.\" Copyright (c) 1993 Michael Haardt (michael@moria.de),
.\"     Fri Apr  2 11:32:09 MET DST 1993
.\"
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.\" Modified Sat Jul 24 17:00:12 1993 by Rik Faith (faith@cs.unc.edu)
.TH NULL 4 2009-02-23 "Linux" "Linux Programmer's Manual"
.SH NAME
null, zero \- data sink
.SH DESCRIPTION
Data written to a
.BR null
or
.B zero
special file is discarded.
.PP
Reads from the
.B null
special file always return end of file (i.e.,
.BR read (2)
returns 0), whereas
reads from
.B zero
always return bytes containing zero (\e0 characters).
.LP
.B null
and
.B zero
are typically created by:
.RS
.sp
mknod \-m 666 /dev/null c 1 3
.br
mknod \-m 666 /dev/zero c 1 5
.br
chown root:root /dev/null /dev/zero
.RE
.SH FILES
.I /dev/null
.br
.I /dev/zero
.SH NOTES
If these devices are not writable and readable for all users, many
programs will act strangely.
.SH SEE ALSO
.BR chown (1),
.BR mknod (1),
.BR full (4)
.SH COLOPHON
This page is part of release 3.74 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
\%http://www.kernel.org/doc/man\-pages/.