value.i4.v = inbox(boxrow.i2.r, nrows.i2.r, boxcol.i2.r, ncols.i2.r)
value.i4.v = inbox_c(boxrow.i4.v, nrows.i4.v, boxcol.i4.v, ncols.i4.v)
'inbox' is a logical function which will return .TRUE. if the color
TV cursor was in a specifed box the last time the intype routine
was called. The box is specified by a starting row (BOXROW), a
number of rows (NROWS), a starting column (BOXCOL) and a number of
columns (NCOLS). The intype_put_rowcol routine can be used to
fake the INTYPE cursor location.