LISTXATTR(2)                BSD System Calls Manual               LISTXATTR(2)

NAME
     listxattr, flistxattr -- list extended attribute names

SYNOPSIS
     #include <sys/xattr.h>

     ssize_t
     listxattr(const char *path, char *namebuf, size_t size, int options);

     ssize_t
     flistxattr(int fd, char *namebuf, size_t 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
     NULL-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:

     XATTR_NOFOLLOW  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.

     XATTR_SHOWCOMPRESSION
                     listxattr() and flistxattr() will list HFS Plus Compres-
                     sion extended attribute(s) (if present) for the file
                     referred to by path or fd.

     If namebuf is set to NULL, 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.

ERRORS
     [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.

     [ENAMETOOLONG]     name exceeds XATTR_MAXNAMELEN UTF-8 bytes, or a compo-
                        nent of path exceeds NAME_MAX characters, or the
                        entire path exceeds PATH_MAX characters.

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

     [ELOOP]            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
     getxattr(2), removexattr(2), setxattr(2)

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

Mac OS X                         Oct 19, 2004                         Mac OS X