Network Programming Cheat Sheet

in_addr_t to String

#include <arpa/inet.h>

in_addr_t ipAddr = inet_addr("127.0.0.1");

char buffer[INET_ADDRSTRLEN];
inet_ntop(AF_INET, &ipAddr, buffer, INET_ADDRSTRLEN);

printf("IP as String: %s\n", buffer);

IPv4 (AF_INET) From String to Binary Form

#include <arpa/inet.h>

uint32_t bits;
inet_pton(AF_INET, "127.0.0.1", &bits);

Ethernet Address to String

#include ???

struct ether_addr eth_addr;

// find ethernet adress and store it into eth_addr ...

printf("MAC: %s\n", ether_ntoa(&eth_addr));

String to Ethernet Address

#include ???

struct ether_addr *eth_addr = ether_aton(param_mac);
if (eth_addr == NULL)
{
    return;
}

printf("MAC: %s\n", ether_ntoa(eth_addr));

free(eth_addr);
eth_addr = NULL;