Wikipedia:Reference desk/Archives/Computing/2011 June 23

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June 23

Running program for Unix-based OS

Can I run softwares for Unix-based operating system on Windows?125.235.100.105 (talk) 01:07, 23 June 2011 (UTC)

That's a complicated question.

The short version is that most unix-only software will not run natively on Windows, however if the software you're looking to use is open-source, it's very likely that someone has made a windows version of it.

And, in a worst case scenario, you could probably install linux within a "virtual machine" on your windows machine, though that would probably be more trouble than it was worth.

If you can tell us what software you're specifically interested in we may be able to help. APL (talk) 03:35, 23 June 2011 (UTC)

It's not that difficult to install a linux distribution as a virtual machine in Windows. I think it's possible with the Microsoft Virtual PC and I know it's possible with Oracle VirtualBox. I have 3 Ubuntu virtual machines running on VirtualBox.--Phil Holmes (talk) 08:08, 23 June 2011 (UTC)

The software I looking for use is a platform that run Unix-based softwares on Windows, like Wine that run Windows software on Unix-based operating systems. 125.235.100.158 (talk) 09:23, 23 June 2011 (UTC)

That's co-linux. You can download a compressed image of a 1GB file system running Ubuntu for it. Extending the image is a bit of a pain - you are probably better off creating a second image for storing your documents (/home). You should also install an X-server if you want to run graphical programs. cygwin's or mingw's ones is probably the easiest. Ask here again if you need advice to set it up. CS Miller (talk) 12:07, 23 June 2011 (UTC)

There's always Cygwin. It provides a Unix-basd compatibility layer on top of Windows. You can start Cygwin as a normal Windows program, and it presents you with a Unix shell. It's not an emulator - that shell is running directly on Windows. You can traverse your own Windows file system through the Unix shell interface, to read and write files. You cannot run Unix binaries from "real" Unix distributions like Linux, Mac OSX or Solaris, but you can get Unix-based source code and compile it in Cygwin, which will then result in completely native Windows binaries that can be run from inside Cygwin. JIP | Talk 19:15, 23 June 2011 (UTC)

Ubuntu: Command + ` OSX equivalent?

On the Mac, I use Command + ` (the tilda) to cycle through windows in the current application (eg terminal or chrome). It's like alt + tab except only for the current application's windows. I also don't want any flashy graphics like exposee or anything. Is there anyway to do this on Ubuntu (possibly on compiz?)? Thanks! — Preceding unsigned comment added by Legolas52 (talk • contribs) 04:35, 23 June 2011 (UTC)

Try CTRL+TAB, CTRL+SHIFT+TAB, CTRL+PGDN, CTRL+PGUP. You can make ⌘+` mapped to any of these. ¦ Reisio (talk) 06:57, 23 June 2011 (UTC)

On my Ubuntu set up: CTRL+ALT+LEFT or CTRL+ALT+RIGHT cycles through the workspaces; ALT+TAB cycles through the windows in the current workspace (minimised windows stay minimised but still have a place in the cycle); CTRL+TAB cycles through the tabs on the currently active window. Astronaut (talk) 12:38, 23 June 2011 (UTC)

Torrents

My torrent is apparantly downloading, but olny 6.5% has been done and it isn't making any progress after that. Its ETA displays the infinity symbol. Do I have to wait some more or move to a different location or country to get more data? What are ways to speed up a torrent download, or at least not make its ETA be infinity? 72.235.230.227 (talk) 05:35, 23 June 2011 (UTC)

Usually indicates that the only person/s who were seeding it are not presently online or available. If you leave it attempting to download eventually they'll probably get back online, though eventually many torrents do "die" (lose all seeders). Most likely the same time tomorrow you'll get similar download speeds. ¦ Reisio (talk) 07:00, 23 June 2011 (UTC)

Depending on your torrent program, you can usually tell how many complete copies there are on the network by clicking around a bit. If it is less than 1, you won't be able to complete the download unless more seeders come online. Starting up torrents that have very low numbers of seeders is a recipe for stalled torrents. --Mr.98 (talk) 14:26, 23 June 2011 (UTC)

