… | |
… | |
131 | .\} |
131 | .\} |
132 | .rm #[ #] #H #V #F C |
132 | .rm #[ #] #H #V #F C |
133 | .\" ======================================================================== |
133 | .\" ======================================================================== |
134 | .\" |
134 | .\" |
135 | .IX Title "LIBEV 3" |
135 | .IX Title "LIBEV 3" |
136 | .TH LIBEV 3 "2020-01-22" "libev-4.31" "libev - high performance full featured event loop" |
136 | .TH LIBEV 3 "2020-07-12" "libev-4.33" "libev - high performance full featured event loop" |
137 | .\" For nroff, turn off justification. Always turn off hyphenation; it makes |
137 | .\" For nroff, turn off justification. Always turn off hyphenation; it makes |
138 | .\" way too many mistakes in technical documents. |
138 | .\" way too many mistakes in technical documents. |
139 | .if n .ad l |
139 | .if n .ad l |
140 | .nh |
140 | .nh |
141 | .SH "NAME" |
141 | .SH "NAME" |
… | |
… | |
1532 | therefore a good idea to always call its \f(CW\*(C`ev_TYPE_stop\*(C'\fR function. |
1532 | therefore a good idea to always call its \f(CW\*(C`ev_TYPE_stop\*(C'\fR function. |
1533 | .IP "bool ev_is_active (ev_TYPE *watcher)" 4 |
1533 | .IP "bool ev_is_active (ev_TYPE *watcher)" 4 |
1534 | .IX Item "bool ev_is_active (ev_TYPE *watcher)" |
1534 | .IX Item "bool ev_is_active (ev_TYPE *watcher)" |
1535 | Returns a true value iff the watcher is active (i.e. it has been started |
1535 | Returns a true value iff the watcher is active (i.e. it has been started |
1536 | and not yet been stopped). As long as a watcher is active you must not modify |
1536 | and not yet been stopped). As long as a watcher is active you must not modify |
1537 | it. |
1537 | it unless documented otherwise. |
1538 | .IP "bool ev_is_pending (ev_TYPE *watcher)" 4 |
1538 | .IP "bool ev_is_pending (ev_TYPE *watcher)" 4 |
1539 | .IX Item "bool ev_is_pending (ev_TYPE *watcher)" |
1539 | .IX Item "bool ev_is_pending (ev_TYPE *watcher)" |
1540 | Returns a true value iff the watcher is pending, (i.e. it has outstanding |
1540 | Returns a true value iff the watcher is pending, (i.e. it has outstanding |
1541 | events but its callback has not yet been invoked). As long as a watcher |
1541 | events but its callback has not yet been invoked). As long as a watcher |
1542 | is pending (but not active) you must not call an init function on it (but |
1542 | is pending (but not active) you must not call an init function on it (but |
… | |
… | |
1772 | .PP |
1772 | .PP |
1773 | Most members are additionally marked with either \fI[read\-only]\fR, meaning |
1773 | Most members are additionally marked with either \fI[read\-only]\fR, meaning |
1774 | that, while the watcher is active, you can look at the member and expect |
1774 | that, while the watcher is active, you can look at the member and expect |
1775 | some sensible content, but you must not modify it (you can modify it while |
1775 | some sensible content, but you must not modify it (you can modify it while |
1776 | the watcher is stopped to your hearts content), or \fI[read\-write]\fR, which |
1776 | the watcher is stopped to your hearts content), or \fI[read\-write]\fR, which |
1777 | means you can expect it to have some sensible content while the watcher |
1777 | means you can expect it to have some sensible content while the watcher is |
1778 | is active, but you can also modify it. Modifying it may not do something |
1778 | active, but you can also modify it (within the same thread as the event |
|
|
1779 | loop, i.e. without creating data races). Modifying it may not do something |
1779 | sensible or take immediate effect (or do anything at all), but libev will |
1780 | sensible or take immediate effect (or do anything at all), but libev will |
1780 | not crash or malfunction in any way. |
1781 | not crash or malfunction in any way. |
1781 | .PP |
1782 | .PP |
1782 | In any case, the documentation for each member will explain what the |
1783 | In any case, the documentation for each member will explain what the |
1783 | effects are, and if there are any additional access restrictions. |
1784 | effects are, and if there are any additional access restrictions. |
… | |
… | |
1964 | supported, but not specially optimized \- if your program sometimes happens |
