Using rlwrap

RLWRAP is a program for Linux and Unix-like operating systems, and it can also be installed in Windows using WSL.

Using rlwrap with a telnet client when playing Galactic Empire gives the user several advantages:

• Full arrow key editing support: use the left and right arrow keys to edit commands as they're being typed
• Command history: use the up and down arrow keys to scroll through a history of commands
• Commands aren't sent to the server until enter is pressed: output is not paused as the user is typing

Some BBS systems may have trouble initializing ANSI color support when using rlwrap, YMMV. (TO DO: possible to fix this?)

Basic use

Install rlwrap if needed; look online for instructions for your particular operating system.

Run your telnet client with rlwrap:

rlwrap -a -A telnet example.com port

where "example.com" is the BBS server hosting Galactic Empire, and "port" is the port number if required. (-a is required for telnet, -A enables enhanced ANSI color support.)

Once you're in the game, you can play as normal. The screen will continue to scroll while you're typing commands. If you make a mistake as you're typing, you can now use the left and right arrow keys to edit the line. You can also press up arrow to pull up the last command you entered, which can be very helpful for executing repetitive commands.

Password masking

By default, rlwrap will display your BBS password on the screen as you're typing it in, and save it in the command history. If this is a concern, add your BBS's password prompt after the -a option like this:

rlwrap -aPassword: -A telnet example.com port

This will exclude any "Password:" prompt from rlwrap's processing.

If your BBS's password prompt has ANSI color codes, this becomes a little more complicated. To find the codes, use tee:

telnet example.com port | tee color_test

Log in to your BBS, and log out. Then open the color_test file using vi or nano and look for the password prompt.

Simple color filter

If you've ever noticed Galactic Empire's output getting dimmer as you play, it's because the game starts using ANSI bold text (code 1) but the output from certain commands (mainly HELP commands) often resets the screen to normal text (code 0). Here is a simple filter based off rlwrap's "scrub_prompt" filter that resets all prompts to bold text:

#! /usr/bin/perl

# filter for Galactic Empire

use lib ($ENV{RLWRAP_FILTERDIR} or ".");

use RlwrapFilter;

use strict;

my $filter = new RlwrapFilter;

my $name = $filter -> name;

$filter -> help_text("Usage: rlwrap -z '$name [-o]' <command>\n".

                     "Galactic Empire rlwrap filter\n"

);

$filter -> prompt_handler(\&scrub);

$filter -> run;

sub scrub {

    my ($dirty) = @_;

    my $clean = $dirty;

    $clean =~ s/^>/\x1b\[1;37m>/g; # change prompts to white bold

    return $clean;

}

Save this file as "ge_filter" (or whatever you like) and enter chmod +x ge_filter to make it executable. Use this filter with rlwrap's -z option:

rlwrap -aPassword: -A -z ./ge_filter telnet example.com port

License

rlwrap (and scrub_prompt) are licensed under the GNU GPL version 2.