if_nametoindex(3) Library Functions Manual if_nametoindex(3)NAME
if_nametoindex - Maps an interface name to an interface index
LIBRARY
Standard C Library (libc.so, libc.a)
SYNOPSIS
#include <net/if.h>
unsigned int if_nametoindex ( const char *ifname) ;
PARAMETERS
Points to a buffer that contains the interface name.
DESCRIPTION
The if_indextoname() function maps an interface name to its corresponding interface index number.
RETURN VALUES
Upon successful conversion, the if_nametoindex() function returns an interface index number. If the interface does not exist, it returns
zero (0).
RELATED INFORMATION
Functions: if_freenameindex(3), if_indextoname(3), if_nameindex(3). delim off
if_nametoindex(3)
Check Out this Related Man Page
IF_NAMETOINDEX(3) Linux Programmer's Manual IF_NAMETOINDEX(3)NAME
if_nametoindex, if_indextoname - mappings between network interface names and indexes
SYNOPSIS
#include <net/if.h>
unsigned int if_nametoindex(const char *ifname);
char *if_indextoname(unsigned int ifindex, char *ifname);
DESCRIPTION
The if_nametoindex() function returns the index of the network interface corresponding to the name ifname.
The if_indextoname() function returns the name of the network interface corresponding to the interface index ifindex. The name is placed
in the buffer pointed to by ifname. The buffer must allow for the storage of at least IF_NAMESIZE bytes.
RETURN VALUE
On success, if_nametoindex() returns the index number of the network interface; on error, 0 is returned and errno is set appropriately.
On success, if_indextoname() returns ifname; on error, NULL is returned and errno is set appropriately.
ERRORS
if_nametoindex() may fail and set errno if:
ENODEV No interface found with given name.
if_indextoname() may fail and set errno if:
ENXIO No interface found for the index.
if_nametoindex() and if_indextoname() may also fail for any of the errors specified for socket(2) or ioctl(2).
ATTRIBUTES
For an explanation of the terms used in this section, see attributes(7).
+-----------------------------------+---------------+---------+
|Interface | Attribute | Value |
+-----------------------------------+---------------+---------+
|if_nametoindex(), if_indextoname() | Thread safety | MT-Safe |
+-----------------------------------+---------------+---------+
CONFORMING TO
POSIX.1-2001, POSIX.1-2008, RFC 3493.
This function first appeared in BSDi.
SEE ALSO getifaddrs(3), if_nameindex(3), ifconfig(8)COLOPHON
This page is part of release 4.15 of the Linux man-pages project. A description of the project, information about reporting bugs, and the
latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.
GNU 2017-09-15 IF_NAMETOINDEX(3)