DOpE is an acronym for 'Desktop Operating Environment'. It is a windowing system for the real-time operating system DROPS, which is devloped at the OS-Group in Dresden. DROPS is based on the microkernel Fiasco (an implementation of the L4 API). DOpE provides the real-time facilities of DROPS at the user interface level. So what does that mean? Real-time? A real-time operating system assures that the processing time demands of certain tasks get satisfied. There are several application areas where such guaranties are needed (or nice to have), such as burning a CDR, multimedia streaming or control systems. A basic property of such tasks is their predicability of their behaviour. They normaly do their tasks periodically by consuming a fixed amount of processing time to effect a fixed amount of data. When interactivity comes into play (this is the case for DOpE), things get tricky because the behaviour of the user is not predicable. Subordinating the user lower than concurrently running real-time tasks is not sufficient since a user has its own demands (reponse latency, ergonomy). DOpE tries to solve this conflict. If you want to know how - I recommend reading my diploma thesis about this topic. You can find it here:

File section:

files/DOpE/documents/index.html

There is also a technical report that presents the overall architecture of DOpE and highlights the mechanisms used for its real-time capability.

Yes, it is available via the OS Groups's remote Subversion repository under the terms of the GNU General Public Licence. For more information about the GNU General Public Licence visit the official GNU website:

GNU Website:

http://www.gnu.org/licenses/

You will need the L4 Environment and DICE to build DOpE. These packages are also available at our repository:

OS Group SVN Repository:

http://svn.tudos.org/repos/tudos/trunk/

To check out only DOpE from the repository:

$ svn checkout -N http://svn.tudos.org/repos/tudos/trunk/l4/pkg/dope

If you want to build and use DOpE as part of the L4 Environment, you should check out the required packages from the repository by the following steps:

$ svn checkout -N http://svn.tudos.org/repos/tudos/trunk tudos $ cd tudos $ ./repomgr co l4env $ ./repomgr co dice $ svn up l4/pkg/dope

The DOpE package will then be located at l4/pkg/dope. More information about the other needed components are available at the following www-sites:

L4/Fiasco Microkernel:

http://os.inf.tu-dresden.de/fiasco/

L4 Environment:

http://os.inf.tu-dresden.de/l4env/

DICE IDL compiler:

http://os.inf.tu-dresden.de/dice/