In older days that I used to run Fluxbox, in order to be able to shutdown my computer I need to allow passwordless root access via sudo to the command  shutdown by running viedit and doing the appropriate changes.  Also when the computer shutdown my computer is perfmormed over terminal via the shutdown command, root access is needed.  But modern Desktop GUI implementations such as KDE/GNOME/LXDE/XFCE etc etc the shutdown is by default rootless (no root password is required). And I wonder how theese desktop GUIS manage to "perform"/notify the kernel that the computer is shutting down without the need of root access?
I understand that clicking "shut down" from the menu that comes up on clicking the cogwheel triggers the following command to be executed:  dbus-send --system --print-reply --dest=org.freedesktop.Hal /org/freedesktop/Hal/devices/computer org.freedesktop.Hal.Device.SystemPowerManagement.Shutdown   However, when I execute this command on a terminal, I get the following error:  Error org.freedesktop.DBus.Error.ServiceUnknown: The name org.freedesktop.Hal was not provided by any .service files   Is it because 14.04 uses some other service for shutting down, or am I doing something wrong?    Note: This question is in follow-up of:
In-universe explanation for single line of planetary entry/departure in Star Wars Running own executable on Android shell I need a specific command line tool and I have made a C program in my Linux shell. I have compiled the program with an ARM cross-compiler. I have then moved the program into the Android file system and tried to run it.  The output is permission denied.  What do I have to do, in order to run my own compiled programs in Android file system? MacBook Air: What taking up all my hard drive space How to create a site in a sitecollection on a remote SPServer using C# I am currently trying to write a Dynamics CRM 2011 plugin that creates a new SharePoint 2010 site (within an existing site collection) for every account that is created. I have the code for creating a library, which uses the following methods:          private static ClientContext CreateSharePointConnection()         {             try             {                 Uri spSiteUrl = new Uri(Constants.SharePointSiteName);                 using (ClientContext spcontext = new ClientContext(spSiteUrl))                 {                     spcontext.Credentials                         = new System.Net.NetworkCredential(Constants.UserName                             , Constants.Password, Constants.DomainName);                     return spcontext;                 }             }             catch (Exception ex)             {                 throw new Exception("SharePointMethods.CreateSharePointConnection (General Exception: "                     + ex.Message + ")");             }         }  private static void CreateDocumentLibrary(ClientContext _clientContext             , string _documentLibraryName, string _documentLibraryDescription)         {             try             {                 Web web = _clientContext.Web;                 _clientContext.Load(web);                 _clientContext.ExecuteQuery();                 ListCreationInformation lci = new ListCreationInformation();                 lci.Title = _documentLibraryName;                 lci.Description = _documentLibraryDescription;                 lci.TemplateType = 101;                 List newDocumentLibrary = web.Lists.Add(lci);                 newDocumentLibrary.ContentTypesEnabled = true;                 newDocumentLibrary.Update();                 _clientContext.ExecuteQuery();             }             catch (Exception ex)             {                 throw new Exception("SharePointMethods.CreateDocumentLibrary('" + _documentLibraryName                     + "') (General Exception: " + ex.Message + ")");             }         }   So I would like to write a method CreateSite instead of CreateDocumentLibrary. However, all examples I can find on the web for programmatically creating a Site are using SPSite, SPWeb, etc. Something like this:  private static void CreateSite(string _siteName, string _siteDescription) {     try     {         SPSite site = new SPSite(Constants.SharePointSiteName);         SPWeb web = site.OpenWeb();         SPWebCollection wc = web.Webs;         string siteTemplate = web.WebTemplate;         wc.Add(Constants.SharePointSiteName, _siteName, _siteDescription, 1043, siteTemplate, true, false);     }     catch (Exception ex)     {         throw new Exception("SharePointMethods.CreateSite('" + _siteName             + "') (General Exception: " + ex.Message + ")");     } }   However this is NOT a solution for my problem, because the SPSite, SPWeb, etc. only work on the local machine and I want to create a Site from a remote (in my case CRM) server. Anyone got an idea how to solve this.  PS: Code might still contain memory leaks, so please be carful when you use it for production purposes! Stars and pins are retained when chat messages are moved! Windows vs Linux Local Time? Ever since I started using Linux in dualboot with Windows I noticed that when I rebooted the machine, the time on the other OS was wrong, e.g. it was 12:00 on Linux, then I rebooted and on Windows it was 18:00, and when I checked the BIOS, the RTC was set to 18:00. Since my timezone is -06:00 CST I assume Linux just sets the RTC’s time to UTC and re-calculates the time based on the timezone, whereas Windows just sets the RTC to the local time. Both use the same NTP server to sync the time.  