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.\" @(#)isalpha.3 8.1 (Berkeley) 6/4/93 33.\" $FreeBSD: head/lib/libc/locale/isalpha.3 233992 2012-04-07 09:05:30Z joel $ 34.\" 35.Dd July 17, 2005 36.Dt ISALPHA 3 37.Os 38.Sh NAME 39.Nm isalpha , 40.Nm isalpha_l 41.Nd alphabetic character test 42.Sh LIBRARY 43.Lb libc 44.Sh SYNOPSIS 45.In ctype.h 46.Ft int 47.Fn isalpha "int c" 48.In ctype.h 49.In xlocale.h 50.Ft int 51.Fn isalpha_l "int c" "locale_t loc" 52.Sh DESCRIPTION 53The 54.Fn isalpha 55function tests for any character for which 56.Xr isupper 3 57or 58.Xr islower 3 59is true. 60The value of the argument must be representable as an 61.Vt "unsigned char" 62or the value of 63.Dv EOF . 64.Pp 65In the ASCII character set, this includes the following characters 66(with their numeric values shown in octal): 67.Bl -column \&000_``0''__ \&000_``0''__ \&000_``0''__ \&000_``0''__ \&000_``0''__ 68.It "\&101\ ``A''" Ta "102\ ``B''" Ta "103\ ``C''" Ta "104\ ``D''" Ta "105\ ``E''" 69.It "\&106\ ``F''" Ta "107\ ``G''" Ta "110\ ``H''" Ta "111\ ``I''" Ta "112\ ``J''" 70.It "\&113\ ``K''" Ta "114\ ``L''" Ta "115\ ``M''" Ta "116\ ``N''" Ta "117\ ``O''" 71.It "\&120\ ``P''" Ta "121\ ``Q''" Ta "122\ ``R''" Ta "123\ ``S''" Ta "124\ ``T''" 72.It "\&125\ ``U''" Ta "126\ ``V''" Ta "127\ ``W''" Ta "130\ ``X''" Ta "131\ ``Y''" 73.It "\&132\ ``Z''" Ta "141\ ``a''" Ta "142\ ``b''" Ta "143\ ``c''" Ta "144\ ``d''" 74.It "\&145\ ``e''" Ta "146\ ``f''" Ta "147\ ``g''" Ta "150\ ``h''" Ta "151\ ``i''" 75.It "\&152\ ``j''" Ta "153\ ``k''" Ta "154\ ``l''" Ta "155\ ``m''" Ta "156\ ``n''" 76.It "\&157\ ``o''" Ta "160\ ``p''" Ta "161\ ``q''" Ta "162\ ``r''" Ta "163\ ``s''" 77.It "\&164\ ``t''" Ta "165\ ``u''" Ta "166\ ``v''" Ta "167\ ``w''" Ta "170\ ``x''" 78.It "\&171\ ``y''" Ta "172\ ``z''" Ta \& Ta \& Ta \& 79.El 80.Pp 81The 82.Fn isalpha_l 83function takes an explicit locale argument, whereas the 84.Fn isalpha 85function uses the current global or per-thread locale. 86.Sh RETURN VALUES 87The 88.Fn isalpha 89function returns zero if the character tests false and 90returns non-zero if the character tests true. 91.Sh COMPATIBILITY 92The 93.Bx 4.4 94extension of accepting arguments outside of the range of the 95.Vt "unsigned char" 96type in locales with large character sets is considered obsolete 97and may not be supported in future releases. 98The 99.Fn iswalpha 100function should be used instead. 101.Sh SEE ALSO 102.Xr ctype 3 , 103.Xr ctype_l 3 , 104.Xr islower 3 , 105.Xr isupper 3 , 106.Xr iswalpha 3 , 107.Xr xlocale 3 , 108.Xr ascii 7 109.Sh STANDARDS 110The 111.Fn isalpha 112function conforms to 113.St -isoC . 114The 115.Fn isalpha_l 116function conforms to 117.St -p1003.1-2008 . 118