I am preparing a file using shell script and while doing some tests, I added the pause&gt; nul line into my sh file. Then I ran the sh file, but there was a file named nul on the desktop and I can't delete it in any way. What would you suggest me to do? Thank you. Note: I cannot change the name of the file, I cannot move the file to a different folder. I cannot delete the file, I try to delete the file permanently and it comes back again. I cannot open the file. (LSHIFT + RSHIFT + DEL)
I have a Windows XP box (NTFS filesystem) on which I found a file named NUL. I have not been able to remove this file in any usual way. The file appears to be owned by Administrator in the SYSTEM group, unlike any other file in the same directory (the other files are owned by my user id).  How do I get rid of this file? Where did it come from?
How can I prove that     $$1^3+ 2^3 + \cdots + n^3 = \left(\frac{n(n+1)}{2}\right)^2$$    for all $n \in \mathbb{N}$? I am looking for a proof using mathematical induction.  Thanks iOS app in a zombified state What is the difference between a synchronized method and synchronized block in Java? Requested value 'CheckBoxes' was not found There's a weird thing happening with my Windows application. I have created a Sharepoint utility to automate the creation of content-types and site-columns. At a point where I try to get my available fields, I get this error:     An unhandled exception of type 'Microsoft.SharePoint.Client.ServerException' occurred in Microsoft.SharePoint.Client.Runtime.dll   Additional information: Requested value 'CheckBoxes' was not found.   It is throwing an exception at:  ClientContext clientContxt = new ClientContext(clientContext.Url);         clientContext.Credentials = clientContext.Credentials;         Web web = clientContext.Web;          clientContext.Load(web, w =&gt; w.AvailableFields);         clientContext.ExecuteQuery(); //**exception thrown here**   Kindly please suggest what is wrong here? Updating the SubscriberKey on the All Subscriber table through the API I'm trying to update an existing Subscriber in the All Subscriber Table through the API; i've set up the AppId in the App Center and have connected and created Subscribers, but i'm still having issues updating.  What call do I need to be making to do this? These are the ones i've been trying. I have some kind of test data and want to create a unit test for each item. My first idea was to do it like this: import unittest  l = [[&quot;foo&quot;, &quot;a&quot;, &quot;a&quot;,], [&quot;bar&quot;, &quot;a&quot;, &quot;b&quot;], [&quot;lee&quot;, &quot;b&quot;, &quot;b&quot;]]  class TestSequence(unittest.TestCase):     def testsample(self):         for name, a,b in l:             print &quot;test&quot;, name             self.assertEqual(a,b)  if __name__ == '__main__':     unittest.main()  The downside of this is that it handles all data in one test. I would like to generate one test for each item on the fly. Any suggestions? I try to solve this problem. I seems to come close to the end but I can't get the conclusion. Can someone help me complete my proof. Thanks          Show that the polynomial $h(x) = (x-1)(x-2)\cdots(x-n) + 1$ is irreducible over $\mathbb Z$ for all $n\ge1$ and $ n\ne4$.      Suppose $h(x) = f(x) g(x)$, then we must have $f(i)g(i) = 1$ for all $i = 1,2,...n$. So both $f(i)$ and $g(i)$ are $1$ or $-1$. In either case, $m(x) = f(x) - g(x)$ has degree smaller than $n$ and have $n$ different roots ($1,2,...,n$). So we must have $m(x) = 0$. Then $h(x) = f(x)^{2}$. So $n$ must be even. Let $n = 2k$. Because $f(x)$ has degree $k$, there are $k$ values from $\{1,2,...,2k\}$ at which $f(x)$ is $1$ and $k$ values at which $f(x)$ is $-1$.  This is where I got stuck. Hope some one can help me solve this. Thanks. remove numbers from filenames in Mac OS X I have a directory full of files with names in this format (with numbers as the start of each filename):  102_file.txt 104_list.txt 242_another_file.txt   I would like to rename them as follows (i.e. removing the numbers):  file.txt list.txt another_file.txt   Can anyone suggest a way to do this (presumably from the terminal)? Wear a hat multiple times? Why don't the White Walkers take the sea route to Westeros How to rename user folder in Windows 8? When I log in on a Windows 8 machine for the first time with my Microsoft Account (by providing an e-mail address), a new user folder is created:  C:\Users\dzinx_000   In previous versions of Windows, I could choose the name of this folder (it was equal to my username). As I use the commandline often, it is quite annoying to me.    