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.\" @(#)byteorder.3 8.1 (Berkeley) 6/4/93 33.\" $FreeBSD$ 34.\" 35.Dd June 4, 1993 36.Dt BYTEORDER 3 37.Os BSD 4.2 38.Sh NAME 39.Nm htonl , 40.Nm htons , 41.Nm ntohl , 42.Nm ntohs 43.Nd convert values between host and network byte order 44.Sh LIBRARY 45.Lb libc 46.Sh SYNOPSIS 47.Fd #include <sys/param.h> 48.Ft u_long 49.Fn htonl "u_long hostlong" 50.Ft u_short 51.Fn htons "u_short hostshort" 52.Ft u_long 53.Fn ntohl "u_long netlong" 54.Ft u_short 55.Fn ntohs "u_short netshort" 56.Sh DESCRIPTION 57These routines convert 16 and 32 bit quantities between network 58byte order and host byte order. 59On machines which have a byte order which is the same as the network 60order, routines are defined as null macros. 61.Pp 62These routines are most often used in conjunction with Internet 63addresses and ports as returned by 64.Xr gethostbyname 3 65and 66.Xr getservent 3 . 67.Sh SEE ALSO 68.Xr gethostbyname 3 , 69.Xr getservent 3 70.Sh HISTORY 71The 72.Nm byteorder 73functions appeared in 74.Bx 4.2 . 75.Sh BUGS 76On the 77.Tn VAX 78bytes are handled backwards from most everyone else in 79the world. This is not expected to be fixed in the near future. 80