dir(5)
NAME
dir − format of directories
SYNTAX
#include <sys/dir.h>
DESCRIPTION
A directory behaves exactly like an ordinary file, except that no user may write into a directory. The fact that a file is a directory is indicated by a bit in the flag word of its inode entry. For further information, see filsys(5). The structure of a directory entry as given in the include file is:
#ifndef DIRSIZ
#define DIRSIZ 14
#endif
struct direct
{
ino_t d_ino;
char d_name[DIRSIZ];
};
By convention, the first two entries in each directory are for “.” and “..”. The first is an entry for the directory itself. The second is for the parent directory. The meaning of “..” is modified for the root directory of the master file system and for the root directories of removable file systems. In the first case, there is no parent, and in the second, the system does not permit off-device references. Therefore in both cases “..” has the same meaning as “.”.