dwhitney67
July 27th, 2010, 04:42 PM
Very interesting code, but it's slightly to complex for me, is there possible any simpler or a guide where the basics are taught?
Here's another spin on the reference provided by VH-BIL, however I'm unsure if it handles IPv6...
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <net/if.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <sys/ioctl.h>
int main(void)
{
int iSocket = -1;
struct if_nameindex* pIndex = 0;
struct if_nameindex* pIndex2 = 0;
if ((iSocket = socket(PF_INET, SOCK_DGRAM, 0)) < 0)
{
perror("socket");
return -1;
}
pIndex = pIndex2 = if_nameindex();
while ((pIndex != NULL) && (pIndex->if_name != NULL))
{
struct ifreq req;
printf("%d: %s\n", pIndex->if_index, pIndex->if_name);
strncpy(req.ifr_name, pIndex->if_name, IFNAMSIZ);
if (ioctl(iSocket, SIOCGIFADDR, &req) < 0)
{
if (errno == EADDRNOTAVAIL)
{
printf("\tN/A\n");
++pIndex;
continue;
}
perror("ioctl");
close(iSocket);
return -1;
}
printf("\t %s\n", inet_ntoa(((struct sockaddr_in*)&req.ifr_addr)->sin_addr));
++pIndex;
}
if_freenameindex(pIndex2);
close(iSocket);
return 0;
}