IF_INDEXTONAME(3)          POSIX Programmer's Manual         IF_INDEXTONAME(3)



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

NAME
       if_indextoname -- map a network interface index to its corresponding
       name

SYNOPSIS
       #include <net/if.h>

       char *if_indextoname(unsigned ifindex, char *ifname);

DESCRIPTION
       The if__indextoname() function shall map an interface index to its
       corresponding name.

       When this function is called, ifname shall point to a buffer of at
       least {IF_NAMESIZE} bytes. The function shall place in this buffer the
       name of the interface with index ifindex.

RETURN VALUE
       If ifindex is an interface index, then the function shall return the
       value supplied in ifname, which points to a buffer now containing the
       interface name. Otherwise, the function shall return a null pointer and
       set errno to indicate the error.

ERRORS
       The if__indextoname() function shall fail if:

       ENXIO  The interface does not exist.

       The following sections are informative.

EXAMPLES
       None.

APPLICATION USAGE
       None.

RATIONALE
       None.

FUTURE DIRECTIONS
       None.

SEE ALSO
       getsockopt(), if__freenameindex(), if__nameindex(), if__nametoindex(),
       setsockopt()

       The Base Definitions volume of POSIX.1-2017, <net_if.h>

COPYRIGHT
       Portions of this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1-2017, Standard for Information Technology --
       Portable Operating System Interface (POSIX), The Open Group Base
       Specifications Issue 7, 2018 Edition, Copyright (C) 2018 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.opengroup.org/unix/online.html .

       Any typographical or formatting errors that appear in this page are
       most likely to have been introduced during the conversion of the source
       files to man page format. To report such errors, see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .



IEEE/The Open Group                  2017                    IF_INDEXTONAME(3)
