readdir(2) - Linux man page

Name

readdir - read directory entry

Synopsis

int readdir(unsigned int fd, struct old_linux_dirent *dirp,
            unsigned int count);

Description

This is not the function you are interested in. Look at readdir(3) for the POSIX conforming C library interface. This page documents the bare kernel system call interface, which is superseded by getdents(2).

readdir() reads one old_linux_dirent structure from the directory referred to by the file descriptor fd into the buffer pointed to by dirp. The argument count is ignored; at most one old_linux_dirent structure is read.

The old_linux_dirent structure is declared as follows:

struct old_linux_dirent {
    long  d_ino;              /* inode number */
    off_t d_off;              /* offset to this old_linux_dirent */
    unsigned short d_reclen;  /* length of this d_name */
    char  d_name[NAME_MAX+1]; /* filename (null-terminated) */
}

d_ino is an inode number. d_off is the distance from the start of the directory to this old_linux_dirent. d_reclen is the size of d_name, not counting the terminating null byte. d_name is a null-terminated filename.

Return Value

On success, 1 is returned. On end of directory, 0 is returned. On error, -1 is returned, and errno is set appropriately.

Errors

EBADF

Invalid file descriptor fd.

EFAULT

Argument points outside the calling process's address space.

EINVAL

Result buffer is too small.

ENOENT

No such directory.

ENOTDIR

File descriptor does not refer to a directory.

Conforming To

This system call is Linux-specific.

Notes

Glibc does not provide a wrapper for this system call; call it using syscall(2). You will need to define the old_linux_dirent structure yourself. However, probably you should use readdir(3) instead.

See Also

getdents(2), readdir(3)

Referenced By