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/*
* getmacaddr.c - get mac address for ethernet interface
*
* Copyright 2003 Red Hat, Inc.
*
* Michael Fulbright <msf@redhat.com>
*
* This software may be freely redistributed under the terms of the GNU
* general public license.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <sys/ioctl.h>
#include <net/if.h>
/* returns NULL or allocated string */
char *getMacAddr(char *ifname) {
int i;
int sock;
char *rcstr;
struct ifreq ifr;
if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
return NULL;
/* Setup our control structures. */
memset(&ifr, 0, sizeof(ifr));
strcpy(ifr.ifr_name, ifname);
if (ioctl(sock, SIOCGIFHWADDR, &ifr) < 0)
return NULL;
rcstr = (char *) malloc(24);
*rcstr = '\0';
for (i=0; i<6; i++) {
char tmp[4];
sprintf(tmp, "%02X",(unsigned char)ifr.ifr_hwaddr.sa_data[i]);
strcat(rcstr,tmp);
if (i != 5)
strcat(rcstr, ":");
}
return rcstr;
}
#ifdef TESTING
int main() {
printf("%s\n", getMacAddr("eth0"));
}
#endif
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