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.\" Copyright (c) 1993 Michael Haardt (u31b3hs@pool.informatik.rwth-aachen.de), Fri Apr 2 11:32:09 MET DST 1993
.\"
.\" This is free documentation; you can redistribute it and/or
.\" modify it under the terms of the GNU General Public License as
.\" published by the Free Software Foundation; either version 2 of
.\" the License, or (at your option) any later version.
.\"
.\" The GNU General Public License's references to "object code"
.\" and "executables" are to be interpreted as the output of any
.\" document formatting or typesetting system, including
.\" intermediate and printed output.
.\"
.\" This manual is distributed in the hope that it will be useful,
.\" but WITHOUT ANY WARRANTY; without even the implied warranty of
.\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
.\" GNU General Public License for more details.
.\"
.\" You should have received a copy of the GNU General Public
.\" License along with this manual; if not, write to the Free
.\" Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139,
.\" USA.
.\"
.\" Modified Sat Jul 24 17:00:12 1993 by Rik Faith (faith@cs.unc.edu)
.\"
.\" Traduzione in italiano di Giovanni Bortolozzo <borto@dei.unipd.it>
.\" Settembre 1996
.\"
.\" " for hilit19
.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:mem /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
/dev/null
.br
/dev/zero
.SH "VEDERE ANCHE"
.BR mknod "(1), " chown (1)
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