Base Operating System and Extensions Technical Reference, Volume 2 wcwidth Subroutine Purpose Determines the display width of wide characters. The wcwidth subroutine determines the number of display columns to be occupied by the wide character specified by the WC parameter.
Parameters WC Specifies a wide character.
The wcwidth subroutine returns the number of display columns to be occupied by the WC parameter. If the WC parameter is a wide character null, a value of 0 is returned. If the WC parameter points to an unusable wide character code, -1 is returned. Invalid wide character in wc. The wcswidth subroutine.