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Comparing libev/ev.pod (file contents):
Revision 1.280 by sf-exg, Tue Feb 16 12:17:57 2010 UTC vs.
Revision 1.282 by root, Wed Mar 10 08:19:39 2010 UTC

… …
3617 libev.m4 3617 libev.m4
3618 3618
3619=head2 PREPROCESSOR SYMBOLS/MACROS 3619=head2 PREPROCESSOR SYMBOLS/MACROS
3620 3620
3621Libev can be configured via a variety of preprocessor symbols you have to 3621Libev can be configured via a variety of preprocessor symbols you have to
3622define before including any of its files. The default in the absence of 3622define before including (or compiling) any of its files. The default in
3623autoconf is documented for every option. 3623the absence of autoconf is documented for every option.
3624
3625Symbols marked with "(h)" do not change the ABI, and can have different
3626values when compiling libev vs. including F<ev.h>, so it is permissible
3627to redefine them before including F<ev.h> without breakign compatibility
3628to a compiled library. All other symbols change the ABI, which means all
3629users of libev and the libev code itself must be compiled with compatible
3630settings.
3624 3631
3625=over 4 3632=over 4
3626 3633
3627=item EV_STANDALONE 3634=item EV_STANDALONE (h)
3628 3635
3629Must always be C<1> if you do not use autoconf configuration, which 3636Must always be C<1> if you do not use autoconf configuration, which
3630keeps libev from including F<config.h>, and it also defines dummy 3637keeps libev from including F<config.h>, and it also defines dummy
3631implementations for some libevent functions (such as logging, which is not 3638implementations for some libevent functions (such as logging, which is not
3632supported). It will also not define any of the structs usually found in 3639supported). It will also not define any of the structs usually found in
… …
3782as well as for signal and thread safety in C<ev_async> watchers. 3789as well as for signal and thread safety in C<ev_async> watchers.
3783 3790
3784In the absence of this define, libev will use C<sig_atomic_t volatile> 3791In the absence of this define, libev will use C<sig_atomic_t volatile>
3785(from F<signal.h>), which is usually good enough on most platforms. 3792(from F<signal.h>), which is usually good enough on most platforms.
3786 3793
3787=item EV_H 3794=item EV_H (h)
3788 3795
3789The name of the F<ev.h> header file used to include it. The default if 3796The name of the F<ev.h> header file used to include it. The default if
3790undefined is C<"ev.h"> in F<event.h>, F<ev.c> and F<ev++.h>. This can be 3797undefined is C<"ev.h"> in F<event.h>, F<ev.c> and F<ev++.h>. This can be
3791used to virtually rename the F<ev.h> header file in case of conflicts. 3798used to virtually rename the F<ev.h> header file in case of conflicts.
3792 3799
3793=item EV_CONFIG_H 3800=item EV_CONFIG_H (h)
3794 3801
3795If C<EV_STANDALONE> isn't C<1>, this variable can be used to override 3802If C<EV_STANDALONE> isn't C<1>, this variable can be used to override
3796F<ev.c>'s idea of where to find the F<config.h> file, similarly to 3803F<ev.c>'s idea of where to find the F<config.h> file, similarly to
3797C<EV_H>, above. 3804C<EV_H>, above.
3798 3805
3799=item EV_EVENT_H 3806=item EV_EVENT_H (h)
3800 3807
3801Similarly to C<EV_H>, this macro can be used to override F<event.c>'s idea 3808Similarly to C<EV_H>, this macro can be used to override F<event.c>'s idea
3802of how the F<event.h> header can be found, the default is C<"event.h">. 3809of how the F<event.h> header can be found, the default is C<"event.h">.
3803 3810
3804=item EV_PROTOTYPES 3811=item EV_PROTOTYPES (h)
3805 3812
3806If defined to be C<0>, then F<ev.h> will not define any function 3813If defined to be C<0>, then F<ev.h> will not define any function
3807prototypes, but still define all the structs and other symbols. This is 3814prototypes, but still define all the structs and other symbols. This is
3808occasionally useful if you want to provide your own wrapper functions 3815occasionally useful if you want to provide your own wrapper functions
3809around libev functions. 3816around libev functions.
… …
3859=item EV_FORK_ENABLE 3866=item EV_FORK_ENABLE
3860 3867
3861If undefined or defined to be C<1>, then fork watchers are supported. If 3868If undefined or defined to be C<1>, then fork watchers are supported. If
3862defined to be C<0>, then they are not. 3869defined to be C<0>, then they are not.
