take effect when the periodic timer fires or C<ev_periodic_again> is being |
… | |
… | |
1465 | with priority higher than or equal to the event loop and one coroutine |
1497 | with priority higher than or equal to the event loop and one coroutine |
1466 | of lower priority, but only once, using idle watchers to keep the event |
1498 | of lower priority, but only once, using idle watchers to keep the event |
1467 | loop from blocking if lower-priority coroutines are active, thus mapping |
1499 | loop from blocking if lower-priority coroutines are active, thus mapping |
1468 | low-priority coroutines to idle/background tasks). |
1500 | low-priority coroutines to idle/background tasks). |
1469 | |
1501 | |
|
|
1502 | It is recommended to give C<ev_check> watchers highest (C<EV_MAXPRI>) |
|
|
1503 | priority, to ensure that they are being run before any other watchers |
|
|
1504 | after the poll. Also, C<ev_check> watchers (and C<ev_prepare> watchers, |
|
|
1505 | too) should not activate ("feed") events into libev. While libev fully |
|
|
1506 | supports this, they will be called before other C<ev_check> watchers did |
|
|
1507 | their job. As C<ev_check> watchers are often used to embed other event |
|
|
1508 | loops those other event loops might be in an unusable state until their |
|
|
1509 | C<ev_check> watcher ran (always remind yourself to coexist peacefully with |
|
|
1510 | others). |
|
|
1511 | |
1470 | =over 4 |
1512 | =over 4 |
1471 | |
1513 | |
1472 | =item ev_prepare_init (ev_prepare *, callback) |
1514 | =item ev_prepare_init (ev_prepare *, callback) |
1473 | |
1515 | |
1474 | =item ev_check_init (ev_check *, callback) |
1516 | =item ev_check_init (ev_check *, callback) |
… | |
… | |
1477 | parameters of any kind. There are C<ev_prepare_set> and C<ev_check_set> |
1519 | parameters of any kind. There are C<ev_prepare_set> and C<ev_check_set> |
1478 | macros, but using them is utterly, utterly and completely pointless. |
1520 | macros, but using them is utterly, utterly and completely pointless. |
1479 | |
1521 | |
1480 | =back |
1522 | =back |
1481 | |
1523 | |
1482 | Example: To include a library such as adns, you would add IO watchers |
1524 | There are a number of principal ways to embed other event loops or modules |
1483 | and a timeout watcher in a prepare handler, as required by libadns, and |
1525 | into libev. Here are some ideas on how to include libadns into libev |
|
|
1526 | (there is a Perl module named C<EV::ADNS> that does this, which you could |
|
|
1527 | use for an actually working example. Another Perl module named C<EV::Glib> |
|
|
1528 | embeds a Glib main context into libev, and finally, C<Glib::EV> embeds EV |
|
|
1529 | into the Glib event loop). |
|
|
1530 | |
|
|
1531 | Method 1: Add IO watchers and a timeout watcher in a prepare handler, |
1484 | in a check watcher, destroy them and call into libadns. What follows is |
1532 | and in a check watcher, destroy them and call into libadns. What follows |
1485 | pseudo-code only of course: |
1533 | is pseudo-code only of course. This requires you to either use a low |
|
|
1534 | priority for the check watcher or use C<ev_clear_pending> explicitly, as |
|
|
1535 | the callbacks for the IO/timeout watchers might not have been called yet. |
1486 | |
1536 | |
1487 | static ev_io iow [nfd]; |
1537 | static ev_io iow [nfd]; |
1488 | static ev_timer tw; |
1538 | static ev_timer tw; |
1489 | |
1539 | |
1490 | static void |
1540 | static void |
1491 | io_cb (ev_loop *loop, ev_io *w, int revents) |
1541 | io_cb (ev_loop *loop, ev_io *w, int revents) |
1492 | { |
1542 | { |
1493 | // set the relevant poll flags |
|
|
1494 | // could also call adns_processreadable etc. here |
|
|
1495 | struct pollfd *fd = (struct pollfd *)w->data; |
|
|
1496 | if (revents & EV_READ ) fd->revents |= fd->events & POLLIN; |
|
|
1497 | if (revents & EV_WRITE) fd->revents |= fd->events & POLLOUT; |
|
|
1498 | } |
1543 | } |
1499 | |
1544 | |
1500 | // create io watchers for each fd and a timer before blocking |
1545 | // create io watchers for each fd and a timer before blocking |
1501 | static void |
1546 | static void |
