#include <stdlib.h>#include <stdio.h>#include <string.h>#include <unistd.h>  #include <sys/socket.h>#include <sys/ioctl.h>#include <linux/if.h>#include <linux/mii.h>#include <linux/sockios.h>#include <errno.h> #include <ifaddrs.h>#include <arpa/inet.h>  #include <linux/ethtool.h> int cshell_netlink_status(char *if_name){ char  buffer[BUFSIZ]; char  cmd[100]; FILE  *read_fp; int    chars_read; int    ret =0;  memset( buffer, 0, BUFSIZ ); memset( cmd, 0, 100 ); sprintf(cmd, "ifconfig -a | grep %s",if_name); read_fp = popen(cmd, "r"); if ( read_fp != NULL ) { chars_read = fread(buffer, sizeof(char), BUFSIZ-1, read_fp); pclose(read_fp);  if (chars_read > 0) {  ret = 1; } else {  fprintf(stderr, "DEVICE_NONE/r/n");  return 0; } }  if(ret == 1) { memset( buffer, 0, BUFSIZ ); memset( cmd, 0, 100 ); sprintf(cmd, "ifconfig |grep %s",if_name); read_fp = popen(cmd, "r"); if ( read_fp != NULL ) {  chars_read = fread(buffer, sizeof(char), BUFSIZ-1, read_fp);  pclose(read_fp);   if (chars_read > 0)  {  ret = 2;  }  else  {  fprintf(stderr, "DEVICE_DOWN/r/n");  return 1;  } } }  if(ret == 2) { memset( buffer, 0, BUFSIZ ); memset( cmd, 0, 100 ); sprintf(cmd, "ifconfig %s | grep RUNNING | awk '{print $3}'",if_name); read_fp = popen(cmd, "r"); if ( read_fp != NULL ) {   chars_read = fread(buffer, sizeof(char), BUFSIZ-1, read_fp);   pclose(read_fp);     if (chars_read > 0)   {  fprintf(stderr, "DEVICE_LINKED/r/n");  return 3;   }   else   {  fprintf(stderr, "DEVICE_UNPLUGGED/r/n");  return 2;   } } }  return -1;}  int c_netlink_status(const char *if_name ){ int fd = -1;  struct ifreq ifr;   struct ifconf ifc;  struct ifreq ifrs_buf[100];  int if_number =0; int i;   if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) { fprintf(stderr, "%s: socket error [%d] %s/r/n",if_name, errno, strerror(errno)); close(fd); return -1;  }  ifc.ifc_len = sizeof(ifrs_buf);  ifc.ifc_buf = (caddr_t)ifrs_buf;  if (ioctl(fd, SIOCGIFCONF, (char *)&ifc) <0)  { fprintf(stderr, "%s: ioctl SIOCGIFCONF error [%d] %s/r/n",if_name, errno, strerror(errno)); close(fd); return -1;  }  if_number = ifc.ifc_len / sizeof(struct ifreq); for(i=0; i< if_number; i++) { if(strcmp(if_name,ifrs_buf[i].ifr_name ) == 0) {  break; } }  if(i >= if_number) { close(fd); fprintf(stderr, "DEVICE_NONE/r/n"); return 0; }  bzero(&ifr, sizeof(ifr)); strncpy(ifr.ifr_name, if_name, IFNAMSIZ-1);  ifr.ifr_name[IFNAMSIZ-1] = 0;  if (ioctl(fd, SIOCGIFFLAGS, (char *)&ifr) <0)  { fprintf(stderr, "%s: ioctl SIOCGIFFLAGS error [%d] %s/r/n",if_name, errno, strerror(errno)); close(fd); return -1;  }#if 1  if(!(ifr.ifr_flags & IFF_UP)) { close(fd); fprintf(stderr, "DEVICE_DOWN/r/n"); return 1; }  if(!(ifr.ifr_flags & IFF_RUNNING)) { close(fd); fprintf(stderr, "DEVICE_UNPLUGGED/r/n"); return 2 ; }  fprintf(stderr, "DEVICE_LINKED/r/n"); return 3; #else{ struct ethtool_value edata; if(!(ifr.ifr_flags & IFF_UP) || !(ifr.ifr_flags & IFF_RUNNING)) { close(fd); fprintf(stderr, "%s: DOWN/r/n",if_name); return 1; } edata.cmd = ETHTOOL_GLINK; edata.data = 0; ifr.ifr_data = (char *) &edata; if(ioctl( fd, SIOCETHTOOL, &ifr ) < 0) { fprintf(stderr, "%s: ioctl SIOCETHTOOL error [%d] %s/r/n",if_name, errno, strerror(errno)); close(fd); return -1;  }  if(edata.data == 0) { fprintf(stderr, "DEVICE_UNPLUGGED/r/n"); return 2;  } else { fprintf(stderr, "DEVICE_LINKED/r/n"); return 3;  }}#endif} int main(int argc, char* argv[]){ int i=0; if(argc != 2) { fprintf(stderr, "usage: %s <ethname>/r/n", argv[0]); return -1; }  i = cshell_netlink_status(argv[1]);  printf( "cshell_netlink_status if_status = %d/n", i );  i = c_netlink_status(argv[1]); printf( "c_netlink_status if_status = %d/n", i );  return 0;}