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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 sys-tem. system.
     tem.  They are stored as name:data pairs associated with file system objects (files, directories, sym-links, symlinks,
     links, 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 Compression 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 component 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