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.\"	$NetBSD: gethostid.3,v 1.13 2019/03/03 20:34:43 maya Exp $
.\"
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.\"     @(#)gethostid.3	8.1 (Berkeley) 6/2/93
.\"
.Dd March 3, 2019
.Dt GETHOSTID 3
.Os
.Sh NAME
.Nm gethostid ,
.Nm sethostid
.Nd get/set unique identifier of current host
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In unistd.h
.Ft long
.Fn gethostid void
.Ft int
.Fn sethostid "long hostid"
.Sh DESCRIPTION
.Fn sethostid
establishes a 32-bit identifier for the current processor that is
intended to be unique among all
.Ux
systems in existence.
This is normally an Internet address for the local machine.
This call is allowed only to the super-user and is normally performed
at boot time.
.Pp
.Fn gethostid
returns the 32-bit identifier for the current processor.
.Pp
This function has been deprecated.
The hostid should be set or retrieved by use of
.Xr sysctl 3 .
.Sh SEE ALSO
.Xr gethostname 3 ,
.Xr sysctl 3 ,
.Xr sysctl 8
.Sh HISTORY
The
.Fn gethostid
and
.Fn sethostid
syscalls appeared in
.Bx 4.2
and were dropped in
.Bx 4.4 .
.Sh BUGS
32 bits for the identifier is too small.