[DGD] MODE_NOECHO newline

[Raymond Jennings]

You should be aware that telnet mode in DGD does some automatic processing
of output, and that includes line endings.

I got burned by this once when I tried to use telnet mode to handle HTTP
connections.

My advice:  Use binary connections for everything.

Now I am curious what you mean about noecho.  Do you mean the telnet option
WILL/WONT ECHO?

As far as I know, how it works is as follows:

Normally, the connection is labelled by DGD as "echo".

In the telnet layer, this equates, ironically, to NO ECHO, which means the
server is telling the client that it won't do any echoing, which in turn
tells the client to do that itself.

When DGD sets the connection to "noecho", the server actually sends WILL
ECHO and dishonestly tells the client that it will do echoing, but then
doesn't actually echo, so the client sends keystrokes without echoing them
locally, and they never get echoed by the server either, ergo things like
passwords and whatnot never show up on the client's terminal because
neither side echoed them.

Since a "noecho" connection has the server dishonestly telling the client
that it doesn't need to echo locally, this also includes the final newline
the client sends when the user hits the Enter key after typing the password.

What you have to do is echo the newline manually server-side.

The example of the password first has the server send a password prompt:

Password:

And then the cursor sits after the colon while the user types the password
and hits enter.  However, since local echoing has been turned off by server
request, it never jumps to the next line unless the server spits out a
newline of its own.

I hope this explains everything, I was mostly rambling for the sake of the
list in general.

On Sat, Jul 30, 2016 at 1:49 PM, Blain <blain20 at gmail.com> wrote:

> When I switch to noecho mode, the lines following a newline are severely
> indented.  To fix it, I have to replace \n with \r\n before sending it to
> the user.  This doesn't happen in echo mode.  Any ideas on where to start
> looking?  Kernel code and my code seem fine so far.
> ____________________________________________
> https://mail.dworkin.nl/mailman/listinfo/dgd