Wikipedia:Reference desk/Archives/Computing/2009 August 23

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August 23

chroot and graphical apps: is it possible?

is it possible to set-up a chroot and use graphical apps? I don't want them in a xnest window or similar, I want them to be displayed on my normal desktop, like all other apps. Is this possible? How can I do it? (I already have the chroot prepared) - SF007 - 05:07, 23 August 2009 (UTC)

Yes; but I think you might be confused about what chroot does. Which graphical application do you plan to use? I think anything which uses any dynamically linked libraries is going to complain if you chroot it and deny access to your library paths... are you writing the graphical applications yourself and statically linking them? Nimur (talk) 06:57, 23 August 2009 (UTC)

You could always copy the libraries your app needs into the chroot. The debian debootstrap package might be useful. --194.197.235.54 (talk) 11:13, 23 August 2009 (UTC)

Mediawiki Error - Still

Not writing this againRgoodermote  06:20, 23 August 2009 (UTC)

Chances are, everyone who looked at your question earlier was unable to answer it. Reposting probably won't help. If you can rephrase or elaborate on what the problem is, we might be able to help; but just reposting (especially when the original post is still on the desk) is not going to get you any more answers. Nimur (talk) 06:54, 23 August 2009 (UTC)

Well that is as elaborate as I can actually make it, I can tell you that it seems to have something to do with my version of PHP. As I never noticed it before till today that the PHP number was 5.1.37 not 5.1.33 and some Google searching turned up a lot of people complaining..but of course getting no answers..about this problem. When I updated my version of PHP is beyond me. I also got this little doozy recently "Warning: Parameter 1 to ConfirmEditHooks::confirmEditMerged() expected to be a reference, value given in ***\w\includes\Hooks.php on line 132". Second, I find it unlikely that there is not one single person on Wikipedia who can't answer this question. Rgoodermote  07:20, 23 August 2009 (UTC)

The obvious thing to try is to go to an earlier version of PHP, hopefully without the bug. StuRat (talk) 08:23, 23 August 2009 (UTC)

The Reference Desk is only read by a tiny fraction of Wikipedia users. I promise we're not holding out on you; nobody here seems to know the answer. Perhaps you should contact the developers of the software? --Sean 14:08, 23 August 2009 (UTC)

It sounds like a legitimate software bug (with MediaWiki); try contacting the developers. The message means that a wrong variable type is being passed to a function, which is the sort of thing they are probably interested in knowing about. --98.217.14.211 (talk) 16:45, 23 August 2009 (UTC)

(undent) Thank you to the above, as for downgrading PHP, I tried that, however it's nigh impossible, it for some reason will render Apache unstartable and the error does appear to be related to PHP, however it is most likely related to a variable that was probably removed from the latest PHP release that the software relied on..so yeah a bug. I looked around and it would appear that I am not the only one who is having this issue. Rgoodermote  22:59, 23 August 2009 (UTC)

I filed a bugzilla report. So I'd say this is resolved if anyone else wants to comment. Rgoodermote  23:13, 23 August 2009 (UTC)

To me, this does not look remotely like a bug with PHP. This looks like your extension is not for the version of MediaWiki that you are running. Each extension will state which version of MediaWiki it was designed for (and some work with multiple versions). -- kainaw™ 23:15, 23 August 2009 (UTC)

It ran fine before updating PHP, I used 1.16WMF for some time before and used only the software bundled with it. This only happened when setting up a wiki on the latest version of Xampp/Lampp (those two continually get misspelled by me by the way) which had the latest version of Apache, PHP and MYSQL. On earlier version of the Xampp/Lampp software the mediawiki software worked like a charm. Rgoodermote  00:11, 24 August 2009 (UTC)

I want to clarify that when I said it looked like a bug, it is with the software (e.g. the extension or MediaWiki or whatever), not PHP. --98.217.14.211 (talk) 02:19, 24 August 2009 (UTC)

To those who guessed software bug with Mediawiki, you would be correct. Rgoodermote  03:20, 24 August 2009 (UTC)

"This was fixed yesterday." Love it. Tempshill (talk) 05:30, 24 August 2009 (UTC)

Resolved

Practical measures to preserve privacy and security when computer is stolen

What can I do to preserve my privacy on the assumption that my computer will be stolen one day? I dont just mean keeping credit card details safe, but keeping correspondence encoded or otherwise private? Log-in and other passwords too. (A version of OpenOffice that works with encoded word-processing files would be a good idea.) Something good enough for the average computer -burglar or -fence not to bother with decoding it rather than just deleting it. This is a seperate issue from backing up files. 78.149.186.253 (talk) 13:14, 23 August 2009 (UTC)

The easiest way would be to just encrypt the whole hard-drive or at least the user directory. Most operating systems have ways to do this built into them (e.g. FileVault for Macs). If you want to encrypt the whole thing, TrueCrypt can do this. Doing it on a file-by-file basis is not terribly practical—that's a lot of passwords to type in, and makes it quite difficult to send you files to others, and there are cryptologic problems with encrypting lots of small files. --98.217.14.211 (talk) 13:42, 23 August 2009 (UTC)

I partially agree with 98. Although I've never done this, TrueCrypt can encrypt the entire hard disk, so it will be unusable to anyone who does not know (and can't guess) the password. BitLocker is Microsoft's full-disk encryption system, which comes with some versions of Windows Vista and Windows 7. Alternatively, you could use TrueCrypt to create a single "container" file on your hard disk that is encrypted, and store all your sensitive data in that container file. But it sounds like you want a little more certainty than that in the case of Outlook's .pst files being stored somewhere else, maybe temporary files on the hard disk will have sensitive data — whole-disk encryption avoids all those problems. Tempshill (talk) 17:26, 23 August 2009 (UTC)

