Baslinux mailing list

[Nguyen The Luan <luannt AT atvn.com.vn>]

Title: RE: BasLinux Digest, Vol 11, Issue 28

> Certain daemons that could be critical to system function are actually set
> up as "virtual" users, aren't they (e.g., bin, sync, lp on the system I'm
> sitting at now)?  If so, I'd think the system might not run at all in
> single-user mode - assuming that single-user means no other users, real or
> virtual, can be logged in and running at the same time.  I don't know from
> experience that: 1) all such virtual user daemons are critical to system
> operation; 2) running in single-user mode prevents such virtual users from
> operating - but those are some possible obstacles to trying to run Linux
> in single-user mode.

> James

The reason why I want to do that is:

I'm writing lowlevel softwares (work on linux) for my system.
My softwares are used to test/control hardware devices (SRAM, FLASH, FPGA, LEDs,...).
I need to write my tasks in the way that they can communicate with users.
But I can't let my user tasks to access directly to memory map of such hw devices.
So I have to write 2 tasks for each application. One in user space and the other in kernel space. User space task get information from users and send the information to kernel task, kernel task work on hardware and then send results to user task, then user task show result to users.

The model is rather complicated, and it takes me long time to train my programmers.
So I think that If I can make user space tasks can access to hardware (system resources) like kernel task can do,
then my software model will be simpler (only one task for each application), easier to develop, debug, and it can run faster.

I control all of the tasks in my system, so I don't care about some user tasks can harm my system.
Please give me some ideas.

Best regards.

Nguyen.