IF_NAMEINDEX(3P)                                    POSIX Programmer's Manual                                   IF_NAMEINDEX(3P)



PROLOG
       This  manual  page is part of the POSIX Programmer's Manual.  The Linux implementation of this interface may differ (con-
       sult the corresponding Linux manual page for details of Linux behavior), or the  interface  may  not  be  implemented  on
       Linux.

NAME
       if_nameindex - return all network interface names and indexes

SYNOPSIS
       #include <net/if.h>

       struct if_nameindex *if_nameindex(void);


DESCRIPTION
       The if_nameindex() function shall return an array of if_nameindex structures, one structure per interface. The end of the
       array is indicated by a structure with an if_index field of zero and an if_name field of NULL.

       Applications should call if_freenameindex() to release the memory that may be dynamically  allocated  by  this  function,
       after they have finished using it.

RETURN VALUE
       An array of structures identifying local interfaces. A NULL pointer is returned upon an error, with errno set to indicate
       the error.

ERRORS
       The if_nameindex() function may fail if:

       ENOBUFS
              Insufficient resources are available to complete the function.


       The following sections are informative.

EXAMPLES
       None.

APPLICATION USAGE
       None.

RATIONALE
       None.

FUTURE DIRECTIONS
       None.

SEE ALSO
       getsockopt(), if_freenameindex(), if_indextoname(),  if_nametoindex(),  setsockopt(),  the  Base  Definitions  volume  of
       IEEE Std 1003.1-2001, <net/if.h>

COPYRIGHT
       Portions  of  this  text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for
       Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6,  Copy-
       right (C) 2001-2003 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any
       discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open  Group
       Standard   is   the   referee   document.   The   original   Standard   can   be   obtained  online  at  http://www.open-
       group.org/unix/online.html .



IEEE/The Open Group                                           2003                                              IF_NAMEINDEX(3P)