1.\" $OpenBSD: isspace.3,v 1.15 2022/09/11 06:38:10 jmc Exp $ 2.\" 3.\" Copyright (c) 1991 The Regents of the University of California. 4.\" Copyright (c) 2017 Ingo Schwarze <schwarze@openbsd.org> 5.\" All rights reserved. 6.\" 7.\" This code is derived from software contributed to Berkeley by 8.\" the American National Standards Committee X3, on Information 9.\" Processing Systems. 10.\" 11.\" Redistribution and use in source and binary forms, with or without 12.\" modification, are permitted provided that the following conditions 13.\" are met: 14.\" 1. Redistributions of source code must retain the above copyright 15.\" notice, this list of conditions and the following disclaimer. 16.\" 2. Redistributions in binary form must reproduce the above copyright 17.\" notice, this list of conditions and the following disclaimer in the 18.\" documentation and/or other materials provided with the distribution. 19.\" 3. Neither the name of the University nor the names of its contributors 20.\" may be used to endorse or promote products derived from this software 21.\" without specific prior written permission. 22.\" 23.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33.\" SUCH DAMAGE. 34.\" 35.Dd $Mdocdate: September 11 2022 $ 36.Dt ISSPACE 3 37.Os 38.Sh NAME 39.Nm isspace , 40.Nm isspace_l 41.Nd whitespace single-byte character test 42.Sh SYNOPSIS 43.In ctype.h 44.Ft int 45.Fn isspace "int c" 46.Ft int 47.Fn isspace_l "int c" "locale_t locale" 48.Sh DESCRIPTION 49The 50.Fn isspace 51and 52.Fn isspace_l 53functions test for whitespace characters. 54.Pp 55In the C locale, the complete list of whitespace characters is: 56.Pp 57.Bl -tag -width xxxxx -offset indent -compact 58.It Sq \0 59Space character. 60.It Li \ef 61Form feed. 62.It Li \en 63New-line. 64.It Li \er 65Carriage return. 66.It Li \et 67Horizontal tab. 68.It Li \ev 69And vertical tab. 70.El 71.Pp 72.Ox 73always uses the C locale for these functions, 74ignoring the global locale, the thread-specific locale, and the 75.Fa locale 76argument. 77.Sh RETURN VALUES 78These functions return zero if the character tests false or 79non-zero if the character tests true. 80.Sh ENVIRONMENT 81On systems supporting non-ASCII single-byte character encodings, 82these functions may return non-zero for additional characters, 83and the results of 84.Fn isspace 85may depend on the 86.Ev LC_CTYPE 87.Xr locale 1 . 88.Sh SEE ALSO 89.Xr isalnum 3 , 90.Xr isalpha 3 , 91.Xr isascii 3 , 92.Xr isblank 3 , 93.Xr iscntrl 3 , 94.Xr isdigit 3 , 95.Xr isgraph 3 , 96.Xr islower 3 , 97.Xr isprint 3 , 98.Xr ispunct 3 , 99.Xr isupper 3 , 100.Xr iswspace 3 , 101.Xr isxdigit 3 , 102.Xr stdio 3 , 103.Xr toascii 3 , 104.Xr tolower 3 , 105.Xr toupper 3 , 106.Xr ascii 7 107.Sh STANDARDS 108The 109.Fn isspace 110function conforms to 111.St -ansiC , 112and 113.Fn isspace_l 114to 115.St -p1003.1-2008 . 116.Sh HISTORY 117The 118.Fn isspace 119function first appeared in 120.At v7 , 121and 122.Fn isspace_l 123has been available since 124.Ox 6.2 . 125.Sh CAVEATS 126The argument 127.Fa c 128must be 129.Dv EOF 130or representable as an 131.Vt unsigned char ; 132otherwise, the result is undefined. 133