I received a machine (Ubuntu 12.04 server) from a coworker when he left the company. I created my own user as sudo/admin and used the machine for months via SSH. After rebooting for the first time since I was given the machine, I discovered that my user and everything I installed were missing. My user wasn't in the /etc/passwd file and the /home/myuser directory was missing. When I recreated the user and reinstalled everything, I didn't get any suspicious errors.  I suspect that I might have been in a snapshot/jail/container environment the whole time before rebooting, but how can I tell?
Unsolved mystery - I was given a coworker's Ubuntu 12.04.1 LTS machine and set up my own (sudo/admin) user on there from the command line. I switched to my user (from his sudo/admin user) and confirmed everything was okay using the groups command and the /etc/passwd file looked great. After months of everything working perfectly, a power outage shut down the machine for the first time since I inherited it.  After booting, my new user disappeared. It's not in the /etc/passwd file and there is no entry in the /home directory. I created the user the same as I did before, and there were no errors to indicate that the user still existed.  What happened?  As requested, here is the output of   olduser@machine:~$ ls -lait /home  total 16  3408126 drwxr-xr-x 2 newuser newuser 4096 Nov 20 10:28 newuser  3407873 drwxr-xr-x 4 root root 4096 Nov 20 10:28 .  3407874 drwxr-xr-x 36 coworker coworker 4096 Nov 20 10:00 bvillupu  2 drwxr-xr-x 26 root root 4096 Oct 3 2012 ..  3408259 lrwxrwxrwx 1 root root 44 Aug 9 2012 .directory -&gt; /etc/kubuntu-default-settings/directory-home
Multiplication in Permutation Groups Written in Cyclic Notation Intro  I'm working on a lightweight package that allows you to put any content (typically LaTeX code) in an environment, then use that content multiple times, each time scanned separately, so you can use it both as verbatim output and interpreted as LaTeX.  Its main purpose is to typeset LaTeX code and its 'result' side-by-side; useful for documenting TeX packages without having to copy/paste code. But it has other purposes as well.  After experimenting with \scantokens until I gave up in tears, I arrived at the filecontents environment, which almost solved my problem singlehandedly!  The Problem  The problem is, when reintroducing filecontented code through \input, LaTeX adds an implicit newline at the end, which translates to whitespace that I can't seem to get rid of.  I've seen many semi-related questions floating around, with answers employing techniques like:   reading a file line-by-line, using \everyeof in some clever way, playing with \endlinechar or using packages such as catchfile   but none of them provides a clear answer to the following question:  The Question  How can I \input a file without getting the implicit newline?  Minimal Working Example  \documentclass[margin=1mm]{standalone}  \usepackage{filecontents}  \begin{filecontents*}{tmp.tex}     \LaTeX{}\end{filecontents*}  \begin{document}     \fbox{\input{tmp.tex}} \end{document}     Note the extra whitespace to the right of the box.  Note also that I'm definitely not adding any explicit whitespace. Even a manually produced file (so, not using filecontents) with no newlines at all exhibits the same problem. "Above"/"below" before/after a noun I have seen sentences similar to the following:  (1) See the reference above. (2) See the reference below.  And,  (3) See the above reference.  But not,  (4) See the below reference.  Are all these forms acceptable? Which is/are preferred in formal writing? From what time I've spent with threads in Java, I've found these two ways to write threads:  With implements Runnable:  public class MyRunnable implements Runnable {     public void run() {         //Code     } } //Started with a "new Thread(new MyRunnable()).start()" call   Or, with extends Thread:  public class MyThread extends Thread {     public MyThread() {         super("MyThread");     }     public void run() {         //Code     } } //Started with a "new MyThread().start()" call   Is there any significant difference in these two blocks of code ? I have a sentence that contains a number of long dataset names. I would like to allow LaTeX to break these names at certain positions that I would like to specify somehow just like I can use \- to allow a word break with hyphenation. But: I would like LaTeX not to insert a dash (which could be mistaken as belonging to the dataset name). How can I do this?   (Something similar is realized in the url package so I guess I could just read that code :) I would not like to use the url package here to be able to make a syntactical (and typographic) difference between urls and datset names.) What if I run a virus/trojan Windows EXE on Ubuntu with Wine? How to solve differential equations of the form $f'(x) = f(x + a)$ What could one do to find analytic solutions for $f'(x) = f(x + a)$ for various values of $a$?  I know that $c_1\sin(x + c_2)$ is solution when $a = \frac{1}{2}\pi$, and of course $c_1e^x$ when $a = 0$.  For instance, is there a function satisfying $f'(x) = f(x + 1)$?  What about negative or imaginary $a$?  