Name
setxattr, lsetxattr, fsetxattr — set an extended
attribute value
Synopsis
int
setxattr( |
const char * |
path, |
| |
const char * |
name, |
| |
const void * |
value, |
| |
size_t |
size, |
| |
int |
flags); |
int
lsetxattr( |
const char * |
path, |
| |
const char * |
name, |
| |
const void * |
value, |
| |
size_t |
size, |
| |
int |
flags); |
int
fsetxattr( |
int |
filedes, |
| |
const char * |
name, |
| |
const void * |
value, |
| |
size_t |
size, |
| |
int |
flags); |
DESCRIPTION
Extended attributes are name:value pairs associated with
inodes (files, directories, symlinks, etc). They are
extensions to the normal attributes which are associated with
all inodes in the system (i.e. the stat(2) data). A complete
overview of extended attributes concepts can be found in
attr(5).
setxattr() sets the
value of the extended
attribute identified by name and associated with the
given path in the
filesystem. The size
of the value must be
specified.
lsetxattr() is identical to
setxattr(), except in the case
of a symbolic link, where the extended attribute is set on
the link itself, not the file that it refers to.
fsetxattr() is identical to
setxattr(), only the extended
attribute is set on the open file pointed to by filedes (as returned by
open(2)) in place of
path.
An extended attribute name is a simple null-terminated
string. The name
includes a namespace prefix; there may be several, disjoint
namespaces associated with an individual inode. The
value of an extended
attribute is a chunk of arbitrary textual or binary data of
specified length.
The flags
parameter can be used to refine the semantics of the
operation. XATTR_CREATE specifies a pure create, which fails
if the named attribute exists already. XATTR_REPLACE
specifies a pure replace operation, which fails if the named
attribute does not already exist. By default (no flags), the
extended attribute will be created if need be, or will simply
replace the value if the attribute exists.
RETURN VALUE
On success, zero is returned. On failure, −1 is
returned and errno is set
appropriately.
If XATTR_CREATE is specified, and the attribute exists
already, errno is set to EEXIST.
If XATTR_REPLACE is specified, and the attribute does not
exist, errno is set to
ENOATTR.
If there is insufficient space remaining to store the
extended attribute, errno is set
to either ENOSPC, or EDQUOT if quota enforcement was the
cause.
If extended attributes are not supported by the
filesystem, or are disabled, errno is set to ENOTSUP.
The errors documented for the stat(2) system call are
also applicable here.
CONFORMING TO
These system calls are Linux specific.
SEE ALSO
getfattr(1), setfattr(1), getxattr(2), listxattr(2), open(2), removexattr(2), stat(2), attr(5)
Extended attributes system calls manual pages
(C) Andreas Gruenbacher, February 2001
(C) Silicon Graphics Inc, September 2001
This is free documentation; you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of
the License, or (at your option) any later version.
The GNU General Public License's references to "object code"
and "executables" are to be interpreted as the output of any
document formatting or typesetting system, including
intermediate and printed output.
This manual is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public
License along with this manual; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111,
USA.
|
