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Comment Re:Yes, deleted files are (sometimes) recoverable (Score 1) 56

For spinning rust that works just fine, most of the time. Flash is another story entirely. It's likely that your overwrites will get put into _other_ free cells, and the flash controller will mark the cells you're trying to overwrite as free, rather than overwriting them. Depending on your usage patterns, they might _never_ get overwritten. Aaaaaaand we're back to the problem we were trying to solve... just one layer lower. :(

There actually is a way, but it involves creating a file that's as big as the remaining space on the volume, to ensure that there are no flash pages that don't get rewritten. And even then, that doesn't quite guarantee that it will get overwritten because the flash page you're trying to overwrite could get spared and replaced with a free page. Obviously if you do that enough times, it will eventually get overwritten, but you'll also drastically shorten the life of the flash disk.

A better solution, of course, is to have a flash controller that supports TRIM properly and guarantees that overwritten pages get zeroed in a timely manner. If you have that, then overwriting the data once is sufficient, because the data will eventually get zeroed. And frankly, there's no good reason for a flash controller to not aggressively erase pages that are no longer tied to the filesystem (the old version of the data), because they are unlikely to ever be used again.

Comment Re:Not a SQLite problem (Score 1) 56

In SQLite, you can do "PRAGMA secure_delete=ON;" and it will subsequently overwrite all deleted information with zeros. This is turned off by default because it does more disk I/O. Alternatively, one can run "VACUUM" at any time to ensure that all deleted content has been purged from the database file.

The concern goes deeper than just disk I/O. On flash, there's a limited number of writes per flash erasure block, and using it in a mode that continuously overwrites everything you delete significantly increases the rate at which you burn through those write cycles. The OS is likely to coalesce a lot of those writes if they happen close enough together, but you're still abusing the hardware pretty badly by doing that.

The right approach is to come up with a reasonable policy for retention, e.g. "Guaranteed to not retain data more than n hours" and then vacuum the database every n hours, or when the OS tells you that your app is about to get terminated (assuming you can safely do it in such a short time), or when your app gets backgrounded (if you can't). Either way, vacuuming constantly is bad for the hardware, and never vacuuming is bad for security. The key is to find the right balance, and that pretty much requires your programmers to know that this issue exists, which most SQLite users no doubt do not.

And a couple of aspects of the design of iOS contribute to this problem negatively. If this were on a real computer:

  • You'd probably have a MySQL or PostgreSQL instance holding that data, and it would scrub periodically in the background. You can't do that you iOS, because you can't have a background daemon running when your app isn't running, so everybody ends up using SQLite, which is just barely enough of a database to be usable.
  • You wouldn't have the OS killing your app randomly while it is backgrounded, making it impractical to guarantee that you'll get n seconds to scrub every so many hours.

I'd love to see iOS add a centralized SQL database running on it at all times, with periodic scrubbing, with the ability to selectively share tables across apps, etc.

Comment Why the cloud anyhow? (Score 2) 20

Does the predictive capability really need a cloud connection? I stopped using SwiftKey as soon as I learnt it needed the Internet to function and thus the risk of sensitive data, such as credit card numbers, leaking. Beyond the privacy concern, the fact I can't use while without a data connection did not reassure.

Comment For example (Score 1) 12

Blocklist: Trump, Hilary, Clinton, DNC, RNC, Democrat, Republican, Libertarian, Green, gun control, s**t, f**k, h**l, ...

Actual posts filtered:

  • Google Trumps Apple as #1 on NASDAQ
  • California Drought Finally Over? Green Grass Says "Maybe"
  • Shitake Mushrooms Pulled Over E. Coli Concerns
  • Hello. My Name is...

Word bans don't work. They never did. To do this right would involve significant amounts of machine learning, and you wouldn't need a list of things to ban if they were doing that.

Comment Re:Dont care (Score 1) 374

I got the translucent drag bars to work pretty easily, but window outlines are still just one pixel,

That's a deal breaker for everyone who has turned on focus-follows mouse and turned off click-to-raise. I.e. good old X11 behavior that lets you copy/paste between overlapping windows while maintaining Z-order.

But these days almost all users run everything full screen, and have to context switch. Sigh. Dumbing down all over.

Comment RSS is broken (Score 1) 101

Can't just replace with, the RSS feed facility is badly broken.

RSS feeds seems to work at the top-level categories, but you can't turn your search results into an RSS feed anymore... Still got the RSS icon at the top of the page and in the META so your browser bar shows it. But both just show the same old HTML page instead of an RSS page:


Comment Re:Nothing of value was lost (Score 2) 39

Replacing Usenet with 8 million different web forums that I have to register with individually and use a different interface to read is not an improvement.

You don't have to visit any web forums to read them. Nearly every site has an RSS feed, and those which don't can be scraped and converted into RSS with something like

I would HATE using my smart phone to read the news if it wasn't for RSS. /.'s mobile site is the single worst piece of crap I've ever seen. But with RSS I'm fortunately able to read any and every site out there, in a uniform "eBook"-like format.

You can read my RSS tips here:

Comment Re:The safe 1 minute summary (Score 1) 120

I guess secondarily the punishment for bad actors may not fit the crime, but again we have a justice system for that.

I thought the justice system had abandoned pillory?

Anyhow, I think it will be hard to win any cases. Courts have sided with advertisers before, ruling that misleading ads are expressions of free speech - as long as they're not outright lying, anything seems to go. Caveat emptor, at least here in the US.

Comment Re:dark patterns huh? (Score 4, Interesting) 120

Notice how news sites like CNN are gradually going all video? And not the good videos that explain a lot succinctly or put you into a snippet of the news action, but those excruciating new wastes of bandwidth that just display story text, in a giant font, screen after screen, backed by nothing but a musical bed, until you realize that you have spent ten minutes watching one paragraph of text.

Yeah, it's like a powerpoint presentation set to music.
I don't think it's possible to get the information to bandwidth ratio any lower than that, but I guess I shouldn't underestimate marketing and management. I'm sure they'll think of something.

Comment Re:dark patterns huh? (Score 4, Insightful) 120

That was my thought too - a video?
AV is notoriously imprecise, and tricks people into judging by how they feel about the presentation instead of the actual contents.

And, of course, as the old sysadmin adage goes, a picture takes up more bandwidth than a thousand words. And video is orders of magnitude worse.

I also thought the new owners here listened to the discussion right after they took over, where they asked whether /.ers wanted video links or not. Overwhelmingly, we did not.

Comment Re:A funny story (Score 2) 164

Bernie got roughly 43 percent [] of the popular vote.

That's only the primary count. If you include the caucus votes, he got about 49% of the popular vote.

Now, we know the DNC was in the bag for Hillary and pushing the media to cover her favorable. It's generally considered that good press is worth about 5% in the polls.

The Superdelegates were for Hillary, but we probably would have had a situation where Bernie got the popular majority but Hillary got the nomination, if the DNC had played neutral.

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