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scott wrote:
> Because there are a tiny number of unix users who would follow
> instructions such as "you must run this attachment as admin to regain
> access to your bank account" from a random email.
http://en.wikipedia.org/wiki/Christmas_Tree_EXEC
Enough that it made international news at the time. Granted, this was IBM
big iron, not unix, but the principle is the same.
--
Darren New, San Diego CA, USA (PST)
Serving Suggestion:
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Warp wrote:
> Darren New <dne### [at] san rr com> wrote:
>>> If the very first version of DOS had had a similar account/password
>>> system as unixes,
>
>> ... then it wouldn't have run on an 8086, and MS would be broke.
>
> Or maybe we would have much better PCs today because they would not be
> based on (and mostly backwards-compatible with) a totally antiquated and
> obsolete architecture designed by IBM and Intel.
Maybe. But the machines had to be cheap enough for individuals to buy. More
importantly, they had to be cheap enough that they could go into the right
spot on the budget.
The only thing that made PCs "cheap" at the time was the clone makers. It's
hard to say whether things would have taken off or not, but it's not like
there weren't powerful UNIX-based machines with well-designed CPUs in the
mix at the time.
> Think about how the game industry has boosted the development of graphics
> cards. Imagine if the same boost would have been done to the PC architecture
> by OS vendors.
They had things like that. The Dolphin running Smalltalk. The Amiga's
specialized chips. LISP machines. IBM made an APL luggable computer I worked
on for a while. Heck, even the Mac was in the competition. And at the low
end you had dozens of radio shack, Apple ][, Vector Graphics, Tektroniks,
Kay-Pro, Commodore, and a dozen other brands of machines, many of which were
mostly compatible with each other at the software level via CP/M.
And the 8086/8088 was designed to run Pascal, which also didn't take off.
So... what happened?
>> It's hard to say. Most of the other systems of the day didn't have it either.
>
> Multi-user unix systems were certainly being used in many environments
> (eg. at universities with thousands of students) back when Windows95 didn't
> even exist. Back then things like logins, passwords and access rights were
> a given in those system. Yes, I have personal experience.
Sure. But the other computers you'd buy yourself, for one user, didn't have
any password stuff. I'm talking mostly the 8-bit computers that the IBM PC
wound up replacing. Sure, I used Solaris machines and even z8000-based UNIX
machines. They weren't something you'd buy for a secretary, tho.
And when you have a computer with thousands of users, you have someone
knowledgeable taking care of it, and everyone with access has a basic
understanding of computers or they wouldn't have access. It wasn't a general
purpose tool - it was a computing tool, and to use it, you needed a
fundamental understanding of how the computer worked.
>> Contrast with something like Singularity, where you explicitly list every
>> program you're going to run
>
> I never said that unix is the perfect system. I just said that it's
> *better* (in terms of safety) because the fundamental design is different
> (namely, it's intended to be a multi-user system).
Well, Windows is too, *now*. You can blame Windows users for the problems,
and blame Microsoft for Windows users. But having actually dealt with people
who don't know what they're doing, I have come to the conclusion that if you
put a general purpose tool in the hands of someone who has *no* idea how it
works, you're going to get scripted behaviors (i.e., people who take notes
on the steps they have to go thru to send a picture to their grandchild)
with no understanding or desire for understanding of the implications for
anything except "did it work?"
In other words, I don't think that having had logins from the beginning
would have taught people that mail can be forged. I mean, heck, do you think
having logins on the computer would teach people not to fall for Nigerian
scams? Do you think it would teach people not to fall for phishing scams?
Why would you think it would teach people not to fall for any other sort of
forged mail?
