wcwidth(3) - NetBSD Manual Pages

WCWIDTH(3)              NetBSD 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 nul wide charac-
     ter (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'').

NetBSD 9.0                      August 17, 2004                     NetBSD 9.0