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.\"	$OpenBSD: gethostid.3,v 1.13 2013/07/17 05:42:10 schwarze Exp $
.\"
.Dd $Mdocdate: July 17 2013 $
.Dt GETHOSTID 3
.Os
.Sh NAME
.Nm gethostid ,
.Nm sethostid
.Nd get/set unique identifier of current host
.Sh SYNOPSIS
.In unistd.h
.Ft long
.Fn gethostid void
.Ft int
.Fn sethostid "long hostid"
.Sh DESCRIPTION
The
.Fn sethostid
function establishes a 32-bit identifier for the
current processor that is intended to be unique among all
UNIX systems in existence.
This is normally a DARPA Internet address for the local machine.
This call is allowed only to the
superuser 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
system calls first appeared in
.Bx 4.1c
and were dropped in
.Bx 4.4 .
.Sh BUGS
32 bits for the identifier is too small.