1.\" Copyright (c) 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" This code is derived from software contributed to Berkeley by 5.\" Paul Borman at Krystal Technologies. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions 9.\" are met: 10.\" 1. Redistributions of source code must retain the above copyright 11.\" notice, this list of conditions and the following disclaimer. 12.\" 2. Redistributions in binary form must reproduce the above copyright 13.\" notice, this list of conditions and the following disclaimer in the 14.\" documentation and/or other materials provided with the distribution. 15.\" 3. Neither the name of the University nor the names of its contributors 16.\" may be used to endorse or promote products derived from this software 17.\" without specific prior written permission. 18.\" 19.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29.\" SUCH DAMAGE. 30.\" 31.\" @(#)euc.4 8.1 (Berkeley) 6/4/93 32.\" $FreeBSD$ 33.\" 34.Dd November 8, 2003 35.Dt EUC 5 36.Os 37.Sh NAME 38.Nm euc 39.Nd EUC encoding of wide characters 40.Sh SYNOPSIS 41.Nm ENCODING 42.Qq EUC 43.Pp 44.Nm VARIABLE 45.Ar len1 46.Ar mask1 47.Ar len2 48.Ar mask2 49.Ar len3 50.Ar mask3 51.Ar len4 52.Ar mask4 53.Ar mask 54.Sh DESCRIPTION 55.\"The 56.\".Nm EUC 57.\"encoding is provided for compatibility with 58.\".Ux 59.\"based systems. 60.\"See 61.\".Xr mklocale 1 62.\"for a complete description of the 63.\".Ev LC_CTYPE 64.\"source file format. 65.\".Pp 66.Nm EUC 67implements a system of 4 multibyte codesets. 68A multibyte character in the first codeset consists of 69.Ar len1 70bytes starting with a byte in the range of 0x00 to 0x7f. 71To allow use of 72.Tn ASCII , 73.Ar len1 74is always 1. 75A multibyte character in the second codeset consists of 76.Ar len2 77bytes starting with a byte in the range of 0x80-0xff excluding 0x8e and 0x8f. 78A multibyte character in the third codeset consists of 79.Ar len3 80bytes starting with the byte 0x8e. 81A multibyte character in the fourth codeset consists of 82.Ar len4 83bytes starting with the byte 0x8f. 84.Pp 85The 86.Vt wchar_t 87encoding of 88.Nm EUC 89multibyte characters is dependent on the 90.Ar len 91and 92.Ar mask 93arguments. 94First, the bytes are moved into a 95.Vt wchar_t 96as follows: 97.Bd -literal 98byte0 << ((\fIlen\fPN-1) * 8) | byte1 << ((\fIlen\fPN-2) * 8) | ... | byte\fIlen\fPN-1 99.Ed 100.Pp 101The result is then ANDed with 102.Ar ~mask 103and ORed with 104.Ar maskN . 105Codesets 2 and 3 are special in that the leading byte (0x8e or 0x8f) is 106first removed and the 107.Ar lenN 108argument is reduced by 1. 109.Pp 110For example, the 111.Li ja_JP.eucJP 112locale has the following 113.Va VARIABLE 114line: 115.Bd -literal 116VARIABLE 1 0x0000 2 0x8080 2 0x0080 3 0x8000 0x8080 117.Ed 118.Pp 119Codeset 1 consists of the values 0x0000 - 0x007f. 120.Pp 121Codeset 2 consists of the values who have the bits 0x8080 set. 122.Pp 123Codeset 3 consists of the values 0x0080 - 0x00ff. 124.Pp 125Codeset 4 consists of the values 0x8000 - 0xff7f excluding the values 126which have the 0x0080 bit set. 127.Pp 128Notice that the global 129.Ar mask 130is set to 0x8080, this implies that from those 2 bits the codeset can 131be determined. 132.Sh SEE ALSO 133.Xr mklocale 1 , 134.Xr setlocale 3 135