The question is, which one is doing the right thing? On which one should I set the timezone setting to UTC in order to have the right time on both? If my account is already a member of the administrator group why do some functions on Windows 7 require me to run them as administator? I kind of thought that was implied? How to inject keystrokes via a shell script? I'm trying to inject keystrokes into the input daemon so as to simulate typing from a Bash script. Is this possible, and if so, how can I make it happen? Proof of inequality $2(\sqrt{n+1}-\sqrt{n}) < \frac{1}{\sqrt{n}} < 2(\sqrt{n} - \sqrt{n-1})$ using induction Prove that $2(\sqrt{n+1}-\sqrt{n}) &lt; \frac{1}{\sqrt{n}} &lt; 2(\sqrt{n} - \sqrt{n-1})$ if $n \ge 1$ using induction.  Can someone help me with this problem please. Base case is easily shown, and for the inductive step I know I have to use the inequality for $n\gt1$ to show that it is true for $n+1$, but I am not quite sure how to.   Thanks. C Scanf suddenly stopped reading in values Earlier, I voted to close  as off-topic.  The question has since been closed.  There is an , but it didn't show up in the list when I selected "off-topic".  The options were:   Meta Stack Overflow Server Fault Super User Webmasters Programmers   Questions:   Should Wordpress appear in this list? Are there any other sites that should appear in the list?   Should all non-beta sites appear in that list by default? Tikzexternalize not compatible with Miktex 2.9 abntex2 package Linear Algebra: If $A^3 = I$, does $A$ have to be $I$? Probably a basic issue, but still something that irks me and I can't find an answer online. I want to change the default folder for saving new shapes/processing outputs from &quot;last used folder&quot; to &quot;project folder&quot; or &quot;something in relation to project folder&quot; - is this possible? If so, how can I achieve this? I'm trying to watch for any new output of a log file. Another script (not under my control) is deleting the file then creating a new one with the same name. Using tail -f doesn't work because the file is being deleted. Why do I get a black rectangle instead of my external picture? I write some of my network notes in TeX. I wanted to make a table, and inside it insert an image:   .   I wrote a document:  \documentclass{article} \usepackage[demo]{graphicx} \usepackage{booktabs} \usepackage{array}  \begin{document} \begin{tabular}{m{3cm}m{3cm}m{5cm}} \toprule Configuration for ... &amp; Commands &amp; Topology\\ \midrule PPP: CHAP, PAP &amp; \#sh int se 0/0/0  &amp; \includegraphics[width=4cm, height=4cm]{chappap.png}\\  &amp; &amp; \\ \bottomrule \end{tabular} \end{document}   But instead of my network topology image, I see only this: .   I don't know what is wrong, cause my image is 100% in the same dir, as my *.tex file.  EDIT:  Changed my code as @Jubobs suggested, now everything is as I wanted:  \documentclass{article}     \usepackage{graphicx}     \usepackage{booktabs}     \usepackage{array}      \begin{document}     \begin{tabular}{m{3cm}m{3cm}m{5cm}}     \toprule     Configuration for ... &amp; Commands &amp; Topology\\     \midrule     PPP: CHAP, PAP &amp; \#sh int se 0/0/0  &amp; \includegraphics[width=4cm, height=4cm]{chappap.png}\\      &amp; &amp; \\     \bottomrule     \end{tabular}     \end{document} Limit of the geometric sequence $\{r^n\}$, with $|r| < 1$, is $0$? Player A taps  targeting Player B; its "deals 1 damage to target player" ability is placed on the stack.  Player B gets priority and responds with , targeting Goblin Fireslinger.  Both players pass priority. Snap resolves, and Goblin Fireslinger is returned to its owner's hand.  Does Player B still take 1 damage from Goblin Fireslinger's activated ability?  I know that if the creature had been killed/sent to the graveyard, the ability would still resolve, but I was told recently that because a player's hand is a private zone it couldn't. If anyone could confirm or deny this for me, it would be most appreciated. What does it really mean that telephoto lenses "flatten" scenes? This is another perspective distortion question. I understand that perspective distortion is primarily a function of capture and viewing distance, but I am still working on fully understanding the causes of the "flattening" of scenes that is credited to telephoto lenses.  This seems to refer to our ability to discern the differences in size attributable to differences in distance from the lens for subjects beyond a certain distance from the lens. If this is correct, then is it just that with the longer distance from the subject when using a telephoto lens, this compression happens closer to the foreground, rather than in the mid- or background with a wide lens?  Is it fair to say that the compression effect occurs at a certain distance from the photographer regardless of lens, but the field of view influences how close to the foreground this effect takes place? Can you share any information to help people like me understand this? How do I calculate the power consumed by a lightbulb?