3863 3870
3871=item EV_SIGNAL_ENABLE
3872
3873If undefined or defined to be C<1>, then signal watchers are supported. If
3874defined to be C<0>, then they are not.
3875
3864=item EV_ASYNC_ENABLE 3876=item EV_ASYNC_ENABLE
3865 3877
3866If undefined or defined to be C<1>, then async watchers are supported. If 3878If undefined or defined to be C<1>, then async watchers are supported. If
3867defined to be C<0>, then they are not. 3879defined to be C<0>, then they are not.
3880
3881=item EV_CHILD_ENABLE
3882
3883If undefined or defined to be C<1> (and C<_WIN32> is not defined), then
3884child watchers are supported. If defined to be C<0>, then they are not.
3868 3885
3869=item EV_MINIMAL 3886=item EV_MINIMAL
3870 3887
3871If you need to shave off some kilobytes of code at the expense of some 3888If you need to shave off some kilobytes of code at the expense of some
3872speed (but with the full API), define this symbol to C<1>. Currently this 3889speed (but with the full API), define this symbol to C<1>. Currently this
… …
3874on amd64. It also selects a much smaller 2-heap for timer management over 3891on amd64. It also selects a much smaller 2-heap for timer management over
3875the default 4-heap. 3892the default 4-heap.
3876 3893
3877You can save even more by disabling watcher types you do not need 3894You can save even more by disabling watcher types you do not need
3878and setting C<EV_MAXPRI> == C<EV_MINPRI>. Also, disabling C<assert> 3895and setting C<EV_MAXPRI> == C<EV_MINPRI>. Also, disabling C<assert>
3879(C<-DNDEBUG>) will usually reduce code size a lot. 3896(C<-DNDEBUG>) will usually reduce code size a lot. Disabling inotify,
3897eventfd and signalfd will further help, and disabling backends one doesn't
3898need (e.g. poll, epoll, kqueue, ports) will help further.
3880 3899
3881Defining C<EV_MINIMAL> to C<2> will additionally reduce the core API to 3900Defining C<EV_MINIMAL> to C<2> will additionally reduce the core API to
3882provide a bare-bones event library. See C<ev.h> for details on what parts 3901provide a bare-bones event library. See C<ev.h> for details on what parts
3883of the API are still available, and do not complain if this subset changes 3902of the API are still available, and do not complain if this subset changes
3884over time. 3903over time.
3904
3905This example set of settings reduces the compiled size of libev from 24Kb
3906to 8Kb on my GNU/Linux amd64 system (and leaves little in - there is also
3907an effect on the amount of memory used). With an intelligent-enough linker
3908further unused functions might be left out as well automatically.
3909
3910 // tuning and API changes
3911 #define EV_MINIMAL 2
3912 #define EV_MULTIPLICITY 0
3913 #define EV_MINPRI 0
3914 #define EV_MAXPRI 0
3915
3916 // OS-specific backends
3917 #define EV_USE_INOTIFY 0
3918 #define EV_USE_EVENTFD 0
3919 #define EV_USE_SIGNALFD 0
3920 #define EV_USE_REALTIME 0
3921 #define EV_USE_MONOTONIC 0
3922 #define EV_USE_CLOCK_SYSCALL 0
3923
3924 // disable all backends except select
3925 #define EV_USE_POLL 0
3926 #define EV_USE_PORT 0
3927 #define EV_USE_KQUEUE 0
3928 #define EV_USE_EPOLL 0
3929
3930 // disable all watcher types that cna be disabled
3931 #define EV_STAT_ENABLE 0
3932 #define EV_PERIODIC_ENABLE 0
3933 #define EV_IDLE_ENABLE 0
3934 #define EV_FORK_ENABLE 0
3935 #define EV_SIGNAL_ENABLE 0
3936 #define EV_CHILD_ENABLE 0
3937 #define EV_ASYNC_ENABLE 0
3938 #define EV_EMBED_ENABLE 0
3939
3940=item EV_AVOID_STDIO
3941
3942If this is set to C<1> at compiletime, then libev will avoid using stdio
3943functions (printf, scanf, perror etc.). This will increase the codesize
3944somewhat, but if your program doesn't otherwise depend on stdio and your
3945libc allows it, this avoids linking in the stdio library which is quite
3946big.
3947
3948Note that error messages might become less precise when this option is
3949enabled.
3885 3950
3886=item EV_NSIG 3951=item EV_NSIG
3887 3952
3888The highest supported signal number, +1 (or, the number of 3953The highest supported signal number, +1 (or, the number of
3889signals): Normally, libev tries to deduce the maximum number of signals 3954signals): Normally, libev tries to deduce the maximum number of signals

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