> The point is that if operating systems had had the proper design from
> the start, things like computer viruses wouldn't exist
I disagree. That's exactly why I listed all the security flaws that UNIX
fixed over time. Such OSes *would* have bugs, *did* have bugs, and they'd
continue to have bugs as new capabilities were introduced. Nobody has a
Morris worm before SMTP. Nobody had UUCP appending mail to /etc/passwd
before UUCP was around. Nobody stole passwords by connecting to a coworker's
X terminal before X was invented. Every operating systems has had viruses
and worms and such, including those who had multi-user access controls built
in to start with. Granted, it's hard to know exactly how many, especially
given the explosive growth in the number of machines in use and the
explosive growth in the number of computer-naive users. But, too, when a bug
was found in UNIX, it wasn't valuable to avoid reporting it, so they got
fixed instead of exploited, usually. Except Kevin Mitnick, who also made
international news by stealing stuff not from Windows machines, but from
UNIX machiens.
Now we're in a different world, where it's actually valuable to find and
exploit flaws, rather than reporting them when you come across them in
normal usage. (Sort of like now suddenly we need to protect airplanes from
terrorists, and not just the passengers. :-)
Basically, history does not bear out your statement, and the disproof is why
I listed all the UNIX flaws that had been fixed over time.
Heck, by all estimates, Mac OSX has more security holes in it than Windows
does (per installed unit, obviously), and it's based on an OS that has
always had logins.
That said, yes, certainly a system that has always had multi-user
authentication (and, more importantly, a separation of administrative duties
from daily operations) is superior to one that doesn't. But when every
system now has multi-user controls, and people try to deliver applications
over the internet yadda yadda, you wind up with viruses that don't need
administrative privs to propagate. I suspect that's the vast majority of
active viruses now - those that steal personal information or add you to a
bot-net, neither of which need (or even want) admin privileges.
--
Darren New, San Diego CA, USA (PST)
Serving Suggestion:
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Warp wrote:
> I wouldn't be surprised if that was the case today as well.
I saw an interesting article a couple weeks ago (on LWM?) where the author
looked at the security bugs fixed, and tracked back thru the archives to
figure out where they'd been introduced, to see if the number of security
holes in Linux is going up or down. Apparently, the number is down, very
slowly, but it's close to the measurement noise. (It's hard to tell where a
bug was introduced in a system where it's a number of interacting systems
that cause the bug, for example.)
--
Darren New, San Diego CA, USA (PST)
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Darren New <dne### [at] san rr com> wrote:
> I don't think it applies any longer, tho. Indeed, in many ways I think
> Windows might have a more secure architecture than UNIX nowadays, even if in
> practice it's not quite up to snuff and in practice it gets attacked more.
Has the amount of viruses, worms and especially malware declined with
Windows Vista and 7?
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- Warp
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Warp wrote:
> Darren New <dne### [at] san rr com> wrote:
>> I don't think it applies any longer, tho. Indeed, in many ways I think
>> Windows might have a more secure architecture than UNIX nowadays, even if in
>> practice it's not quite up to snuff and in practice it gets attacked more.
>
> Has the amount of viruses, worms and especially malware declined with
> Windows Vista and 7?
Compared to XP? I would certainly think so. More importantly, they've moved
to attacking things *other* than the OS. Like java in web pages, or trojans,
or phishing scams. I don't think that the number of malware attacks says
much about the security of the systems nowadays, as much as the popularity.
--
Darren New, San Diego CA, USA (PST)
Serving Suggestion:
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On 20/12/2010 06:41 PM, Warp wrote:
> On the subject of virus scanners in particular, I'd say that the very
> need to have such scanners is a symptom of fundamentally bad OS design.
I'd go along with that.
> The unix philosophy of OS design has always been a step or two closer
> to the safer design (with respect to computer viruses and other malware)
> then the typical DOS/Windows (and other similar OS's in the past) design.
> The reason for this is that unixes have always been designed to be
> multi-user operating systems while DOS/Windows has been designed to be
> a single-user OS with no regard to security.
That's pretty much it, right there.
> The DOS/Windows design always took basically the exact opposite approach:
> Whatever the user wants to run or do, the OS allows.
For a machine which is physically incapable of being networked, this is
a perfectly reasonable way to proceed. The Commodore 64 and the ZX
Spectrum had exactly the same "flaw" in their design. Only if a computer
is *capable* of being used by more than one person does any question of
"security" even exist.
