wcswidth(3C)

wcswidth -- determine the number of column positions for a wide character string

Synopsis

   #include <wchar.h>
   
   int wcswidth(const wchar_t *pwcs, size_t n);

Description

wcswidth determines the number of column printing positions needed for up to n wide characters in the wide string pwcs. Fewer than n wide characters will be processed only if a null wide character is encountered before n wide characters in pwcs.

Return values

wcswidth returns either zero if pwcs is pointing to a null wide character code, or the number of column positions occupied by the wide character string pointed to by pwcs. wcswidth returns -1 if any wide character code in the wide character string pointed to by pwcs is not a printable wide character.

Examples

This example function, when passed a wide character string, calculates the number of column positions required and prints a diagnostic message.

   #include <wchar.h>
   #include <stdio.h>
   
   . . .
   

   int
   print_width(const wchar_t *pwcs)
   {
   	int width;
   	size_t len;
   

   	len = wcslen(pwcs);
   	if (len > 0)  {
   		width = wcswidth (pwcs, len);
   		if (width == -1)
   		   (void) printf("non printable character\n");
   		else
   		   (void) printf("Wide string width=%d\n",width);
   		return (1);
   	}
   

   	(void) printf("zero length wide character string\n");
   	return (0);
   

   }

References

wchar(5), wcwidth(3C)