создайте новый объект hwdb и создайте или уничтожьте ссылки на него (Create a new hwdb object and create or destroy references to it)
Имя (Name)
sd_hwdb_new, sd_hwdb_ref, sd_hwdb_unref - Create a new hwdb
object and create or destroy references to it
Синопсис (Synopsis)
#include <systemd/sd-hwdb.h>
int sd_hwdb_new(sd_hwdb **hwdb);
sd_hwdb* sd_hwdb_ref(sd_hwdb *hwdb);
sd_hwdb* sd_hwdb_unref(sd_hwdb *hwdb);
Описание (Description)
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.
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.
Возвращаемое значение (Return value)
On success, sd_hwdb_new() returns a non-negative integer. On
failure, it returns a negative errno-style error code.
sd_hwdb_ref() always returns the argument.
sd_hwdb_unref() always returns NULL.
Errors
Returned errors may indicate the following problems:
-ENOENT
The binary hardware database file could not be located. See
systemd-hwdb(8) for more information.
-EINVAL
The located binary hardware database file is in an
incompatible format.
-ENOMEM
Memory allocation failed.
Примечание (Note)
These APIs are implemented as a shared library, which can be
compiled and linked to with the libsystemd pkg-config(1) file.
Смотри также (See also)
systemd(1), systemd-udevd.service(8), sd-hwdb(3), systemd-hwdb(3)
