获取Linux网卡信息

代码示例获取网卡信息。

通过命令获取

• ARP(Address Resolution Protocol)地址解析协议。
• 执行cat /proc/net/arp得到以下信息：

ubuntu:~$ cat /proc/net/arp
IP address       HW type     Flags       HW address            Mask     Device
192.168.72.2     0x1         0x2         00:50:56:f4:70:28     *        ens33
192.168.72.254   0x1         0x2         00:50:56:ed:51:f7     *        ens33

其中，HW type为硬件类型

值	类型
0x01	ether (Ethernet)
0xf	dlci (Frame Relay DLCI)
0x17	strip (Metricom Starmode IP)

通过代码获取

#include <stdio.h>
#include <string.h>
#include <iostream>
#include <list>

using namespace std;

struct NetworkInfo {
    string deviceName;
    string ip;
    string mask;
    int hardwareType; /* 硬件类型 */
    string macAddress;
};

list<NetworkInfo> getAllNetworkInfo()
{
    list<NetworkInfo> result;
    char buf[128] = {0};

    FILE *fp = fopen("/proc/net/arp", "r");
    if (fp == NULL)
        return result;

    /* 移除第一行无关内容 */
    if (fgets(buf, sizeof(buf), fp) == NULL)
        return result;

    memset(buf, 0, sizeof(buf)); // 重置缓冲区
    while(fgets(buf, sizeof(buf), fp) != NULL) {
        
        char ip[16] = {0};
        char macAddress[32] = {0};
        char mask[16] = {0};
        char deviceName[512] = {0};
        int hardwareType = 0;
        int flags = 0;
        /* 读数据 */
        sscanf(buf, "%s 0x%x 0x%x %s %s %s\n",
               ip,
               &hardwareType,
               &flags,
               macAddress,
               mask,
               deviceName);

        /* 装载数据 */
        NetworkInfo info;
        info.deviceName = deviceName;
        info.ip = ip;
        info.mask = mask;
        info.hardwareType = hardwareType;
        info.macAddress = macAddress;

        result.push_back(info);

        memset(buf, 0, sizeof(buf)); // 重置缓冲区
    }

    fclose(fp);

    return result;
}