Is there possibly a generalization? sda1 -> Windows XP  sda2 -> Windows 7 sda3 -> Data Partition   I have created 4 primary partitions, I have 7xx GB left, how can I create one more partition? How can you move a document with its version history to a new library? Here's the scenario:  2 document libraries Both contain multiple documents The documents have multiple versions  When I copy a document from library A to Library B using the Content and Structure tool from Site Settings, my versions do not carry over. I'm trying to merge the two document libraries into one, but I want to retain the versions. Do you know of a way to complete this without third party tools or custom code? I've heard suggestions of using Explorer View copy and paste, SharePoint Designer and List Templates, but I'm not sure any of those will carry version info. Modern solution For modern SharePoint experiences, use Move To. Update 4/24/2018: There's a new solution in Office 365. You can now select a file or group of files in the modern experience in OneDrive or SharePoint and select Move to. A file or group of files moved this way will retain version history. Update 6/6/2021: As @KJH mentioned in a comment, you may not see the modern experience unless you . Also, there's more detail now in the Microsoft article . Is there an analytic function $f$ on $B(0,1)$ the open ball with radius 1 such that $f(1/n)=e^{-n}$ for $n=2,3,4,...$? Is there an analytic function $f$ on $B(0,1)\subset\mathbb{C}$ such that $f(1/n)=e^{-n}$ for $n=2,3,4,...$? I know the following doesn't work:  Let $g(z)=\exp(-1/z)$. Then, $f=g$ on a sequence with a limit point in $B(0,1)$ and so $f=g$ on $B(0,1)$. Since $g$ is not $\mathbb{C}$-differentiable at $0$, neither is $f$ and so such a function cannot exist.  This is not the solution because you cannot use the identity principle with a non analytic function like $\exp(-1/z)$ is not analytic at $z=0$. Any help using the identity principle another way? Maximal Ideals in Ring of Continuous Functions Dummit and Foote, 7.4.33(a): Let $R$ be the ring of all continuous functions $[0,1] \to \mathbb{R}$ and let $M_c$ be the kernel of evaluation at $c \in [0,1]$, i.e. all $f$ such that $f(c) = 0$. Show that if $M$ is a maximal ideal in $R$ then $M = M_c$ for some $c$.    I am aware of proofs that use the compactness of $[0,1]$; however I have been told that a simpler proof exists using only the isomorphism theorems for rings along with basic facts about ideals. I have tried on my own to prove it this way but still have no success; is it possible?  (My attempts go something like: since $M$ is maximal, the quotient ring $R/M$ is a field. Then it would be nice to use the fact that $R/M$ has no zero divisors, but I can't quite make it work. Alternatively, consider $M \cap M_c$.) Limit of a sequence defined by recursive relation : $ a_n = \sqrt{a_{n-1}a_{n-2}}$ Forcefully update to new windows Gnome Panel becomes fully transparent when window is not maximised! Film where aliens looking like humans are waiting in an airport closed due to snowstorm I saw the movie 6 - 7 years back on cable tv, from the looks of it it seemed to be made in the late 1990's or early 2000's. Unfortunately I could not see the complete movie. The story goes like--   Some people are waiting at a small airport because snowstorm activity has cancelled all flights in and out. There are two children in the group as well (one boy and a girl). Somehow they discover there are aliens looking like humans among them. They decide to check passengers through baggage scanners (checking the skeletal structure via x-ray). They find and kill 2 aliens.   and the big twist:      5. They then realize the two children are also aliens.   any ideas what the name of the movie is ??? How can I embed a View inside a content of a node? How can I embed a view inside a content of a node in Drupal 8?   I found something similar, for example in the question about "" or the  module, but it is all for Drupal 7.  I tried with an Entity reference field pointing to a View but it display only a label and from the Manage Display tab I can choose only from Label and Entity ID. I need something like the "Rendered entity" option that is present on Entity reference fields pointing to other nodes. How to disable captive portal detection? How to remove exclamation mark on Wi-Fi or signal icon in Lollipop? I need to use an alias in the WHERE clause, but It keeps telling me that its an unknown column. Is there any way to get around this issue? I need to select records that have a rating higher than x. Rating is calculated as the following alias:  sum(reviews.rev_rating)/count(reviews.rev_id) as avg_rating Why does shell Command Substitution gobble up a trailing newline char? As per the following example, and as in  In bash, where has the trailing newline char gone?, I want to know "why" it happens    x="$(echo -ne "a\nb\n")" ; echo -n "$x" | xxd -p  # Output is: 610a62  # The trailing newline from the 'echo' command #   has been "deleted" by Command Substitution   I assume there must be some very significant reason for a shell action, namely Command Substitution, to actually delete some data from the command output it is substituting... but I can't get my head around this one, as it seems to be the antithesis of what it is supposed to do.. ie. to pass the output of a command back into the script process... Holding back one character seems weird to me, but I suppose there is a sensible reason for it...  I'm keen to find out what that reason is... Another way to write least prime factor.