sd_hwdb_new - Man Page

#include <systemd/sd-hwdb​.h>

int sd_hwdb_new(sd_hwdb **hwdb);

int sd_hwdb_new_from_path(const char *path, sd_hwdb **hwdb);

sd_hwdb* sd_hwdb_ref(sd_hwdb *hwdb);

sd_hwdb* sd_hwdb_unref(sd_hwdb *hwdb);

sd_hwdb_new() creates a new hwdb object to access the binary hwdb database​. Upon initialization, the file containing the binary representation of the hardware database is located and opened​. The new object is returned in hwdb​.

sd_hwdb_new_from_path() may be used to specify the path from which the binary hardware database should be opened​.

The hwdb object is reference counted​. sd_hwdb_ref() and sd_hwdb_unref() may be used to get a new reference or destroy an existing reference to an object​. The caller must dispose of the reference acquired with sd_hwdb_new() by calling sd_hwdb_unref() when done with the object​.

Use sd_hwdb_seek(3), sd_hwdb_get(3), and sd_hwdb_enumerate(3) to access entries​.

On success, sd_hwdb_new() and sd_hwdb_new_from_path() return a non-negative integer​. On failure, a negative errno-style error code is returned​.

sd_hwdb_ref() always returns the argument​.

sd_hwdb_unref() always returns NULL​.

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​.

sd_hwdb_new(), sd_hwdb_ref(), and sd_hwdb_unref() were added in version 246​.

sd_hwdb_new_from_path() was added in version 252​.

systemd(1), systemd-udevd.service(8), sd-hwdb(3), systemd-hwdb(8)