Joachim Nilsson
d9f8caf0e8
In 2f9cce9 the invalidate_watcher() function was introduced to stop
invalid timer/cron and signal watchers. This patch refactors that
change to instead call the stop method for cron/timer and attempt to
restart failing signal watchers.
The cron/timer and signal watchers are quite different from regular
I/O watchers in that their internal "fd" is hidden from and not under
the control of the user, so we should try to handle them better. For
the former two we cannot do much other than stop and call the user's
registered callback with UEV_ERROR, but for the latter we can at least
try to restart it.
Signed-off-by: Joachim Nilsson <troglobit@gmail.com>
libuEv | Simple event loop for Linux
NOTE: Incompatible failure mode changes in v2.0 compared to v1.x!
Introduction
libuEv is a simple event loop in the style of the more established libevent, libev and the venerable Xt(3) event loop. The u (micro) in the name refers to both the small feature set and the small size overhead impact of the library.
Failure mode changes introduced in v2.0 may affect users of v1.x, See the ChangeLog for the full details.
Example
The library documentation is available as a separate document.
#include <stdio.h>
#include <uev/uev.h>
static void cb(uev_t *w, void *arg, int events)
{
puts("Every other second");
}
int main(void)
{
uev_t timer;
uev_ctx_t ctx;
uev_init(&ctx);
/* Set up a timer watcher to call cb() every other second */
uev_timer_init(&ctx, &timer, cb, NULL, 0, 2 * 1000);
return uev_run(&ctx, 0);
}
Build & Install
libuEv use the GNU configure and build system. To try out the bundled
examples, use the --enable-examples switch to the configure script.
There is also a limited unit test suite that can be useful to learn how
the library works.
./configure
make -j5
make test
sudo make install-strip
sudo ldconfig
The resulting .so file is ~14 kiB.
Origin & References
libuEv originates from LibUEvent by Flemming Madsen, but with a rewritten and much cleaner API. It is now more similar to the famous libev by Mark Lehmann. Another library inspiring this project is picoev by Oku Kazuho.
libuEv is developed and maintained by Joachim Nilsson. It is built for and developed on GNU/Linux systems, patches to support *BSD and its kqueue interface are most welcome.