====== Prelevare e settare informazioni interfacce di rete ======
Autore: **//Fabio Di Matteo//** \\ Ultima revisione: **//21/03/2008//** \\ \\
Ecco delle pratiche funzioni get/set utili per prelevare e settare informazioni sulle interfacce di rete:


<code c>
#include <stdio.h>
#include <errno.h>
#include <string.h> 
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <netinet/in.h>
#include <net/if.h>
#include <arpa/inet.h> 


int SetIP(const char* interface,const char * adress)
{
 int test_sock=0;
 struct sockaddr_in* addr=NULL;
 struct ifreq ifr;

 memset( &ifr, 0, sizeof( struct ifreq ) );
 addr= (struct sockaddr_in *)&(ifr.ifr_addr);
 memset(addr, 0, sizeof( struct sockaddr_in) );
 addr->sin_len=sizeof(struct sockaddr_in);
 addr->sin_family=AF_INET;
 addr->sin_addr.s_addr=inet_addr(adress);

 test_sock = socket( PF_INET, SOCK_DGRAM, 0 );
 if( test_sock == -1 )
 {
  diag_printf("Cannot obtain socket :%s\n",strerror(errno));
  return (-1);
 }

 strncpy( ifr.ifr_name,interface,IFNAMSIZ);
 if( ioctl( test_sock, SIOCSIFADDR, &ifr ) != 0 )
 {
  diag_printf("Cannot set IP address of interface '%s' to 
'%s':%s\n",interface,adress,strerror(errno));
  close(test_sock);
  return (-1);
 }
 else diag_printf("IP address of '%s' set to '%s'\n",interface,adress);
 close(test_sock);
 return(0);
}



int GetIP(const char* interface)
{
 int test_sock=0;
 struct sockaddr_in *addrp=NULL;
 struct ifreq ifr;

 test_sock = socket( PF_INET, SOCK_DGRAM, 0 );
 if( test_sock == -1 )
 {
  printf("Impossibile creare il socket :%s\n",strerror(errno));
  return (-1);
 }

 memset(&ifr,0,sizeof( struct ifreq ) );
 strncpy(ifr.ifr_name,interface,IFNAMSIZ);

 if( ioctl( test_sock, SIOCGIFADDR, &ifr ) == -1 )
 {
  printf("Impossibile ottenere indirizzo IP di '%s':%s\n",interface,strerror(errno));
  close(test_sock);
  return (-1);
 }
 close(test_sock);

 addrp = (struct sockaddr_in *)&(ifr.ifr_addr);
 printf("Indirizzo IP dell\' interfaccia '%s' e\' '%s'\n",interface,inet_ntoa(addrp->sin_addr));
 return(0);
}


int GetMAC(const char* interface){
	int fd;
 	struct ifreq ifr;

 	fd = socket(AF_INET, SOCK_DGRAM, 0);

 	ifr.ifr_addr.sa_family = AF_INET;
 	strncpy(ifr.ifr_name, interface, IFNAMSIZ-1);

 	ioctl(fd, SIOCGIFHWADDR, &ifr);

 	close(fd);

 	printf("%.2x:%.2x:%.2x:%.2x:%.2x:%.2x\n",
         (unsigned char)ifr.ifr_hwaddr.sa_data[0],
         (unsigned char)ifr.ifr_hwaddr.sa_data[1],
         (unsigned char)ifr.ifr_hwaddr.sa_data[2],
         (unsigned char)ifr.ifr_hwaddr.sa_data[3],
         (unsigned char)ifr.ifr_hwaddr.sa_data[4],
         (unsigned char)ifr.ifr_hwaddr.sa_data[5]);

}

int main()
{
 	GetIP("eth0");
	GetMAC("eth0");

return 0;
}





</code>