> Unfortunately it took over 20
> years for Microsoft to rid itself of this mentality (for some reason MS
> has always been very slow to adopt certain ideas).
*This* is where it all went wrong.
Remind me: Is this or is this not the same Microsoft that famously took
the additude of "oh, this 'Internet' thingy is just a trendy fad; it'll
never last"? For a long, long time they seemed to believe that
networking was somehow "unimportant".
Either way, when they realised the true situation, they should have
changed their design practises. Radically.
> NT had security, but it wasn't even intended for normal users.
No, it wasn't. Which is a pitty, because it was quite a good OS.
Still, the main OS kernel lives on in some form. The Win9x kernel is
gone, and 2000, XP, Vista and 7 are all based (increasingly loosely) on
the NT kernel series.
In some ways, NT actually has *more* security features than Unix. For
example, take file security. Under Unix, I can set permissions for one
user, one group, and everybody else. Under NT, I can set permissions for
as many users and user groups as I damned well like. And this isn't a
theoretical ability; I use it extensively in my day job. Not only that,
but Unix has umask, while NT actually allows you to set the default file
permissions on a per-folder basis. And to reset the permissions on all
the files in a folder easily. Hell, I can even control who is allowed to
*see* the permissions on a file or folder.
On top of that, you make the OS log a record every single time a
particular action is performed on a given file. (Unix, on the other
hand, doesn't even provide a way for a process to be *notified* when a
file changes, much less to log such changes at the OS level.) Again, I
can control this at the file level, so I only get log entries for files
that I actually care about, not every single file in the entire
filesystem. And not for every action, and not for every user.
And that's just files. You can also set permissions controlling who is
allowed to kill a given process. Or clear the print jobs in a given
queue. And more besides. (Sadly, the OS GUI doesn't expose most of this
very useful control, and there are certainly no CLI tools for this
either. Indeed, if you want to set file permissions, you can *only* do
it via the GUI. Well, no, now there's PowerShell which can probably do
it...)
> It wasn't until XP that some
> *semblance* of security was introduced (yet, nevertheless, the mentality
> of the regular user being by default the superuser was still there
NT was where the big security changes happened. Before NT, any talk of
"security" was a nonesense. XP is just the first really well-known
consumer OS to feature these changes. (Windows 2000 didn't really get
noticed much, for whatever reason. Note that Windows 2000 /= Windows ME.)
Unfortunately, it turns out that 99% of all Windows software still
*assumes* that it has permission to do everything. And thus, you come up
with stupid glitches like, for example,
Nero claims that you do not possess a CD burner, *unless* you are
logged in as a superuser.
One could argue that it's not so much /Microsoft/ that is slow to adapt,
of even it's /users/. No, it's the people writing Windows software. If I
had a penny for every time I've had to do something stupid just to make
the buggy, barely-functional device driver for some crappy cheap-arse
piece of hardware work...
Of course, Microsoft don't really help themselves sometimes. They have
an almost obsessive tendency of making everything as scriptable,
programmable and customisable as possible. I guess because all those
extra features look good on the tin?
For example, if you use Outlook (not Outlook Express) you can create an
"email" which is actually a full-fledged application, in effect. (This
might also require Exchange, I'm not sure.) It ranges from simple stuff
like sending out appointments and questionnaires, right up to building
complex fillable forms, and having the server receive the responses and
do non-trivial processing with them, possibly producing additional
emails in response. Stuff like that.
All of which is very *powerful* and everything. But the net result is
that everything from emails to Word documents to spreadsheets,
databases, presentations, and so forth all can have arbitrary executable
code embedded in it, and more often then not executed immediately as
soon as you touch the time, often without you even realising it. This
enables you to create very "rich" documents. For example, the other day
I saw a PowerPoint presentation which is like a hyperlinked, browseable
product catelogue. Very impressive stuff. And it's no secret that you
can use Access to build what ammounts to a desktop application.
