extattr(3)

NAME

extattr_namespace_to_string, extattr_string_to_namespace

convert an
extended attribute namespace identifier to a string and vice

versa

LIBRARY

System Utilities Library (libutil, -lutil)

SYNOPSIS

#include <sys/extattr.h>
#include <libutil.h>
int
extattr_namespace_to_string(int     attrnamespace,      char
**string);
int
extattr_string_to_namespace(const    char    *string,    int
*attrnamespace);

DESCRIPTION

The extattr_namespace_to_string() function converts a VFS

extended
attribute identifier to a human-readable string; the
extattr_string_to_namespace() function undoes the aforemen

tioned operation, and converts a human-readable string representing a

namespace to a
namespace identifier. Although a file system may implement

arbitrary
namespaces, these functions only support the EXTATTR_NAMES

PACE_USER
(``user'') and EXTATTR_NAMESPACE_SYSTEM (``system'') names

paces, which
are defined in extattr(9).

These functions are meant to be used in error reporting and

other interactive tasks. For example, instead of printing the integer

identifying
an extended attribute in an error message, a program might

use
extattr_namespace_to_string() to obtain a human-readable

representation.
Likewise, instead of requiring a user to enter the integer

representing a
namespace, an interactive program might ask for a name and

use
extattr_string_to_namespace() to get the desired identifier.

RETURN VALUES

If any of the calls are unsuccessful, the value -1 is re

turned and the
global variable errno is set to indicate the error.

ERRORS

[EINVAL] The requested namespace could not be

identified.

SEE ALSO

extattr(2), getextattr(8), setextattr(8), extattr(9)

HISTORY

Extended attribute support was developed as part of the

TrustedBSD Project, and introduced in FreeBSD 5.0. It was developed to

support security extensions requiring additional labels to be associated

with each
file or directory.

BSD June 24, 2001

BSD