ENiGMA½ supports a variety of methods for interacting with doors not limited to:
*`abracadabra` module: Standard in/out (stdio) capture or temporary socket server that can be used with [DOSEMU](http://www.dosemu.org/), [DOSBox](http://www.dosbox.com/), [QEMU](http://wiki.qemu.org/Main_Page), etc.
*`bbs_link` module for interaction with [BBSLink](http://www.bbslink.net/)
## The abracadabra Module
The `abracadabra` module provides a generic and flexible solution for many door types. Through this module you can execute native processes & scripts directly, and process I/O through stdio or a temporary TCP server.
The `abracadabra``config` block can contain the following:
*`name`: Used as a key for tracking number of clients using a particular door
*`dropFileType`: Specifies the type of drop file to generate (See table below)
*`cmd`: Path to executable to launch
*`args`: Array of argument(s) to pass to `cmd`. See below for information on variables that can be used here.
*`nodeMax`: Max number of nodes that can access this door at once. Uses `name` as a mapping key
*`tooManyArt`: Art file spec to display if too many instances are already in use
*`io`: Where to process I/O. Can be `stdio` or `socket`
*`{srvPort}`: Tempoary server port when `io` is `socket`
### DOSEMU with abracadabra
[DOSEMU](http://www.dosemu.org/) can provide a good solution for running legacy DOS doors when running on Linux systems. For this, we will a virtual serial port (COM1) that communicates with stdio.
As an example, here are the steps for setting up Pimp Wars:
First, create a `dosemu.conf` file with the following contents:
```
$_cpu = "80486"
$_cpu_emu = "vm86"
$_external_char_set = "utf8"
$_internal_char_set = "cp437"
$_term_updfreq = (8)
$_layout = "us"
$_rawkeyboard = (0)
$_com1 = "virtual"
```
The line `$_com1 = "virtual"` tells DOSEMU to use `stdio` as a virtual serial port on COM1.
Next, we create a virtual **X** drive for Pimp Wars to live such as `/enigma-bbs/DOS/X/PW` and map it with a custom `autoexec.bat` file within DOSEMU:
```
@echo off
path d:\bin;d:\gnu;d:\dosemu
set TEMP=c:\tmp
prompt $P$G
REM http://www.pcmicro.com/bnu/
C:\BNU\BNU.COM /L0:57600,8N1 /F
lredir.com x: linux\fs\enigma-bbs\DOS\X
unix -e
```
Note that we also have the [BNU](http://www.pcmicro.com/bnu/) FOSSIL driver installed at `C:\BNU\\`. Another option would be to install this to X: somewhere as well.
Finally, let's create a `menu.hjson` entry to launch the game:
[QEMU](http://wiki.qemu.org/Main_Page) provides a robust, cross platform solution for launching doors under many platforms (likely anwywhere Node.js is supported and ENiGMA½ can run). Note however that there is an important and major caveat: **Multiple instances of a particular door/OS image should not be run at once!** Being more flexible means being a bit more complex. Let's look at an example for running L.O.R.D. under a UNIX like system such as Linux or FreeBSD.
Basically we'll be creating a bootstrap shell script that generates a temporary node specific `go.bat` to launch our door. This will be called from `autoexec.bat` within our QEMU FreeDOS partition.
#### Step 1: Create a FreeDOS image
[FreeDOS](http://www.freedos.org/) is a free mostly MS-DOS compatible DOS package that works well for running 16bit doors. Follow the [QEMU/FreeDOS](https://en.wikibooks.org/wiki/QEMU/FreeDOS) guide for creating an `freedos_c.img`. This will contain FreeDOS itself and installed BBS doors.
After this is complete, copy LORD to C:\DOORS\LORD within FreeDOS. An easy way to tranfer files from host to DOS is to use QEMU's vfat as a drive. For example:
Note the `qemu-system-i386` line. We're telling QEMU to launch and use localtime for the clock, create a character device that connects to our temporary server port on localhost and map that to a serial device. The `-hdb` entry will represent the D: drive where our drop file is generated, while `-hdc` is the path that `GO.BAT` is generated in (`E:\GO.BAT`). Finally we specify `-nographic` to run headless.