1502 | adns_prepare_cb (ev_loop *loop, ev_prepare *w, int revents) |
1547 | adns_prepare_cb (ev_loop *loop, ev_prepare *w, int revents) |
… | |
… | |
1508 | |
1553 | |
1509 | /* the callback is illegal, but won't be called as we stop during check */ |
1554 | /* the callback is illegal, but won't be called as we stop during check */ |
1510 | ev_timer_init (&tw, 0, timeout * 1e-3); |
1555 | ev_timer_init (&tw, 0, timeout * 1e-3); |
1511 | ev_timer_start (loop, &tw); |
1556 | ev_timer_start (loop, &tw); |
1512 | |
1557 | |
1513 | // create on ev_io per pollfd |
1558 | // create one ev_io per pollfd |
1514 | for (int i = 0; i < nfd; ++i) |
1559 | for (int i = 0; i < nfd; ++i) |
1515 | { |
1560 | { |
1516 | ev_io_init (iow + i, io_cb, fds [i].fd, |
1561 | ev_io_init (iow + i, io_cb, fds [i].fd, |
1517 | ((fds [i].events & POLLIN ? EV_READ : 0) |
1562 | ((fds [i].events & POLLIN ? EV_READ : 0) |
1518 | | (fds [i].events & POLLOUT ? EV_WRITE : 0))); |
1563 | | (fds [i].events & POLLOUT ? EV_WRITE : 0))); |
1519 | |
1564 | |
1520 | fds [i].revents = 0; |
1565 | fds [i].revents = 0; |
1521 | iow [i].data = fds + i; |
|
|
1522 | ev_io_start (loop, iow + i); |
1566 | ev_io_start (loop, iow + i); |
1523 | } |
1567 | } |
1524 | } |
1568 | } |
1525 | |
1569 | |
1526 | // stop all watchers after blocking |
1570 | // stop all watchers after blocking |
… | |
… | |
1528 | adns_check_cb (ev_loop *loop, ev_check *w, int revents) |
1572 | adns_check_cb (ev_loop *loop, ev_check *w, int revents) |
1529 | { |
1573 | { |
1530 | ev_timer_stop (loop, &tw); |
1574 | ev_timer_stop (loop, &tw); |
1531 | |
1575 | |
1532 | for (int i = 0; i < nfd; ++i) |
1576 | for (int i = 0; i < nfd; ++i) |
|
|
1577 | { |
|
|
1578 | // set the relevant poll flags |
|
|
1579 | // could also call adns_processreadable etc. here |
|
|
1580 | struct pollfd *fd = fds + i; |
|
|
1581 | int revents = ev_clear_pending (iow + i); |
|
|
1582 | if (revents & EV_READ ) fd->revents |= fd->events & POLLIN; |
|
|
1583 | if (revents & EV_WRITE) fd->revents |= fd->events & POLLOUT; |
|
|
1584 | |
|
|
1585 | // now stop the watcher |
1533 | ev_io_stop (loop, iow + i); |
1586 | ev_io_stop (loop, iow + i); |
|
|
1587 | } |
1534 | |
1588 | |
1535 | adns_afterpoll (adns, fds, nfd, timeval_from (ev_now (loop)); |
1589 | adns_afterpoll (adns, fds, nfd, timeval_from (ev_now (loop)); |
|
|
1590 | } |
|
|
1591 | |
|
|
1592 | Method 2: This would be just like method 1, but you run C<adns_afterpoll> |
|
|
1593 | in the prepare watcher and would dispose of the check watcher. |
|
|
1594 | |
|
|
1595 | Method 3: If the module to be embedded supports explicit event |
|
|
1596 | notification (adns does), you can also make use of the actual watcher |
|
|
1597 | callbacks, and only destroy/create the watchers in the prepare watcher. |
|
|
1598 | |
|
|
1599 | static void |
|
|
1600 | timer_cb (EV_P_ ev_timer *w, int revents) |
|
|
1601 | { |
|
|
1602 | adns_state ads = (adns_state)w->data; |
|
|
1603 | update_now (EV_A); |
|
|
1604 | |
|
|
1605 | adns_processtimeouts (ads, &tv_now); |
|
|
1606 | } |
|
|
1607 | |
|
|
1608 | static void |
|
|
1609 | io_cb (EV_P_ ev_io *w, int revents) |
|
|
1610 | { |
|
|
1611 | adns_state ads = (adns_state)w->data; |
|
|
1612 | update_now (EV_A); |
|
|
1613 | |
|
|
1614 | if (revents & EV_READ ) adns_processreadable (ads, w->fd, &tv_now); |
|
|
1615 | if (revents & EV_WRITE) adns_processwriteable (ads, w->fd, &tv_now); |
|
|
1616 | } |
|
|
1617 | |
|
|
1618 | // do not ever call adns_afterpoll |
|
|
1619 | |
|
|
1620 | Method 4: Do not use a prepare or check watcher because the module you |
|
|
1621 | want to embed is too inflexible to support it. Instead, youc na override |
|
|
1622 | their poll function. The drawback with this solution is that the main |
|
|
1623 | loop is now no longer controllable by EV. The C<Glib::EV> module does |
|
|
1624 | this. |
|
|
1625 | |
|
|
1626 | static gint |
|
|
1627 | event_poll_func (GPollFD *fds, guint nfds, gint timeout) |
|
|
1628 | { |
|
|
1629 | int got_events = 0; |
|
|
1630 | |
|
|
1631 | for (n = 0; n < nfds; ++n) |
|
|
1632 | // create/start io watcher that sets the relevant bits in fds[n] and increment got_events |
|
|
1633 | |
|
|
