[igodard]

The biggest problem with caps and legacy apps is not the semantics - a caps systems can emulate POSIX with no problem. The problem is the data representation: you can't fit a capability into a pointer, so all the data layouts change. Sadly, there are tons of C programs that make rash assumptions about data layout, and they would all break.

The guys are Cambridge have running caps systems that store the extra info in outboard data structures. We judge that the overhead is too great for commercial success. Customers buy benchmarks, and there are no security benchmarks.

'Tis true 'tis, 'tis pity. 'Tis pity 'tis, 'tis true.