Plan 9 from Bell Labs’s /usr/web/sources/contrib/anothy/src/lib/djb-ape/unix/socket_getifidx.c
#include <sys/types.h> #include <sys/socket.h> /*#include <net/if.h>*/ #include "socket.h" #include "haven2i.h" uint32 socket_getifidx(const char* ifname) { #ifdef HAVE_N2I return if_nametoindex(ifname); #else return 0; #endif }