Maybe your peers or peer don't have the complete film either, and will never have, since new downloaders just pass around the pieces that they have. No need to speed torrents up, just go for healthy torrents; they'll give you at least 200 kb/s download rate. Wikiweek (talk) 14:37, 23 June 2011 (UTC)

MS Outlook 2007

I have just bought a new home computer and installed Outlook 2007. I have set up mail accounts exactly as they are already set up on my office computer. This seems to work perfectly well in terms of receiving incoming mail. However, whenever I try to send an email it immediately bounces back to me as undeliverable. I get the following error message: 553 sorry, that domain isn't in my list of allowed rcpthosts. I am hopelessly non-technical. Can anyone explain in words of one syllable how I can fix this problem? Thanks for any help. Maid Marion (talk) 09:38, 23 June 2011 (UTC)

If (as seems likely) you're using your work's email servers then they may be configured so as only to allow mail to be sent from certain IP addresses, so as to prevent spammers and other evildoers using them as SMTP relays. I'd suggest asking your IT department for advice on how to get around this. Edit: Thinking about it a bit more, the details of my answer may be wrong, but I still think the advice of asking the IT dept is valid. AndrewWTaylor (talk) 10:01, 23 June 2011 (UTC)

Thanks for trying Andrew, but there is no IT department. I am just a solitary individual, working sometimes from home, sometimes from a tiny office. The server that hosts my email and website is provided by a third party - I just pay an annual rental for this. Does your answer mean that I need to contact the outside third party? Problem with this is that I am not a high priority for them and I may get no response. Any simpler solution possible? Maid Marion (talk) 10:21, 23 June 2011 (UTC)

Googling an error message is normally a good way to get answers. You could have a look at these[1][2][3][4][5] There are a variety of possible causes, and it will depend on your mail server and other settings. One common cause is that you may have configured your email settings incorrectly in Outlook.

Most ISPs and web hosting company provide extensive online help pages or forums that you can search or post to. You should certainly try emailing them; many use semi-automated systems to respond to emails, so they may reply by pointing you to their website or other useful information, even if you do not get a response from a human being. --Colapeninsula (talk) 10:56, 23 June 2011 (UTC)

Many thanks Cola. Those links provide a mine of information. I will try their suggestions when I get home this evening. If they don't work, I'll be on my knees again asking for further help tomorrow! Maid Marion (talk) 11:09, 23 June 2011 (UTC)

In my experience the majority of Outlook outgoing e-mail problems come from issues with the outgoing server port or SSL settings. First thing I'd try is to set the outgoing server port to 587 or 465 (try both). Accounts>Your email account>more settings. Depends on if your account needs SSL or not but many ISP's are blocking port 25 these days. That setting can be affected by who you are using for an ISP. The SSL less so, but it will still be worth trying to adjust the outgoing SSL settings as well. RxS (talk) 13:50, 23 June 2011 (UTC)

Given the fact that you get a proper error message, firewall or port filtering does not seem to be an issue. You can try setting the SMTP port to 587 and to enable authentication, but this will only help if your work ISP has actually configured their outgoing email server (SMTP) to accept authenticated cnnections from users that are not directly connected to them. A lot of ISPs will not bother setting things up that way. As a spam prevention measure, most SMTP servers only allow IP addresses of their own customers to send mail through them. So when at work, you should use the work SMTP server. At home, you should set the SMTP server to the one provided by your home ISP. Unilynx (talk) 06:12, 24 June 2011 (UTC)

Many thanks to all of you - the usual fantastic Wikipedia response. The problem is now solved. I followed one of the suggestions in Cola's links and simply checked a box on my outgoing server settings saying 'Use same settings as incoming server'. It worked like a charm. Thanks again everyone. Maid Marion (talk) 10:03, 24 June 2011 (UTC)

Secure VPN + Insecure (W)LAN

If you want to connect to the Internet using a (W)LAN that you don't trust, would a secure VPN make it considerably secure? Or would it always be possible for an attacker controlling the (W)LAN (or some link above that) to pretend he is your VPN - forwarding all traffic passing through him? Wikiweek (talk) 14:34, 23 June 2011 (UTC)

