Wikipedia:Reference desk/Archives/Computing/2009 June 6

= June 6 =

Portable VirtualBox for Linux?
I am trying to make a portable version of VirtualBox to run on Linux, but I'm not sure what might be the best method to use... I already have a container format for it, RUNZ (think of it as a self-extracting file, but even better), but now the problem is getting a "portable linux kernel" so that VirtualBox can run on any PC without the need to install the kernel drivers... What method do you think is best: user mode linux, OpenVZ, chroot (I don't think that works for this!), FreeVPS, Linux-VServer... ? Any ideas...? Thanks. Hacktolive (talk) 03:17, 6 June 2009 (UTC)
 * Not sure if this will help you, but there is a Protable Virtualbox for Windows available here, might be able to get some ideas from how they do it 8I.24.07.715 (talk) 20:08, 7 June 2009 (UTC)

Sorting MSN contact list by e-mail address
I just downloaded the latest version of Windows Live Messenger. In previous versions, my contacts were organized solely by e-mail address. Now, when I go to Tools, Options, Layout, the only two options I see are organizing contacts by Display name or by First and last name. Is there anyway to revert to the way of organizing contacts solely by e-mail address? —Preceding unsigned comment added by Sjmcfarland (talk • contribs) 08:59, 6 June 2009 (UTC)

auto web crawler
I'm looking for a way to automatically download all pages from a given website, at set intervals of say three hours. The sites content changes every few hours, and the crawler must not overwrite the previous saved pages when it begins it's next download, but should update any pages which still exist since it's last crawl. It this possible? Sort of like creating a cache of any pages which existed so that I can search them later even if they have been removed from the actual website. —Preceding unsigned comment added by 82.44.54.169 (talk) 10:09, 6 June 2009 (UTC)


 * See wget. Another solution is httrack.  Tempshill (talk) 17:13, 6 June 2009 (UTC)
 * The main point was this was to be done automatically. This two programs have to be manually invoked —Preceding unsigned comment added by 82.44.54.169 (talk) 18:44, 6 June 2009 (UTC)


 * cron on *nix, Task Scheduler on Windows for scheduling. Hopper Mine (talk) 19:17, 6 June 2009 (UTC)

Reconstructing link from the href
On a badly designed web page, the link I want to use is hidden by something else so I cannot see it or click it. I have found the href in the source code. But the href only gives part of the URL. What else do I need to look for to reconstruct the complete URL please? 92.24.112.16 (talk) 11:47, 6 June 2009 (UTC)


 * Prepend the URL of the badly designed page, and a slash, to the href. Hopper Mine (talk) 11:52, 6 June 2009 (UTC)

I have tried that, and it does not work. I have also tried some variations such as removing the .htm part without sucess. Would the root be on the html page source code somewhere? 92.24.112.16 (talk) 12:15, 6 June 2009 (UTC)


 * Relative links are usually referred to the current web page, but this may be changed by the  tag . --Andreas Rejbrand (talk) 12:59, 6 June 2009 (UTC)


 * If you have the page up you may be able to tab to the link using the tab key and then press enter even if you are finding it difficult to click on it directly. Dmcq (talk) 13:31, 6 June 2009 (UTC)


 * If the link is there, but is overlapped by something else (which I guess is what you mean by "hidden") then you might be able to fix this by disabling styles on the page temporarily. In Firefox: view->page_style->no_style, in Opera: view->style->accessibility_layout  87.112.85.8 (talk) 14:10, 6 June 2009 (UTC)

Linux like security in Windows?
We all may be tired of Viruses in our daily lives. They are destructive and malicious, and damage our Computer to an enormous extent. Recently, Linux users have declared that Linux is more secure that windows. To understand this, we must understand why Linux is not quickly infected. There are three principle reasons for this, and these are:
 * 1) By default, autorun option is disabled in Linux.
 * 2) Linux can not easily play .exe, .bat and other executable files.
 * 3) The setup of Linux. This is perhaps the most interesting point. Linux has one root or superuser account, like the Administrator account in Windows. But generally, the user accounts we use on Linux are like the limited accounts on Windows. Tey do not have full access to the system,and the system files of Linux are kept away from their reach. For instance, when a Linux Computer Acount is infected, the Virus tries to infect the system files. But for this, the Computer asks the virus the root password. The virus fails to access the password, which is kept stored int eh System files. Hence the virus fails to access the system. The computer remains safe. ut here is a way to prepare the same setup in Windows.

