                                                      Wimp_TextOp 3

    Finds a split point in a string in the current desktop font

On entry

    R0 = 3 (reason code)
    R1 = pointer to ctrl-terminated string
    R2 = distance into string (OS units)
    R3 = split character (-1 => none)
    
On exit

    R0 = pointer to split point in string
    R1-R3 preserved


                                                      Wimp_TextOp 4

    Truncates a string in the current desktop font if necessary

On entry

    R0 = 4 (reason code)
    R1 = pointer to ctrl-terminated string
    R2 = pointer to buffer to receive modified string (ellipsis or '...' may
         be added, depending upon alphabet and font)
    R3 = size of buffer, bytes
    R4 = maximum width of string (OS units)
    
On exit

    R0 = size of buffer needed
    R1-R4 preserved
