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.\" @(#)islower.3 8.1 (Berkeley) 6/4/93 33.\" $FreeBSD$ 34.\" 35.Dd July 17, 2005 36.Dt ISLOWER 3 37.Os 38.Sh NAME 39.Nm islower 40.Nd lower-case character test 41.Sh LIBRARY 42.Lb libc 43.Sh SYNOPSIS 44.In ctype.h 45.Ft int 46.Fn islower "int c" 47.Sh DESCRIPTION 48The 49.Fn islower 50function tests for any lower-case letters. 51The value of the argument must be representable as an 52.Vt "unsigned char" 53or the value of 54.Dv EOF . 55.Pp 56In the ASCII character set, this includes the following characters 57(with their numeric values shown in octal): 58.Pp 59.Bl -column \&000_``0''__ \&000_``0''__ \&000_``0''__ \&000_``0''__ \&000_``0''__ 60.It "\&141\ ``a'' \t142\ ``b'' \t143\ ``c'' \t144\ ``d'' \t145\ ``e''" 61.It "\&146\ ``f'' \t147\ ``g'' \t150\ ``h'' \t151\ ``i'' \t152\ ``j''" 62.It "\&153\ ``k'' \t154\ ``l'' \t155\ ``m'' \t156\ ``n'' \t157\ ``o''" 63.It "\&160\ ``p'' \t161\ ``q'' \t162\ ``r'' \t163\ ``s'' \t164\ ``t''" 64.It "\&165\ ``u'' \t166\ ``v'' \t167\ ``w'' \t170\ ``x'' \t171\ ``y''" 65.It "\&172\ ``z''" 66.El 67.Sh RETURN VALUES 68The 69.Fn islower 70function returns zero if the character tests false and 71returns non-zero if the character tests true. 72.Sh COMPATIBILITY 73The 74.Bx 4.4 75extension of accepting arguments outside of the range of the 76.Vt "unsigned char" 77type in locales with large character sets is considered obsolete 78and may not be supported in future releases. 79The 80.Fn iswlower 81function should be used instead. 82.Sh SEE ALSO 83.Xr ctype 3 , 84.Xr iswlower 3 , 85.Xr tolower 3 , 86.Xr ascii 7 87.Sh STANDARDS 88The 89.Fn islower 90function conforms to 91.St -isoC . 92