if_indextoname (3p) - Linux Man Pages
if_indextoname: map a network interface index to its corresponding
PROLOGThis manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.
if_indextoname - map a network interface index to its corresponding name
The if_indextoname() function shall map an interface index to its corresponding name.
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.
The if_indextoname() function shall fail if:
The interface does not exist.
COPYRIGHTPortions 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, Copyright (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.opengroup.org/unix/online.html .