sd-hwdb — Read-only access to the hardware description database
#include <systemd/sd-hwdb.h>
pkg-config --cflags --libs libsystemd 
sd-hwdb.h is part of
    libsystemd(3) and allows
    read-only access the systemd database of hardware properties. See
    hwdb(7) and
    systemd-hwdb(8) for more
    information about the database.
See sd_hwdb_new(3) and sd_hwdb_get(3) for information about the functions available.
Functions described here are available as a shared
  library, which can be compiled against and linked to with the
  libsystemd pkg-config(1)
  file.
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.