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If i want to write a C program in counting the no of file in a folder, what should i do?

Here is borrowed from Mr.Ritchie :D

Code:



#include <stdio.h>

#include <sys/types.h>

#include <sys/stat.h>

#include <fcntl.h>





#define NAME_MAX 10



typedef struct {

  int fd;

  char name [NAME_MAX + 1];

} Dirent;



typedef struct {

  int fd;

  Dirent d;

} Dir;



/* that's just for portability (Mohsen)*/



/* Now you can use 3 functions: */



DIR *opendir (char* dirname);

Dirent *readdir (DIR *dfd);

void closedir (char*, struct stat*)  

/*

The Dirent structure contains the inode 

number and the name. The maximium length of a file 

name component is NAME_MAX , which 

is a SYSTEM DEPENDENT value. opendir returns  

a pointer to a structure called DIR, 

analogous to FILE, which is used 

by readdir and closedir. 

*/

Now you may use stat system call to determine if your name is a directory (take a look at manual page of stat).

Code:

Dirent *dp;

DIR *dfd;



if ((dfd = opendir ("MyDirName")) == NULL)

  exit (1);



/* readdir returns 

file names in directory. dp->name may be `.' 

or `..' which should be ignored. */

while ((dp = readdir (dfd) != NULL) {

  if (strcmp (dp->name, ".") == 0 || strcmp (dp->name, "..")  == 0)

  continue;

  printf ("file: %s\n", dp->name);

}

P.S.
I'va wrote it in a hurry so check out the man pages on any question.

Quote:

Originally posted by dummyagain
If i want to write a C program in counting the no of file in a folder, what should i do?

It's pretty simple. Look at opendir(3), readdir(3), stat(3), and closedir(3). Here's an example:

Code:

#include <sys/types.h>

#include <sys/stat.h>

#include <dirent.h>

#include <stdio.h>

#include <unistd.h>



int main()

{

  struct dirent*  dirEntry  = NULL;

  DIR*            dirStream  = NULL;

  int            fileCount  = 0;

  struct stat    fileStats;



  dirStream  = opendir( "." );



  while( ( dirEntry = readdir( dirStream ) ) != NULL ) {



      stat( dirEntry->d_name, &fileStats );



      if( !S_ISDIR( fileStats.st_mode ) ) {

        printf( "%s\n", dirEntry->d_name );

        fileCount++;

      }



  }



  printf( "Total number of files: %d\n", fileCount );



  closedir( dirStream );



  return(0);

}

Of course, you should check each function call to make sure it succeeds.

This gives the number of files in directory....

Code:

#include<dirent.h>

#include <sys/stat.h>

int filter(const struct dirent *dir)

{

        struct stat BUFFER;

        stat(dir->d_name,&BUFFER);

        return !S_ISDIR(BUFFER.st_mode);

}

main()

{

        struct dirent **name_list;

        printf("%d",scandir(".",&name_list,filter,alphasort));

}