Many have migrated to Linux from Windows for sake of security, but are not regretting for such a move, mainly facing the out-of-the-box usability of Linux. So, the challenge continues, causing each user to choose any one alternative, either the Grand environment and tremendous usability of Windows, or the Secure but complicated Linux (I have both in my possesion). Now, we have two alternatives, namely: Many of my friends use Windows for all purposes, and Linux for Internet Surfing, since Internet is the primary source of Virus and Malwares. Doing this is fair, but one problem is there, that is the speed of the PC decreases. So, we must focus onto the second option, that is to prepare a Linux like security setup in Windows. To do this, we should keep one Administrator account in Windows, and should outselves use a limited or poweruser account. Now, we cannot directly remove the Administrator account we use (not the default Windows Administrator) from the Control Panel/User Acounts. To do this, right click "My Computer Icon" and select "manage" or "manage local users and groups", whichever is available. Now, select Computer Management (local)/System Tools/Local Users and Groups/Users, and right click your administrator account (not the Default Windows Administrator titled "Administrator" itself), and select delete. But be sure, that you know the default Windows Administrator password. Now exit the Window, and go to All Programs->Run, and open it. A small run window will appear. There, in the box, type "control userpasswords2" and press enter. A window titled "User Acounts" will appear. There, select your limited account and click on Properties. Anew window will appear. There, select the Group Membership Tab, and select the "Standard User" radio button. Your account will now be a power user account. Lg off once and log in again to activate the Power User Account.
 * 1) "Using a multi-OS computer, having both Linux and Windows."
 * 2) "Preparing the Linux-like security setup in Windows."

Now, you may use this account to browse the Internet, and feel free, for most virus can not infect your PC now (even you do not use any Antivirus Software). But An antivirus is always good, so please try one. There are many available freely across the net. When ever you run any virus files unknowingly, the virus tries to access thwe system files, but fails, since it does not get any access to the Administrator password and can't open it. Now, only one question lies ahead. That is, if we download a trusted programme from the Internet, and want to install it, we won't be able to directly, because the Computer does not allow any power user to modify any system file. For this, we should press shift and right click the Installer and select "Run As" command. There, select the radio button "The folowing User" and type the user name "Administrator" exactly and enter the Administrator password. Then type the user name "Administrator" exactly and enter the Administrator password. Then it will get installed. Thus we have both the security of Linux and the power of Windows. By this way, can we make Windows XP to some extent more secure? Anirban16chatterjee (talk) 12:10, 6 June 2009 (UTC)


 * If all that means "is it better in XP to run most of the time as a normal user, and only run as administrator to do admin tasks" then the answer is "yes". Hopper Mine (talk) 12:14, 6 June 2009 (UTC)


 * Thanks for the answer. But my question is that,since normal or power users do not have rights or permissions to modify the system files, so if they, by mistake execute any virus, and the virus is primarily targetted to System files, will the virus be able to modify the System files? Anirban16chatterjee (talk) 12:27, 6 June 2009 (UTC)


 * Ideally, no. But viruses and other malware often come with a repertoire of exploits for privilege escalation, so while operating by the principle of least privilege is a good idea, it's by no means a complete solution. Hopper Mine (talk) 12:47, 6 June 2009 (UTC)


 * I took the liberty of breaking your comment into paragraphs to make it easier to read. Let me know if I've done this wrong.
 * The advice you provide is good basic advice, but many XP users find the restricted accounts too restricted for even day-to-day use. Vista is a big improvement is this area with the introduction of the much hated User Access Control. However, I believe the biggest factor in the vunerability of Windows to malware is the sheer amount of it compared to Linux.  Writers of malware. target their efforts at the largest market share and that is Windows.  Astronaut (talk) 13:02, 6 June 2009 (UTC)


 * The UAC article is User Account Control. I too thought the 'A' stood for access, or perhaps "argh". 87.112.85.8 (talk) 14:12, 6 June 2009 (UTC)


 * Thanks a lot to all of you, for answering mu question. And friend Astronaut, Thanks for splitting my paragraphs, you really added to the view of the writting. Actually, I am not very good in editing in Wkipedia, so I just did it wrongly. As for the fact about the day-to-day inconveinience faced by XP Users, can we use Run As shortcuts (with Administrator privileges) to overcome this trouble to some extent? 117.201.99.153 (talk) 12:35, 7 June 2009 (UTC)

GPL DRM Kits
This a really ironic question, but is there any DRM software licensed under the GPL? --Melab±1 &#9742; 20:22, 6 June 2009 (UTC)


 * Xpdf honours the DRM permissions in PDF files (limits on copy, print, extract-graphics). Xpdf is licenced under the GPLv2, and naturally the source code is distributed. The author is acutely aware of the irony, but feels obligated to do so.  This is because Adobe claims (and may well be correct) that anyone implementing a PDF reader infringes on its patents, and further Adobe agrees to licence such readers providing they honour the DRM features of PDF files they encounter. 87.112.85.8 (talk) 20:43, 6 June 2009 (UTC)


 * That's interesting, I was aware that Adobe had an agreed to allow people to implement PDF without paying royalties but didn't know they have such a caveat. Does Microsoft's XPS have similar problems? Nil Einne (talk) 09:29, 7 June 2009 (UTC)


 * Obviously it's a silly restriction though - if you have the source code then you can trivially circumvent the DRM. However, doing that is illegal in the US under the DMCA and in many other countries under similar laws.  SteveBaker (talk) 02:00, 8 June 2009 (UTC)