sd_bus_get_name_machine_id - Retrieve a bus client's machine identity
int sd_bus_get_name_machine_id(sd_bus *bus, const char *name, sd_id128_t *machine);
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.
On success, this function returns a non-negative integer. On failure, it returns a negative errno-style error code.
Returned errors may indicate the following problems:
An argument is invalid.
The bus cannot be resolved.
The bus was created in a different process.
Memory allocation failed.
These APIs are implemented as a shared library, which can be compiled and linked to with the libsystemd pkg-config(1) file.