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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-15 19:41:09 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-15 19:41:09 +0000
commit0db324e2e5d9d3347ea0e93138372fb65aac09e6 (patch)
tree1b794022fb98db123c73021e75286a82c116aa7f /man7/xattr.7
parentReleasing progress-linux version 6.05.01-1~progress7.99u1. (diff)
downloadmanpages-0db324e2e5d9d3347ea0e93138372fb65aac09e6.tar.xz
manpages-0db324e2e5d9d3347ea0e93138372fb65aac09e6.zip
Merging upstream version 6.7.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--man7/xattr.730
1 files changed, 15 insertions, 15 deletions
diff --git a/man7/xattr.7 b/man7/xattr.7
index c2f12c9..c90aaf8 100644
--- a/man7/xattr.7
+++ b/man7/xattr.7
@@ -6,7 +6,7 @@
.\"
.\" SPDX-License-Identifier: GPL-2.0-or-later
.\"
-.TH xattr 7 2023-02-05 "Linux man-pages 6.05.01"
+.TH xattr 7 2023-10-31 "Linux man-pages 6.7"
.SH NAME
xattr \- Extended attributes
.SH DESCRIPTION
@@ -15,7 +15,7 @@ files and directories, similar to the environment strings associated
with a process.
An attribute may be defined or undefined.
If it is defined, its value may be empty or non-empty.
-.PP
+.P
Extended attributes are extensions to the normal attributes which are
associated with all inodes in the system (i.e., the
.BR stat (2)
@@ -23,11 +23,11 @@ data).
They are often used to provide additional functionality
to a filesystem\[em]for example, additional security features such as
Access Control Lists (ACLs) may be implemented using extended attributes.
-.PP
+.P
Users with search access to a file or directory may use
.BR listxattr (2)
to retrieve a list of attribute names defined for that file or directory.
-.PP
+.P
Extended attributes are accessed as atomic objects.
Reading
.RB ( getxattr (2))
@@ -35,7 +35,7 @@ retrieves the whole value of an attribute and stores it in a buffer.
Writing
.RB ( setxattr (2))
replaces any previous value with the new value.
-.PP
+.P
Space consumed for extended attributes may be counted towards the disk quotas
of the file owner and file group.
.SS Extended attribute namespaces
@@ -48,14 +48,14 @@ form, for example,
.IR system.posix_acl_access ,
or
.IR security.selinux .
-.PP
+.P
The namespace mechanism is used to define different classes of extended
attributes.
These different classes exist for several reasons;
for example, the permissions
and capabilities required for manipulating extended attributes of one
namespace may differ to another.
-.PP
+.P
Currently, the
.IR security ,
.IR system ,
@@ -97,7 +97,7 @@ The access permissions for user
attributes are defined by the file permission bits:
read permission is required to retrieve the attribute value,
and writer permission is required to change it.
-.PP
+.P
The file permission bits of regular files and directories are
interpreted differently from the file permission bits of special files
and symbolic links.
@@ -108,7 +108,7 @@ The file permissions of symbolic links are not used in access checks.
These differences would allow users to consume filesystem resources in
a way not controllable by disk quotas for group or world writable
special files and directories.
-.PP
+.P
For this reason,
user extended attributes are allowed only for regular files and directories,
and access to user extended attributes is restricted to the
@@ -125,26 +125,26 @@ The list of attribute names that
can be returned is also limited to 64\ kB
(see BUGS in
.BR listxattr (2)).
-.PP
+.P
Some filesystems, such as Reiserfs (and, historically, ext2 and ext3),
require the filesystem to be mounted with the
.B user_xattr
mount option in order for user extended attributes to be used.
-.PP
+.P
In the current ext2, ext3, and ext4 filesystem implementations,
the total bytes used by the names and values of all of a file's
extended attributes must fit in a single filesystem block (1024, 2048
or 4096 bytes, depending on the block size specified when the
filesystem was created).
-.PP
+.P
In the Btrfs, XFS, and Reiserfs filesystem implementations, there is no
practical limit on the number of extended attributes
associated with a file, and the algorithms used to store extended
attribute information on disk are scalable.
-.PP
+.P
In the JFS, XFS, and Reiserfs filesystem implementations,
the limit on bytes used in an EA value is the ceiling imposed by the VFS.
-.PP
+.P
In the Btrfs filesystem implementation,
the total bytes used for the name, value, and implementation overhead bytes
is limited to the filesystem
@@ -158,7 +158,7 @@ Since the filesystems on which extended attributes are stored might also
be used on architectures with a different byte order and machine word
size, care should be taken to store attribute values in an
architecture-independent format.
-.PP
+.P
This page was formerly named
.BR attr (5).
.\" .SH AUTHORS