[cap-talk] MinorFS presentation.

[Rob Meijer]

The following link is a presentation on MinorFS.

http://polacanthus.net/MinorFS-nobob.pdf

The original presentation has a picture of Bob the builder
on all slides with the caption "Shared mutable state, can we fix it?",
that I removed for copyright reasons, it makes the slides a bit less
colorful, but I trust all of you have a sufficiently colorful imagination
to imagine bob the builder back into those slides yourselves ;-)

I borrowed the solitaire example from Alan Karp, hope that's alright.

The presentation tries to show that the problem with filesystem access
for $HOME and $TEMP is in fact the same problem as the problem that OO
tried to solve, and that dependency injection and object capability
languages like E finaly solved in the software development realm.
That is the problem with shared mutable state in its many forms ranging
from global variables to explicitly shared references.

Than it goes on to show how AppArmor, Fuse and MinorFS put down a
foundation for solving it in filesystem access using the same set of
principles that OO and OC use.

Finally it graps back on the e-language and states that combining E its
persistence facility with MinorFs allows to lay down a stack that uses
these same principles at multiple levels.

It concludes by showing a fictional example, showing the total number of
lines that should be marked as 'trusted' powerful lines of code using non
safe languages on a system with a global (per user) $HOME and $TEMP
compared to the same system using MinorFS provided private $HOME and $TEMP
and using a (persistent) ocap language for a limited number of 'trusted'
powerful programs.