Re: Ada OS

[anon@anon.org (anon)]

The problem is the scope of the project. Most people who hear about 
an "Ada OS" they think it will be similar to "Microsoft Windows" 
or Mac, Linux, Posix, Unix design, that's a big job. The following 
will give you some idea, but know that I am skipping a lot of steps 
between each of the stages.

Stage 0: A plan or purpose for the OS. Microsoft's or the Unix type 
of OS are a general purpose. But you can have specific version such 
as Real-Time OS. This needs to be written in detail before any other 
stages are started. And writing documentation is dull, most people 
stop before finishing this stage. 

        NOTE: A simple design may take a week something like 
              Windows design could take a year. 

        NOTE: Where do you stop using Ada only coding and 
              allow projects in other languages. Or do you. 

Stage 1: create a team of programmers. A simple kernel may require one 
programmer, but a DOS like OS will take a team of 10 to 25 programmers 
or more. Plus, some of these programmers may leave the project before 
the OS is created, so, you have to have others available. Then you have 
to deal with the in fighting. Most will want to create the kernel, but 
how many will want to create the first command line simple text editor 
like 'e' or a full blown 'vi'.

Stage 2: Creating the kernel initially based on Stage 0 design. 
Plus, if the kernel is for multiple classes of cpus (IA_32, IA_32_64, 
IA_64, others) then you will need a kernel for each class. At the 
movement Ada does not contain conditional compiling statements. And 
I hope that it never does.

        NOTE: Now most Ada OS's stop here. That's because the 
              author's reason for the OS is done or the author 
              has no more time for their project.
              But the kernel is not an OS, it just the 
              beginning or core of an OS.


Stage 3: Is the Ada compiler and its libraries for this kernel. 

        NOTE: Here also multiple compilers are needed because 
              Ada does not have conditional compiling. 


STAGE NOTE: Starting with Stage Four the system should be hardware 
independent enough to allow standardize applications. Only need to 
compile source for each cpu class.

Stage 4: OS support applications. Such as hardware configuration and 
simple command shell.  These hardware applications, sets up the 
networks or Time and Date functions, etc. This also includes the File 
Systems support applications such as FDISK and FORMAT.

        Note: At this point the OS should have the functionability 
              of a DOS. With one major application the Ada 
              compiler system. 

        Note: In today environment, DOS in not really useable. 
              So, the OS will need a GUI, a browser for the 
              internet, ect.

Stage 5: GUI and the windows like applications. But this requires the 
kernel has some kind of graphic video driver for each type of video 
card supported. And the compiler having a graphics library packages.  

        Note: Linux uses X-Windows, there are a couple of
              GUIs interfaces out there like KDE or GOME to 
              name two. And these took years to write with each 
              having their own applications. And each project 
              is not finished either.

And the list goes on!

TIME TABLE: Except for the simple kernel which a single student 
programmer might write within a semester. Each Stage may require a 
year or more. So, an Ada only type of OS might be 5 years in the 
future. 

FINAL WORD: In 5 year, how many people will want to use Ada or an 
Ada OS. Plus, the time required for upgrading the system because of 
hardware. So, most programmer just do not want to spend that amount 
of time on a non-paying project that most people will never use. 

FINAL NOTE: Linux started off as a free replacement to the high 
dollar UNIX OS. That gave the initial programmers a reason to join 
and stay with the Linux team. Later came other reasons.

FINAL NOTE: This is not all but it does give you an idea just how 
big this project is.

In <bfc38822-0a92-47fd-ad74-853ea6b66013@v4g2000hsf.googlegroups.com>, Lucretia <lucretia9@lycos.co.uk> writes:
>On Nov 22, 10:13 am, Peter Hermann <ica...@lucky.ihr.uni-stuttgart.de>
>wrote:
>
>> >From: "Randy Brukardt" <ra...@rrsoftware.com>
>> >Newsgroups: comp.lang.ada
>> >Subject: Re: ada compiler?
>> >Date: Fri, 16 Nov 2007 19:37:27 -0600
>> >able to make an OS mechanism work "right".. (My holy grail would be an
>> >all-Ada system, but I realize that is not practical in the real world for
>> >the vast majority of applications - including mine.)
>
>Thought it was this bit. I wonder why he thinks it's not all that
>viable.
>
>Luke.