From the title linky: " Mobility is only available for Windows and Linux." Good job no-one bases their mobile appliances on Mac OS X ;-)
It’s getting there, now has the ability to display load commands (though it only reports useful information for LC_SEGMENT and LC_SEGMENT_64 commands):
Again the screenshot depicts the OmniDazzle binary for no reason other than it’s a nontrivial file. The directions in which to take the filesystem are now numerous: I can add info about the remaining load commands (v. useful), the raw data for each segment (somewhat useful), and the sections in each segment (v. useful). Whether the filesystem will eventually get to the level of symbol resolution, I’m not sure :-).
When looking through some of the configuration options on my laptop (well, it’s either that or go to the pub and socialise with humans) I came across something I couldn’t account — pardon the pun — for. A new user account on the system, short name messagebus, full name "Message Bus" user id 506. Now messagebus looks like the name of a system daemon user, but that full name looks like some clueless skiddie made a mistake creating the user account, especially as the uid is that of a regular user. That’s the kind of mistake no self-respecting installer would make.
So, what had this phantom user done? Well, thankfully, nothing. Neither the shell nor home directory was real, and wtmp/utmp showed no activity. Neither did the ssh logs – but in looking for them I realised that I don’t actually use ssh on the box, so turned it off.
Anyway, it turned out to be an innocuous issue – the MacPorts installer for dbus creates this bogus user, which I’ve since deleted. This Apple forums discussion explains more.
It needs some polishing and more functionality before I’d call it useful, then I have to find out whether I’m allowed to do anything with the source code ;-). But this is at least quite a cool hack; exploring a Mach-O file (thin or fat – in this case, I used the OmniDazzle executable which is a fat file) as if it’s a file system. FUSE of course makes it easy, so thanks to Amit Singh for the port!
One reason that microkernels win over everything else (piss off, Linus) is that stability is better, because less stuff is running in the dangerous and all-powerful kernel environment. MacFUSE, like FUSE implementations on other UNIX-like operating systems, takes the microkernel approach to filesystems, hooking requests for information out of the kernel and passing them to user-space processes to handle. Here’s the worst that can happen when screwing up a FUSE filesystem:
Now that might sound not only like a recipe for lower-quality code, but also like I’m extolling the capability to create lower-quality code. Well no it isn’t, and yes I am. The advantage is that now the develop-debug-fix cycle for filesystems is just as short as it is for other userland applications (and HURD translators and the like). This provides a lower barrier to entry (meaning that it’s more likely that interesting and innovative filesystems can be created), but also a faster turnaround on bugfixes (no panic, restart, try to salvage panic log… no two-machine debugging with kdb…) so ultimately higher-quality filesystems.
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p>The justification for the iPod Touch upgrade fee (to enable the new apps, which are actually deployed-but-disabled by a free firmware upgrade) is the same as the justification given for the MacBook wireless upgrade fee last year – that adding new features to a product that isn’t sold as a subscription service needs to be charged for. That in itself is odd – it means that the regulators in the States get to set a price (if not the price) for hitherto free products offered by companies. But it raises a more interesting question – what constitutes a new feature? If a bugfix renders a previously-unusable feature usable, is that charged for? If a security fix makes it possible to use a system in a different environment, should that be charged for?
About nine and a half years ago, a sixteen-year-old gadget boy in Weymouth made a simple mistake. Given the already near-complete shift of the music industry from the cassette tape to the Philips compact disc, and the superior portability and resilience of the Sony MiniDisc format, this boy decided that it was obvious the world was going to adopt this format. So our protagonist went out and bought a MZ-R35 walkman. Three years later, and although the writing was by now on the wall for the storage format, he added an MD-M3 to his collection.
I now believe I own all five pre-recorded MiniDisc albums ever made (though I don’t remember when I bought Hours by Bowie, and can only think that I bought Recurring Dream because at the time I fancied a girl who liked Crowded House), and have swathes of my vinyl and tape collection "backed up" to recordable MDs. But the rest of the world forgot to catch up with me! Where are the Hi-MD drives built in to laptops? Even Sony don’t offer that… Come to that, why do we still put up with crappy scratchable CDs? iPods may be a damn sight more convenient than my MD walkman is, but the bandwidth of an amazon package containing MiniDiscs is still far higher than the connection between my laptop and iTunes.
I still intend to find the required cable and port the rest of my LPs to the format though, as MDs are definitely more portable and resilient than is vinyl. And I haven’t actually listened to Bauhaus’ 1979-1983 in years.
So almost the entire world has exploded with news that Microsoft haven’t bought Yahoo!, but are at least waving ridiculous amounts of TEH CAHS under the noses of the shareholders. But what would be the outcome of such a takeover? Microsoft and Yahoo! are in pretty much the same position, they both have technologically acceptable “online presence” services which are marketed really badly such that a competitor virtually owns the market. The only example of a service between them I can think of which is vaguely market-leading is Flickr, although Yahoo! Groups (which was eGroups) might still be popular, I expect that Facebook and Google groups are at least comparable, if not larger than it. Hotmail and Yahoo! Mail are both familiar names, but then online mail is now a free and worthless commodity, and everyone has been playing catchup with Gmail for the last couple of years. People don’t “Windows Live Search” a thing, they “Google” it. People don’t “Yahoo! Video” their dogs on skateboards, they “Youtube” them.
So the post-acquisition world would go from two implementations to one, but one that’s still being marketed into the ground and with a few fewer workers. And all the transitional pain that Microsoft will impose on Yahoo! services, when someone remembers that FreeBSD isn’t a Microsoft solution. M$ seem to be of the opinion that with a market they don’t lead and $45Bn, the best approach is to lose the $45Bn and hire some other people who don’t lead the market. Not, like, take that $45Bn and make their stuff better.
As in any good mystery, the question is who done it? MacNN reports a flaw in Tiger, Leopard in which an authenticated copy operation gives the destination files (the copies) the ownership of the logged-in user, not of the name they used to authenticate. The question is, which user did the copy?
Let’s say there’s a system with Alice Administrator and Richard Regular-User. Richard downloads a new application from the intarwebs, and wants to put it in /Applications (though why? Why can’t he just put it in ~/Applications like a good little user? Never mind). The thing is, he doesn’t have the right to do that. Finder presents him with an authentication dialogue, and no matter how many times he enters his username and password correctly, he can’t acquire that right. However, he sees Alice walking past in the corridor and asks her to enter her admin credentials. For whatever reason, she agrees – now Alice has authenticated and Alice has acquired the right to copy the files. So even though Richard requested the copy, it was actually Alice who performed it. Therefore Alice created the files at the destination, so they should be owned by Alice.
The only thing which muddies the waters (and leads to the conflict of convenience vs. security which is described in that article) is that in many, or indeed most, cases on OS X where this will arise, Alice and Richard are actually the same person – Sammy the Single (Security-conscious, hence separating their use of the system into regular and admin accounts) User. It’s a convenience that as Richard wanted the files copied, Richard now owns the copy – but this defeats the point of Richard existing, which is that Sammy doesn’t want to be able to change /Applications without being warned.
Interestingly the same question doesn’t get asked of the sudo command – it’s clear that if I type sudo ditto Foobar.app /Applications/Foobar.app it’s the super-user who does the work.
A frequently-heard rider on the statement that Mac OS X "is more secure than Windows" is that fewer people are prodding its weak spots, because it has fewer users. Well, Windows Vista has a market share comparative to Mac OS X (all versions), and this report describes the security statistics as being somewhat comparable, too. So there we go.
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