linux下C编程_获取指定网卡IP信息

来源：互联网发布：晓组织衣服淘宝编辑：程序博客网时间：2024/06/10 17:13

自己实现的，不一定通用，其实就是从 ifconfig 结果里面提取信息

# ifconfigeth0      Link encap:Ethernet  HWaddr 00:03:AD:BC:CC:5A          inet addr:192.168.100.238  Bcast:192.168.100.255  Mask:255.255.255.0          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1          RX packets:5089 errors:0 dropped:0 overruns:0 frame:0          TX packets:604 errors:0 dropped:0 overruns:0 carrier:0          collisions:0 txqueuelen:1000          RX bytes:1226762 (1.1 MiB)  TX bytes:60168 (58.7 KiB)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:275 errors:0 dropped:0 overruns:0 frame:0          TX packets:275 errors:0 dropped:0 overruns:0 carrier:0          collisions:0 txqueuelen:0          RX bytes:12172 (11.8 KiB)  TX bytes:12172 (11.8 KiB)

  23 #define NET_NAME        "eth0"  24 #define NET_INFO_LEN    20  25 #define IFCONFIG_CMD    "ifconfig"  26 #define NET_INFO_BUFF_SIZE 350  93 /*  94 *       本地网络信息  95 */  96 struct Network {  97         char ipaddr[NET_INFO_LEN];      /* IP地址 */  98         char mask[NET_INFO_LEN];        /* 子网掩码 */  99         char gateway[NET_INFO_LEN];     /* 网关 */ 100         char mac[NET_INFO_LEN];         /* MAC地址*/ 101 };17211722 /*1723 *       获取本机IP地址 eth0网卡1724 */1725 int get_net_info(struct Network *netinfo)1726 {1727         /* 待搜索网卡名称 */1728         char network_name[READ_BUFF_SIZE] = NET_NAME;1729         char net_info[NET_INFO_BUFF_SIZE] = {0};1730         char temp[READ_BUFF_SIZE] = {0};1731         char read_tmp[READ_BUFF_SIZE] = {0};1732         FILE *fp = NULL;1733         int i = 0;1734         int j = 0;1735 #if 11736         fp = popen(IFCONFIG_CMD, "r");1737         if (fp == NULL) {1738                 dbg_out(DBG_ERR, "popen failed\n");1739                 return -1;1740         } else {1741                 /* 开始解析 */1742                 if (fread(net_info, sizeof(char), sizeof(net_info), fp) != sizeof(net_info)) {1743                         dbg_out(DBG_ERR, "fread %s failed\n", net_info);1744                         pclose(fp);1745                         return -1;1746                 }1747                 pclose(fp);17481749                 /* 匹配网卡名称 */1750                 strncpy(temp, net_info, strlen(network_name));1751                 if (strcmp(temp, network_name) != 0) {1752                         return -1;1753                 }1754                 i = i + strlen(network_name);17551756                 /* 物理地址 HWaddr */1757                 memset(read_tmp, 0, sizeof(read_tmp));1758                 memset(temp, 0, sizeof(temp));1759                 strcat(temp, "HWaddr ");1760                 while (net_info[i] != '\0') {1761                         /* 查找"HWaddr "*/1762                         if (net_info[i] != 'H') {1763                                 i++;1764                                 continue;1765                         }1766                         for (j=0; j<strlen(temp); j++) {1767                                 read_tmp[j] = net_info[i];1768                                 i++;1769                         }17701771                         /* 相等则拷贝 */1772                         if (!strcmp(temp, read_tmp)) {1773                                 for (j=0; j<17; j++) {  /* mac 固定长度 */1774                                         netinfo->mac[j] = net_info[i];1775                                         i++;1776                                 }1777                                 netinfo->mac[j] = '\0';1778                                 break;1779                         } else {1780                                 dbg_out(DBG_INFO, "find \"HWADDR \" failed\n");1781                                 return -1;1782                         }1783                 }1784                 dbg_out(DBG_INFO, "MAC: %s\n", netinfo->mac);1785                 dbg_out(DBG_INFO, "MAC len: %d\n", strlen(netinfo->mac));17861787                 /* ip地址 inet addr: */1788                 memset(read_tmp, 0, sizeof(read_tmp));1789                 memset(temp, 0, sizeof(temp));1790                 strcat(temp, "inet addr:");1791                 while (net_info[i] != '\0') {1792                         /* 查找 i */1793                         if (net_info[i] != 'i') {1794                                 i++;1795                                 