If you think in terms of shiney features, all of this sounds fanstastic.
If you think in terms of computer security, all of this sounds like a
catastrophy just waiting to happen. I mean, who thought that a *word
processed document* being able to alter the local filesystem was a good
idea?! Most users have no clue that you can do this. But I promise you,
you can. (Or, you could. These days as soon as you open a Word document,
you have to OK a dozen messages just to make it open, regardless of
whether it does anything even mildly dangerous.)
Of course, having access to the local filesystem allows a Word document
to be part of a big happy desktop application, developed using just MS
Office. Why write a GUI application when you can just customise Word a
little, and use a flat XML file as your database?
Now, if the system had been designed with security in mind from the
start, nobody would have done anything so stupid. But now all these
features exist (and, weirdly, continue to be designed), and somehow you
have to make it secure. MS's idea of "make it secure" isn't "disable
local filesystem access unless there's a damned good reason to enable
it". It isn't even "check whether the macro tries to access the local
filesystem" (which is trivially checkable). No, it's "slap a big, fat,
flashing warning on top of EVERYTHING, dangerous or not". Because, let's
face it, that's very easy to code.
And after the 198th time the user sees this annoying, unecessary error
message, they just stop paying attention. And then when a *real* threat
comes along, the user will blindly and automatically click "yes, please
run this unsigned code". Because they've had to click it a thousand
times before in order to get stuff done.
This is not "security". The whole XP Security Center is nothing more
than a nag screen that constantly whines at you. "Turn on updates.
Install a pricey AV product. Turn on the firewall." It does nothing to
actually increase security. (Automatic updates themselves may do. But
Linux has copied that idea too now...)
Really, there are several reasons why Windows (and related MS products)
are less secure than their Unix counterparts:
- Microsoft failed to realise that networks would become "important"
(and hence, security would be necessary).
- Once they did decide that networking actually was the future, they
implemented lots of security stuff but failed to really make full use of it.
- There is now a huge codebase of cheap, buggy, unsupported software
which people expect to work on Windows. If you start actually doing
things in a secure way, most of this software will break. (This is
technically a GOOD THING, but it doesn't sound very good to the people
who just want to do their stuff.)
- Microsoft thinks that endless rafts of whizzy features are more
important than computer security. (That's quite a serious problem, right
there.)
- Unix is the OS for computer experts. Windows is the OS for idiots so
stupid that arguably they shouldn't be let near a computer in the first
place. Wanna guess which one has the biggest security problems?
- Windows systems outnumber Unix systems 10^4 : 1. Wanna guess which one
most people spend their time trying to attack?
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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Orchid XP v8 wrote:
> Either way, when they realised the true situation, they should have
> changed their design practises. Radically.
Really, few other people understood the security flaws at the time either.
HTTP wasn't invented with encryption in mind. SMTP had no controls on who
could send mail. Basically, there wasn't even a standard encryption suite
until long after Windows was networked and HTTP started being used for
commercial applications.
> Indeed, if you want to set file permissions, you can *only* do
> it via the GUI.
cacls is so old it's deprecated in favor of icacls.
And no, Windows doesn't tend to provide command-line tools for things you
can do via scripting. That's what scripting calls are for, and why
powershell is looked on so favorably by windows admins.
When your fundamental OS interface is essentially object-oriented and
API-based, you don't get a whole lot of non-programming command-line tools
to manage stuff. It's only when most of your configuration is stored as
text files that you get text-based tools to manage it.
> Unfortunately, it turns out that 99% of all Windows software still
> *assumes* that it has permission to do everything.
I don't believe that's true any more. It might have been when XP first came out.
> One could argue that it's not so much /Microsoft/ that is slow to adapt,
> of even it's /users/. No, it's the people writing Windows software. If I
> had a penny for every time I've had to do something stupid just to make
> the buggy, barely-functional device driver for some crappy cheap-arse
> piece of hardware work...
Exactly.
