[FreeVMS] FreeVMS

[BERTRAND Joël]

Roar Thronæs wrote:
> On Thu, Jun 13, 2013 at 07:43:37AM +0200, BERTRAND Joël wrote:
>>
>> FreeVMS project was created a long time ago. First kernels (until 0.3)
>> were derivated from Linux kernel (2.4.15 if I remember) and were
>> monolithic. These kernels were bootable but not easely maintenable.
>
> Yes, I know, but it was small enough with few hardware drivers,
> since qemu supported only a few.

	Right, but we need to think about future and portability.

> I would consider it small enough to be further changable/convertible/
> transformable, to something non-monolithic, but gave it low priority.
> I gave it low priority, because:
>
> For a user who is downloading an image and running it with qemu,
> does not see whether it is monolithic or not.
> The user will only notice features like logicals, type, dir, show system etc.
> For developers of userland utilities/libraries and parts of the kernel,
> it would not matter either whether the kernel was monolithic or not.

	Maybe, but I think that stability and maintainability are both crucial 
to have new developers.

>> 0.4 is rewritten from scratch on a L4 (like Hurd is written on a Mach
>> kernel or MacOS X on NVU). L4 is choosen because it deos not contains
>> unixism. It boots, it contains first memory management subroutines, but
>> pager is missing.
>
> This will be a bit harder than transforming the 0.3 kernel
> (but probably a more interesting/rewarding learning process).
> It will be interesting to see how ASTs and IPLs will be implemented now.
>
> Will you actually write everything from scratch?
> I integrated/took a lot from various places.

	No. You have done some years ago a very huge work. All code you have 
written will be reused.

> (Some libraries/rtl/starlet and userland ODS-2/RMS from the very first
> FreeVMS project, if my memory serves me right.
> DFU from DEC with open (enough?) source.
> The CMUIP TCP/IP stack.
> Something for DCL and EDT from Ozone from www.o3one.org.
> Probably more.)

	Regards,

	JKB