Linux network programming face question----------all directories and files in the statistics directory

The topics are as follows:

Implement a single function of Linux under tree [only prints the number of directories and the number of files (no hidden files)]

Preferred we introduce several related Linux system APIs

Name of function	Function description	function declaration
Opendir	Open a directory, successfully return a dir* type pointer, failure to return null	dir* opendir (const char* name)
Readdir	Reads a child member under an open directory, returns a struct pointer successfully, otherwise returns null	struct dirent* readdir (dir* DIR)
Closedir	Close the Open directory. Successful return 0, failure return-1	int Closedir (dir* dirp)

struct Dirent Structural body #include <dirent.h>//need to include header files struct dirent{ ino_t D_ino; index [inode] Number off_t D_off; Offset in the catalog file unsigned short d_reclen; File name length unsigned char d_type; File type Char d_name[256]; Filename } D_type all file types to be addressed DT_BLK Block Equipment DT_CHR character device Dt_dir Directory Dt_fifo Famous Pipe Dt_lnk Symbolic Link (soft link) Dt_reg Common Files Dt_sock Socket Socket Dt_unknown Unknown type

Precautions:

L The Linux directory has.　And.. Represents the current directory and the top-level directory, respectively, and does not process a dead loop

2. Do not include hidden files, you need to use ordinary files to ignore processing

The code is as follows:

#include <stdio.h> //input/output header file

#include <stdlib.h> //eixt () function header file

#include <unistd.h> //unix Standard library header files

#include <sys/types.h> //opendir () Closedir () Readdir () required header file

#include <dirent.h> //Ibid .

#include <string.h> //String Common API header file

//function function

Successful return to Exit_success

Failed to return exit_failure

int Mytree (const char* root, unsigned int* const dirs, unsigned int* const files) {

int ret = exit_success; //return value

dir* dir = NULL; //Open Directory

char path[1024] = {0}; //splicing file relative path use

struct dirent* ptr = NULL; //Read the directory under the member struct

//Judging parameters

if (NULL = = Root | | NULL = = Dirs | | NULL = = files) {

//Error hints

printf ("func%s err:[null = = Root | | NULL = = Dirs | | NULL = = Files] ", __function__);

//exit directly

ret = exit_failure;

Goto END;

}

//Open Directory

Dir = opendir (root);

//Determine if Open failed

if (NULL = = dir) {

//Friendship Error Tips

Perror ("Func tree->opendir Error:");

ret = exit_failure;

Goto END;

}

//Iterate through the file members in the directory

while (NULL! = (ptr = Readdir (dir))) {

//Determine if the. and: Directories, or. Start of hidden files

if (0 = = strncmp (ptr->d_name, ".", 1) | | 0 = = strcmp (Ptr->d_name, "...")) {

Continue //Skip processing

}

//If it is a directory

if (Dt_dir = = Ptr->d_type) {

(*dirs) + +; //Directory number +1

sprintf (Path, "%s/%s", root, ptr->d_name);

mytree (path, dirs, files);

}else{

(*files) + +;

}

}

END:

//Determine if the directory is closed

if (NULL! = dir) {

Closedir (dir);

dir = NULL;

}
return ret;

}

Main function

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

unsigned int dirs = 0; //Statistics Directory number

unsigned int files = 0; //Number of statistics files

//Judging command line arguments

if (2 > ARGC) {

//No parameters, default statistics under current directory

Mytree (".", &dirs, &files);

}

else{

int i = 0;

//Multiple parameters in case

for (i = 1; i < argc; i++) {

Mytree (Argv[i], &dirs, &files);

}

}

//Output final statistic information

printf ("%d directories,%d files\n", dirs, files);

return exit_success;

}

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Linux network programming face question----------all directories and files in the statistics directory