145 lines
4.5 KiB
Groff
145 lines
4.5 KiB
Groff
.\" Copyright (c) 1983, 1991, 1993
|
|
.\" The Regents of the University of California. All rights reserved.
|
|
.\"
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
.\" modification, are permitted provided that the following conditions
|
|
.\" are met:
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
.\" 3. All advertising materials mentioning features or use of this software
|
|
.\" must display the following acknowledgement:
|
|
.\" This product includes software developed by the University of
|
|
.\" California, Berkeley and its contributors.
|
|
.\" 4. Neither the name of the University nor the names of its contributors
|
|
.\" may be used to endorse or promote products derived from this software
|
|
.\" without specific prior written permission.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
.\" SUCH DAMAGE.
|
|
.\"
|
|
.\" From: @(#)rcmd.3 8.1 (Berkeley) 6/4/93
|
|
.\" $Id: if_indextoname.3,v 1.2 1999/07/03 13:58:31 kleink Exp $
|
|
.\"
|
|
.Dd May 21, 1998
|
|
.Dt IF_NAMETOINDEX 3
|
|
.Os KAME
|
|
.Sh NAME
|
|
.Nm if_nametoindex ,
|
|
.Nm if_indextoname ,
|
|
.Nm if_nameindex ,
|
|
.Nm if_freenameindex
|
|
.Nd convert interface index to name, and vice versa
|
|
.Sh LIBRARY
|
|
.Lb libc
|
|
.Sh SYNOPSIS
|
|
.Fd #include <net/if.h>
|
|
.Ft "unsigned int"
|
|
.Fn if_nametoindex "const char *ifname"
|
|
.Ft "char *"
|
|
.Fn if_indextoname "unsigned int ifindex" "char *ifname"
|
|
.Ft "struct if_nameindex *"
|
|
.Fn if_nameindex "void"
|
|
.Ft "void"
|
|
.Fn if_freenameindex "struct if_nameindex *ptr"
|
|
.Sh DESCRIPTION
|
|
The functions map interface index to readable interface name
|
|
.Po
|
|
such as
|
|
.Li ``lo0''
|
|
.Pc
|
|
, and vice versa.
|
|
.Pp
|
|
.Fn if_nametoindex
|
|
converts readable interface name to interface index
|
|
.Pp positive integer value .
|
|
If the specified interface does not exist, 0 will be returned.
|
|
.Pp
|
|
.Fn if_indextoname
|
|
converts interface index to readable interface name.
|
|
The
|
|
.Fa ifname
|
|
argument must point to a buffer of at least
|
|
.Dv IF_NAMESIZE
|
|
bytes into which the interface name corresponding to the specified index is
|
|
returned.
|
|
.Po
|
|
.Dv IF_NAMESIZE
|
|
is also defined in
|
|
.Li <net/if.h>
|
|
and its value includes a terminating null byte at the end of the
|
|
interface name.
|
|
.Pc
|
|
This pointer is also the return value of the function.
|
|
If there is no interface corresponding to the specified index,
|
|
.Dv NULL
|
|
is returned.
|
|
.Pp
|
|
.Fn if_nameindex
|
|
returns an array of
|
|
.Fa if_nameindex
|
|
structures.
|
|
.Fa if_nametoindex
|
|
is also defined in
|
|
.Li <net/if.h> ,
|
|
and is as follows:
|
|
.Bd -literal -offset
|
|
struct if_nameindex {
|
|
unsigned int if_index; /* 1, 2, ... */
|
|
char *if_name; /* null terminated name: "le0", ... */
|
|
};
|
|
.Ed
|
|
.Pp
|
|
The end of the array of structures is indicated by a structure with
|
|
an
|
|
.Fa if_index
|
|
of 0 and an
|
|
.Fa if_name
|
|
of
|
|
.Dv NULL .
|
|
The function returns a
|
|
.Dv NULL
|
|
pointer upon an error.
|
|
The memory used for this array of structures along with the interface
|
|
names pointed to by the
|
|
.Fa if_name
|
|
members is obtained dynamically.
|
|
This memory is freed by the
|
|
.Fn if_freenameindex
|
|
function.
|
|
.Pp
|
|
.Fn if_freenameindex
|
|
takes a pointer that was returned by
|
|
.Fn if_nameindex
|
|
as argument
|
|
.Pq Fa ptr ,
|
|
and it reclaims the region allocated.
|
|
.Sh DIAGNOSTICS
|
|
.Fn if_nametoindex
|
|
returns 0 on error, positive integer on success.
|
|
.Fn if_indextoname
|
|
and
|
|
.Fn if_nameindex
|
|
return
|
|
.Dv NULL
|
|
on errors.
|
|
.Sh SEE ALSO
|
|
R. Gilligan, S. Thomson, J. Bound, and W. Stevens,
|
|
``Basic Socket Interface Extensions for IPv6,'' RFC2553, March 1999.
|
|
.Sh HISTORY
|
|
The implementation first appeared in WIDE Hydrangea IPv6 protocol stack kit.
|
|
.Sh STANDARDS
|
|
These functions are defined in ``Basic Socket Interface Extensions for IPv6''
|
|
.Pq RFC2533 .
|