контролировать излучение сигнала установления местного соединения на шинных соединениях (Control emission of local connection establishment signal on bus connections)
Имя (Name)
sd_bus_set_connected_signal, sd_bus_get_connected_signal -
Control emission of local connection establishment signal on bus
connections
Синопсис (Synopsis)
#include <systemd/sd-bus.h>
int sd_bus_set_connected_signal(sd_bus *bus, int b);
int sd_bus_get_connected_signal(sd_bus *bus);
Описание (Description)
sd_bus_set_connected_signal() may be used to control whether a
local, synthetic Connected() signal message shall be generated
and enqueued for dispatching when the connection is fully
established. If the b parameter is zero the message is not
generated (the default), otherwise it is generated.
sd_bus_get_connected_signal() may be used to query whether this
feature is enabled. It returns zero if not, positive otherwise.
The Connected() signal message is generated from the
"org.freedesktop.DBus.Local" service and interface, and
"/org/freedesktop/DBus/Local" object path. Use
sd_bus_match_signal_async(3) to match on this signal.
This message is particularly useful on slow transports where
connections take a long time to be established. This is
especially the case when sd_bus_set_watch_bind(3) is used. The
signal is generated when the sd_bus_is_ready(3) returns positive
for the first time.
The Connected() signal corresponds with the Disconnected() signal
that is synthesized locally when the connection is terminated.
The latter is generated unconditionally however, unlike the
former which needs to be enabled explicitly before it is
generated, with sd_bus_set_connected_signal().
Возвращаемое значение (Return value)
On success, these functions return 0 or a positive integer. On
failure, they return a negative errno-style error code.
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_bus_match_signal_async(3),
sd_bus_set_watch_bind(3), sd_bus_is_ready(3)
