.\" Copyright (C) 1995 Andries Brouwer (aeb@cwi.nl)

.\"

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.\" Written 11 June 1995 by Andries Brouwer <aeb@cwi.nl>

.\" Modified 22 July 1995 by Michael Chastain <mec@duracef.shout.net>:

.\"   In 1.3.X, returns only one entry each time; return value is different.

.\" Modified 2004-12-01, mtk, fixed headers listed in SYNOPSIS

.\"

.TH READDIR 2  2017-09-15 "Linux" "Linux Programmer's Manual"

.SH NAME

readdir \- read directory entry

.SH SYNOPSIS

.nf

.PP

.BI "int readdir(unsigned int " fd ", struct old_linux_dirent *" dirp ","

.BI "            unsigned int " count );

.fi

.PP

.IR Note :

There is no glibc wrapper for this system call; see NOTES.

.SH DESCRIPTION

This is not the function you are interested in.

Look at

.BR readdir (3)

for the POSIX conforming C library interface.

This page documents the bare kernel system call interface,

which is superseded by

.BR getdents (2).

.PP

.BR readdir ()

reads one

.I old_linux_dirent

structure from the directory

referred to by the file descriptor

.I fd

into the buffer pointed to by

.IR dirp .

The argument

.I count

is ignored; at most one

.I old_linux_dirent

structure is read.

.PP

The

.I old_linux_dirent

structure is declared as follows:

.PP

.in +4n

.EX

struct old_linux_dirent {

    long  d_ino;              /* inode number */

    off_t d_off;              /* offset to this \fIold_linux_dirent\fP */

    unsigned short d_reclen;  /* length of this \fId_name\fP */

    char  d_name[NAME_MAX+1]; /* filename (null-terminated) */

}

.EE

.in

.PP

.I d_ino

is an inode number.

.I d_off

is the distance from the start of the directory to this

.IR old_linux_dirent .

.I d_reclen

is the size of

.IR d_name ,

not counting the terminating null byte (\(aq\\0\(aq).

.I d_name

is a null-terminated filename.

.SH RETURN VALUE

On success, 1 is returned.

On end of directory, 0 is returned.

On error, \-1 is returned, and

.I errno

is set appropriately.

.SH ERRORS

.TP

.B EBADF

Invalid file descriptor

.IR fd .

.TP

.B EFAULT

Argument points outside the calling process's address space.

.TP

.B EINVAL

Result buffer is too small.

.TP

.B ENOENT

No such directory.

.TP

.B ENOTDIR

File descriptor does not refer to a directory.

.SH CONFORMING TO

This system call is Linux-specific.

.SH NOTES

Glibc does not provide a wrapper for this system call; call it using

.BR syscall (2).

You will need to define the

.I old_linux_dirent

structure yourself.

However, probably you should use

.BR readdir (3)

instead.

.PP

This system call does not exist on x86-64.

.SH SEE ALSO

.BR getdents (2),

.BR readdir (3)

.SH COLOPHON

This page is part of release 4.15 of the Linux

.I man-pages

project.

A description of the project,

information about reporting bugs,

and the latest version of this page,

can be found at

\%https://www.kernel.org/doc/man\-pages/.