1965 | supported, but not specially optimized \- if your program sometimes happens |
1965 | to generate this combination this is fine, but if it is easy to avoid |
1966 | to generate this combination this is fine, but if it is easy to avoid |
1966 | starting an io watcher watching for no events you should do so. |
1967 | starting an io watcher watching for no events you should do so. |
1967 | .IP "ev_io_modify (ev_io *, int events)" 4 |
1968 | .IP "ev_io_modify (ev_io *, int events)" 4 |
1968 | .IX Item "ev_io_modify (ev_io *, int events)" |
1969 | .IX Item "ev_io_modify (ev_io *, int events)" |
1969 | Similar to \f(CW\*(C`ev_io_set\*(C'\fR, but only changes the event mask. Using this might |
1970 | Similar to \f(CW\*(C`ev_io_set\*(C'\fR, but only changes the requested events. Using this |
1970 | be faster with some backends, as libev can assume that the \f(CW\*(C`fd\*(C'\fR still |
1971 | might be faster with some backends, as libev can assume that the \f(CW\*(C`fd\*(C'\fR |
1971 | refers to the same underlying file description, something it cannot do |
1972 | still refers to the same underlying file description, something it cannot |
1972 | when using \f(CW\*(C`ev_io_set\*(C'\fR. |
1973 | do when using \f(CW\*(C`ev_io_set\*(C'\fR. |
1973 | .IP "int fd [no\-modify]" 4 |
1974 | .IP "int fd [no\-modify]" 4 |
1974 | .IX Item "int fd [no-modify]" |
1975 | .IX Item "int fd [no-modify]" |
1975 | The file descriptor being watched. While it can be read at any time, you |
1976 | The file descriptor being watched. While it can be read at any time, you |
1976 | must not modify this member even when the watcher is stopped \- always use |
1977 | must not modify this member even when the watcher is stopped \- always use |
1977 | \&\f(CW\*(C`ev_io_set\*(C'\fR for that. |
1978 | \&\f(CW\*(C`ev_io_set\*(C'\fR for that. |
… | |
… | |
4001 | .PP |
4002 | .PP |
4002 | First, you need to associate some data with the event loop: |
4003 | First, you need to associate some data with the event loop: |
4003 | .PP |
4004 | .PP |
4004 | .Vb 6 |
4005 | .Vb 6 |
4005 | \& typedef struct { |
4006 | \& typedef struct { |
4006 | \& mutex_t lock; /* global loop lock */ |
4007 | \& pthread_mutex_t lock; /* global loop lock */ |
|
|
4008 | \& pthread_t tid; |
|
|
4009 | \& pthread_cond_t invoke_cv; |
4007 | \& ev_async async_w; |
4010 | \& ev_async async_w; |
4008 | \& thread_t tid; |
|
|
4009 | \& cond_t invoke_cv; |
|
|
4010 | \& } userdata; |
4011 | \& } userdata; |
4011 | \& |
4012 | \& |
4012 | \& void prepare_loop (EV_P) |
4013 | \& void prepare_loop (EV_P) |
4013 | \& { |
4014 | \& { |
4014 | \& // for simplicity, we use a static userdata struct. |
4015 | \& // for simplicity, we use a static userdata struct. |
4015 | \& static userdata u; |
4016 | \& static userdata u; |
4016 | \& |
4017 | \& |
4017 | \& ev_async_init (&u\->async_w, async_cb); |
4018 | \& ev_async_init (&u.async_w, async_cb); |
4018 | \& ev_async_start (EV_A_ &u\->async_w); |
4019 | \& ev_async_start (EV_A_ &u.async_w); |
4019 | \& |
4020 | \& |
4020 | \& pthread_mutex_init (&u\->lock, 0); |
4021 | \& pthread_mutex_init (&u.lock, 0); |
4021 | \& pthread_cond_init (&u\->invoke_cv, 0); |
4022 | \& pthread_cond_init (&u.invoke_cv, 0); |
4022 | \& |
4023 | \& |
4023 | \& // now associate this with the loop |
4024 | \& // now associate this with the loop |
4024 | \& ev_set_userdata (EV_A_ u); |
4025 | \& ev_set_userdata (EV_A_ &u); |
4025 | \& ev_set_invoke_pending_cb (EV_A_ l_invoke); |
4026 | \& ev_set_invoke_pending_cb (EV_A_ l_invoke); |
4026 | \& ev_set_loop_release_cb (EV_A_ l_release, l_acquire); |
4027 | \& ev_set_loop_release_cb (EV_A_ l_release, l_acquire); |
4027 | \& |
4028 | \& |
4028 | \& // then create the thread running ev_run |
4029 | \& // then create the thread running ev_run |
4029 | \& pthread_create (&u\->tid, 0, l_run, EV_A); |
4030 | \& pthread_create (&u.tid, 0, l_run, EV_A); |
4030 | \& } |
4031 | \& } |
4031 | .Ve |
4032 | .Ve |
4032 | .PP |
4033 | .PP |
4033 | The callback for the \f(CW\*(C`ev_async\*(C'\fR watcher does nothing: the watcher is used |
4034 | The callback for the \f(CW\*(C`ev_async\*(C'\fR watcher does nothing: the watcher is used |
4034 | solely to wake up the event loop so it takes notice of any new watchers |
4035 | solely to wake up the event loop so it takes notice of any new watchers |