Provided by:
manpages-dev_2.17-1_all 
NAME
readdir - read a directory
SYNOPSIS
#include <sys/types.h>
#include <dirent.h>
struct dirent *readdir(DIR *dir);
DESCRIPTION
The readdir() function returns a pointer to a dirent structure
representing the next directory entry in the directory stream pointed
to by dir. It returns NULL on reaching the end-of-file or if an error
occurred.
On Linux, the dirent structure is defined as follows:
struct dirent {
ino_t d_ino; /* inode number */
off_t d_off; /* offset to the next dirent */
unsigned short d_reclen; /* length of this record */
unsigned char d_type; /* type of file */
char d_name[256]; /* filename */
};
According to POSIX, the dirent structure contains a field char d_name[]
of unspecified size, with at most NAME_MAX characters preceding the
terminating null character. POSIX 1003.1-2001 also documents the field
ino_t d_ino as an XSI extension. Use of other fields will harm the
portability of your programs.
The data returned by readdir() may be overwritten by subsequent calls
to readdir() for the same directory stream.
RETURN VALUE
The readdir() function returns a pointer to a dirent structure, or NULL
if an error occurs or end-of-file is reached. On error, errno is set
appropriately.
ERRORS
EBADF Invalid directory stream descriptor dir.
CONFORMING TO
SVID 3, 4.3BSD, POSIX 1003.1-2001
SEE ALSO
read(2), closedir(3), dirfd(3), opendir(3), rewinddir(3), scandir(3),
seekdir(3), telldir(3)
1996-04-22 READDIR(3)