libev/README.embed

EMBEDDING THE LIBEV CODE INTO YOUR OWN PROGRAMS

    Instead of building the libev library you can also include the code
    as-is into your programs. To update, you only have to copy a few files
    into your source tree.

    This is how it works:

FILESETS

    CORE EVENT LOOP

    To include only the libev core (all the ev_* functions):

        #define EV_STANDALONE   1
        #include "ev.c"

    This will automatically include ev.h, too, and should be done in a
    single C source file only to provide the function implementations. To
    use it, do the same for ev.h in all users:

        #define EV_STANDALONE   1
        #include "ev.h"

    You need the following files in your source tree, or in a directory
    in your include path (e.g. in libev/ when using -Ilibev):

        ev.h
        ev.c
        ev_vars.h
        ev_wrap.h
        ev_win32.c

        ev_select.c     only when select backend is enabled (which is by default)
        ev_poll.c       only when poll backend is enabled (disabled by default)
        ev_epoll.c      only when the epoll backend is enabled (disabled by default)
        ev_kqueue.c     only when the kqueue backend is enabled (disabled by default)

    "ev.c" includes the backend files directly when enabled.

    LIBEVENT COMPATIBILITY API

    To include the libevent compatibility API, also include:

        #include "event.c"

    in the file including "ev.c", and:

        #include "event.h"

    in the files that want to use the libevent API. This also includes "ev.h".

    You need the following additional files for this:

        event.h
        event.c

PREPROCESSOR SYMBOLS

    Libev can be configured via a variety of preprocessor symbols you have to define
    before including any of its files. The default is not to build for mulciplicity
    and only include the select backend.

    EV_STANDALONE

        Must always be "1", which keeps libev from including config.h or
        other files, and it also defines dummy implementations for some
        libevent functions (such as logging, which is not supported). It
        will also not define any of the structs usually found in "event.h"
        that are not directly supported by libev code alone.

    EV_USE_MONOTONIC

        If undefined or defined to be "1", libev will try to detect the
        availability of the monotonic clock option at both compiletime and
        runtime. Otherwise no use of the monotonic clock option will be
        attempted.

    EV_USE_REALTIME

        If defined to be "1", libev will try to detect the availability
        of the realtime clock option at compiletime (and assume its
        availability at runtime if successful). Otherwise no use of the
        realtime clock option will be attempted. This effectively replaces
        gettimeofday by clock_get (CLOCK_REALTIME, ...) and will not normally
        affect correctness.

    EV_USE_SELECT

       If undefined or defined to be "1", libev will compile in support
       for the select(2) backend. No attempt at autodetection will be
       done: if no other method takes over, select will be it. Otherwise
       the select backend will not be compiled in.

    EV_SELECT_USE_WIN32_HANDLES

       When defined to 1, the select backend will assume that select
       doesn't understand file descriptors but wants osf handles on
       win32 (this is the case when the select to be used is the winsock
       select). This means that it will call _get_osfhandle on the fd to
       convert it to an OS handle. Should not be defined on non-win32
       platforms.

    EV_USE_POLL

       If defined to be "1", libev will compile in support for the poll(2)
       backend. No attempt at autodetection will be done. poll usually
       performs worse than select, so its not enabled by default (it is
       also slightly less portable).

    EV_USE_EPOLL

       If defined to be "1", libev will compile in support for the Linux
       epoll backend. Its availability will be detected at runtime,
       otherwise another method will be used as fallback. This is the
       preferred backend for GNU/Linux systems.

    EV_USE_KQUEUE

       If defined to be "1", libev will compile in support for the BSD
       style kqueue backend. Its availability will be detected at runtime,
       otherwise another method will be used as fallback. This is the
       preferred backend for BSD and BSd-like systems. Darwin brokenness
       will be detected at runtime and routed around by disabling this
       backend.

    EV_COMMON
 
       By default, all watchers have a "void *data" member. By redefining
       this macro to a something else you can include more and other types
       of members. You have to define it each time you include one of the
       files, though, and it must be identical each time.

       For example, the perl EV module uses this:

           #define EV_COMMON                       \
             SV *self; /* contains this struct */  \
             SV *cb_sv, *fh /* note no trailing ";" */

    EV_PROTOTYPES

       If defined to be "0", then "ev.h" will not define any function
       prototypes, but still define all the structs and other
       symbols. This is occasionally useful.

    EV_MULTIPLICITY

       If undefined or defined to "1", then all event-loop-specific
       functions will have the "struct ev_loop *" as first argument, and
       you can create additional independent event loops. Otherwise there
       will be no support for multiple event loops and there is no first
       event loop pointer argument. Instead, all functions act on the
       single default loop.

EXAMPLES

    For a real-world example of a program the includes libev
    verbatim, you can have a look at the EV perl module
    (http://software.schmorp.de/pkg/EV.html).  It has the libev files in
    the libev/ subdirectory and includes them in the EV/EVAPI.h (public
    interface) and EV.xs (implementation) files. Only the EV.xs file will
    be compiled.

