.\" Copyright (c) 1983, 1991, 1993
.\"     The Regents of the University of California.  All rights reserved.
.\"
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.\"    must display the following acknowledgement:
.\"     This product includes software developed by the University of
.\"     California, Berkeley and its contributors.
.\" 4. Neither the name of the University nor the names of its contributors
.\"    may be used to endorse or promote products derived from this software
.\"    without specific prior written permission.
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.\"     @(#)byteorder.3 8.1 (Berkeley) 6/4/93
.\" %FreeBSD: src/lib/libc/net/byteorder.3,v 1.3.2.4 2001/12/14 18:33:55 ru Exp %
.\"
.\" $FreeBSD$
.Dd June 4, 1993
.Dt BYTEORDER 3
.Os
.Sh 名称
.Nm htonl ,
.Nm htons ,
.Nm ntohl ,
.Nm ntohs
.Nd ホストバイトオーダとネットワークバイトオーダを変換する
.Sh ライブラリ
.Lb libc
.Sh 書式
.In sys/param.h
.Ft u_long
.Fn htonl "u_long hostlong"
.Ft u_short
.Fn htons "u_short hostshort"
.Ft u_long
.Fn ntohl "u_long netlong"
.Ft u_short
.Fn ntohs "u_short netshort"
.Sh 解説
これらのルーチンは、16 ビットと 32 ビットの値を、
ネットワークバイトオーダとホストバイトオーダの間で変換します。
ネットワークのオーダと同じバイトオーダのマシンでは、
ルーチンはヌルマクロとして定義されます。
.Pp
これらのルーチンは、
.Xr gethostbyname 3
および
.Xr getservent 3
によって返されるインターネットアドレスおよびポートとともに
使用されることが最もよくあります。
.Sh 関連項目
.Xr gethostbyname 3 ,
.Xr getservent 3
.Sh 歴史
.Nm byteorder
関数は
.Bx 4.2
で登場しました。
.Sh バグ
.Tn VAX
は、世界中の他のほとんどすべてのマシンとは逆順にバイトを処理します。
この問題は、当分解決の見込みはありません。