ccollate ?-local? string1 string2
          This command compares two strings.  If  returns  -1  if
          string1 is less than string2, 0 if they are equal and 1
          if string1 is greater than string2.

          If  -local  is  specified,  the  strings  are  compared
          according  to  the collation environment of the current
          locale.

          This command does not work with binary or UTF data.

          This command is provided by Extended Tcl.