doug@s15:~$ cat cccc
this is file cccc.
doug@s15:~$ cat bbbb
this is file bbbb.

File Name to Append to: cccc

File Name to Append to: bbbb

doug@s15:~$ cat bbbb
this is file bbbb.
this is file cccc.

The notation for shortcuts is as follows: Control-key sequences are
 notated with a caret (^) symbol and can be entered either by using the
 Control (Ctrl) key or pressing the Escape (Esc) key twice.  Escape-key
 sequences are notated with the Meta (M-) symbol and can be entered using
 either the Esc, Alt, or Meta key depending on your keyboard setup.