borg/docs/usage/general/file-metadata.rst.inc

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Support for file metadata
~~~~~~~~~~~~~~~~~~~~~~~~~
Besides regular file and directory structures, Borg can preserve
* symlinks (stored as symlink, the symlink is not followed)
* special files:
* character and block device files (restored via mknod)
* FIFOs ("named pipes")
* special file *contents* can be backed up in ``--read-special`` mode.
By default the metadata to create them with mknod(2), mkfifo(2) etc. is stored.
* hardlinked regular files, devices, FIFOs (considering all items in the same archive)
* timestamps in nanosecond precision: mtime, atime, ctime
* other timestamps: birthtime (on platforms supporting it)
* permissions:
* IDs of owning user and owning group
* names of owning user and owning group (if the IDs can be resolved)
* Unix Mode/Permissions (u/g/o permissions, suid, sgid, sticky)
On some platforms additional features are supported:
.. Yes/No's are grouped by reason/mechanism/reference.
+-------------------------+----------+-----------+------------+
| Platform | ACLs | xattr | Flags |
| | [#acls]_ | [#xattr]_ | [#flags]_ |
+=========================+==========+===========+============+
| Linux | Yes | Yes | Yes [1]_ |
+-------------------------+----------+-----------+------------+
| Mac OS X | Yes | Yes | Yes (all) |
+-------------------------+----------+-----------+------------+
| FreeBSD | Yes | Yes | Yes (all) |
+-------------------------+----------+-----------+------------+
| OpenBSD | n/a | n/a | Yes (all) |
+-------------------------+----------+-----------+------------+
| NetBSD | n/a | No [2]_ | Yes (all) |
+-------------------------+----------+-----------+------------+
| Solaris and derivatives | No [3]_ | No [3]_ | n/a |
+-------------------------+----------+-----------+------------+
| Windows (cygwin) | No [4]_ | No | No |
+-------------------------+----------+-----------+------------+
Other Unix-like operating systems may work as well, but have not been tested at all.
Note that most of the platform-dependent features also depend on the file system.
For example, ntfs-3g on Linux isn't able to convey NTFS ACLs.
.. [1] Only "nodump", "immutable", "compressed" and "append" are supported.
Feature request :issue:`618` for more flags.
.. [2] Feature request :issue:`1332`
.. [3] Feature request :issue:`1337`
.. [4] Cygwin tries to map NTFS ACLs to permissions with varying degrees of success.
.. [#acls] The native access control list mechanism of the OS. This normally limits access to
non-native ACLs. For example, NTFS ACLs aren't completely accessible on Linux with ntfs-3g.
.. [#xattr] extended attributes; key-value pairs attached to a file, mainly used by the OS.
This includes resource forks on Mac OS X.
.. [#flags] aka *BSD flags*. The Linux set of flags [1]_ is portable across platforms.
The BSDs define additional flags.