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-1

With the advent of SE Linux, i would say that Linux now has all of the features of Multics. Not sure how that applies to any other versions.


4

Perhaps the best way of thinking about it is that Unix basically is a minimal implementation of Multics (the ideas in it a least) with absolutely everything that was not strictly necessary to bring up the system stripped out. So segmenting and virtual memory are not really needed (at least to get started). Complex permissions, ACLs or protection rings, ...


6

All these answers accurately describe the most salient features of Multics. One of the main consequences was that it could only run on specialized hardware. From a programmer's standpoint, dynamic links had a fantastic use: when debugging a program, you could pause on a breakpoint, fix your code, recompile it, update the link and continue execution (if you ...


7

Another significant difference between Multics and Unix was the size of the virtual memory accessible to a process. It is true that each Multics segment was limited to 255K 36-bit words in length. But each process mapped more than 300 such segments into its address space. About 1/2 of these segments belonged to kernel and inner-ring programming ...


8

A couple other significant differences between Multics and early Unix systems in the security area: Multics had rings (8 in commercial versions), whereas Unix only had two effective rings -- supervisor and user. This allowed privileged subsystems to be created that would run in process, but be protected from tampering by user (ring) manipulation. This was ...


10

In Multics, not only was all data mapped into memory, but all binary executables were what we now call DLLs. There was no natural "main program" concept: every binary executable was a compiled function. Processes were extremely "heavy": you got one when you logged in, and everything you ran was a DLL linked into that process. This messed ...


28

From this list of Multics features, almost all are recognizable in modern UNIX-style systems in one form or another. Looking for distinctions between is two is made difficult due to the longevity of UNIX and the proliferation of its children. For me, the most interesting distinction between Multics and UNIX (and most operating systems to follow) was Multics'...


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