freebsd-dev/lib/libc/locale/wcwidth.3
Tom Rhodes 1bdc6fddbf /me kicks cvs update
Revert previous commit, tjr already fixed it and I was too stupid to
notice this fact.

Approved by:	re (to avoid failing cvs ci)
2004-08-17 04:56:03 +00:00

88 lines
2.4 KiB
Groff

.\" Copyright (c) 2002 Tim J. Robbins
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\" notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\" notice, this list of conditions and the following disclaimer in the
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.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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.\" $FreeBSD$
.\"
.Dd August 17, 2004
.Dt WCWIDTH 3
.Os
.Sh NAME
.Nm wcwidth
.Nd "number of column positions of a wide-character code"
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In wchar.h
.Ft int
.Fn wcwidth "wchar_t wc"
.Sh DESCRIPTION
The
.Fn wcwidth
function determines the number of column positions required to
display the wide character
.Fa wc .
.Sh RETURN VALUES
The
.Fn wcwidth
function returns 0 if the
.Fa wc
argument is a null wide character (L'\e0'),
\-1 if
.Fa wc
is not printable,
otherwise it returns the number of column positions the
character occupies.
.Sh EXAMPLES
This code fragment reads text from standard input and
breaks lines that are more than 20 column positions wide,
similar to the
.Xr fold 1
utility:
.Bd -literal -offset indent
wint_t ch;
int column, w;
column = 0;
while ((ch = getwchar()) != WEOF) {
w = wcwidth(ch);
if (w > 0 && column + w >= 20) {
putwchar(L'\en');
column = 0;
}
putwchar(ch);
if (ch == L'\en')
column = 0;
else if (w > 0)
column += w;
}
.Ed
.Sh SEE ALSO
.Xr iswprint 3 ,
.Xr wcswidth 3
.Sh STANDARDS
The
.Fn wcwidth
function conforms to
.St -p1003.1-2001 .