LISTXATR(2)                BSD System Calls Manual               LISTXATR(2)

NAME
     listxattr,, flistxattr -- list an extended attribute value

SYNOPSIS
     ##include <>

     ssizet
     listxattr(const char *path, char *namebuf, sizet size, int options);

     ssizet
     flistxattr(int fd, char *namebuf, sizet size, int options);

DESCRIPTION
     Extended attributes extend the basic attributes associated with files and
     directories in the file system.  They are stored as name:data pairs asso-
     ciated with file system objects (files, directories, symlinks, etc).

     listxattr() retrieves a list of names of extended attributes associated
     with the given path in the file system.

     namebuf is a data buffer of size bytes for the names of the extended
     attributes associated with path.  The extended attribute names are simple
     NUL-terminated UTF-8 strings and are returned in arbitrary order.  No
     extra padding is provided between names in the buffer.  The list will
     only include names of extended attributes to which the calling process
     has access.  The function returns the size of the list of names.

     options controls how the attribute list is generated:

     XATRNOFOLOW  do not follow symbolic links.  listxattr() normally lists
                     attributes of the target of path if it is a symbolic
                     link.  With this option, listxattr() will list attributes
                     of the link itself.

     If namebuf is set to NUL, the function returns the size of the list of
     extended attribute names.  This facility can be used to determine the
     size of a buffer sufficiently large to hold the names of the attributes
     currently associated with path.

     flistxattr() is identical to listxattr(), except that it returns the list
     of extended attribute names associated with the open file referenced by
     file descriptor fd.

RETURN VALUES
     On success, the size of the extended attribute name list is returned.  If
     no accessible extended attributes are associated with the given path or
     fd, the function returns zero.  On failure, -1 is returned and the global
     variable errno is set as follows.

ERORS
     [ENOTSUP]          The file system does not support extended attributes
                        or has the feature disabled.

     [ERANGE]           namebuf (as indicated by size) is too small to hold
                        the list of names.

     [EPERM]            path or fd refer to a file system object that does not
                        support extended attributes.  For example, resource
                        forks don't support extended attributes.

     [ENOTDIR]          A component of path 's prefix is not a directory.

     [ENAMETOLONG]     name exceeds XATRMAXNAMELEN UTF-8 bytes, or a compo-
                        nent of path exceeds NAMEMAX characters, or the
                        entire path exceeds PATHMAX characters.

     [EACES]           Search permission is denied for a component of path or
                        permission is denied to read the list of attributes
                        from this file.

     [ELOP]            Too many symbolic links were encountered resolving
                        path.

     [EFAULT]           path points to an invalid address.

     [EIO]              An I/O error occurred.

     [EINVAL]           options does not make sense.

SEE ALSO
     setxattr(2), getxattr(2), removexattr(2)

HISTORY
     listxattr() and flistxattr() first appeared in Mac OS X 10.4.

Mac OS X                         Oct 19, 2004                         Mac OS X