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WCWIDTH(3) FreeBSD Library Functions Manual WCWIDTH(3)
NAME
wcwidth - number of column positions of a wide-character code
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <wchar.h>
int
wcwidth(wchar_t wc);
DESCRIPTION
The wcwidth() function determines the number of column positions required
to display the wide character wc.
RETURN VALUES
The wcwidth() function returns 0 if the wc argument is a null wide
character (L'\0'), -1 if wc is not printable, otherwise it returns the
number of column positions the character occupies.
EXAMPLES
This code fragment reads text from standard input and breaks lines that
are more than 20 column positions wide, similar to the fold(1) utility:
wint_t ch;
int column, w;
column = 0;
while ((ch = getwchar()) != WEOF) {
w = wcwidth(ch);
if (w > 0 && column + w >= 20) {
putwchar(L'\n');
column = 0;
}
putwchar(ch);
if (ch == L'\n')
column = 0;
else if (w > 0)
column += w;
}
SEE ALSO
iswprint(3), wcswidth(3)
STANDARDS
The wcwidth() function conforms to IEEE Std 1003.1-2001 ("POSIX.1").
FreeBSD 14.0-RELEASE-p11 August 17, 2004 FreeBSD 14.0-RELEASE-p11