NAME | DESCRIPTION | FILES | NOTES | SEE ALSO | COLOPHON

NULL(4)                       Linux Programmer's Manual                       NULL(4)

NAME         top

       null, zero - data sink

DESCRIPTION         top

       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         top

       /dev/null
       /dev/zero

NOTES         top

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

SEE ALSO         top

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

COLOPHON         top

       This page is part of release 3.23 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                                 2009-02-23                              NULL(4)