NULL(4) Linux Programmers Manual NULL(4)
null, zero - data sink
Data written on a null or zero special file is discarded.
Reads from the null special file always return end of file, whereas
reads from zero always return \0 characters.
null and zero are typically created by:
mknod -m 666 /dev/null c 1 3
mknod -m 666 /dev/zero c 1 5
chown root:root /dev/null /dev/zero
If these devices are not writable and readable for all users, many pro
grams will act strangely.
chown(1), mknod(1), full(4)
This page is part of release 3.05 of the Linux man-pages project. A
description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.
Linux 1992-11-21 NULL(4)