Question

我对C ++还是很陌生，我正在尝试创建一个实用程序，该实用程序可以找到所有网络设备并列出其名称和MAC地址。我已经编译了所有内容，但是当我运行to_string()方法时，没有任何输出到终端。我相信我正在访问迭代器对象，并错误地对其调用to_string()。

//networkinterfacelist_class.cpp
#include "networkinterfacelist.h"

//get list of network interfaces and push them into a vector list
networkinterfacelist_class::networkinterfacelist_class(){
  if ((dir = opendir ("/sys/class/net")) != NULL){
    while ((ent = readdir (dir)) != NULL) {
      std::string device(ent->d_name);

      //skips the parent and current folder
      if(device == "." || device == ".."){
        continue;
      }

      dir_list.push_back(device);
    }
    closedir (dir);
  }
}

//iterate through the devices and find their mac addresses
std::vector<networkinterface_class> networkinterfacelist_class::create_device(){
  for( std::vector<std::string>::iterator it = dir_list.begin(); it != dir_list.end(); ++it){
    if ((dir2 = opendir ("/sys/class/net")) != NULL){
      if ((dir = opendir (it->c_str())) != NULL){

        //opens the address file saves mac address in line
        inFile.open("address");
        while(!inFile){
          getline(inFile, line);
        }

        //creates a new networkinterface class and pushes it onto a list
        networkinterface_class obj( *it , line);
        list.push_back(obj);

      }
    }
  }
  return list;
}

//iterates over the list of network devices and prints their name and mac address
void networkinterfacelist_class::to_string(){
  for(std::vector<networkinterface_class>::iterator it = list.begin(); it != list.end(); ++it){
    (*it).to_string();
  }
}

和我的networkinterface类

//networkinterface_class.cpp
#include "networkinterface.h"

networkinterface_class::networkinterface_class(std::string device, std::string macaddress){
  name = device;
  mac = macaddress;
}

std::string networkinterface_class::get_name(){
  return name;
}

std::string networkinterface_class::get_mac(){
  return mac;
}

void networkinterface_class::to_string(){
  std::cout << "Name: " << networkinterface_class::get_name() << "\tMAC: " << networkinterface_class::get_mac() << std::endl;
}

任何帮助或提示将不胜感激

Answer 1

您需要为设备定义整个路径。

dir_list.push_back(device); // it pushes only d_name of dirent == filename

在上面的行中，您仅推送/sys/class/net中的设备名称，因此，当您要读取此设备时，需要通过将 / sys / class / net / 与设备名称

if ((dir = opendir ( ("/sys/class/net/" + *it).c_str() )) != NULL){
                                          ^^^ get device name as string

代替

if ((dir = opendir (it->c_str())) != NULL){ // you pass only device without full path

要打开address文件时，请执行以下操作：

inFile.open("/sys/class/net/" + *it + "/address");

现在您可以阅读此文件的内容。

访问矢量迭代器元素以输出

1 个答案: