gio-GFileAttribute: GFileAttribute

Description

Key-Value Paired File Attributes

Arguments

Methods and Functions

gFileAttributeInfoListNew() gFileAttributeInfoListLookup(object, name) gFileAttributeInfoListAdd(object, name, type, flags = "G_FILE_ATTRIBUTE_INFO_NONE")

Hierarchy

GEnum
   +----GFileAttributeType
GFlags
   +----GFileAttributeInfoFlags
GEnum
   +----GFileAttributeStatus

Detailed 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).

"standard"

The "Standard" namespace. General file information that any application may need should be put in this namespace. Examples include the file's name, type, and size.

"etag"

The "Entity Tag" namespace. Currently, the only key in this namespace is "value", which contains the value of the current entity tag.

"id"

The "Identification" namespace. This namespace is used by file managers and applications that list directories to check for loops and to uniquely identify files.

"access"

The "Access" namespace. Used to check if a user has the proper privilidges to access files and perform file operations. Keys in this namespace are made to be generic and easily understood, e.g. the "can_read" key is TRUE if the current user has permission to read the file. UNIX permissions and NTFS ACLs in Windows should be mapped to these values.

"mountable"

The "Mountable" namespace. Includes simple boolean keys for checking if a file or path supports mount operations, e.g. mount, unmount, eject. These are used for files of type G_FILE_TYPE_MOUNTABLE .

"time"

The "Time" namespace. Includes file access, changed, created times.

"unix"

The "Unix" namespace. Includes UNIX-specific information and may not be available for all files. Examples include the UNIX "UID", "GID", etc.

"dos"

The "DOS" namespace. Includes DOS-specific information and may not be available for all files. Examples include "is_system" for checking if a file is marked as a system file, and "is_archive" for checking if a file is marked as an archive file.

"owner"

The "Owner" namespace. Includes information about who owns a file. May not be available for all file systems. Examples include "user" for getting the user name of the file owner. This information is often mapped from some backend specific data such as a unix UID.

"thumbnail"

The "Thumbnail" namespace. Includes information about file thumbnails and their location within the file system. Exaples of keys in this namespace include "path" to get the location of a thumbnail, and "failed" to check if thumbnailing of the file failed.

"filesystem"

The "Filesystem" namespace. Gets information about the file system where a file is located, such as its type, how much space is left available, and the overall size of the file system.

"gvfs"

The "GVFS" namespace. Keys in this namespace contain information about the current GVFS backend in use.

"xattr"

The "xattr" namespace. Gets information about extended user attributes. See attr(5). The "user." prefix of the extended user attribute name is stripped away when constructing keys in this namespace, e.g. "xattr::mime_type" for the extended attribute with the name "user.mime_type". Note that this information is only available if GLib has been built with extended attribute support.

"xattr-sys"

The "xattr-sys" namespace. Gets information about extended attributes which are not user-specific. See attr(5). Note that this information is only available if GLib has been built with extended attribute support.

"selinux"

The "SELinux" namespace. Includes information about the SELinux context of files. Note that this information is only available if GLib has been built with SELinux support.

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.

