1.\" $NetBSD: byteorder.3,v 1.9 2002/02/07 07:00:20 ross Exp $ 2.\" 3.\" Copyright (c) 1983, 1991, 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. All advertising materials mentioning features or use of this software 15.\" must display the following acknowledgement: 16.\" This product includes software developed by the University of 17.\" California, Berkeley and its contributors. 18.\" 4. Neither the name of the University nor the names of its contributors 19.\" may be used to endorse or promote products derived from this software 20.\" without specific prior written permission. 21.\" 22.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32.\" SUCH DAMAGE. 33.\" 34.\" @(#)byteorder.3 8.1 (Berkeley) 6/4/93 35.\" 36.Dd June 4, 1993 37.Dt BYTEORDER 3 38.Os 39.Sh NAME 40.Nm htonl , 41.Nm htons , 42.Nm ntohl , 43.Nm ntohs 44.Nd convert values between host and network byte order 45.Sh LIBRARY 46.Lb libc 47.Sh SYNOPSIS 48.Fd #include \*[Lt]sys/types.h\*[Gt] 49.Ft in_addr_t 50.Fn htonl "in_addr_t host32" 51.Ft in_port_t 52.Fn htons "in_port_t host16" 53.Ft in_addr_t 54.Fn ntohl "in_addr_t net32" 55.Ft in_port_t 56.Fn ntohs "in_port_t net16" 57.Sh DESCRIPTION 58These routines convert 16 and 32 bit quantities between network 59byte order and host byte order. The types 60.Ft in_addr_t 61and 62.Ft in_port_t 63are defined by X/Open as: 64.Bd -literal -offset indent 65typedef u_int32_t in_addr_t; 66typedef u_int16_t in_port_t; 67.Ed 68.Pp 69On machines which have a byte order which is the same as the network 70order, routines are defined as null macros. 71.Pp 72These routines are most often used in conjunction with Internet 73addresses and ports as returned by 74.Xr gethostbyname 3 75and 76.Xr getservent 3 . 77.Sh SEE ALSO 78.Xr gethostbyname 3 , 79.Xr getservent 3 80.Sh HISTORY 81The 82.Nm byteorder 83functions appeared in 84.Bx 4.2 . 85.Sh BUGS 86The `l' and `s' suffixes in the names are not meaningful in machines 87where long integers are not 32 bits. 88