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Comparing libev/ev.pod (file contents):
Revision 1.217 by root, Mon Nov 17 03:37:08 2008 UTC vs.
Revision 1.222 by root, Sun Dec 7 15:43:43 2008 UTC

43 43
44 int 44 int
45 main (void) 45 main (void)
46 { 46 {
47 // use the default event loop unless you have special needs 47 // use the default event loop unless you have special needs
48 ev_loop *loop = ev_default_loop (0); 48 struct ev_loop *loop = ev_default_loop (0);
49 49
50 // initialise an io watcher, then start it 50 // initialise an io watcher, then start it
51 // this one will watch for stdin to become readable 51 // this one will watch for stdin to become readable
52 ev_io_init (&stdin_watcher, stdin_cb, /*STDIN_FILENO*/ 0, EV_READ); 52 ev_io_init (&stdin_watcher, stdin_cb, /*STDIN_FILENO*/ 0, EV_READ);
53 ev_io_start (loop, &stdin_watcher); 53 ev_io_start (loop, &stdin_watcher);
2012the process. The exception are C<ev_stat> watchers - those call C<stat 2012the process. The exception are C<ev_stat> watchers - those call C<stat
2013()>, which is a synchronous operation. 2013()>, which is a synchronous operation.
2014 2014
2015For local paths, this usually doesn't matter: unless the system is very 2015For local paths, this usually doesn't matter: unless the system is very
2016busy or the intervals between stat's are large, a stat call will be fast, 2016busy or the intervals between stat's are large, a stat call will be fast,
2017as the path data is suually in memory already (except when starting the 2017as the path data is usually in memory already (except when starting the
2018watcher). 2018watcher).
2019 2019
2020For networked file systems, calling C<stat ()> can block an indefinite 2020For networked file systems, calling C<stat ()> can block an indefinite
2021time due to network issues, and even under good conditions, a stat call 2021time due to network issues, and even under good conditions, a stat call
2022often takes multiple milliseconds. 2022often takes multiple milliseconds.
2891 2891
2892 myclass obj; 2892 myclass obj;
2893 ev::io iow; 2893 ev::io iow;
2894 iow.set <myclass, &myclass::io_cb> (&obj); 2894 iow.set <myclass, &myclass::io_cb> (&obj);
2895 2895
2896=item w->set (object *)
2897
2898This is an B<experimental> feature that might go away in a future version.
2899
2900This is a variation of a method callback - leaving out the method to call
2901will default the method to C<operator ()>, which makes it possible to use
2902functor objects without having to manually specify the C<operator ()> all
2903the time. Incidentally, you can then also leave out the template argument
2904list.
2905
2906The C<operator ()> method prototype must be C<void operator ()(watcher &w,
2907int revents)>.
2908
2909See the method-C<set> above for more details.
2910
2911Example: use a functor object as callback.
2912
2913 struct myfunctor
2914 {
2915 void operator() (ev::io &w, int revents)
2916 {
2917 ...
2918 }
2919 }
2920
2921 myfunctor f;
2922
2923 ev::io w;
2924 w.set (&f);
2925
2896=item w->set<function> (void *data = 0) 2926=item w->set<function> (void *data = 0)
2897 2927
2898Also sets a callback, but uses a static method or plain function as 2928Also sets a callback, but uses a static method or plain function as
2899callback. The optional C<data> argument will be stored in the watcher's 2929callback. The optional C<data> argument will be stored in the watcher's
2900C<data> member and is free for you to use. 2930C<data> member and is free for you to use.
2999Tony Arcieri has written a ruby extension that offers access to a subset 3029Tony Arcieri has written a ruby extension that offers access to a subset
3000of the libev API and adds file handle abstractions, asynchronous DNS and 3030of the libev API and adds file handle abstractions, asynchronous DNS and
3001more on top of it. It can be found via gem servers. Its homepage is at 3031more on top of it. It can be found via gem servers. Its homepage is at
3002L<http://rev.rubyforge.org/>. 3032L<http://rev.rubyforge.org/>.
3003 3033
3034Roger Pack reports that using the link order C<-lws2_32 -lmsvcrt-ruby-190>
3035makes rev work even on mingw.
3036
3004=item D 3037=item D
3005 3038
3006Leandro Lucarella has written a D language binding (F<ev.d>) for libev, to 3039Leandro Lucarella has written a D language binding (F<ev.d>) for libev, to
3007be found at L<http://proj.llucax.com.ar/wiki/evd>. 3040be found at L<http://proj.llucax.com.ar/wiki/evd>.
3008 3041
3184keeps libev from including F<config.h>, and it also defines dummy 3217keeps libev from including F<config.h>, and it also defines dummy
3185implementations for some libevent functions (such as logging, which is not 3218implementations for some libevent functions (such as logging, which is not
3186supported). It will also not define any of the structs usually found in 3219supported). It will also not define any of the structs usually found in
3187F<event.h> that are not directly supported by the libev core alone. 3220F<event.h> that are not directly supported by the libev core alone.
