Function            box - draw a box

  Syntax              int box(int left, int top, int right, int bottom,
                              char frame[]);

  Prototype in        video.h

  Remarks             draws a box via gotohv(), horiz_line(), putk() and
                      vert_line() (all use INTerrupts). Also, frame must
                      be have at least 9 elements (char frame[9]). The
                      box characters are frame[0] (top left) to frame[7]
                      (left wall), going clockwise. If frame[8] != '\0'
                      the box is filled with it.

  Return value        returns zero upon succesful completion, -1 if the
                      coordinates given are not large enough for a box.

  See also            global variables
                      boxwindow(), gotohv(), horiz_line(), putk(),
                      vert_line()

  Example             #include <video.h>

                      main()
                      {
                           char framebox[9] = "abcdefghi";

                           box(1,1,7,4,framebox);
                      }

  Program output      abbbbbc
                      hiiiiid
                      hiiiiid
                      gfffffe