1.\" Copyright (c) 1983, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. All advertising materials mentioning features or use of this software 13.\" must display the following acknowledgement: 14.\" This product includes software developed by the University of 15.\" California, Berkeley and its contributors. 16.\" 4. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)gethostname.3 8.1 (Berkeley) 6/4/93 33.\" $FreeBSD: src/lib/libc/gen/gethostname.3,v 1.5.2.6 2003/03/13 18:05:37 trhodes Exp $ 34.\" $DragonFly: src/lib/libc/gen/gethostname.3,v 1.4 2006/05/26 19:39:36 swildner Exp $ 35.\" 36.Dd June 4, 1993 37.Dt GETHOSTNAME 3 38.Os 39.Sh NAME 40.Nm gethostname , 41.Nm sethostname 42.Nd get/set name of current host 43.Sh LIBRARY 44.Lb libc 45.Sh SYNOPSIS 46.In unistd.h 47.Ft int 48.Fn gethostname "char *name" "int namelen" 49.Ft int 50.Fn sethostname "const char *name" "int namelen" 51.Sh DESCRIPTION 52The 53.Fn gethostname 54function 55returns the standard host name for the current processor, as 56previously set by 57.Fn sethostname . 58The 59.Fa namelen 60argument 61specifies the size of the 62.Fa name 63array. The returned name is null-terminated unless insufficient 64space is provided. 65.Pp 66The 67.Fn sethostname 68function 69sets the name of the host machine to be 70.Fa name , 71which has length 72.Fa namelen . 73This call is restricted to the super-user and 74is normally used only when the system is bootstrapped. 75.Sh RETURN VALUES 76.Rv -std 77.Sh ERRORS 78The following errors may be returned by these calls: 79.Bl -tag -width Er 80.It Bq Er EFAULT 81The 82.Fa name 83or 84.Fa namelen 85argument gave an 86invalid address. 87.It Bq Er EPERM 88The caller tried to set the hostname and was not the super-user. 89.El 90.Sh SEE ALSO 91.Xr gethostid 3 , 92.Xr sysctl 3 93.Sh HISTORY 94The 95.Fn gethostname 96function appeared in 97.Bx 4.2 . 98.Sh BUGS 99Host names are limited to 100.Dv MAXHOSTNAMELEN 101(from 102.In sys/param.h ) 103characters, currently 256. 104This includes the trailing 105.Dv NUL . 106