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

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

SYNOPSIS
       #include <sys/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
       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 xattr(7).

       setxattr() sets the value of the extended attribute identified by name and associated with the given path in the filesystem.  The  size  argument  specifies  the
       size (in bytes) of value; a zero-length value is permitted.

       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 null-terminated string.  The name includes a namespace prefix; there may be several, disjoint namespaces associated with an indi‐
       vidual inode.  The value of an extended attribute is a chunk of arbitrary textual or binary data of specified length.

       By default (i.e., 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 flags:

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

       XATTR_REPLACE
              Perform a pure replace operation, which fails if the named attribute does not already exist.

RETURN VALUE
       On success, zero is returned.  On failure, -1 is returned and errno is set to indicate the error.

ERRORS
       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.

       ENODATA
              XATTR_REPLACE was specified, and the attribute does not exist.

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

       ENOTSUP
              The namespace prefix of name is not valid.

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

       EPERM  The file is marked immutable or append-only.  (See ioctl_iflags(2).)

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

       ERANGE The size of name or value exceeds a filesystem-specific limit.

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

CONFORMING TO
       These system calls are Linux-specific.

SEE ALSO
       getfattr(1), setfattr(1), getxattr(2), listxattr(2), open(2), removexattr(2), stat(2), symlink(7), xattr(7)

Linux                                                                          2021-03-22                                                                    SETXATTR(2)