Description

File attributes in GIO consist of a list of key-value pairs.

Keys are strings that contain a key namespace and a key name, separated by a colon, e.g. "namespace:keyname". Namespaces are included to sort key-value pairs by namespaces for relevance. Keys can be retrived using wildcards, e.g. "standard::*" will return all of the keys in the "standard" namespace.

Values are stored within the list in GFileAttributeValue structures. Values can store different types, listed in the enum GFileAttributeType. Upon creation of a GFileAttributeValue, the type will be set to G_FILE_ATTRIBUTE_TYPE_INVALID.

The list of possible attributes for a filesystem (pointed to by a GFile) is availible as a GFileAttributeInfoList. This list is queryable by key names as indicated earlier.

Classes that implement GFileIface will create a GFileAttributeInfoList and install default keys and values for their given file system, architecture, and other possible implementation details (e.g., on a UNIX system, a file attribute key will be registered for the user id for a given file).

Please note that these are not all of the possible namespaces. More namespaces can be added from GIO modules or by individual applications. For more information about writing GIO modules, see GIOModule.

Note that there are no predefined keys in the "xattr" and "xattr-sys" namespaces. Keys for the "xattr" namespace are constructed by stripping away the "user." prefix from the extended user attribute, and prepending "xattr::". Keys for the "xattr-sys" namespace are constructed by concatenating "xattr-sys::" with the extended attribute name. All extended attribute values are returned as hex-encoded strings in which bytes outside the ASCII range are encoded as hexadecimal escape sequences of the form \xnn.

Details

typedef enum {
  G_FILE_ATTRIBUTE_TYPE_INVALID = 0,
  G_FILE_ATTRIBUTE_TYPE_STRING,
  G_FILE_ATTRIBUTE_TYPE_BYTE_STRING, /* zero terminated string of non-zero bytes */
  G_FILE_ATTRIBUTE_TYPE_BOOLEAN,
  G_FILE_ATTRIBUTE_TYPE_UINT32,
  G_FILE_ATTRIBUTE_TYPE_INT32,
  G_FILE_ATTRIBUTE_TYPE_UINT64,
  G_FILE_ATTRIBUTE_TYPE_INT64,
  G_FILE_ATTRIBUTE_TYPE_OBJECT
} GFileAttributeType;

typedef enum {
  G_FILE_ATTRIBUTE_INFO_NONE            = 0,
  G_FILE_ATTRIBUTE_INFO_COPY_WITH_FILE  = (1 << 0),
  G_FILE_ATTRIBUTE_INFO_COPY_WHEN_MOVED = (1 << 1)
} GFileAttributeInfoFlags;

typedef enum {
  G_FILE_ATTRIBUTE_STATUS_UNSET = 0,
  G_FILE_ATTRIBUTE_STATUS_SET,
  G_FILE_ATTRIBUTE_STATUS_ERROR_SETTING
} GFileAttributeStatus;

typedef struct {
  char                    *name;
  GFileAttributeType       type;
  GFileAttributeInfoFlags  flags;
} GFileAttributeInfo;

typedef struct {
  GFileAttributeInfo *infos;
  int                 n_infos;
} GFileAttributeInfoList;

GFileAttributeInfoList * g_file_attribute_info_list_new (void);

GFileAttributeInfoList * g_file_attribute_info_list_ref (GFileAttributeInfoList *list);

void                g_file_attribute_info_list_unref    (GFileAttributeInfoList *list);

GFileAttributeInfoList * g_file_attribute_info_list_dup (GFileAttributeInfoList *list);

const GFileAttributeInfo * g_file_attribute_info_list_lookup
                                                        (GFileAttributeInfoList *list,
                                                         const char *name);

void                g_file_attribute_info_list_add      (GFileAttributeInfoList *list,
                                                         const char *name,
                                                         GFileAttributeType type,
                                                         GFileAttributeInfoFlags flags);

See Also