procedure SInsert(var t: packed array [tlow..thigh: integer] of char;
                 s: packed array [slow..shigh: integer] of char;
                 Start: integer
  	);
   EXTERNAL;
{*USER*
 Insert string "s" into string "t", starting at position "start". Characters
of t are moved to the right of as needed. The combination of "S" and "T"
may be larger than the size of "t", in which case "t" will be truncated
- including part of "s", if this is required.
Values of Start which would produce a non-contiguous string result in
a fatal error.
}