1 .\" Copyright (c) 1993 Michael Haardt (michael@moria.de),
2 .\" Fri Apr 2 11:32:09 MET DST 1993
4 .\" %%%LICENSE_START(GPLv2+_DOC_FULL)
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25 .\" Modified Sat Jul 24 17:00:12 1993 by Rik Faith (faith@cs.unc.edu)
26 .TH NULL 4 2015-07-23 "Linux" "Linux Programmer's Manual"
28 null, zero \- data sink
34 special files is discarded.
38 always return end of file (i.e.,
40 returns 0), whereas reads from
42 always return bytes containing zero (\(aq\e0\(aq characters).
44 These devices are typically created by:
48 mknod \-m 666 /dev/null c 1 3
49 mknod \-m 666 /dev/zero c 1 5
50 chown root:root /dev/null /dev/zero
58 If these devices are not writable and readable for all users, many
59 programs will act strangely.
62 .\" commit 2b83868723d090078ac0e2120e06a1cc94dbaef0
65 are interruptible by signals.
66 (This change was made to help with bad latencies for large reads from