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Comparing libev/ev.pod (file contents):
Revision 1.326 by root, Sun Oct 24 19:44:27 2010 UTC vs.
Revision 1.333 by root, Mon Oct 25 09:31:47 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
… …
1114The 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
1115C<ev_fork>). 1115C<ev_fork>).
1116 1116
1117=item C<EV_CLEANUP> 1117=item C<EV_CLEANUP>
1118 1118
1119The event loop is abotu to be destroyed (see C<ev_cleanup>). 1119The event loop is about to be destroyed (see C<ev_cleanup>).
1120 1120
1121=item C<EV_ASYNC> 1121=item C<EV_ASYNC>
1122 1122
1123The given async watcher has been asynchronously notified (see C<ev_async>). 1123The given async watcher has been asynchronously notified (see C<ev_async>).
1124 1124
… …
3098 3098
3099=item ev_fork_init (ev_fork *, callback) 3099=item ev_fork_init (ev_fork *, callback)
3100 3100
3101Initialises and configures the fork watcher - it has no parameters of any 3101Initialises and configures the fork watcher - it has no parameters of any
3102kind. 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,
3103believe me. 3103really.
3104 3104
3105=back 3105=back
3106 3106
3107 3107
3108=head2 C<ev_cleanup> - even the best things end 3108=head2 C<ev_cleanup> - even the best things end
3109 3109
3110Cleanup watchers are called just before the event loop they are registered 3110Cleanup watchers are called just before the event loop is being destroyed
3111with is being destroyed. 3111by a call to C<ev_loop_destroy>.
3112 3112
3113While there is no guarantee that the event loop gets destroyed, cleanup 3113While there is no guarantee that the event loop gets destroyed, cleanup
3114watchers provide a convenient method to install cleanup hooks for your 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 3115program, worker threads and so on - you just to make sure to destroy the
3116loop when you want them to be invoked. 3116loop when you want them to be invoked.
3117 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
3118=head3 Watcher-Specific Functions and Data Members 3123=head3 Watcher-Specific Functions and Data Members
3119 3124
3120=over 4 3125=over 4
3121 3126
3122=item ev_cleanup_init (ev_cleanup *, callback) 3127=item ev_cleanup_init (ev_cleanup *, callback)
3123 3128
3124Initialises and configures the cleanup watcher - it has no parameters of 3129Initialises and configures the cleanup watcher - it has no parameters of
3125any kind. There is a C<ev_cleanup_set> macro, but using it is utterly 3130any kind. There is a C<ev_cleanup_set> macro, but using it is utterly
3126pointless, believe me. 3131pointless, I assure you.
3127 3132
3128=back 3133=back
3129 3134
3130Example: Register an atexit handler to destroy the default loop, so any 3135Example: Register an atexit handler to destroy the default loop, so any
3131cleanup functions are called. 3136cleanup functions are called.
… …
4752structure (guaranteed by POSIX but not by ISO C for example), but it also 4757structure (guaranteed by POSIX but not by ISO C for example), but it also
4753assumes that the same (machine) code can be used to call any watcher 4758assumes that the same (machine) code can be used to call any watcher
4754callback: The watcher callbacks have different type signatures, but libev 4759callback: The watcher callbacks have different type signatures, but libev
4755calls them using an C<ev_watcher *> internally. 4760calls them using an C<ev_watcher *> internally.
4756 4761
4762=item pointer accesses must be thread-atomic
4763
4764Accessing a pointer value must be atomic, it must both be readable and
4765writable in one piece - this is the case on all current architectures.
4766
4757=item C<sig_atomic_t volatile> must be thread-atomic as well 4767=item C<sig_atomic_t volatile> must be thread-atomic as well
4758 4768
4759The type C<sig_atomic_t volatile> (or whatever is defined as 4769The type C<sig_atomic_t volatile> (or whatever is defined as
4760C<EV_ATOMIC_T>) must be atomic with respect to accesses from different 4770C<EV_ATOMIC_T>) must be atomic with respect to accesses from different
4761threads. This is not part of the specification for C<sig_atomic_t>, but is 4771threads. This is not part of the specification for C<sig_atomic_t>, but is
… …
4867=back 4877=back
4868 4878
4869 4879
4870=head1 PORTING FROM LIBEV 3.X TO 4.X 4880=head1 PORTING FROM LIBEV 3.X TO 4.X
4871 4881
4872The major version 4 introduced some minor incompatible changes to the API. 4882The major version 4 introduced some incompatible changes to the API.
4873 4883
4874At the moment, the C<ev.h> header file tries to implement superficial 4884At the moment, the C<ev.h> header file provides compatibility definitions
4875compatibility, so most programs should still compile. Those might be 4885for all changes, so most programs should still compile. The compatibility
4876removed in later versions of libev, so better update early than late. 4886layer might be removed in later versions of libev, so better update to the
4887new API early than late.
4877 4888
4878=over 4 4889=over 4
4890
4891=item C<EV_COMPAT3> backwards compatibility mechanism
4892
4893The backward compatibility mechanism can be controlled by
4894C<EV_COMPAT3>. See L<PREPROCESSOR SYMBOLS/MACROS> in the L<EMBEDDING>
4895section.
4879 4896
4880=item C<ev_default_destroy> and C<ev_default_fork> have been removed 4897=item C<ev_default_destroy> and C<ev_default_fork> have been removed
4881 4898
4882These calls can be replaced easily by their C<ev_loop_xxx> counterparts: 4899These calls can be replaced easily by their C<ev_loop_xxx> counterparts:
4883 4900
… …
4909ev_loop> anymore and C<EV_TIMER> now follows the same naming scheme 4926ev_loop> anymore and C<EV_TIMER> now follows the same naming scheme
4910as all other watcher types. Note that C<ev_loop_fork> is still called 4927as all other watcher types. Note that C<ev_loop_fork> is still called
4911C<ev_loop_fork> because it would otherwise clash with the C<ev_fork> 4928C<ev_loop_fork> because it would otherwise clash with the C<ev_fork>
4912typedef. 4929typedef.
4913 4930
4914=item C<EV_COMPAT3> backwards compatibility mechanism
4915
4916The backward compatibility mechanism can be controlled by
4917C<EV_COMPAT3>. See L<PREPROCESSOR SYMBOLS/MACROS> in the L<EMBEDDING>
4918section.
4919
4920=item C<EV_MINIMAL> mechanism replaced by C<EV_FEATURES> 4931=item C<EV_MINIMAL> mechanism replaced by C<EV_FEATURES>
4921 4932
4922The preprocessor symbol C<EV_MINIMAL> has been replaced by a different 4933The preprocessor symbol C<EV_MINIMAL> has been replaced by a different
4923mechanism, C<EV_FEATURES>. Programs using C<EV_MINIMAL> usually compile 4934mechanism, C<EV_FEATURES>. Programs using C<EV_MINIMAL> usually compile
4924and work, but the library code will of course be larger. 4935and work, but the library code will of course be larger.
… …
4998 5009
4999=back 5010=back
5000 5011
5001=head1 AUTHOR 5012=head1 AUTHOR
5002 5013
5003Marc Lehmann <libev@schmorp.de>, with repeated corrections by Mikael Magnusson. 5014Marc Lehmann <libev@schmorp.de>, with repeated corrections by Mikael
5015Magnusson and Emanuele Giaquinta.
5004 5016

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