Linux下判断网线是否插入的代码

Linux下判断网线是否插入的代码参考ethtool-2.6.36.tar.gz 代码：[guowenxue@localhost ~]$ sudo ethtool eth0Settings for eth0:        Supported ports: [ TP ]        Supported link modes:   10baseT/Half 10baseT/Full                                 100baseT/Half 100baseT/Full                                 1000baseT/Full         Supports auto-negotiation: Yes        Advertised link modes:  10baseT/Half 10baseT/Full                                 100baseT/Half 100baseT/Full                                 1000baseT/Full         Advertised auto-negotiation: Yes        Speed: 100Mb/s        Duplex: Full        Port: Twisted Pair        PHYAD: 0        Transceiver: internal        Auto-negotiation: on        Supports Wake-on: pumbg        Wake-on: g        Current message level: 0x00000033 (51)        Link detected: yes 下面是剥离开来的专门用来探测网线的源代码：[guowenxue@localhost ~]$ cat test.c #include <sys/types.h>#include <string.h>#include <stdlib.h>#include <sys/types.h>#include <sys/ioctl.h>#include <sys/stat.h>#include <stdio.h>#include <string.h>#include <errno.h>#include <net/if.h>#include <sys/utsname.h>#include <limits.h>#include <ctype.h> #include <sys/socket.h>#include <netinet/in.h>#include <arpa/inet.h> #include <linux/sockios.h> #define ETHTOOL_GLINK       0x0000000a /* Get link status (ethtool_value) */struct ethtool_value {            unsigned int   cmd;                unsigned int   data; };   int get_netlink_status(const char *if_name); int main(int argc, char *argv[]){    if (argc != 2)    {        fprintf(stderr, "usage: %s <ethname>\n", argv[0]);        return -1;    }    if (getuid() != 0)    {        fprintf(stderr, "Netlink Status Check Need Root user.\n");        return 1;    }     printf("Net link status: %s\n", get_netlink_status(argv[1]) == 1 ? "up" : "down");    return 0;} // if_name like "ath0", "eth0". Notice: call this function// need root privilege.// return value:// -1 -- error , details can check errno// 1 -- interface link up// 0 -- interface link down.int get_netlink_status(const char *if_name){    int skfd;    struct ifreq ifr;    struct ethtool_value edata;    edata.cmd = ETHTOOL_GLINK;    edata.data = 0;    memset(&ifr, 0, sizeof(ifr));    strncpy(ifr.ifr_name, if_name, sizeof(ifr.ifr_name) - 1);    ifr.ifr_data = (char *)&edata;    if ((skfd = socket(AF_INET, SOCK_DGRAM, 0)) == 0)        return -1;    if (ioctl(skfd, SIOCETHTOOL, &ifr) == -1)    {        close(skfd);        return -1;    }    close(skfd);    return edata.data;}  /tmp >: ifconfigeth0      Link encap:Ethernet  HWaddr 00:60:C2:69:06:B5            inet addr:10.78.28.114  Bcast:10.78.28.255  Mask:255.255.255.0          UP BROADCAST RUNNING MULTICAST MTU:1500  Metric:1   这里RUNNING可以看出eth1的网线插好了          RX packets:498 errors:0 dropped:0 overruns:0 frame:0          TX packets:117 errors:0 dropped:0 overruns:0 carrier:0          collisions:0 txqueuelen:1000           RX bytes:56899 (55.5 KiB)  TX bytes:11718 (11.4 KiB)          Interrupt:111 Base address:0x6000  eth1      Link encap:Ethernet  HWaddr 00:60:C2:69:06:B6            inet addr:192.168.2.1  Bcast:192.168.2.255  Mask:255.255.255.0          UP BROADCAST MULTICAST  MTU:1500  Metric:1   这里可以看出eth1的网线没插入          RX packets:0 errors:0 dropped:0 overruns:0 frame:0          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0          collisions:0 txqueuelen:1000           RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)          Interrupt:21 Base address:0x4000  lo        Link encap:Local Loopback            inet addr:127.0.0.1  Mask:255.0.0.0          UP LOOPBACK RUNNING  MTU:16436  Metric:1          RX packets:0 errors:0 dropped:0 overruns:0 frame:0          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0          collisions:0 txqueuelen:0           RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B) /tmp >: ./test eth0Net link status: up/tmp >: ./test eth1Net link status: down这段代码在AT91SAM9260+DM9000/DM9161上都能正常工作，但在W90P710上不能工作，可能是W90P710的DM9000的驱动有问题。