Assigns a text stream to a frame to be used to fill any unused spaces in that frame. If the filler stream is not used the unused spaces will remain blank. A filler stream automatically restarts when its end is reached but is skipped when PTC ALD encounters a paragraph that is too large to fit in any of the available spaces.

The use of a frame filler stream is only permitted when in Normal Fill mode, not in Fill Top or Fill Cols modes. For further information, see tfcol.