FTP LIST command responses

I'm trying to write an FTP server in Java and have the basic functionality down, but I can't开发者_如何学编程 figure out or find any information on the LIST command.

LIST -a sends a list of files like

drwxrwxrwx 1 stefan stefan             0 Jan  1  1970 personaluploads
-rwxrwxrwx 1 stefan stefan             0 Jan  1  1970 serverflags.txt
-rwxrwxrwx 1 stefan stefan             0 Jan  1  1970 serveroptions.txt
-rwxrwxrwx 1 stefan stefan             0 Jan  1  1970 levels_npcserver.txt

over the data connection.

What am I supposed to return with just LIST? Do I send it over the data connection or the control connection?

Thanks for the help.

See RFC 959 - File Transfer Protocol. It has all the info you need.

LIST (LIST)

            This command causes a list to be sent from the server to the
            passive DTP.  If the pathname specifies a directory or other
            group of files, the server should transfer a list of files
            in the specified directory.  If the pathname specifies a
            file then the server should send current information on the
            file.  A null argument implies the user's current working or
            default directory.  The data transfer is over the data
            connection in type ASCII or type EBCDIC.  (The user must
            ensure that the TYPE is appropriately ASCII or EBCDIC).
            Since the information on a file may vary widely from system
            to system, this information may be hard to use automatically
            in a program, but may be quite useful to a human user.