3188 3221
3222In stanbdalone mode, libev will still try to automatically deduce the
3223configuration, but has to be more conservative.
3224
3189=item EV_USE_MONOTONIC 3225=item EV_USE_MONOTONIC
3190 3226
3191If defined to be C<1>, libev will try to detect the availability of the 3227If defined to be C<1>, libev will try to detect the availability of the
3192monotonic clock option at both compile time and runtime. Otherwise no use 3228monotonic clock option at both compile time and runtime. Otherwise no
3193of the monotonic clock option will be attempted. If you enable this, you 3229use of the monotonic clock option will be attempted. If you enable this,
3194usually have to link against librt or something similar. Enabling it when 3230you usually have to link against librt or something similar. Enabling it
3195the functionality isn't available is safe, though, although you have 3231when the functionality isn't available is safe, though, although you have
3196to make sure you link against any libraries where the C<clock_gettime> 3232to make sure you link against any libraries where the C<clock_gettime>
3197function is hiding in (often F<-lrt>). 3233function is hiding in (often F<-lrt>). See also C<EV_USE_CLOCK_SYSCALL>.
3198 3234
3199=item EV_USE_REALTIME 3235=item EV_USE_REALTIME
3200 3236
3201If defined to be C<1>, libev will try to detect the availability of the 3237If defined to be C<1>, libev will try to detect the availability of the
3202real-time clock option at compile time (and assume its availability at 3238real-time clock option at compile time (and assume its availability at
3203runtime if successful). Otherwise no use of the real-time clock option will 3239runtime if successful). Otherwise no use of the real-time clock option will
3204be attempted. This effectively replaces C<gettimeofday> by C<clock_get 3240be attempted. This effectively replaces C<gettimeofday> by C<clock_get
3205(CLOCK_REALTIME, ...)> and will not normally affect correctness. See the 3241(CLOCK_REALTIME, ...)> and will not normally affect correctness. See the
3206note about libraries in the description of C<EV_USE_MONOTONIC>, though. 3242note about libraries in the description of C<EV_USE_MONOTONIC>, though.
3207 3243
3244=item EV_USE_CLOCK_SYSCALL
3245
3246If defined to be C<1>, libev will try to use a direct syscall instead
3247of calling the system-provided C<clock_gettime> function. This option
3248exists because on GNU/Linux, C<clock_gettime> is in C<librt>, but C<librt>
3249unconditionally pulls in C<libpthread>, slowing down single-threaded
3250programs needlessly. Using a direct syscall is slightly slower (in
3251theory), because no optimised vdso implementation can be used, but avoids
3252the pthread dependency. Defaults to C<1> on GNU/Linux with glibc 2.x or
3253higher, as it simplifies linking (no need for C<-lrt>).
3254
3208=item EV_USE_NANOSLEEP 3255=item EV_USE_NANOSLEEP
3209 3256
3210If defined to be C<1>, libev will assume that C<nanosleep ()> is available 3257If defined to be C<1>, libev will assume that C<nanosleep ()> is available
3211and will use it for delays. Otherwise it will use C<select ()>. 3258and will use it for delays. Otherwise it will use C<select ()>.
3212 3259
3227 3274
3228=item EV_SELECT_USE_FD_SET 3275=item EV_SELECT_USE_FD_SET
3229 3276
3230If defined to C<1>, then the select backend will use the system C<fd_set> 3277If defined to C<1>, then the select backend will use the system C<fd_set>
3231structure. This is useful if libev doesn't compile due to a missing 3278structure. This is useful if libev doesn't compile due to a missing
3232C<NFDBITS> or C<fd_mask> definition or it mis-guesses the bitset layout on 3279C<NFDBITS> or C<fd_mask> definition or it mis-guesses the bitset layout
3233exotic systems. This usually limits the range of file descriptors to some 3280on exotic systems. This usually limits the range of file descriptors to
3234low limit such as 1024 or might have other limitations (winsocket only 3281some low limit such as 1024 or might have other limitations (winsocket
3235allows 64 sockets). The C<FD_SETSIZE> macro, set before compilation, might 3282only allows 64 sockets). The C<FD_SETSIZE> macro, set before compilation,
3236influence the size of the C<fd_set> used. 3283configures the maximum size of the C<fd_set>.
3237 3284
3238=item EV_SELECT_IS_WINSOCKET 3285=item EV_SELECT_IS_WINSOCKET
3239 3286
3240When defined to C<1>, the select backend will assume that 3287When defined to C<1>, the select backend will assume that
3241select/socket/connect etc. don't understand file descriptors but 3288select/socket/connect etc. don't understand file descriptors but

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