This function looks for a key file named file in the paths
specified in search_dirs, loads the file into key_file and
returns the file's full path in full_path.
If the file could not be found in any of the search_dirs,
G_KEY_FILE_ERROR_NOT_FOUND is returned. If
the file is found but the OS returns an error when opening or reading the
file, a G_FILE_ERROR is returned. If there is a problem parsing the file, a
G_KEY_FILE_ERROR is returned.
This function looks for a key file named file in the paths specified in search_dirs, loads the file into key_file and returns the file's full path in full_path.
If the file could not be found in any of the search_dirs, G_KEY_FILE_ERROR_NOT_FOUND is returned. If the file is found but the OS returns an error when opening or reading the file, a G_FILE_ERROR is returned. If there is a problem parsing the file, a G_KEY_FILE_ERROR is returned.