Being safe on the internet (was Re: Here we go again - ISP DPI, but is it interception?)

[Charles Lindsey]

On Sat, 07 Aug 2010 17:15:05 +0100, Ian Mason  
<ukcrypto at sourcetagged.ian.co.uk> wrote:

> Talking of safe languages no one has mentioned my old personal favourite  
> Algol 68. it was even used as the systems programming language for a  
> capability architecture processor and OS by Maurice Wilkes, the late  
> Roger Needham, and others. Cue Dr. Gladman...

No, the safety in ALGOL 68 is too strong for systems programming work,  
where you have a definite requirement to "cheat" (i.e. to treat some bit  
pattern as being of different data types for different purposes - e.g. how  
else can one construct machine code and expect to be able to obey it?).

If you build in a few critical "cheating machanisms", then what you have  
is S3 (actually, that opened up more holes than it need have dome). And I  
expect that Roger Needham et al were using ALGOL 68C, which they were in a  
position to hack to provide such back doors as they found necessary.

My own ALGOL 68 compiler uses a specially hacked version of Pascal, for  
exactly the same reason.

-- 
Charles H. Lindsey ---------At Home, doing my own thing------------------------
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   Web: http://www.cs.man.ac.uk/~chl
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