.\" 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)
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.\" Traduzione in italiano di Giovanni Bortolozzo <borto@dei.unipd.it>
.\" Settembre 1996
.\" Aggiornamento a man-pages-2.11 di Giulio Daprelà <giulio@pluto.it>
.\" novembre 2005
.\"
.TH NULL 4 "21 novembre 1992" "Linux" "Linux Programmer's Manual"
.SH NOME
null, zero \- data sink (scarico dei dati)
.SH DESCRIZIONE
I dati scritti su i file speciali \fBnull\fP e \fBzero\fP sono
scartati. 
.PP
Una lettura dal file speciale \fBnull\fP ritorna sempre un "end of
file", mentre una lettura da \fBzero\fP ritorna sempre caratteri \e0. 
.LP
\fBnull\fP e \fBzero\fP sono creati con:
.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
.sp
.RE
.SH NOTE
Se questi device speciali non sono scrivibili e leggibili da tutti gli
utenti, molti programmi si comporteranno stranamente.
.SH FILE
.I /dev/null
.br
.I /dev/zero
.SH "VEDERE ANCHE"
.BR chown (1),
.BR mknod (1)