I've used TrueCrypt for years and would reccomend it highly. As long as your computer is decent, you will not notice any performance decrease. — neuro^(talk) 15:45, 26 August 2009 (UTC)

Windows Movie Maker

Is it possible to download windows moviemaker to XP without downloading service packs? —Preceding unsigned comment added by 81.197.87.181 (talk) 13:54, 23 August 2009 (UTC)

Windows Live Movie Maker requires at least Windows XP with Service Pack 2 to run, so it's either install the service pack or don't install Movie Maker. (Is there any particular reason you don't want to install a service pack? I can't think of any.) Xenon54 (talk) 17:58, 23 August 2009 (UTC)

Well I can't imagine installing SP2 on a fresh Windows XP over dialup is a fun experience, particularly if you pay by the minute. For that matter installing over a GPRS connection. However the IP looks up to a Finnish ADSL connection which doesn't exactly speak 'slow connection' Nil Einne (talk) 18:09, 23 August 2009 (UTC)

A LOT of things require at least SP2 nowadays; in a developed country like Finland there is very little reason to use vanilla XP (not to mention the security vulnerabilities). --antilived^{T | C | G} 09:50, 24 August 2009 (UTC)

Java: loading only the objects you need

Hello! I'm working on a Java program that randomly creates simple sentences one-at-a-time from a bank of Word objects. Each word object will contain significant fields such as a string representation of the word, gender, part of speech, etc. The only way I know how to do something like this is declaring and constructing every Word into memory:

Word word1 = new Word("dog", Gender.MALE_AND_FEMALE, PartOfSpeech.NOUN);
Word word2 = new Word("man", Gender.MALE, PartOfSpeech.NOUN);
Word word3 = new Word("she", Gender.FEMALE, PartOfSpeech.PRONOUN);
//...

But each randomly generated sentence will only contain a few Words, and declaring all the Words the program can draw from uses memory way too inefficiently. I need a way to have the program load only the words needed for a sentence then dispose them and get new ones for another sentence. So, my question is, what is the most efficient way of accomplishing this? I was thinking about creating a file full of all the Words (or separate files full of related words, like noun file and verb file), and the program just randomly streams in all the objects it needs for each sentence, but I'm not sure how to do this or if this is the best way. Thank you for any advice!--el Aprel (^facta-_facienda) 21:28, 23 August 2009 (UTC)

If each instance of Word only contains a String and a couple of enums, that's really not using very much memory, so even tens of thousands of them won't take up that much storage. It sounds like you should have an array of Word objects (whether initialised from a file or from a static initialiser is up to you). But if you really are very hard-up for memory, and are sure that you only want a few Word objects in memory at once, then you'd need to load them from some randomly-accessible store (accessed by something like java.io.RandomAccessFile.seek) - but doing that will take some kind of index or a standard layout (which means it's a bit of work organising things). -- Finlay McWalter • Talk 21:39, 23 August 2009 (UTC)

What you have is a database, in the generic sense. There are many ways to store data in files for efficient retrieval. For your purposes a sorted CSV file may be suitable:

"dog","MALE_AND_FEMALE","NOUN"
"she","FEMALE","PRONOUN"

etc. More sophisticated requirements might make using a relational database sensible. For anything beyond a toy program or school assignment keeping the data in the program -- and recompiling when it changes -- is going to be a pain. --Sean 21:47, 23 August 2009 (UTC)

Help getting rid of horrible trojan

Hello. I few weeks ago I posted here about a virus horribly infecting my computer—"System Security 4.52". I got good advice to download Malwarebytes, which I did. It was successful in removing part of the virus but not all of it. Specifically, I was able to download it in safe mode with networking, and then ran it, and once downloaded, ran it in safe mode, where it found some of the files, which I deleted. Then I restarted and ran it again (now that I was able to open up the program, which the virus theretofore blocked) and it found more of the virus which I deleted. And everything looked fine—for a time, until the virus came back! I went through the same procedure again, and it came back again, and I've just done it for a third time in order to get online to write this post. Obviously, the virus is leaving something on my computer that is downloading itself back to my computer. I am running Avira Antivirus. Windows XP. Dell Dimension 8400. Thanks in advance.--141.155.22.185 (talk) 23:21, 23 August 2009 (UTC)

If I was you I would backup all my important data, reinstall OS, install antivirus, and scan the backupped data for viruses before starting to use it again, or better yet just dump it and be safe for sure. --194.197.235.54 (talk) 23:53, 23 August 2009 (UTC)

I don't know how to do that. If I could I would do a system restore but when I try it just doesn't work.--70.19.34.166 (talk) 00:21, 24 August 2009 (UTC)

Reinstalling windows should be an easy solution - did the computer come with an XP disc (CD)?83.100.250.79 (talk) 00:37, 24 August 2009 (UTC)

I agree with 194, I'd back up everything, format, reinstall, and start from scratch. You'll need your Windows disc. Tempshill (talk) 02:59, 24 August 2009 (UTC)

I heartily recommend AVG Free, Superantispyware Free and ComboFix.[1] ---— Gadget850 (Ed) ^talk 03:15, 24 August 2009 (UTC)

I would not reccomend using AVG (high false positive rate, low true detection rate) or ComboFix, the latter because it can screw things up if you don't know what you're doing. I've seen many a time where people have used ComboFix and it has caused major issues, hell, I've used it for a long time and it still occasionally goes mental. NOD32 (or Avira, if you're low on cash) is a good AV, but having worked with malware removal for years, I would certainly not recommend AVG. — neuro^(talk) 15:48, 26 August 2009 (UTC)