NULL(4)

NAME
null, zero - data sink

DESCRIPTION
Data written to a null or zero special file is discarded.

Reads from the null special file always return end of file (i.e., read(2) returns 0), whereas reads from zero always return bytes containing zero (\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

FILES
/dev/null
/dev/zero

NOTES
If these devices are not writable and readable for all users, many programs will act strangely.

SEE ALSO
chown(1), mknod(1), full(4)

COLOPHON
This page is part of release 3.41 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/.