#include <assert.h>
#include <stdlib.h>
#include <net/if.h>
#include <stdio.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <unistd.h>
int main(int argc, char **argv) {
int fd = socket(AF_UNIX, SOCK_STREAM, 0);
struct ifreq ifreqs[20];
struct ifconf ifc;
ifc.ifc_ifcu.ifcu_req = ifreqs;
#ifndef POSITIVE
ifc.ifc_len = sizeof(ifreqs);
#endif
int res = ioctl(fd, SIOCGIFCONF, (void *)&ifc);
assert(res == 0);
for (int i = 0; i < ifc.ifc_len / sizeof(*ifc.ifc_ifcu.ifcu_req); ++i)
printf("%d %zu %s\n", i, strlen(ifreqs[i].ifr_name), ifreqs[i].ifr_name);
return 0;
}