sd_bus_set_server - Man Page

#include <systemd/sd-bus​.h>

int sd_bus_set_server(sd_bus *bus, int b, sd_id128_t id);

int sd_bus_is_server(sd_bus *bus);

int sd_bus_get_bus_id(sd_bus *bus, sd_id128_t *id);

int sd_bus_set_bus_client(sd_bus *bus, int b);

int sd_bus_is_bus_client(sd_bus *bus);

int sd_bus_set_monitor(sd_bus *bus, int b);

int sd_bus_is_monitor(sd_bus *bus);

sd_bus_set_server() configures the bus object as a server for direct D-Bus connections​. b enables/disables the server mode​. If zero, the server mode is disabled​. Otherwise, the server mode is enabled​. Configuring a bus object as a server is required to allow establishing direct connections between two peers without going via the D-Bus daemon​. id must contain a 128-bit integer id for the server​. If clients add a guid field to their D-Bus address string, the server id must match this guid or the D-Bus authentication handshake will fail​. If no specific id is defined for the server, sd_id128_randomize(3) can be used to generate a random id instead​.

sd_bus_is_server() returns whether the server mode is enabled for the given bus object​.

sd_bus_get_bus_id() stores the D-Bus server id configured using sd_bus_set_server() (for server bus objects) or received during D-Bus authentication (for client bus objects) in id​.

sd_bus_set_bus_client() configures the bus object as a D-Bus daemon client​. b enables/disables the client mode​. If zero, the client mode is disabled and the bus object should connect directly to a D-Bus server​. Otherwise, the client mode is enabled and the bus object should connect to a D-Bus daemon​. When connecting to an existing bus using any of the functions in the sd_bus_open(3) family of functions or any of the functions in the sd_bus_default(3) family of functions, the bus object is automatically configured as a bus client​. However, when connecting to a D-Bus daemon by calling sd_bus_set_address(3) followed by sd_bus_start(3), the bus object should be manually configured as a bus client using sd_bus_set_bus_client()​. By default, a bus object is not configured as a D-Bus daemon client​.

sd_bus_is_bus_client() returns whether the client mode is enabled/disabled for the given bus object​.

sd_bus_set_monitor() configures the bus object as a D-Bus monitor object​. b enables/disables the monitor mode​. If zero, the monitor mode is disabled​. If non-zero, the monitor mode is enabled​. When the monitor mode is enabled, no messages may be sent via the bus object and it may not expose any objects on the bus​. To start monitoring messages, call the org​.freedesktop​.DBus​.Monitoring​.BecomeMonitor method of the D-Bus daemon and pass a list of matches indicating which messages to intercept​. See The D-Bus specification​^[1] for more information​.

sd_bus_is_monitor() returns whether the monitor mode is enabled/disabled for the given bus object​.

On success, sd_bus_set_server(), sd_bus_get_bus_id(), sd_bus_set_bus_client() and sd_bus_set_monitor() return a non-negative integer​. On failure, they return a negative errno-style error code​.

sd_bus_is_server(), sd_bus_is_bus_client() and sd_bus_is_monitor() return a positive integer when the server or client mode is enabled, respectively​. Otherwise, they return zero​.

Functions described here are available as a shared library, which can be compiled against and linked to with the libsystemd ​pkg-config(1) file​.

All functions listed here are thread-agnostic and only a single thread may operate on a given object at any given time​. Different threads may access the same object at different times​. Multiple independent objects may be used from different threads in parallel​.

The code described here uses getenv(3), which is declared to be not multi-thread-safe​. This means that the code calling the functions described here must not call setenv(3) from a parallel thread​. It is recommended to only do calls to setenv() from an early phase of the program when no other threads have been started​.

sd_bus_set_server(), sd_bus_is_server(), sd_bus_get_bus_id(), sd_bus_set_bus_client(), sd_bus_is_bus_client(), sd_bus_set_monitor(), and sd_bus_is_monitor() were added in version 246​.

systemd(1), sd-bus(3)

1.

The D-Bus specification
https://dbus.freedesktop.org/doc/dbus-specification.html#bus-messages-become-monitor