Can I somehow rename it to dzinx?  Does simply renaming the folder break everything? How do I create tools with multiple properties? I'm trying to create an item that can break certain blocks, but also has a colored name in 1.13.2   Here's the command I'm using.  /give iAugust minecraft:shears{display:{Name:"[{\"text\":\"Arcane Shears\",\"color\":\"aqua\",\"italic\":false,\"bold\":false}]CanDestroy:[minecraft:iron_bars]"}}   But it only has a colored name, and it can't break specific blocks. Finding out which app is using the webcam Yesterday I was working on my laptop. Suddenly I noticed that the indicator light of the webcam was on, despite the fact that I wasn't making a video call or using the webcam in any other way at the moment.  It freaked me out.  It freaked me out that some unknown application on my computer was using my webcam without my permission, and possibly sending that video stream to god knows where on the Internet.  In the end, it turned out to be Skype which was in the process of crashing. (Despite me making no calls at the time.) So that story ended well.  But next time I see the webcam indicator light, I want to be ready. I want to be able to know exactly which app is using the webcam so I could destroy it.  Does anyone know how I can find out which app is using the webcam?  (I'm on Windows XP.) Doesn't Matlab work on ubuntu 16.04? Why can't I connect to Pokemon Go via mobile data? It connects to Pokemon Go via wi-fi perfectly fine, but when I try and connect to Pokemon Go via 3G it just gets stuck at the first bar on the loading screen with the eventual pop up saying "Failed to get player information from the server." My 3G connection works perfectly fine with every other app I have, and has been easily able to stream HD videos so I can't see connectivity with 3G being an issue.   It makes even less sense as once connected via wi-fi, the game easily continues to operate via mobile data once I leave the house. However once the app crashes (which it usually does after 15-30 minutes) I try to reload it on mobile data and it gets stuck on the loading screen. If I can find a local free wi-fi spot nearby I can re-connect easily, and then move back onto mobile data.  I've tried removing and reinstalling Pokemon Go and that didn't work. I also reset all my app preferences on my phone and that didn't work.  Not sure if this helps, my phone is a Huawei P8, Android version 5.0.1.  I signed up to Pokemon Go using my Google account. How do I uninstall Ubuntu Wubi? Named parameters in JDBC Is it acceptable to take photos of slides at a conferences for private use? Is it accepted/appropriate to take pictures of presentation slides at conferences for private use?   I am not talking about putting those pictures out in the public afterwards, I know this is illegal without consent of the presenter.    Should it matter, I am talking about math conferences.  And I am asking because I don't see anyone taking pictures. How can I drive 12v LEDs from my Arduino Nano? Background I am building a scale RC helicopter and ordered a bunch of 3mm LEDs to give it some nice navigation and strobe lights which I plan to drive with an Arduino Nano. Problem is that I goofed and didn't notice that the LEDs are 12v until they arrived.  I know that the Arduino Nano can accept 12V on pin 30, but I think the voltage output on any of the &quot;D&quot; or &quot;A&quot; pins is always 5v (correct??). Question If the voltage output of the Arduino pins is 5v, then how can I drive the 12v LEDs using the Arduino, or is it impossible? Terminal command 'login' fails with error message Coming from Mac OS X, there is a possibility for every ordinary user to open Terminal and type in 'login' to change to a different user account.  When I do this with Ubuntu, it provides the following error message:  login: Cannot possibly work without effective root   Is there any way to remedy this?  Which file do I need to edit and with what to enable the use of this command (even for a standard user)?