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.\" 4. 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: head/lib/libc/locale/isxdigit.3 233992 2012-04-07 09:05:30Z joel $ 34.\" 35.Dd July 17, 2005 36.Dt ISXDIGIT 3 37.Os 38.Sh NAME 39.Nm isxdigit , isxdigit_l , ishexnumber , ishexnumber_l 40.Nd hexadecimal-digit character test 41.Sh LIBRARY 42.Lb libc 43.Sh SYNOPSIS 44.In ctype.h 45.Ft int 46.Fn isxdigit "int c" 47.Ft int 48.Fn ishexnumber "int c" 49.In ctype.h 50.In xlocale.h 51.Ft int 52.Fn isxdigit_l "int c" "locale_t loc" 53.Ft int 54.Fn ishexnumber_l "int c" "locale_t loc" 55.Sh DESCRIPTION 56The 57.Fn isxdigit 58function tests for any hexadecimal-digit character. 59Regardless of locale, this includes the following characters only: 60.Bl -column \&``0''______ \&``0''______ \&``0''______ \&``0''______ \&``0''______ 61.It "\&``0''" Ta "``1''" Ta "``2''" Ta "``3''" Ta "``4''" 62.It "\&``5''" Ta "``6''" Ta "``7''" Ta "``8''" Ta "``9''" 63.It "\&``A''" Ta "``B''" Ta "``C''" Ta "``D''" Ta "``E''" 64.It "\&``F''" Ta "``a''" Ta "``b''" Ta "``c''" Ta "``d''" 65.It "\&``e''" Ta "``f''" Ta \& Ta \& Ta \& 66.El 67.Pp 68The 69.Fn ishexnumber 70function behaves similarly to 71.Fn isxdigit , 72but may recognize additional characters, 73depending on the current locale setting. 74.Pp 75The value of the argument must be representable as an 76.Vt "unsigned char" 77or the value of 78.Dv EOF . 79.Pp 80The _l-suffixed versions take an explicit locale argument, whereas the 81non-suffixed versions use the current global or per-thread locale. 82.Sh RETURN VALUES 83The 84.Fn isxdigit 85function returns zero if the character tests false and 86returns non-zero if the character tests true. 87.Sh COMPATIBILITY 88The 89.Bx 4.4 90extension of accepting arguments outside of the range of the 91.Vt "unsigned char" 92type in locales with large character sets is considered obsolete 93and may not be supported in future releases. 94The 95.Fn iswxdigit 96function should be used instead. 97.Sh SEE ALSO 98.Xr ctype 3 , 99.Xr ctype_l 3 , 100.Xr iswxdigit 3 , 101.Xr xlocale 3 , 102.Xr ascii 7 103.Sh STANDARDS 104The 105.Fn isxdigit 106function conforms to 107.St -isoC . 108.Sh HISTORY 109The 110.Fn ishexnumber 111function appeared in 112.Bx 4.4 . 113