`G_FILE_ATTRIBUTE_STANDARD_TYPE`	standard::type
uint32 ( `GFileType` )	`G_FILE_ATTRIBUTE_STANDARD_IS_HIDDEN`
standard::is-hidden	boolean
`G_FILE_ATTRIBUTE_STANDARD_IS_BACKUP`	standard::is-backup
boolean	`G_FILE_ATTRIBUTE_STANDARD_IS_SYMLINK`
standard::is-symlink	boolean
`G_FILE_ATTRIBUTE_STANDARD_IS_VIRTUAL`	standard::is-virtual
boolean	`G_FILE_ATTRIBUTE_STANDARD_NAME`
standard::name	byte string
`G_FILE_ATTRIBUTE_STANDARD_DISPLAY_NAME`	standard::display-name
string	`G_FILE_ATTRIBUTE_STANDARD_EDIT_NAME`
standard::edit-name	string
`G_FILE_ATTRIBUTE_STANDARD_ICON`	standard::icon
object ( `GIcon` )	`G_FILE_ATTRIBUTE_STANDARD_CONTENT_TYPE`
standard::content-type	string
`G_FILE_ATTRIBUTE_STANDARD_FAST_CONTENT_TYPE`	standard::fast-content-type
string	`G_FILE_ATTRIBUTE_STANDARD_SIZE`
standard::size	uint64
`G_FILE_ATTRIBUTE_STANDARD_ALLOCATED_SIZE`	standard::allocated-size
uint64	`G_FILE_ATTRIBUTE_STANDARD_SYMLINK_TARGET`
standard::symlink-target	byte string
`G_FILE_ATTRIBUTE_STANDARD_TARGET_URI`	standard::target-uri
string	`G_FILE_ATTRIBUTE_STANDARD_SORT_ORDER`
standard::sort-order	int32
`G_FILE_ATTRIBUTE_ETAG_VALUE`	etag::value
string	`G_FILE_ATTRIBUTE_ID_FILE`
id::file	string
`G_FILE_ATTRIBUTE_ID_FILESYSTEM`	id::filesystem
string	`G_FILE_ATTRIBUTE_ACCESS_CAN_READ`
access::can-read	boolean
`G_FILE_ATTRIBUTE_ACCESS_CAN_WRITE`	access::can-write
boolean	`G_FILE_ATTRIBUTE_ACCESS_CAN_EXECUTE`
access::can-execute	boolean
`G_FILE_ATTRIBUTE_ACCESS_CAN_DELETE`	access::can-delete
boolean	`G_FILE_ATTRIBUTE_ACCESS_CAN_TRASH`
access::can-trash	boolean
`G_FILE_ATTRIBUTE_ACCESS_CAN_RENAME`	access::can-rename
boolean	`G_FILE_ATTRIBUTE_MOUNTABLE_CAN_MOUNT`
mountable::can-mount	boolean
`G_FILE_ATTRIBUTE_MOUNTABLE_CAN_UNMOUNT`	mountable::can-unmount
boolean	`G_FILE_ATTRIBUTE_MOUNTABLE_CAN_EJECT`
mountable::can-eject	boolean
`G_FILE_ATTRIBUTE_MOUNTABLE_UNIX_DEVICE`	mountable::unix-device
uint32	`G_FILE_ATTRIBUTE_MOUNTABLE_UNIX_DEVICE_FILE`
mountable::unix-device-file	string
`G_FILE_ATTRIBUTE_MOUNTABLE_HAL_UDI`	mountable::hal-udi
string	`G_FILE_ATTRIBUTE_TIME_MODIFIED`
time::modified	uint64
`G_FILE_ATTRIBUTE_TIME_MODIFIED_USEC`	time::modified-usec
uint32	`G_FILE_ATTRIBUTE_TIME_ACCESS`
time::access	uint64
`G_FILE_ATTRIBUTE_TIME_ACCESS_USEC`	time::access-usec
uint32	`G_FILE_ATTRIBUTE_TIME_CHANGED`
time::changed	uint64
`G_FILE_ATTRIBUTE_TIME_CHANGED_USEC`	time::changed-usec
uint32	`G_FILE_ATTRIBUTE_TIME_CREATED`
time::created	uint64
`G_FILE_ATTRIBUTE_TIME_CREATED_USEC`	time::created-usec
uint32	`G_FILE_ATTRIBUTE_UNIX_DEVICE`
unix::device	uint32
`G_FILE_ATTRIBUTE_UNIX_INODE`	unix::inode
uint64	`G_FILE_ATTRIBUTE_UNIX_MODE`
unix::mode	uint32
`G_FILE_ATTRIBUTE_UNIX_NLINK`	unix::nlink
uint32	`G_FILE_ATTRIBUTE_UNIX_UID`
unix::uid	uint32
`G_FILE_ATTRIBUTE_UNIX_GID`	unix::gid
uint32	`G_FILE_ATTRIBUTE_UNIX_RDEV`
unix::rdev	uint32
`G_FILE_ATTRIBUTE_UNIX_BLOCK_SIZE`	unix::block-size
uint32	`G_FILE_ATTRIBUTE_UNIX_BLOCKS`
unix::blocks	uint64
`G_FILE_ATTRIBUTE_UNIX_IS_MOUNTPOINT`	unix::is-mountpoint
boolean	`G_FILE_ATTRIBUTE_DOS_IS_ARCHIVE`
dos::is-archive	boolean
`G_FILE_ATTRIBUTE_DOS_IS_SYSTEM`	dos::is-system
boolean	`G_FILE_ATTRIBUTE_OWNER_USER`
owner::user	string
`G_FILE_ATTRIBUTE_OWNER_USER_REAL`	owner::user-real
string	`G_FILE_ATTRIBUTE_OWNER_GROUP`
owner::group	string
`G_FILE_ATTRIBUTE_THUMBNAIL_PATH`	thumbnail::path
bytestring	`G_FILE_ATTRIBUTE_THUMBNAILING_FAILED`
thumbnail::failed	boolean
`G_FILE_ATTRIBUTE_PREVIEW_ICON`	preview::icon
object ( `GIcon` )	`G_FILE_ATTRIBUTE_FILESYSTEM_SIZE`
filesystem::size	uint64
`G_FILE_ATTRIBUTE_FILESYSTEM_FREE`	filesystem::free
uint64	`G_FILE_ATTRIBUTE_FILESYSTEM_TYPE`
filesystem::type	string
`G_FILE_ATTRIBUTE_FILESYSTEM_READONLY`	filesystem::readonly
boolean	`G_FILE_ATTRIBUTE_GVFS_BACKEND`
gvfs::backend	string
`G_FILE_ATTRIBUTE_SELINUX_CONTEXT`	selinux::context
string	`G_FILE_ATTRIBUTE_STANDARD_TYPE`

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 \x\varnn.

Structures

GFileAttributeInfo

Information about a specific attribute. GFileAttributeInfo is a transparent-type.

name: [char] the name of the attribute.
type: [GFileAttributeType] the GFileAttributeType type of the attribute.
flags: [GFileAttributeInfoFlags] a set of GFileAttributeInfoFlags.

GFileAttributeInfoList

Acts as a lightweight registry for possible valid file attributes. The registry stores Key-Value pair formats as GFileAttributeInfos.

infos: [GFileAttributeInfo] a list of GFileAttributeInfos.
nInfos: [integer] the number of values in the list.

Enums and Flags

GFileAttributeType

The data types for file attributes.

invalid: indicates an invalid or uninitalized type.
string: a null terminated UTF8 string.
byte-string: a zero terminated string of non-zero bytes.
boolean: a boolean value.
uint32: an unsigned 4-byte/32-bit integer.
int32: a signed 4-byte/32-bit integer.
uint64: an unsigned 8-byte/64-bit integer.
int64: a signed 8-byte/64-bit integer.
object: a GObject.

GFileAttributeInfoFlags

Flags specifying the behaviour of an attribute.

none: no flags set.
copy-with-file: copy the attribute values when the file is copied.
copy-when-moved: copy the attribute values when the file is moved.

GFileAttributeStatus

Used by gFileSetAttributesFromInfo when setting file attributes.

unset: Attribute value is unset (empty).
set: Attribute value is set.
error-setting: Indicates an error in setting the value.

References

http://library.gnome.org/devel//gio/gio-GFileAttribute.html

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