gcc filename.c -lpcap && sudo ./a.out

#include <pcap.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>

int main()
{
   char pcap_errbuf[PCAP_ERRBUF_SIZE];
   char perrbuf[PCAP_ERRBUF_SIZE];
   pcap_t *pcap = NULL;
   // pcap_lookupdev(perrbuf) // finds the first suitable interface
   pcap = pcap_open_live(/*pcap_lookupdev(perrbuf)*/"eth0", UINT16_MAX, 1, 0, pcap_errbuf);
   if(pcap==NULL)
      printf("\n\nPCAP NULL, error buffer value is: %s\n\n", pcap_errbuf);

   return EXIT_SUCCESS;
}