When you sign up for a VPN they send you their cryptographic certificate and on subsequent connections your VPN client verifies the identity of the VPN using that. With that working properly, a man-in-the-middle attack wouldn't succeed. The danger point is that initial key exchange. For that you most often rely on public SSL certificates which your browser verifies against the SSL certificate authorities that it knows about a priori. Good VPN providers go to great lengths to make sure you get the correct certificate and not one that's been altered in transit - if memory serves the last time I signed up for a VPN they read the certificate fingerprint to me (in hex) over the phone. This isn't foolproof (certificate authorities can, in theory, be compromised, for example) but it's much more elaborate than simply putting a fake VPN inline between you and the real internet. -- Finlay McWalter ☻ Talk 14:42, 23 June 2011 (UTC)

BrowserChoice.eu - does it really work like this?

This isn't really a problem as such: more a peculiar thing that I wonder if I've understood correctly.

I've recently had to completely wipe my hard-drive and start again from scratch. So, I've got my old copy of Windows XP and am slowly going through the many, many critical updates in sequential order. One of these is the Browser Choice thing, and I make my browser choices, none of which are Internet Explorer. All seems well, and all trace of Internet Explorer seems to be gone.

But then, I go to clean my start-up folder (it comes preloaded with things like Messenger), and notice BrowserChoice.exe, which I unselect. When my computer restarts, all the Internet Explorer shortcuts are back and an Internet Explorer folder containing (among other things) the connection wizard and Internet Explorer itself has appeared. The folder cannot be deleted, because something in it is too important. If Internet Explorer is deleted, it recreates itself by the time you look in the folder again. The shortcuts can be redeleted, but are put back in all their places when you restart. When I reselect BrowserChoice.exe in the start-up folder, this behaviour stops and Internet Explorer again appears to have gone. Except that, when the only browsers I had chosen were Firefox and Opera, if I click on the 'check for updates' thing in the Security Centre, it uses Internet Explorer (which it otherwise pretends has been removed) to open the webpage. Once I installed Maxthon 3 (which uses the same engine (?) as Internet Explorer), it used that instead.

So, my understanding is that, in order to comply with the directive on provided browser choice, rather than providing a patch which deleted Internet Explorer in any way, Microsoft wrote a patch that put an exe in my start-up folder, which runs every single time I start my computer, to supress Internet Explorer from restoring all the shortcuts, and somehow hides Internet Explorer, while leaving it installed and available to the system to open a specific webpage. Is this accurate? Is it actually impossible to delete Internet Explorer from Windows XP?

And, if Internet Explorer is somehow completely embedded into the system, am I opening myself up to any problems if I don't download and install the various patches for Internet Explorer which the system keeps offering me, even after I selected not to be told about them again? I'd assumed I wouldn't need them, since I don't have or use Internet Explorer, but if it's inextricably twisted into everything else, I wonder if there will be unfortunate consequences of not updating it. 86.164.66.52 (talk) 18:44, 23 June 2011 (UTC)

The bulk of Microsoft's web browser is a GUI widget that can be used by any application. It is technically possible to delete it, but not useful because it breaks too much software. You can probably delete iexplore.exe, which is a wrapper around the widget, but you'll save hardly any disk space that way. It makes more sense to just delete the shortcuts and forget that it's there, just like the the hundreds of other small utility programs that you never use. You do need to install security updates to "Internet Explorer" because they are really updates to the browser widget.

I've never encountered BrowserChoice.exe, which is apparently a fairly new, Europe-only thing. I've never noticed IE shortcuts being automatically recreated, but I'm not sure I've ever tried to delete them. -- BenRG (talk) 00:04, 24 June 2011 (UTC)

This Technet blog entry from Microsoft explains what it does. It doesn't say it uninstalls Internet Explorer. Astronaut (talk) 11:43, 24 June 2011 (UTC)

Thank you, these were helpful answers that told me what I needed to know. I'm glad I poked around! I don't quite understand how Internet Explorer is a wrapper on a GUI widget, given what our article on GUI widget seems to describe, but I can understand it being a generic bit of software used by lots of programs. So, thanks muchly. 86.164.66.52 (talk) 16:20, 25 June 2011 (UTC)

