systemd sd_hwdb_new 3 sd_hwdb_new sd_hwdb_ref sd_hwdb_unref Create a new hwdb object and create or destroy references to it #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 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_seek3, sd_hwdb_get3, and sd_hwdb_enumerate3 to access entries. 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. Returned errors may indicate the following problems: -ENOENT The binary hardware database file could not be located. See systemd-hwdb8 for more information. -EINVAL The located binary hardware database file is in an incompatible format. -ENOMEM Memory allocation failed. systemd1, systemd-udev.service8, sd-hwdb3, systemd-hwdb3