SD_ID128_GET_MACHINE(3) sd_id128_get_machine SD_ID128_GET_MACHINE(3)NAME
sd_id128_get_machine, sd_id128_get_boot - Retrieve 128-bit IDs
SYNOPSIS
#include <systemd/sd-id128.h>
int sd_id128_get_machine(sd_id128_t* ret);
int sd_id128_get_boot(sd_id128_t* ret);
DESCRIPTIONsd_id128_get_machine() returns the machine ID of the executing host.
This reads and parses the machine-id(5) file. This function caches the
machine ID internally to make retrieving the machine ID a cheap
operation.
sd_id128_get_boot() returns the boot ID of the executing kernel. This
reads and parses the /proc/sys/kernel/random/boot_id file exposed by
the kernel. It is randomly generated early at boot and is unique for
every running kernel instance. See random(4) for more information. This
function also internally caches the returned ID to make this call a
cheap operation.
Note that sd_id128_get_boot() always returns a UUID v4 compatible ID.
sd_id128_get_machine() will also return a UUID v4-compatible ID on new
installations but might not on older. It is possible to convert the
machine ID into a UUID v4-compatible one. For more information, see
machine-id(5).
For more information about the "sd_id128_t" type see sd-id128(3).
RETURN VALUE
The two calls return 0 on success (in which case ret is filled in), or
a negative errno-style error code.
NOTES
The sd_id128_get_machine() and sd_id128_get_boot() interfaces are
available as a shared library, which can be compiled and linked to with
the "libsystemd-id128" pkg-config(1) file.
SEE ALSOsystemd(1), sd-id128(3), machine-id(5), random(4),
sd_id128_randomize(3)systemd 208SD_ID128_GET_MACHINE(3)