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   sd_event_loop    ( 3 )

запустить цикл событий (Run an event loop)

Имя (Name)

sd_event_run, sd_event_loop - Run an event loop

Синопсис (Synopsis)

#include <systemd/sd-event.h>

int sd_event_run(sd_event *event, uint64_t usec);

int sd_event_loop(sd_event *event);


Описание (Description)

sd_event_run() may be used to run a single iteration of the event
       loop specified in the event parameter. The function waits until
       an event to process is available, and dispatches the registered
       handler for it. The usec parameter specifies the maximum time (in
       microseconds) to wait for an event. Use (uint64_t) -1 to specify
       an infinite timeout.

sd_event_loop() invokes sd_event_run() in a loop, thus implementing the actual event loop. The call returns as soon as exiting was requested using sd_event_exit(3).

The event loop object event is created with sd_event_new(3). Events sources to wait for and their handlers may be registered with sd_event_add_io(3), sd_event_add_time(3), sd_event_add_signal(3), sd_event_add_child(3), sd_event_add_defer(3), sd_event_add_post(3) and sd_event_add_exit(3).

For low-level control of event loop execution, use sd_event_prepare(3), sd_event_wait(3) and sd_event_dispatch(3) which are wrapped by sd_event_run(). Along with sd_event_get_fd(3), these functions allow integration of an sd-event(3) event loop into foreign event loop implementations.


Возвращаемое значение (Return value)

On failure, these functions return a negative errno-style error
       code.  sd_event_run() returns a positive, non-zero integer if an
       event source was dispatched, and zero when the specified timeout
       hit before an event source has seen any event, and hence no event
       source was dispatched.  sd_event_loop() returns the exit code
       specified when invoking sd_event_exit().

Errors Returned errors may indicate the following problems:

-EINVAL The event parameter is invalid or NULL.

-EBUSY The event loop object is not in the right state (see sd_event_prepare(3) for an explanation of possible states).

-ESTALE The event loop is already terminated.

-ECHILD The event loop has been created in a different process.

Other errors are possible, too.


Примечание (Note)

These APIs are implemented as a shared library, which can be
       compiled and linked to with the libsystemd pkg-config(1) file.

Смотри также (See also)

systemd(1), sd-event(3), sd_event_new(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_exit(3), sd_event_get_fd(3),
       sd_event_wait(3), GLib Main Event Loop[1]

Примечание (Note)

1. GLib Main Event Loop
           https://developer.gnome.org/glib/unstable/glib-The-Main-Event-Loop.html