1634 | if (timeout >= 0) |
|
|
1635 | // create/start timer |
|
|
1636 | |
|
|
1637 | // poll |
|
|
1638 | ev_loop (EV_A_ 0); |
|
|
1639 | |
|
|
1640 | // stop timer again |
|
|
1641 | if (timeout >= 0) |
|
|
1642 | ev_timer_stop (EV_A_ &to); |
|
|
1643 | |
|
|
1644 | // stop io watchers again - their callbacks should have set |
|
|
1645 | for (n = 0; n < nfds; ++n) |
|
|
1646 | ev_io_stop (EV_A_ iow [n]); |
|
|
1647 | |
|
|
1648 | return got_events; |
1536 | } |
1649 | } |
1537 | |
1650 | |
1538 | |
1651 | |
1539 | =head2 C<ev_embed> - when one backend isn't enough... |
1652 | =head2 C<ev_embed> - when one backend isn't enough... |
1540 | |
1653 | |
… | |
… | |
1749 | This automatically includes F<ev.h> and puts all of its definitions (many |
1862 | This automatically includes F<ev.h> and puts all of its definitions (many |
1750 | of them macros) into the global namespace. All C++ specific things are |
1863 | of them macros) into the global namespace. All C++ specific things are |
1751 | put into the C<ev> namespace. It should support all the same embedding |
1864 | put into the C<ev> namespace. It should support all the same embedding |
1752 | options as F<ev.h>, most notably C<EV_MULTIPLICITY>. |
1865 | options as F<ev.h>, most notably C<EV_MULTIPLICITY>. |
1753 | |
1866 | |
1754 | Care has been taken to keep the overhead low. The only data member added |
1867 | Care has been taken to keep the overhead low. The only data member the C++ |
1755 | to the C-style watchers is the event loop the watcher is associated with |
1868 | classes add (compared to plain C-style watchers) is the event loop pointer |
1756 | (or no additional members at all if you disable C<EV_MULTIPLICITY> when |
1869 | that the watcher is associated with (or no additional members at all if |
1757 | embedding libev). |
1870 | you disable C<EV_MULTIPLICITY> when embedding libev). |
1758 | |
1871 | |
1759 | Currently, functions and static and non-static member functions can be |
1872 | Currently, functions, and static and non-static member functions can be |
1760 | used as callbacks. Other types should be easy to add as long as they only |
1873 | used as callbacks. Other types should be easy to add as long as they only |
1761 | need one additional pointer for context. If you need support for other |
1874 | need one additional pointer for context. If you need support for other |
1762 | types of functors please contact the author (preferably after implementing |
1875 | types of functors please contact the author (preferably after implementing |
1763 | it). |
1876 | it). |
1764 | |
1877 | |
… | |
… | |
1828 | |
1941 | |
1829 | myclass obj; |
1942 | myclass obj; |
1830 | ev::io iow; |
1943 | ev::io iow; |
1831 | iow.set <myclass, &myclass::io_cb> (&obj); |
1944 | iow.set <myclass, &myclass::io_cb> (&obj); |
1832 | |
1945 | |
1833 | =item w->set (void (*function)(watcher &w, int), void *data = 0) |
1946 | =item w->set<function> (void *data = 0) |
1834 | |
1947 | |
1835 | Also sets a callback, but uses a static method or plain function as |
1948 | Also sets a callback, but uses a static method or plain function as |
1836 | callback. The optional C<data> argument will be stored in the watcher's |
1949 | callback. The optional C<data> argument will be stored in the watcher's |
1837 | C<data> member and is free for you to use. |
1950 | C<data> member and is free for you to use. |
1838 | |
1951 | |
|
|
1952 | The prototype of the C<function> must be C<void (*)(ev::TYPE &w, int)>. |
|
|
1953 | |
1839 | See the method-C<set> above for more details. |
1954 | See the method-C<set> above for more details. |
|
|
1955 | |
|
|
1956 | Example: |
|
|
1957 | |
|
|
1958 | static void io_cb (ev::io &w, int revents) { } |
|
|
1959 | iow.set <io_cb> (); |
1840 | |
1960 | |
1841 | =item w->set (struct ev_loop *) |
1961 | =item w->set (struct ev_loop *) |
1842 | |
1962 | |
1843 | Associates a different C<struct ev_loop> with this watcher. You can only |
1963 | Associates a different C<struct ev_loop> with this watcher. You can only |
1844 | do this when the watcher is inactive (and not pending either). |
1964 | do this when the watcher is inactive (and not pending either). |