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 ALSOgetxattr(2), removexattr(2), setxattr(2)HISTORYlistxattr() and flistxattr() first appeared in Mac OS X 10.4.
Mac OS X Oct 19, 2004 Mac OS X
