如何列出C程序中的目录中的文件?

I'm trying to write an ftp server on Linux. In this matter how can I list files in the directory on terminal by a C program? Maybe I can use exec function to run find command but I want file name as a string to send client program. How can I do this?

我想在Linux上写一个ftp服务器。在这个问题上，我如何能列出文件在终端的目录通过一个C程序?也许我可以使用exec函数来运行find命令，但是我希望文件名作为字符串来发送客户端程序。我该怎么做呢?

Thanks for answers.

谢谢你的答案。

3 个解决方案

#1

142

An example, available for POSIX compliant systems :

一个示例，适用于POSIX兼容系统:

/*
 * This program displays the names of all files in the current directory.
 */

#include <dirent.h> 
#include <stdio.h> 

int main(void) {
  DIR *d;
  struct dirent *dir;
  d = opendir(".");
  if (d) {
    while ((dir = readdir(d)) != NULL) {
      printf("%s\n", dir->d_name);
    }
    closedir(d);
  }
  return(0);
}

Beware that such an operation is platform dependant in C.

注意，这样的操作在C中是依赖于平台的。

Source : http://faq.cprogramming.com/cgi-bin/smartfaq.cgi?answer=1046380353&id=1044780608

来源:http://faq.cprogramming.com/cgi-bin/smartfaq.cgi?answer=1046380353&id=1044780608

#2

One tiny addition to JB Jansen's answer - in the main readdir() loop I'd add this:

JB Jansen的回答中增加了一点——在主readdir()循环中，我将添加以下内容:

  if (dir->d_type == DT_REG)
  {
     printf("%s\n", dir->d_name);
  }

Just checking if it's really file, not (sym)link, directory, or whatever.

只是检查它是否是真正的文件，而不是(sym)链接、目录或其他。

NOTE: more about struct dirent in libc documentation.

注意:更多关于libc文档中的struct dirent的信息。

#3

Here is a complete program how to recursively list folder's contents:

这是一个完整的程序如何递归列出文件夹的内容:

#include <dirent.h> 
#include <stdio.h> 
#include <string.h>

#define NORMAL_COLOR  "\x1B[0m"
#define GREEN  "\x1B[32m"
#define BLUE  "\x1B[34m"



/* let us make a recursive function to print the content of a given folder */

void show_dir_content(char * path)
{
  DIR * d = opendir(path); // open the path
  if(d==NULL) return; // if was not able return
  struct dirent * dir; // for the directory entries
  while ((dir = readdir(d)) != NULL) // if we were able to read somehting from the directory
    {
      if(dir-> d_type != DT_DIR) // if the type is not directory just print it with blue
        printf("%s%s\n",BLUE, dir->d_name);
      else
      if(dir -> d_type == DT_DIR && strcmp(dir->d_name,".")!=0 && strcmp(dir->d_name,"..")!=0 ) // if it is a directory
      {
        printf("%s%s\n",GREEN, dir->d_name); // print its name in green
        char d_path[255]; // here I am using sprintf which is safer than strcat
        sprintf(d_path, "%s/%s", path, dir->d_name);
        show_dir_content(d_path); // recall with the new path
      }
    }
    closedir(d); // finally close the directory
}

int main(int argc, char **argv)
{

  printf("%s\n", NORMAL_COLOR);

    show_dir_content(argv[1]);

  printf("%s\n", NORMAL_COLOR);
  return(0);
}

#1

142