> Of course, Microsoft don't really help themselves sometimes. They have
> an almost obsessive tendency of making everything as scriptable,
> programmable and customisable as possible. I guess because all those
> extra features look good on the tin?
It's in part because they have big customers who need that stuff. It's not
like UNIX isn't scriptable programmable and customizable.
> All of which is very *powerful* and everything. But the net result is
> that everything from emails to Word documents to spreadsheets,
> databases, presentations, and so forth all can have arbitrary executable
> code embedded in it,
And *that* is exactly why malware is still around in multi-user systems. And
it happens in browsers and everything too, so it's not restricted to
microsoft code.
> And it's no secret that you
> can use Access to build what ammounts to a desktop application.
Well, that's kind of what it's for.
> And after the 198th time the user sees this annoying, unecessary error
> message, they just stop paying attention. And then when a *real* threat
> comes along, the user will blindly and automatically click "yes, please
> run this unsigned code". Because they've had to click it a thousand
> times before in order to get stuff done.
That's a part of the problem. You can't ask users to be making that sort of
decision, either at the "access the file system" level or at the more
fine-grained level. The Android mechanism makes a lot of sense to users. But
in a system where you don't declare what code you're going to run or what
privileges you need (which applies to both UNIX and Windows and most other
systems), this doesn't work.
And that's why I thought the new types of hardware coming out (portables,
games, phones, and custom server hardware) might provide a chance to get
away from these legacy problems.
> - Microsoft failed to realise that networks would become "important"
> (and hence, security would be necessary).
I disagree this was unique to Microsoft.
> - There is now a huge codebase of cheap, buggy, unsupported software
> which people expect to work on Windows. If you start actually doing
> things in a secure way, most of this software will break. (This is
> technically a GOOD THING, but it doesn't sound very good to the people
> who just want to do their stuff.)
Exactly.
> - Microsoft thinks that endless rafts of whizzy features are more
> important than computer security. (That's quite a serious problem, right
> there.)
I believe starting around the time of XP SP2 they realized their lack of
security was actually hurting their business.
> - Unix is the OS for computer experts. Windows is the OS for idiots so
> stupid that arguably they shouldn't be let near a computer in the first
> place. Wanna guess which one has the biggest security problems?
>
> - Windows systems outnumber Unix systems 10^4 : 1. Wanna guess which one
> most people spend their time trying to attack?
Yes and yes.
--
Darren New, San Diego CA, USA (PST)
Serving Suggestion:
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On 20/12/2010 05:53 PM, Darren New wrote:
> that traditional OSes hold back the more sophisticated (as in, far from
> machine language) languages.
Perhaps. I guess it kind of depends on what you're trying to do. If you
have an application that just does its computations in its own little
world, then it's fine. If, on the other hand, the application wants to
do arbitrary stuff with the whole machine, then... yeah.
Wasn't there an OS written in Smalltalk at some point? (Or was that only
for special hardware?) Certainly you can see that if the Smalltalk
runtime was running on the bare metal, it would have all sorts of
interesting consequences. (For example, since *everything* can be
changed, you could invent some new bizare concept of files.)
Speaking of which...
http://halvm.com/
That's Haskell running on bare metal. (Well, OK, no it isn't, it's
running under a Xen hypervisor. But that's /almost/ the same thing.)
Apparently the guys at Galios actually use this thing, so that (say)
your web server runs in one VM, all by itself, and your DB runs in
another VM, and so on. But it would be interesting to see what happens
if you tried to write an actual "operating system" in Haskell, rather
than just an application.
> http://www.artima.com/lejava/articles/azul_pauseless_gc.html
That contains a lot of "look at us, aren't we clever!" and not very much
technical detail. It seems the only novel detail is that they're using
the memory protection hardware to trap and remap accesses to moved
objects. That's a neat detail, and one which (they assert) would be too
inefficient with a normal OS. But that seems to be just about it.
