Lokale IP-Adresse

ip address show

AWK=`which awk`
IFCONFIG="which ifconfig"
SED=`which sed`
NIC="dsl0" # adapt nic
IP="`$IFCONFIG $NIC 2>/dev/null|$AWK '/inet addr:/ {print $2}'|$SED 's/addr://'`"

/** 
  * hack to grab interface information 
  */

#include <sys/socket.h> 
#include <net/if.h> 
#include <netinet/in.h> 
#include <stdio.h> 
#include <stdlib.h> 


#define SIOCGIFCONF     0x8912          /* get iface list               */

int main(int argc, char *argv[]) { 
  int numreqs = 30, sd, n, tick, found=0;
  struct ifconf ifc; 
  struct ifreq *ifr; 
  struct in_addr *ia;

  sd=socket(AF_INET, SOCK_STREAM, 0); 
  ifc.ifc_buf = NULL; 
  ifc.ifc_len = sizeof(struct ifreq) * numreqs; 
  ifc.ifc_buf = realloc(ifc.ifc_buf, ifc.ifc_len); 
  
  if (ioctl(sd, SIOCGIFCONF, &ifc) < 0) { 
    exit(1);
  } 
  
  ifr = ifc.ifc_req; 
  
  for (n = 0; n < ifc.ifc_len; n += sizeof(struct ifreq)) { 
    ia= (struct in_addr *)((ifr->ifr_ifru.ifru_addr.sa_data)+2); 

    fprintf(stdout, "%6s %-15s\n", ifr->ifr_ifrn.ifrn_name, inet_ntoa(*ia));
   
    ifr++; 
  }

  free(ifc.ifc_buf);
  return 0;
}