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NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | VERSIONS | CONFORMING TO | SEE ALSO | COLOPHONThe Linux Programming Interface

SETXATTR(2)               Linux Programmer's Manual              SETXATTR(2)

NAME         top

       setxattr, lsetxattr, fsetxattr - set an extended attribute value

SYNOPSIS         top

       #include <sys/types.h>
       #include <attr/xattr.h>

       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 fd, const char *name,
                     const void *value, size_t size, int flags);

DESCRIPTION         top

       Extended attributes are name: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 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 file system.  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 referred to by fd (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 argument 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         top

       On success, zero is returned.  On failure, -1 is returned and errno
       is set appropriately.

ERRORS         top

       EDQUOT Disk quota limits meant that there is insufficient space
              remaining to store the extended attribute.

       EEXIST XATTR_CREATE was specified, and the attribute exists already.

       ENOATTR
              XATTR_REPLACE was specified, and the attribute does not exist.
              (ENOATTR is defined to be a synonym for ENODATA in
              <attr/xattr.h>.)

       ENOSPC There is insufficient space remaining to store the extended
              attribute.

       ENOTSUP
              Extended attributes are not supported by the file system, or
              are disabled, errno is set to ENOTSUP.

       In addition, the errors documented in stat(2) can also occur.

VERSIONS         top

       These system calls have been available on Linux since kernel 2.4;
       glibc support is provided since version 2.3.

CONFORMING TO         top

       These system calls are Linux-specific.

SEE ALSO         top

       getfattr(1), setfattr(1), getxattr(2), listxattr(2), open(2),
       removexattr(2), stat(2), attr(5), symlink(7)

COLOPHON         top

       This page is part of release 3.51 of the Linux man-pages project.  A
       description of the project, and information about reporting bugs, can
       be found at http://www.kernel.org/doc/man-pages/.

Linux                            2013-01-19                      SETXATTR(2)

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