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Comparing libev/ev.pod (file contents):
Revision 1.322 by root, Sun Oct 24 17:58:41 2010 UTC vs.
Revision 1.332 by root, Sun Oct 24 23:30:23 2010 UTC

300An event loop is described by a C<struct ev_loop *> (the C<struct> is 300An event loop is described by a C<struct ev_loop *> (the C<struct> is
301I<not> optional in this case unless libev 3 compatibility is disabled, as 301I<not> optional in this case unless libev 3 compatibility is disabled, as
302libev 3 had an C<ev_loop> function colliding with the struct name). 302libev 3 had an C<ev_loop> function colliding with the struct name).
303 303
304The library knows two types of such loops, the I<default> loop, which 304The library knows two types of such loops, the I<default> loop, which
305supports signals and child events, and dynamically created event loops 305supports child process events, and dynamically created event loops which
306which do not. 306do not.
307 307
308=over 4 308=over 4
309 309
310=item struct ev_loop *ev_default_loop (unsigned int flags) 310=item struct ev_loop *ev_default_loop (unsigned int flags)
311 311
341 341
342Example: Restrict libev to the select and poll backends, and do not allow 342Example: Restrict libev to the select and poll backends, and do not allow
343environment settings to be taken into account: 343environment settings to be taken into account:
344 344
345 ev_default_loop (EVBACKEND_POLL | EVBACKEND_SELECT | EVFLAG_NOENV); 345 ev_default_loop (EVBACKEND_POLL | EVBACKEND_SELECT | EVFLAG_NOENV);
346
347Example: Use whatever libev has to offer, but make sure that kqueue is
348used if available (warning, breaks stuff, best use only with your own
349private event loop and only if you know the OS supports your types of
350fds):
351
352 ev_default_loop (ev_recommended_backends () | EVBACKEND_KQUEUE);
353 346
354=item struct ev_loop *ev_loop_new (unsigned int flags) 347=item struct ev_loop *ev_loop_new (unsigned int flags)
355 348
356This will create and initialise a new event loop object. If the loop 349This will create and initialise a new event loop object. If the loop
357could not be initialised, returns false. 350could not be initialised, returns false.
589Example: Try to create a event loop that uses epoll and nothing else. 582Example: Try to create a event loop that uses epoll and nothing else.
590 583
591 struct ev_loop *epoller = ev_loop_new (EVBACKEND_EPOLL | EVFLAG_NOENV); 584 struct ev_loop *epoller = ev_loop_new (EVBACKEND_EPOLL | EVFLAG_NOENV);
592 if (!epoller) 585 if (!epoller)
593 fatal ("no epoll found here, maybe it hides under your chair"); 586 fatal ("no epoll found here, maybe it hides under your chair");
587
588Example: Use whatever libev has to offer, but make sure that kqueue is
589used if available.
590
591 struct ev_loop *loop = ev_loop_new (ev_recommended_backends () | EVBACKEND_KQUEUE);
594 592
595=item ev_loop_destroy (loop) 593=item ev_loop_destroy (loop)
596 594
597Destroys an event loop object (frees all memory and kernel state 595Destroys an event loop object (frees all memory and kernel state
598etc.). None of the active event watchers will be stopped in the normal 596etc.). None of the active event watchers will be stopped in the normal
1114=item C<EV_FORK> 1112=item C<EV_FORK>
1115 1113
1116The event loop has been resumed in the child process after fork (see 1114The event loop has been resumed in the child process after fork (see
1117C<ev_fork>). 1115C<ev_fork>).
1118 1116
1117=item C<EV_CLEANUP>
1118
1119The event loop is about to be destroyed (see C<ev_cleanup>).
1120
1119=item C<EV_ASYNC> 1121=item C<EV_ASYNC>
1120 1122
1121The given async watcher has been asynchronously notified (see C<ev_async>). 1123The given async watcher has been asynchronously notified (see C<ev_async>).
1122 1124
1123=item C<EV_CUSTOM> 1125=item C<EV_CUSTOM>
3092 3094
3093=head3 Watcher-Specific Functions and Data Members 3095=head3 Watcher-Specific Functions and Data Members
3094 3096
3095=over 4 3097=over 4
3096 3098
3097=item ev_fork_init (ev_signal *, callback) 3099=item ev_fork_init (ev_fork *, callback)
3098 3100
3099Initialises and configures the fork watcher - it has no parameters of any 3101Initialises and configures the fork watcher - it has no parameters of any
3100kind. There is a C<ev_fork_set> macro, but using it is utterly pointless, 3102kind. There is a C<ev_fork_set> macro, but using it is utterly pointless,
3101believe me. 3103really.
3102 3104
3103=back 3105=back
3106
3107
3108=head2 C<ev_cleanup> - even the best things end
3109
3110Cleanup watchers are called just before the event loop is being destroyed
3111by a call to C<ev_loop_destroy>.
