/* net/if.h -- declarations for inquiring about network interfaces Copyright (C) 2000-2024 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, see . */ #ifndef _NET_IF_H #define _NET_IF_H 1 #include __BEGIN_DECLS /* Convert an interface name to an index, and vice versa. */ extern unsigned int if_nametoindex (const char *__ifname) __THROW; extern char *if_indextoname (unsigned int __ifindex, char *__ifname) __THROW; /* Return a list of all interfaces and their indices. */ struct if_nameindex { unsigned int if_index; /* 1, 2, ... */ char *if_name; /* null terminated name: "eth0", ... */ }; extern struct if_nameindex *if_nameindex (void) __THROW; /* Free the data returned from if_nameindex. */ extern void if_freenameindex (struct if_nameindex *__ptr) __THROW; __END_DECLS #endif /* net/if.h */