continue;1796                         }1797                         for (j=0; j<strlen(temp); j++) {1798                                 read_tmp[j] = net_info[i];1799                                 i++;1800                         }18011802                         /* 相等则拷贝 */1803                         if (!strcmp(temp, read_tmp)) {1804                                 j = 0;1805                                 while (net_info[i] != ' ') {1806                                         netinfo->ipaddr[j] = net_info[i];1807                                         i++;1808                                         j++;1809                                 }1810                                 netinfo->ipaddr[j] = '\0';1811                                 break;1812                         } else {1813                                 dbg_out(DBG_INFO, "find \"ipaddr\" failed\n");1814                                 return -1;1815                         }1816                 }1817                 dbg_out(DBG_INFO, "ip: %s\n", netinfo->ipaddr);1818                 dbg_out(DBG_INFO, "ip len: %d\n", strlen(netinfo->ipaddr));18191820                 /* Bcast: */1821                 memset(read_tmp, 0, sizeof(read_tmp));1822                 memset(temp, 0, sizeof(temp));1823                 strcat(temp, "Bcast:");1824                 while (net_info[i] != '\0') {1825                         /* 查找 B */1826                         if (net_info[i] != 'B') {1827                                 i++;1828                                 continue;1829                         }1830                         for (j=0; j<strlen(temp); j++) {1831                                 read_tmp[j] = net_info[i];1832                                 i++;1833                         }18341835                         /* 相等则拷贝 */1836                         if (!strcmp(temp, read_tmp)) {1837                                 j = 0;1838                                 while (net_info[i] != ' ') {1839                                         netinfo->gateway[j] = net_info[i];1840                                         i++;1841                                         j++;1842                                 }1843                                 netinfo->gateway[j] = '\0';1844                                 break;1845                         } else {1846                                 dbg_out(DBG_INFO, "find \"gateway\" failed\n");1847                                 return -1;1848                         }1849                 }1850                 dbg_out(DBG_INFO, "Bcast: %s\n", netinfo->gateway);1851                 dbg_out(DBG_INFO, "Bcast len: %d\n", strlen(netinfo->gateway));18521853                 /* 子网掩码 Mask: */1854                 memset(read_tmp, 0, sizeof(read_tmp));1855                 memset(temp, 0, sizeof(temp));1856                 strcat(temp, "Mask:");1857                 while (net_info[i] != '\0') {1858                         /* 查找M */1859                         if (net_info[i] != 'M') {1860                                 i++;1861                                 continue;1862                         }1863                         for (j=0; j<strlen(temp); j++) {1864                                 read_tmp[j] = net_info[i];1865                                 i++;1866                         }18671868                         /* 相等则拷贝 */1869                         if (!strcmp(temp, read_tmp)) {1870                                 j = 0;1871                                 while (net_info[i] != '\n') {1872                                         netinfo->mask[j] = net_info[i];1873                                         i++;1874                                         j++;1875                                 }1876                                 netinfo->mask[j] = '\0';1877                                 break;1878                         } else {1879                                 dbg_out(DBG_INFO, "find \"mask\" failed\n");1880                                 return -1;1881                         }1882                 }1883                 dbg_out(DBG_INFO, "mask: %s\n", netinfo->mask);1884                 dbg_out(DBG_INFO, "mask len: %d\n", strlen(netinfo->mask));1885         }18861887         return 0;1888 #endif1889 }

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