… | |
… | |
77 | on event-based programming, nor will it introduce event-based programming |
77 | on event-based programming, nor will it introduce event-based programming |
78 | with libev. |
78 | with libev. |
79 | |
79 | |
80 | Familiarity with event based programming techniques in general is assumed |
80 | Familiarity with event based programming techniques in general is assumed |
81 | throughout this document. |
81 | throughout this document. |
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82 | |
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83 | =head1 WHAT TO READ WHEN IN A HURRY |
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84 | |
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85 | This manual tries to be very detailed, but unfortunately, this also makes |
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86 | it very long. If you just want to know the basics of libev, I suggest |
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87 | reading L<ANATOMY OF A WATCHER>, then the L<EXAMPLE PROGRAM> above and |
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88 | look up the missing functions in L<GLOBAL FUNCTIONS> and the C<ev_io> and |
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89 | C<ev_timer> sections in L<WATCHER TYPES>. |
82 | |
90 | |
83 | =head1 ABOUT LIBEV |
91 | =head1 ABOUT LIBEV |
84 | |
92 | |
85 | Libev is an event loop: you register interest in certain events (such as a |
93 | Libev is an event loop: you register interest in certain events (such as a |
86 | file descriptor being readable or a timeout occurring), and it will manage |
94 | file descriptor being readable or a timeout occurring), and it will manage |
… | |
… | |
4757 | structure (guaranteed by POSIX but not by ISO C for example), but it also |
4765 | structure (guaranteed by POSIX but not by ISO C for example), but it also |
4758 | assumes that the same (machine) code can be used to call any watcher |
4766 | assumes that the same (machine) code can be used to call any watcher |
4759 | callback: The watcher callbacks have different type signatures, but libev |
4767 | callback: The watcher callbacks have different type signatures, but libev |
4760 | calls them using an C<ev_watcher *> internally. |
4768 | calls them using an C<ev_watcher *> internally. |
4761 | |
4769 | |
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4770 | =item pointer accesses must be thread-atomic |
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4771 | |
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4772 | Accessing a pointer value must be atomic, it must both be readable and |
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4773 | writable in one piece - this is the case on all current architectures. |
|
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4774 | |
4762 | =item C<sig_atomic_t volatile> must be thread-atomic as well |
4775 | =item C<sig_atomic_t volatile> must be thread-atomic as well |
4763 | |
4776 | |
4764 | The type C<sig_atomic_t volatile> (or whatever is defined as |
4777 | The type C<sig_atomic_t volatile> (or whatever is defined as |
4765 | C<EV_ATOMIC_T>) must be atomic with respect to accesses from different |
4778 | C<EV_ATOMIC_T>) must be atomic with respect to accesses from different |
4766 | threads. This is not part of the specification for C<sig_atomic_t>, but is |
4779 | threads. This is not part of the specification for C<sig_atomic_t>, but is |
… | |
… | |
4872 | =back |
4885 | =back |
4873 | |
4886 | |
4874 | |
4887 | |
4875 | =head1 PORTING FROM LIBEV 3.X TO 4.X |
4888 | =head1 PORTING FROM LIBEV 3.X TO 4.X |
4876 | |
4889 | |
4877 | The major version 4 introduced some minor incompatible changes to the API. |
4890 | The major version 4 introduced some incompatible changes to the API. |
4878 | |
4891 | |
4879 | At the moment, the C<ev.h> header file tries to implement superficial |
4892 | At the moment, the C<ev.h> header file provides compatibility definitions |
4880 | compatibility, so most programs should still compile. Those might be |
4893 | for all changes, so most programs should still compile. The compatibility |
4881 | removed in later versions of libev, so better update early than late. |
4894 | layer might be removed in later versions of libev, so better update to the |
|
|
4895 | new API early than late. |
4882 | |
4896 | |
4883 | =over 4 |
4897 | =over 4 |
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4898 | |
|
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4899 | =item C<EV_COMPAT3> backwards compatibility mechanism |
|
|
4900 | |
|
|
4901 | The backward compatibility mechanism can be controlled by |
|
|
4902 | C<EV_COMPAT3>. See L<PREPROCESSOR SYMBOLS/MACROS> in the L<EMBEDDING> |
|
|
4903 | section. |
4884 | |
4904 | |
4885 | =item C<ev_default_destroy> and C<ev_default_fork> have been removed |
4905 | =item C<ev_default_destroy> and C<ev_default_fork> have been removed |
4886 | |
4906 | |
4887 | These calls can be replaced easily by their C<ev_loop_xxx> counterparts: |
4907 | These calls can be replaced easily by their C<ev_loop_xxx> counterparts: |
4888 | |
4908 | |
… | |
… | |
4914 | ev_loop> anymore and C<EV_TIMER> now follows the same naming scheme |
4934 | ev_loop> anymore and C<EV_TIMER> now follows the same naming scheme |
4915 | as all other watcher types. Note that C<ev_loop_fork> is still called |
4935 | as all other watcher types. Note that C<ev_loop_fork> is still called |
4916 | C<ev_loop_fork> because it would otherwise clash with the C<ev_fork> |
4936 | C<ev_loop_fork> because it would otherwise clash with the C<ev_fork> |
4917 | typedef. |
4937 | typedef. |
4918 | |
4938 | |
4919 | =item C<EV_COMPAT3> backwards compatibility mechanism |
|
|
4920 | |
|
|
4921 | The backward compatibility mechanism can be controlled by |
|
|
4922 | C<EV_COMPAT3>. See L<PREPROCESSOR SYMBOLS/MACROS> in the L<EMBEDDING> |
|
|
4923 | section. |
|
|
4924 | |
|
|
4925 | =item C<EV_MINIMAL> mechanism replaced by C<EV_FEATURES> |
4939 | =item C<EV_MINIMAL> mechanism replaced by C<EV_FEATURES> |
4926 | |
4940 | |
4927 | The preprocessor symbol C<EV_MINIMAL> has been replaced by a different |
4941 | The preprocessor symbol C<EV_MINIMAL> has been replaced by a different |
4928 | mechanism, C<EV_FEATURES>. Programs using C<EV_MINIMAL> usually compile |
4942 | mechanism, C<EV_FEATURES>. Programs using C<EV_MINIMAL> usually compile |
4929 | and work, but the library code will of course be larger. |
4943 | and work, but the library code will of course be larger. |
… | |
… | |
5003 | |
5017 | |
5004 | =back |
5018 | =back |
5005 | |
5019 | |
5006 | =head1 AUTHOR |
5020 | =head1 AUTHOR |
5007 | |
5021 | |
5008 | Marc Lehmann <libev@schmorp.de>, with repeated corrections by Mikael Magnusson. |
5022 | Marc Lehmann <libev@schmorp.de>, with repeated corrections by Mikael |
|
|
5023 | Magnusson and Emanuele Giaquinta. |
5009 | |
5024 | |