Re: What's an annex? stratum?

[Michael Eager <eager@eagercon.com>]

Stan Shebs wrote:
> Michael Eager wrote:
>> Looking at target.c, I see some terms which are less
>> than clear:  annex and stratum.  Could someone tell me
>> what these mean?
> "Annex" is apparently an introduction of Andrew's from 2004, does kind 
> of look like an address space addition, although not clear that it's 
> fully implemented.

I'm assuming that the XML target description in the docs is similarly
incomplete and/or obsolete.

There seems to be a fair amount of cruft in the code, and
even more in the documentation.  Sigh.

> "Stratum" is an old concept, merely a way to talk about different levels 
> of the target stack. In practice, the stacking concept isn't as clean as 
> it must have seemed initially; sometimes you really want to run a target 
> op in a vector down in the stack, sometimes you want to replace a target 
> vector in the middle. So we introduce strata as a way to find a 
> mid-stack target vector of a desired type. First big block comment in 
> target.h goes into a bit more detail.

I read the comments, but it doesn't really say what the target stack is.
I see the enum for different strata, giving a hierarchy.

I can see that you might layer a core file on top of an executable
file, so that searching for a symbol/address was passed down until
you found the one which contained it.  But how does thread/process/
download fit into this picture?

-- 
Michael Eager	 eager@eagercon.com
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