[TUHS] Reading UNIX V6: Does eash process has its own user structure, or all the processes share one copy of it?

[Hellwig Geisse]

On Tue, 2006-10-03 at 12:05 +0300, jigsaw wrote:
> First, I doubt whether all processes share one "u" or each process has
> its own "u".

Every process has its own u-area.
They have all at the same virtual kernel address,
but live in different physical locations.

> So isn't it saying that there's only one "u" in the core memory?

No. The running process' u-area is mapped into
the virtual address space before executing any
instructions of the process.

Hellwig