EMBEDDING THE LIBEV CODE INTO YOUR OWN PROGRAMS Instead of building the libev library you cna 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 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 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_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; 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 liev/ subdirectory and includes them in the EV/EVAPI.h (public interface) and EV.xs (implementation) files. Only EV.xs file will be compiled.