Icaros Desktop has been focusing on native installations for 10 year. It can now be successfully installed on many different configuration and it supports a quite good variety of expansion cards. However, we’ve got many requests for a ‘hosted’ release that could run on top of a Linux or even Windows installation. A question, however, immediately rose: why should anyone use AROS software on a Windows or Linux system, when they already had all the programs these OSes offer? The question, however, is wrong. The correct question is: “I have all Linux/Windows programs available outside of  Icaros Desktop: what may I do with them?”

The answer is HostBridge

HostBridge allows starting host applications from Icaros Desktop. It’s neither a emulation layer, nor a complex networking tool, but just something that asks the host operating system to run something else for you. You won’t get Linux or Windows applications appear on AROS workbench, nor their window theme will follow AROS one, but at least you will be able to:

  • Start your host applications from the AROS shell, like any other AROS program or command;
  • Import an icon from Win32 programs or choose a icon in .info or .png format;
  • Add "imported" applications to AmiStart and any other AROS dock or launcher;
  • Use Icaros paths to open your files from imported application, for instance: "photoshop sys:Temp/MyPhoto.png";
  • Launch scripts on the host system to manage it;
  • Once everything has been correctly configured, use Icaros Desktop as alternative GUI for your host system 

How it works

HostBridge works in a very simple way. It runs a little daemon on the host operating system, waiting for a command to execute. When Icaros Desktop needs to run a host application, HostBridge tells the daemon what to do. This daemon is platform specific and it’s copied by Icaros hosted installation script in your S directory. It starts in the background when you launch Icaros Desktop (so, for security reasons, please remember to run Icaros as a limited, no-administrative user).

On the guest environment, you’ll find a “Hosted” drawer in Sys:System one. While on native installations this drawer is empty, in hosted ones it includes HostBridge’s main scripts and data files. HostBridge scripts are executable and automatically added to PATH, so they can be invoked anywhere from the AROS shell. Commands like hbrun and hbscript let you start programs and scripts on your host system using paths in AmigaDOS format, for instance
hbrun WdC:Windows/System32/compmgmt.msc
will run host's Computer Manager console on a Windows system. The hbscript command, instead, is thought to run shell scripts like the sh (on Linux) and powershell -file (on Windows) commands.

On Windows, hbrun can open .exe, .bat, .com and .msc files

Integrating programs

The best part of hostbridge, however, still has to come: Linux and Windows applications can be "integrated", meaning that Icaros Desktop will be able to start and pass to them a file name to open. The hbadd wizard allows to create a launch script for them. Once you'll have 'hbadded' an app, it will be immediately available from AROS shell and GUI (Wanderer/Magellan).

Integrated applications launch scripts are stored in SYS:System/Hosted/HostApp

Let’s assume you’ve already integrated Adobe ImageReady into Hostbridge, and that you need this program to modify a picture inside your MyWorkspace/Pictures drawer (that’s an example: the image can be stored in any part of the filesystem except, for obvious reasons, the RAM drive). If you open the same file directly from Windows, you must remember that the “Pictures” drawer is stored on the drive you’ve installed Icaros Desktop on, in a subfolder of the MyWorkspace directory. But if you simply run an AROS shell from the Pictures directory, all you have to do is entering…

imageready <filename>

You can even set a Linux or Windows application as default tool to open a single file or a whole kind of objects, but this is well explained in Icaros Desktop manual. So no need to repeat here.