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   sd_bus_get_event    ( 3 )

присоедините объект подключения к шине к циклу событий (Attach a bus connection object to an event loop)

Имя (Name)

sd_bus_attach_event, sd_bus_detach_event, sd_bus_get_event -
       Attach a bus connection object to an event loop

Синопсис (Synopsis)

#include <systemd/sd-bus.h>

int sd_bus_attach_event(sd_bus *bus, sd_event *e, int priority);

int sd_bus_detach_event(sd_bus *bus);

sd_event *sd_bus_get_event(sd_bus *bus);


Описание (Description)

sd_bus_attach_event() attaches the specified bus connection
       object to an sd-event(3) event loop object at the specified
       priority (see sd_event_source_set_priority(3) for details on
       event loop priorities). When a bus connection object is attached
       to an event loop incoming messages will be automatically read and
       processed, and outgoing messages written, whenever the event loop
       is run. When the event loop is about to terminate, the bus
       connection is automatically flushed and closed (see
       sd_bus_set_close_on_exit(3) for details on this). By default bus
       connection objects are not attached to any event loop. When a bus
       connection object is attached to one it is not necessary to
       invoke sd_bus_wait(3) or sd_bus_process(3) as this functionality
       is handled automatically by the event loop.

sd_bus_detach_event() detaches a bus object from its event loop.

The sd_bus_get_event() returns the event loop object the specified bus object is currently attached to, or NULL if it is currently not attached to any.

Note that sd_bus_attach_event() is only one of three supported ways to implement I/O event handling for bus connections. Alternatively use sd_bus_get_fd(3) for hooking up a bus connection object with external or manual event loops. Or use sd_bus_wait(3) as a simple synchronous, blocking I/O waiting call.


Возвращаемое значение (Return value)

On success, sd_bus_attach_event() and sd_bus_detach_event()
       return 0 or a positive integer. On failure, they return a
       negative errno-style error code.

sd_bus_get_event() returns an event loop object or NULL.

Errors Returned errors may indicate the following problems:

-ECHILD The bus connection has been created in a different process.


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-bus(3), sd-event(3),
       sd_event_source_set_priority(3), sd_bus_set_close_on_exit(3),
       sd_bus_wait(3), sd_bus_get_fd(3)