Question

I want to download and try an Open-Source OS (Emulation) written in Java. So, I searched and download the, arguably, most famous one I found, which was NACHOS 5.0j.

I have just installed a fresh Ubuntu 10.04 LTS and installed the open-JDK 1.6 through apt-get and then installed eclipse in a similar manner.

After following the readme in NACHOS, I fired terminal, and used gmake (make), and got a bunch of errors and warnings. The one that’s bothering me the most is:

as of release 1.4, 'assert' is a keyword, and may not be used as an identifier 
(use -source 1.3 or lower to use 'assert' as an identifier)
Debug.assert(isReadyForApply);

Problem is, I tried downloading another open-source OS called JX, and had a similar problem.

Any help in this issue is appreciated! Any other ideas on where to start learning about operating systems and Java is even more appreciated! (But something practical.)

Answer 1

I found following information from web, basically, you should use java 1.3.1. it is open source, and you can modify the source code to make it run under JDK1.6 if you like.

The Java version of Nachos only
supports Java 1.3.1, as the security
manager and set of reserved keywords
has changed in later versions.
Instructional machines already have
1.3.1 installed. For remote users, you can download 1.3.1 here:
http://java.sun.com/j2se/1.3/download.html
. If you are curious to see what
version of java you are using you can
run the following command “java
-version”. We cannot stress strongly enough that you should not use java
1.4 or java 1.5. You might run into transient errors that will not show up
as warnings or errors during compile
time.