.\"	$OpenBSD: isspace.3,v 1.10 2007/05/31 19:19:28 jmc Exp $
.\"
.\" Copyright (c) 1991 The Regents of the University of California.
.\" All rights reserved.
.\"
.\" This code is derived from software contributed to Berkeley by
.\" the American National Standards Committee X3, on Information
.\" Processing Systems.
.\"
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.\" modification, are permitted provided that the following conditions
.\" are met:
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.\"    may be used to endorse or promote products derived from this software
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.Dd $Mdocdate: May 31 2007 $
.Dt ISSPACE 3
.Os
.Sh NAME
.Nm isspace
.Nd whitespace character test
.Sh SYNOPSIS
.Fd #include <ctype.h>
.Ft int
.Fn isspace "int c"
.Sh DESCRIPTION
The
.Fn isspace
function tests for the standard whitespace characters
.\" or for any
.\" of an implementation-defined set of characters
for which
.Xr isalnum 3
is false.
The standard whitespace characters are the following:
.Pp
.Bl -tag -width xxxxx -offset indent -compact
.It Sq \0
Space character.
.It Li \ef
Form feed.
.It Li \en
New-line.
.It Li \er
Carriage return.
.It Li \et
Horizontal tab.
.It Li \ev
And vertical tab.
.El
.Pp
In the C locale,
.Fn isspace
returns true only for the standard whitespace characters.
.Sh RETURN VALUES
The
.Fn isspace
macro returns zero if the character tests false or
non-zero if the character tests true.
.Sh SEE ALSO
.Xr isalnum 3 ,
.Xr isalpha 3 ,
.Xr isascii 3 ,
.Xr isblank 3 ,
.Xr iscntrl 3 ,
.Xr isdigit 3 ,
.Xr isgraph 3 ,
.Xr islower 3 ,
.Xr isprint 3 ,
.Xr ispunct 3 ,
.Xr isupper 3 ,
.Xr isxdigit 3 ,
.Xr stdio 3 ,
.Xr toascii 3 ,
.Xr tolower 3 ,
.Xr toupper 3 ,
.Xr ascii 7
.Sh STANDARDS
The
.Fn isspace
function conforms to
.St -ansiC .
.Sh CAVEATS
The argument to
.Fn isspace
must be
.Dv EOF
or representable as an
.Li unsigned char ;
otherwise, the result is undefined.