Revision:	1.8
Committed:	Thu Nov 8 17:56:30 2007 UTC (16 years, 6 months ago) by root
Branch:	MAIN
Changes since 1.7:	+1 -1 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.1	EMBEDDING THE LIBEV CODE INTO YOUR OWN PROGRAMS
2
3	root	1.8	Instead of building the libev library you can also include the code
4	root	1.1	as-is into your programs. To update, you only have to copy a few files
5			into your source tree.
6
7			This is how it works:
8
9			FILESETS
10
11	root	1.5	CORE EVENT LOOP
12
13	root	1.1	To include only the libev core (all the ev_* functions):
14
15			#define EV_STANDALONE 1
16			#include "ev.c"
17
18			This will automatically include ev.h, too, and should be done in a
19			single C source file only to provide the function implementations. To
20			use it, do the same for ev.h in all users:
21
22			#define EV_STANDALONE 1
23			#include "ev.h"
24
25			You need the following files in your source tree, or in a directory
26			in your include path (e.g. in libev/ when using -Ilibev):
27
28			ev.h
29			ev.c
30			ev_vars.h
31			ev_wrap.h
32	root	1.4	ev_win32.c
33
34	root	1.3	ev_select.c only when select backend is enabled (which is by default)
35			ev_poll.c only when poll backend is enabled (disabled by default)
36			ev_epoll.c only when the epoll backend is enabled (disabled by default)
37			ev_kqueue.c only when the kqueue backend is enabled (disabled by default)
38
39			"ev.c" includes the backend files directly when enabled.
40	root	1.1
41	root	1.5	LIBEVENT COMPATIBILITY API
42
43	root	1.1	To include the libevent compatibility API, also include:
44
45			#include "event.c"
46
47			in the file including "ev.c", and:
48
49			#include "event.h"
50
51			in the files that want to use the libevent API. This also includes "ev.h".
52
53			You need the following additional files for this:
54
55			event.h
56			event.c
57
58			PREPROCESSOR SYMBOLS
59
60			Libev can be configured via a variety of preprocessor symbols you have to define
61			before including any of its files. The default is not to build for mulciplicity
62			and only include the select backend.
63
64			EV_STANDALONE
65
66			Must always be "1", which keeps libev from including config.h or
67			other files, and it also defines dummy implementations for some
68			libevent functions (such as logging, which is not supported). It
69			will also not define any of the structs usually found in "event.h"
70			that are not directly supported by libev code alone.
71
72			EV_USE_MONOTONIC
73
74			If undefined or defined to be "1", libev will try to detect the
75			availability of the monotonic clock option at both compiletime and
76			runtime. Otherwise no use of the monotonic clock option will be
77			attempted.
78
79			EV_USE_REALTIME
80
81			If defined to be "1", libev will try to detect the availability
82			of the realtime clock option at compiletime (and assume its
83			availability at runtime if successful). Otherwise no use of the
84			realtime clock option will be attempted. This effectively replaces
85			gettimeofday by clock_get (CLOCK_REALTIME, ...) and will not normally
86			affect correctness.
87
88			EV_USE_SELECT
89
90			If undefined or defined to be "1", libev will compile in support
91			for the select(2) backend. No attempt at autodetection will be
92			done: if no other method takes over, select will be it. Otherwise
93			the select backend will not be compiled in.
94
95	root	1.7	EV_SELECT_USE_WIN32_HANDLES
96
97			When defined to 1, the select backend will assume that select
98			doesn't understand file descriptors but wants osf handles on
99			win32 (this is the case when the select to be used is the winsock
100			select). This means that it will call _get_osfhandle on the fd to
101			convert it to an OS handle. Should not be defined on non-win32
102			platforms.
103
104	root	1.1	EV_USE_POLL
105
106			If defined to be "1", libev will compile in support for the poll(2)
107			backend. No attempt at autodetection will be done. poll usually
108			performs worse than select, so its not enabled by default (it is
109			also slightly less portable).
110
111			EV_USE_EPOLL
112
113			If defined to be "1", libev will compile in support for the Linux
114			epoll backend. Its availability will be detected at runtime,
115			otherwise another method will be used as fallback. This is the
116			preferred backend for GNU/Linux systems.
117
118			EV_USE_KQUEUE
119
120			If defined to be "1", libev will compile in support for the BSD
121			style kqueue backend. Its availability will be detected at runtime,
122			otherwise another method will be used as fallback. This is the
123			preferred backend for BSD and BSd-like systems. Darwin brokenness
124			will be detected at runtime and routed around by disabling this
125			backend.
126
127			EV_COMMON
128
129			By default, all watchers have a "void *data" member. By redefining
130			this macro to a something else you can include more and other types
131			of members. You have to define it each time you include one of the
132			files, though, and it must be identical each time.
133
134			For example, the perl EV module uses this:
135
136			#define EV_COMMON \
137			SV self; / contains this struct */ \
138	root	1.6	SV cb_sv, fh /* note no trailing ";" */
139	root	1.1
140			EV_PROTOTYPES
141
142			If defined to be "0", then "ev.h" will not define any function
143			prototypes, but still define all the structs and other
144			symbols. This is occasionally useful.
145
146			EV_MULTIPLICITY
147
148			If undefined or defined to "1", then all event-loop-specific
149			functions will have the "struct ev_loop *" as first argument, and
150			you can create additional independent event loops. Otherwise there
151			will be no support for multiple event loops and there is no first
152			event loop pointer argument. Instead, all functions act on the
153			single default loop.
154
155			EXAMPLES
156
157	root	1.2	For a real-world example of a program the includes libev
158			verbatim, you can have a look at the EV perl module
159			(http://software.schmorp.de/pkg/EV.html). It has the libev files in
160	root	1.5	the libev/ subdirectory and includes them in the EV/EVAPI.h (public
161			interface) and EV.xs (implementation) files. Only the EV.xs file will
162			be compiled.
163	root	1.1