Metadata

The normal Unix file system does not provide a way to store metadata for files, that is, auxiliary information that is stored in resource forks in other operating systems. This is information about the file itself, like the type of data it contains, the icon that should be used to represent the file in a file manager, and other miscellaneous information.

GNOME provides a simple way to store metadata for files in a consistent fashion. Each file can have an arbitrary number of key/value pairs associated to it. For example, a key of icon-filename may point to a data value that specifies the filename of the icon image to be used to represent that file in a file manager. A key of icon-position may point to a data value that specifies the coordinates in which an icon for that file resides in the desktop.

The GNOME metadata functions provide counterparts to common file system operations like copying, moving, renaming, and deleting files. These functions are used to notify the metadata database about changes in the file system structure.