WCWIDTH(3) | Library Functions Manual | WCWIDTH(3) |
wcwidth
, wcwidth_l
— number of column positions of a wide-character
code
Standard C Library (libc, -lc)
#include
<wchar.h>
int
wcwidth
(wchar_t wc);
#include <wchar.h>
#include <xlocale.h>
int
wcwidth_l
(wchar_t wc,
locale_t loc);
The
wcwidth
()
function determines the number of column positions required to display the
wide character wc.
Although the
wcwidth
()
function uses the current locale, the
wcwidth_l
()
function may be passed a locale directly. See
xlocale(3) for more information.
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.
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; }
The wcwidth
() function conforms to
IEEE Std 1003.1-2001 (“POSIX.1”).
August 17, 2004 | macOS 14.6 |