Haskell has a rather interesting invariant: since *most* objects are
immutable, old objects can never point to new objects. It seems like
this should make some kind of interesting GC algorithm possible.
Personally, I thought the article on GC avoiding paging was more
interesting.
> Traditional file system interfaces probably do too.
Now, do you mean "file systems", or do you mean "interfaces to file
systems"?
> It's interesting that this sort of stuff is starting to get to the point
> where people will be willing to break with compatibility at some level.
> Phones, game consoles, set-top boxes, and eventually probably
> "enterprise" or "cloud" type servers will all be willing to consider a
> different operating system that puts limits on compatibility with
> previous languages and libraries.
Well, we'll see what happens.
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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Orchid XP v8 wrote:
> Perhaps. I guess it kind of depends on what you're trying to do. If you
> have an application that just does its computations in its own little
> world, then it's fine. If, on the other hand, the application wants to
> do arbitrary stuff with the whole machine, then... yeah.
Not necessarily. There are memory models that really just don't mix, for
example. GCed memory with non-GCed external resources is the classic. This
paper describes how if you assume you have a C-like/Pascal-like workload,
using thousands of page faults a second to do GC isn't going to be
efficient. Etc.
> Wasn't there an OS written in Smalltalk at some point? (Or was that only
> for special hardware?)
Yes. The "dolphin" computer. It had programmable microcode, so when you
booted a Smalltalk image, the machine code *was* smalltalk bytecodes. When
you booted a COBOL program, the machine code was appropriate for COBOL.
> Certainly you can see that if the Smalltalk
> runtime was running on the bare metal, it would have all sorts of
> interesting consequences. (For example, since *everything* can be
> changed, you could invent some new bizare concept of files.)
They had what you'd consider a bizarre concept for files. That's the point.
You didn't have to worry about "destructors" for files, precisely because
"file" was built into the language, not the OS. So to speak.
> if you tried to write an actual "operating system" in Haskell, rather
> than just an application.
But that's the point. When your application runs on the bare metal, there's
no distinction between OS and application.
>> http://www.artima.com/lejava/articles/azul_pauseless_gc.html
>
> That contains a lot of "look at us, aren't we clever!" and not very much
> technical detail. It seems the only novel detail is that they're using
> the memory protection hardware to trap and remap accesses to moved
> objects. That's a neat detail, and one which (they assert) would be too
> inefficient with a normal OS. But that seems to be just about it.
That's the only neat technical trick they used to implement their other
tricks. I think it's more interesting that they're actually getting away
from the linear memory model that C and Pascal foisted on us.
In other words, they're using an OO memory model. Objects are contiguous
blobs, but it doesn't really matter beyond that where they are in the
address space. So instead of doing a compacting garbage collection in a
linear space, they do a compacting garbage collection on a per-page basis.
*That* is really the innovation.
> Haskell has a rather interesting invariant: since *most* objects are
> immutable, old objects can never point to new objects. It seems like
> this should make some kind of interesting GC algorithm possible.
Erlang takes great advantage of that too, yes.
> Personally, I thought the article on GC avoiding paging was more
> interesting.
Yeah. Again, it's the sort of thing you have a hard time doing in an OS
tuned for something with a memory model like C's.
>> Traditional file system interfaces probably do too.
>
> Now, do you mean "file systems", or do you mean "interfaces to file
> systems"?
Interfaces. The reality of file systems nowadays isn't anywhere near what
the interface looks like. Internally, it's much closer to multic's file
system, yet it's generally presented with UNIX file system semantics.
(In Multics, the basic way of getting to a file was essentially memmap.
That's why UNIX files are all represented as an array of bytes, with no
records, no insert/delete bytes, etc. It's modeling multics' interface
without the convenience of either having it in memory *or* having the OS
provide you useful services.)
> Well, we'll see what happens.
Yeah, sadly, I don't have a whole lot of hope. Altho the thing with each
application running in its own Xen hypervisor slot sounds interesting. I'll
have to look at the implications of that a little more closely.
