SD-EVENT(3) | sd-event | SD-EVENT(3) |
sd-event - A generic event loop implementation
#include <systemd/sd-event.h>
pkg-config --cflags --libs libsystemd
sd-event.h provides a generic event loop implementation, based on Linux epoll(7).
See sd_event_new(3), sd_event_run(3), sd_event_add_io(3), sd_event_add_time(3), sd_event_add_signal(3), sd_event_add_child(3), sd_event_add_inotify(3), sd_event_add_defer(3), sd_event_source_unref(3), sd_event_source_set_priority(3), sd_event_source_set_enabled(3), sd_event_source_set_userdata(3), sd_event_source_get_event(3), sd_event_source_get_pending(3), sd_event_source_set_description(3), sd_event_source_set_prepare(3), sd_event_source_set_ratelimit(3), sd_event_wait(3), sd_event_get_fd(3), sd_event_set_watchdog(3), sd_event_exit(3), sd_event_now(3) for more information about the functions available.
The event loop design is targeted on running a separate instance of the event loop in each thread; it has no concept of distributing events from a single event loop instance onto multiple worker threads. Dispatching events is strictly ordered and subject to configurable priorities. In each event loop iteration a single event source is dispatched. Each time an event source is dispatched the kernel is polled for new events, before the next event source is dispatched. The event loop is designed to honor priorities and provide fairness within each priority. It is not designed to provide optimal throughput, as this contradicts these goals due the limitations of the underlying epoll(7) primitives.
The event loop implementation provides the following features:
These APIs are implemented as a shared library, which can be compiled and linked to with the libsystemd pkg-config(1) file.
systemd(1), sd_event_new(3), sd_event_run(3), sd_event_add_io(3), sd_event_add_time(3), sd_event_add_signal(3), sd_event_add_child(3), sd_event_add_inotify(3), sd_event_add_defer(3), sd_event_source_unref(3), sd_event_source_set_priority(3), sd_event_source_set_enabled(3), sd_event_source_set_userdata(3), sd_event_source_get_event(3), sd_event_source_get_pending(3), sd_event_source_set_description(3), sd_event_source_set_prepare(3), sd_event_source_set_ratelimit(3), sd_event_wait(3), sd_event_get_fd(3), sd_event_set_watchdog(3), sd_event_exit(3), sd_event_now(3), epoll(7), timerfd_create(2), signalfd(2), waitid(2)
systemd 252 |