sd_bus_get_name_machine_id - Man Page
Retrieve a bus client's machine identity
Synopsis
#include <systemd/sd-bus.h>
int sd_bus_get_name_machine_id(sd_bus *bus, const char *name, sd_id128_t *machine);
Description
sd_bus_get_name_machine_id() retrieves the D-Bus machine identity of the machine that the bus client identified by name is running on. Internally, it calls the GetMachineId method of the org.freedesktop.DBus.Peer interface. The D-Bus machine identity is a 128-bit UUID. On Linux systems running systemd, this corresponds to the contents of /etc/machine-id. On success, the machine identity is stored in machine.
Return Value
On success, this function returns a non-negative integer. On failure, it returns a negative errno-style error code.
Errors
Returned errors may indicate the following problems:
- -EINVAL
An argument is invalid.
- -ENOPKG
The bus cannot be resolved.
- -ECHILD
The bus was created in a different process, library or module instance.
- -ENOMEM
Memory allocation failed.
Notes
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.
History
sd_bus_get_name_machine_id() was added in version 221.