.\" Copyright (C) Andreas Gruenbacher, February 2001

.\" Copyright (C) Silicon Graphics Inc, September 2001

.\"

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.\"

.TH SETXATTR 2 2017-03-13 "Linux" "Linux Programmer's Manual"

.SH NAME

setxattr, lsetxattr, fsetxattr \- set an extended attribute value

.SH SYNOPSIS

.fam C

.nf

.B #include <sys/types.h>

.B #include <sys/xattr.h>

.PP

.BI "int setxattr(const char\ *" path ", const char\ *" name ,

.BI "              const void\ *" value ", size_t " size ", int " flags );

.BI "int lsetxattr(const char\ *" path ", const char\ *" name ,

.BI "              const void\ *" value ", size_t " size ", int " flags );

.BI "int fsetxattr(int " fd ", const char\ *" name ,

.BI "              const void\ *" value ", size_t " size ", int " flags );

.fi

.fam T

.SH DESCRIPTION

Extended attributes are

.IR name :\c

.I value

pairs associated with inodes (files, directories, symbolic links, etc.).

They are extensions to the normal attributes which are associated

with all inodes in the system (i.e., the

.BR stat (2)

data).

A complete overview of extended attributes concepts can be found in

.BR xattr (7).

.PP

.BR setxattr ()

sets the

.I value

of the extended attribute identified by

.I name

and associated with the given

.I path

in the filesystem.

The

.I size

argument specifies the size (in bytes) of

.IR value ;

a zero-length value is permitted.

.PP

.BR lsetxattr ()

is identical to

.BR 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.

.PP

.BR fsetxattr ()

is identical to

.BR setxattr (),

only the extended attribute is set on the open file referred to by

.I fd

(as returned by

.BR open (2))

in place of

.IR path .

.PP

An extended attribute name is a null-terminated string.

The

.I name

includes a namespace prefix; there may be several, disjoint

namespaces associated with an individual inode.

The

.I value

of an extended attribute is a chunk of arbitrary textual or

binary data of specified length.

.PP

By default

(i.e.,

.IR flags

is zero),

the extended attribute will be created if it does not exist,

or the value will be replaced if the attribute already exists.

To modify these semantics, one of the following values can be specified in

.IR flags :

.TP

.B XATTR_CREATE

Perform a pure create, which fails if the named attribute exists already.

.TP

.B XATTR_REPLACE

Perform a pure replace operation,

which fails if the named attribute does not already exist.

.SH RETURN VALUE

On success, zero is returned.

On failure, \-1 is returned and

.I errno

is set appropriately.

.SH ERRORS

.TP

.B EDQUOT

Disk quota limits meant that

there is insufficient space remaining to store the extended attribute.

.TP

.B EEXIST

.B XATTR_CREATE

was specified, and the attribute exists already.

.TP

.B ENOATTR

.B XATTR_REPLACE

was specified, and the attribute does not exist.

.RB ( ENOATTR

is defined to be a synonym for

.BR ENODATA

in

.IR <attr/xattr.h> .)

.TP

.B ENOSPC

There is insufficient space remaining to store the extended attribute.

.TP

.B ENOTSUP

The namespace prefix of

.I name

is not valid.

.TP

.B ENOTSUP

Extended attributes are not supported by the filesystem, or are disabled,

.TP

.B EPERM

The file is marked immutable or append-only.

(See

.BR ioctl_iflags (2).)

.PP

In addition, the errors documented in

.BR stat (2)

can also occur.

.SH VERSIONS

These system calls have been available on Linux since kernel 2.4;

glibc support is provided since version 2.3.

.SH CONFORMING TO

These system calls are Linux-specific.

.\" .SH AUTHORS

.\" Andreas Gruenbacher,

.\" .RI < a.gruenbacher@computer.org >

.\" and the SGI XFS development team,

.\" .RI < linux-xfs@oss.sgi.com >.

.\" Please send any bug reports or comments to these addresses.

.SH SEE ALSO

.BR getfattr (1),

.BR setfattr (1),

.BR getxattr (2),

.BR listxattr (2),

.BR open (2),

.BR removexattr (2),

.BR stat (2),

.BR symlink (7),

.BR xattr (7)

.SH COLOPHON

This page is part of release 4.15 of the Linux

.I man-pages

project.

A description of the project,

information about reporting bugs,

and the latest version of this page,

can be found at

\%https://www.kernel.org/doc/man\-pages/.