DEL L - (PF4)

 Deletes text from the cursor position to the end of the current line, including
 the line terminator.  If the cursor is positioned at the beginning of a line,
 the entire line is deleted.  The deleted text is saved in the delete line
 buffer.

 UND L - (GOLD PF4)

 Inserts the contents of the delete line buffer directly to the left of the
 cursor.