Restarting the display in Linux

Hello. I have two questions:

1. I'm running Debian Linux 6.0 on one of my computers. I have it set to not run gdm on bootup, so I boot right to the terminal and then run startx if I want to work in Gnome. That's been working fine until recently; now when I run $startx, it cuts to a screen that is completely blank except for a cursor and doesn't display anything no matter how long I wait. Even odder: I ran #gdm as root, which is supposed to bring up a login screen (but the same thing: blank screen with a cursor). Without seeing anything, I typed in my username, password, and hit enter, Alt+F1'd back to the terminal, ran ps aux, and saw that all the processes where running in Gnome under my uid indicating a successful login, even though the screen is blank. Is this problem easily corrected? It seems that everything is working okay except actually displaying the desktop on the screen.
2. Since I couldn't logout of the desktop since I could not see it, I killed all the processes affiliated with Gnome at the terminal. When I Alt-F7'd to check that the mouse had disappeared and that there was no trace of Gnome, the screen froze. It's frozen on the old ps aux listing and won't let me change terminals (or do anything, for that matter). I connected with PuTTY over SSH, logged in, and everything is working fine. I logged out my frozen session through PuTTY, but the screen is still frozen. I tried Alt+F'ing to a different terminal, and even though it was frozen, I typed my username and password, and called ps aux on PuTTY and it confirmed the login—despite the frozen screen—was successful. So, is there any way to restart or resynchronize whatever is responsible for displaying the terminal to screen?

PS I'm running some lengthy processes on my Linux box that I'd rather not have to shut it down and re-run them. That would be okay if it's necessary, but I figured I'd take the time to learn a little more about Linux, too, since it seems the only problems I'm having are with the display, which may be easily fixable. Thanks!--el Aprel (^facta-_facienda) 21:52, 23 June 2011 (UTC)

http://webchat.freenode.net/?nick=brokenX&channels=#debian ¦ Reisio (talk) 22:58, 23 June 2011 (UTC)

Samsung Galaxy S II release date in China?

Can someone help me find the Galaxy S2's China release date? I'm having some trouble... The Masked Booby (talk) 22:30, 23 June 2011 (UTC)

Laptop design

Hello, why is it that new laptops tend not to have a screen that locks into the keyboard when closed ? The screen just sits loosely on it. — Preceding unsigned comment added by 41.141.77.57 (talk) 23:55, 23 June 2011 (UTC)

It isn't clear to me what value such a lock would have -- and if you had one and it jammed, you'd have a problem. Looie496 (talk) 00:39, 24 June 2011 (UTC)

Apple's design aesthetic is the actual answer to your question. ("why is it that new laptops tend to not have a screen that locks into the keyboard when closed".) --188.29.15.168 (talk) 01:20, 24 June 2011 (UTC)

Because without a lock, or some sort of springy firmness the two halves rattle against each other when closed.

I don't know know why they don't have latches anymore, but I suspect that it's a combination of better hinges and style. APL (talk) 01:29, 24 June 2011 (UTC)

Eh, in my experience, the hinges tend to be so bad you don't need the lock - you have to use more than one hand to open them regardless. The answer is, of course, that it is the current trend. The bulk of electronics are not designed to consumers' wants, but to consumers' present expectations (which trend low). ¦ Reisio (talk) 02:55, 24 June 2011 (UTC)

The hinges aren't "bad", they're intentionally stiff, so the laptop will stay as opened or closed as you left it. StuRat (talk) 05:03, 24 June 2011 (UTC)

Yeah, they're bad. ¦ Reisio (talk) 05:22, 25 June 2011 (UTC)

From my laptop owning experience the latch-mechanism is one of the weaker/less reliable parts of the construction. My current laptop uses magnets to hold the lid closed. This works extremely well and is (in my eyes at least) 100% better than any latch mechanism. ny156uk (talk) 05:04, 24 June 2011 (UTC)

Just to illustrate this, Apple's iBook G4s had hinge locks which, if broken, necessitated replacing the entire top frame of the laptop, which was neither a cheap nor an easy piece to replace. (Or using velcro or other ersatz solutions.) --Mr.98 (talk) 12:50, 24 June 2011 (UTC)