3.31: addm/extending the const-var architecture:
. what I'm calling the constant-var architecture
makes use of hardware isolation mechanisms
by safely dividing the system into
constant code, and variable data .
. there is another segment to consider:
. what's variable across process instances
can be constant during execution .
# special permissions:
. the implied permission is that the
data in the process belongs to that process .
. the activation record's resource display
is an example of special permissions:
the process has permission only to
read the resource display, not write to it;
but the supervisor can modify it .