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.Dd September 9, 2019 32.Dt EUC 5 33.Os 34.Sh NAME 35.Nm euc 36.Nd EUC encoding of wide characters 37.Sh SYNOPSIS 38.Nm ENCODING 39.Qq EUC 40.Pp 41.Nm VARIABLE 42.Ar len1 43.Ar mask1 44.Ar len2 45.Ar mask2 46.Ar len3 47.Ar mask3 48.Ar len4 49.Ar mask4 50.Ar mask 51.Sh DESCRIPTION 52.\"The 53.\".Nm EUC 54.\"encoding is provided for compatibility with 55.\".Ux 56.\"based systems. 57.\"See 58.\".Xr localedef 1 59.\"for a complete description of the 60.\".Ev LC_CTYPE 61.\"source file format. 62.\".Pp 63.Nm EUC 64implements a system of 4 multibyte codesets. 65A multibyte character in the first codeset consists of 66.Ar len1 67bytes starting with a byte in the range of 0x00 to 0x7f. 68To allow use of 69.Tn ASCII , 70.Ar len1 71is always 1. 72A multibyte character in the second codeset consists of 73.Ar len2 74bytes starting with a byte in the range of 0x80-0xff excluding 0x8e and 0x8f. 75A multibyte character in the third codeset consists of 76.Ar len3 77bytes starting with the byte 0x8e. 78A multibyte character in the fourth codeset consists of 79.Ar len4 80bytes starting with the byte 0x8f. 81.Pp 82The 83.Vt wchar_t 84encoding of 85.Nm EUC 86multibyte characters is dependent on the 87.Ar len 88and 89.Ar mask 90arguments. 91First, the bytes are moved into a 92.Vt wchar_t 93as follows: 94.Bd -literal 95byte0 << ((\fIlen\fPN-1) * 8) | byte1 << ((\fIlen\fPN-2) * 8) | ... | byte\fIlen\fPN-1 96.Ed 97.Pp 98The result is then ANDed with 99.Ar ~mask 100and ORed with 101.Ar maskN . 102Codesets 2 and 3 are special in that the leading byte (0x8e or 0x8f) is 103first removed and the 104.Ar lenN 105argument is reduced by 1. 106.Pp 107For example, the 108.Li ja_JP.eucJP 109locale has the following 110.Va VARIABLE 111line: 112.Bd -literal 113VARIABLE 1 0x0000 2 0x8080 2 0x0080 3 0x8000 0x8080 114.Ed 115.Pp 116Codeset 1 consists of the values 0x0000 - 0x007f. 117.Pp 118Codeset 2 consists of the values who have the bits 0x8080 set. 119.Pp 120Codeset 3 consists of the values 0x0080 - 0x00ff. 121.Pp 122Codeset 4 consists of the values 0x8000 - 0xff7f excluding the values 123which have the 0x0080 bit set. 124.Pp 125Notice that the global 126.Ar mask 127is set to 0x8080, this implies that from those 2 bits the codeset can 128be determined. 129.Sh SEE ALSO 130.Xr localedef 1 , 131.Xr setlocale 3 132