--
Darren New, San Diego CA, USA (PST)
Serving Suggestion:
"Don't serve this any more. It's awful."
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On 22/12/2010 06:42 PM, Darren New wrote:
> Orchid XP v8 wrote:
>> Perhaps. I guess it kind of depends on what you're trying to do. If
>> you have an application that just does its computations in its own
>> little world, then it's fine. If, on the other hand, the application
>> wants to do arbitrary stuff with the whole machine, then... yeah.
>
> Not necessarily. There are memory models that really just don't mix, for
> example. GCed memory with non-GCed external resources is the classic.
And yet, code written in languages assuming GC management and languages
assuming manual management can not only interoperate, but even be linked
together in the same process image.
> This paper describes how if you assume you have a C-like/Pascal-like
> workload, using thousands of page faults a second to do GC isn't going
> to be efficient. Etc.
True enough.
>> Wasn't there an OS written in Smalltalk at some point? (Or was that
>> only for special hardware?)
>
> Yes. The "dolphin" computer. It had programmable microcode, so when you
> booted a Smalltalk image, the machine code *was* smalltalk bytecodes.
> When you booted a COBOL program, the machine code was appropriate for
> COBOL.
That sounds moderately mental. I'd hate to think what happens if you get
the microcode wrong...
>> Certainly you can see that if the Smalltalk runtime was running on the
>> bare metal, it would have all sorts of interesting consequences. (For
>> example, since *everything* can be changed, you could invent some new
>> bizare concept of files.)
>
> They had what you'd consider a bizarre concept for files. That's the
> point. You didn't have to worry about "destructors" for files, precisely
> because "file" was built into the language, not the OS. So to speak.
Not even built into the language - built into a library. And,
presumably, by changing that library, you can change how the filesystem
works...
(Does anybody remember how "Longhorn" was supposed to ship with a
filesystem that was actually a relational database? *Really* glad they
scrapped that idea!)
>> if you tried to write an actual "operating system" in Haskell, rather
>> than just an application.
>
> But that's the point. When your application runs on the bare metal,
> there's no distinction between OS and application.
Well, to some extent there /is/. By definition, an application is
something that solves a real-world problem, and an OS is something that
provides services to applications. Although in the case of something
like a Smalltalk or Haskell OS, the "OS" might be statically linked into
the application image - i.e., the "OS" might just be a runtime library.
> In other words, they're using an OO memory model. Objects are contiguous
> blobs, but it doesn't really matter beyond that where they are in the
> address space. So instead of doing a compacting garbage collection in a
> linear space, they do a compacting garbage collection on a per-page
> basis. *That* is really the innovation.
Sure. If the virtual address space supports it, why not? (Other than
"because most OS designs assume that you would never want to do such a
thing".)
>>> Traditional file system interfaces probably do too.
>>
>> Now, do you mean "file systems", or do you mean "interfaces to file
>> systems"?
>
> Interfaces. The reality of file systems nowadays isn't anywhere near
> what the interface looks like. Internally, it's much closer to multic's
> file system, yet it's generally presented with UNIX file system semantics.
>
> (In Multics, the basic way of getting to a file was essentially memmap.
> That's why UNIX files are all represented as an array of bytes, with no
> records, no insert/delete bytes, etc. It's modeling multics' interface
> without the convenience of either having it in memory *or* having the OS
> provide you useful services.)
OK, now I must know... WTF is this "memmap" that I keep hearing about?
>> Well, we'll see what happens.
>
> Yeah, sadly, I don't have a whole lot of hope. Altho the thing with each
> application running in its own Xen hypervisor slot sounds interesting.
> I'll have to look at the implications of that a little more closely.
Remember that Galios mainly does work for people who want high assurance
software. Stuff with mathematical guarantees of correctness, and so
forth. For that kind of insanity, being able to guarantee that the OS
isn't going to do something weird (because there isn't one) is probably
quite useful. I'm more dubious about how useful it is for everyone else.
The idea of experimental OS design using Haskell is quite interesting,
however.
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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