1.\" $NetBSD: ctype.3,v 1.17 2007/01/20 13:11:36 wiz Exp $ 2.\" 3.\" Copyright (c) 1991 Regents of the University of California. 4.\" All rights reserved. 5.\" 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.\" @(#)ctype.3 6.5 (Berkeley) 4/19/91 32.\" 33.Dd January 18, 2007 34.Dt CTYPE 3 35.Os 36.Sh NAME 37.Nm isalpha , 38.Nm isupper , 39.Nm islower , 40.Nm isdigit , 41.Nm isxdigit , 42.Nm isalnum , 43.Nm isspace , 44.Nm ispunct , 45.Nm isprint , 46.Nm isgraph , 47.Nm iscntrl , 48.Nm isblank , 49.Nm toupper , 50.Nm tolower , 51.Nd character classification and mapping functions 52.Sh LIBRARY 53.Lb libc 54.Sh SYNOPSIS 55.In ctype.h 56.Fa int c 57.br 58.Fn isalpha c 59.Fn isupper c 60.Fn islower c 61.Fn isdigit c 62.Fn isxdigit c 63.Fn isalnum c 64.Fn isspace c 65.Fn ispunct c 66.Fn isprint c 67.Fn isgraph c 68.Fn iscntrl c 69.Fn isblank c 70.Fn toupper c 71.Fn tolower c 72.Sh DESCRIPTION 73The above functions perform character tests and conversions on the integer 74.Ar c . 75.Pp 76See the specific manual pages for more information. 77.Sh EXAMPLES 78To print an upper-case version of a string on stdout, use the following 79code: 80.Bd -literal 81const char *s = ...; 82while (*s != '\\0') { 83 putchar(toupper((unsigned char)*s)); 84 s++; 85} 86.Ed 87.Sh SEE ALSO 88.Xr isalnum 3 , 89.Xr isalpha 3 , 90.Xr isblank 3 , 91.Xr iscntrl 3 , 92.Xr isdigit 3 , 93.Xr isgraph 3 , 94.Xr islower 3 , 95.Xr isprint 3 , 96.Xr ispunct 3 , 97.Xr isspace 3 , 98.Xr isupper 3 , 99.Xr isxdigit 3 , 100.Xr tolower 3 , 101.Xr toupper 3 , 102.Xr ascii 7 103.Sh STANDARDS 104These functions, with the exception of 105.Fn isblank , 106conform to 107.St -ansiC . 108.Sh CAVEATS 109The first parameter of these functions is of type int, but only a very 110restricted subset is actually valid as an argument. 111The argument must either be the value of the macro 112.Dv EOF 113or representable as an unsigned char. 114Otherwise the behavior is undefined. 115When testing an expression having the type 116.Tn plain char , 117the argument should be cast to an unsigned char. 118