1.\" Copyright (c) 1991, 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.\" the American National Standards Committee X3, on Information 6.\" Processing Systems. 7.\" 8.\" Redistribution and use in source and binary forms, with or without 9.\" modification, are permitted provided that the following conditions 10.\" are met: 11.\" 1. Redistributions of source code must retain the above copyright 12.\" notice, this list of conditions and the following disclaimer. 13.\" 2. Redistributions in binary form must reproduce the above copyright 14.\" notice, this list of conditions and the following disclaimer in the 15.\" documentation and/or other materials provided with the distribution. 16.\" 3. 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.\" @(#)isxdigit.3 8.1 (Berkeley) 6/4/93 33.\" $FreeBSD$ 34.\" 35.Dd July 17, 2005 36.Dt ISXDIGIT 3 37.Os 38.Sh NAME 39.Nm isxdigit , 40.Nm ishexnumber 41.Nd hexadecimal-digit character test 42.Sh LIBRARY 43.Lb libc 44.Sh SYNOPSIS 45.In ctype.h 46.Ft int 47.Fn isxdigit "int c" 48.Ft int 49.Fn ishexnumber "int c" 50.Sh DESCRIPTION 51The 52.Fn isxdigit 53function tests for any hexadecimal-digit character. 54Regardless of locale, this includes the following characters only: 55.Bl -column \&``0''______ \&``0''______ \&``0''______ \&``0''______ \&``0''______ 56.It "\&``0''" Ta "``1''" Ta "``2''" Ta "``3''" Ta "``4''" 57.It "\&``5''" Ta "``6''" Ta "``7''" Ta "``8''" Ta "``9''" 58.It "\&``A''" Ta "``B''" Ta "``C''" Ta "``D''" Ta "``E''" 59.It "\&``F''" Ta "``a''" Ta "``b''" Ta "``c''" Ta "``d''" 60.It "\&``e''" Ta "``f''" Ta \& Ta \& Ta \& 61.El 62.Pp 63The 64.Fn ishexnumber 65function behaves similarly to 66.Fn isxdigit , 67but may recognize additional characters, 68depending on the current locale setting. 69.Pp 70The value of the argument must be representable as an 71.Vt "unsigned char" 72or the value of 73.Dv EOF . 74.Sh RETURN VALUES 75The 76.Fn isxdigit 77function returns zero if the character tests false and 78returns non-zero if the character tests true. 79.Sh COMPATIBILITY 80The 81.Bx 4.4 82extension of accepting arguments outside of the range of the 83.Vt "unsigned char" 84type in locales with large character sets is considered obsolete 85and may not be supported in future releases. 86The 87.Fn iswxdigit 88function should be used instead. 89.Sh SEE ALSO 90.Xr ctype 3 , 91.Xr iswxdigit 3 , 92.Xr ascii 7 93.Sh STANDARDS 94The 95.Fn isxdigit 96function conforms to 97.St -isoC . 98.Sh HISTORY 99The 100.Fn ishexnumber 101function appeared in 102.Bx 4.4 . 103