3112
3113While there is no guarantee that the event loop gets destroyed, cleanup
3114watchers provide a convenient method to install cleanup hooks for your
3115program, worker threads and so on - you just to make sure to destroy the
3116loop when you want them to be invoked.
3117
3118Cleanup watchers are invoked in the same way as any other watcher. Unlike
3119all other watchers, they do not keep a reference to the event loop (which
3120makes a lot of sense if you think about it). Like all other watchers, you
3121can call libev functions in the callback, except C<ev_cleanup_start>.
3122
3123=head3 Watcher-Specific Functions and Data Members
3124
3125=over 4
3126
3127=item ev_cleanup_init (ev_cleanup *, callback)
3128
3129Initialises and configures the cleanup watcher - it has no parameters of
3130any kind. There is a C<ev_cleanup_set> macro, but using it is utterly
3131pointless, I assure you.
3132
3133=back
3134
3135Example: Register an atexit handler to destroy the default loop, so any
3136cleanup functions are called.
3137
3138 static void
3139 program_exits (void)
3140 {
3141 ev_loop_destroy (EV_DEFAULT_UC);
3142 }
3143
3144 ...
3145 atexit (program_exits);
3104 3146
3105 3147
3106=head2 C<ev_async> - how to wake up an event loop 3148=head2 C<ev_async> - how to wake up an event loop
3107 3149
3108In general, you cannot use an C<ev_run> from multiple threads or other 3150In general, you cannot use an C<ev_run> from multiple threads or other
4830=back 4872=back
4831 4873
4832 4874
4833=head1 PORTING FROM LIBEV 3.X TO 4.X 4875=head1 PORTING FROM LIBEV 3.X TO 4.X
4834 4876
4835The major version 4 introduced some minor incompatible changes to the API. 4877The major version 4 introduced some incompatible changes to the API.
4836 4878
4837At the moment, the C<ev.h> header file tries to implement superficial 4879At the moment, the C<ev.h> header file provides compatibility definitions
4838compatibility, so most programs should still compile. Those might be 4880for all changes, so most programs should still compile. The compatibility
4839removed in later versions of libev, so better update early than late. 4881layer might be removed in later versions of libev, so better update to the
4882new API early than late.
4840 4883
4841=over 4 4884=over 4
4842 4885
4886=item C<EV_COMPAT3> backwards compatibility mechanism
4887
4888The backward compatibility mechanism can be controlled by
4889C<EV_COMPAT3>. See L<PREPROCESSOR SYMBOLS/MACROS> in the L<EMBEDDING>
4890section.
4891
4843=item C<ev_default_destroy> and C<ev_default_fork> have been removed 4892=item C<ev_default_destroy> and C<ev_default_fork> have been removed
4844 4893
4845These calls can be replaced easily by their C<ev_loop_xxx> counterparts: 4894These calls can be replaced easily by their C<ev_loop_xxx> counterparts:
4846 4895
4847 ev_loop_destroy (EV_DEFAULT); 4896 ev_loop_destroy (EV_DEFAULT_UC);
4848 ev_loop_fork (EV_DEFAULT); 4897 ev_loop_fork (EV_DEFAULT);
4849 4898
4850=item function/symbol renames 4899=item function/symbol renames
4851 4900
4852A number of functions and symbols have been renamed: 4901A number of functions and symbols have been renamed:
4872ev_loop> anymore and C<EV_TIMER> now follows the same naming scheme 4921ev_loop> anymore and C<EV_TIMER> now follows the same naming scheme
4873as all other watcher types. Note that C<ev_loop_fork> is still called 4922as all other watcher types. Note that C<ev_loop_fork> is still called
4874C<ev_loop_fork> because it would otherwise clash with the C<ev_fork> 4923C<ev_loop_fork> because it would otherwise clash with the C<ev_fork>
4875typedef. 4924typedef.
4876 4925
4877=item C<EV_COMPAT3> backwards compatibility mechanism
4878
4879The backward compatibility mechanism can be controlled by
4880C<EV_COMPAT3>. See L<PREPROCESSOR SYMBOLS/MACROS> in the L<EMBEDDING>
4881section.
4882
4883=item C<EV_MINIMAL> mechanism replaced by C<EV_FEATURES> 4926=item C<EV_MINIMAL> mechanism replaced by C<EV_FEATURES>
4884 4927
4885The preprocessor symbol C<EV_MINIMAL> has been replaced by a different 4928The preprocessor symbol C<EV_MINIMAL> has been replaced by a different
4886mechanism, C<EV_FEATURES>. Programs using C<EV_MINIMAL> usually compile 4929mechanism, C<EV_FEATURES>. Programs using C<EV_MINIMAL> usually compile
4887and work, but the library code will of course be larger. 4930and work, but the library code will of course be larger.

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