I want to Uninstall everything from my system except the OS itself. In fact I want to factory reset my system.   Current version I am using is 18.4
I want to save the list of packages that have installed. I figured it might be the best to list all and diff it with the default set.  Edit: Clarification: I don't want to get the list of installed packages that are installed at the moment. Rather I want to get the list of packages that I added since the default install.
Are Playstation 4 games locked to a certain region? This question has been asked before, but it was for PS3 and Xbox 360 and was asked August 2010. This time around my question goes specifically to PS4, since I'm moving from Mexico to Europe and I was wondering if the European games will run in my console or if I'll have to buy a new one. I never thought of this before (which is why I never paid attention if it was mentioned in reports or specs of the console) and the research I did wasn't too helpful. Story where someone gets disconnected from computers for cybercrime I read a short (in the range of 5-20 pages) science fiction story a while ago, and can't remember the title of the story or its author at the moment.  The basic story is that of a super-savvy computer hacker who got all of his knowledge of computers removed from his brain, temporarily (one year?) for cybercrime, including (IIRC) some form of identity theft, and is released into the public without any jail-time or anything. This is very hard on him, for this future-Earth relies heavily on highly interconnected computers for basic and daily needs. This is not immediately clear at the start of the story, but it becomes apparent after a little while.  Part of the story includes the main character (I don't remember if he is granted a name in the story) wanders into a cafe or a bar, and is invited to play a game of digital, . He has to turn down the invite, though, because he doesn't know and is blocked from knowing how to use computers. He also really doesn't want the other characters to know this, because apparently having your computer knowledge removed from your brain for cybercrime is a major stigma in that society. The character also has difficulty using his (futuristic equivalent of a) credit card, as that also requires some computer knowledge.  Any ideas? In what order should I watch the various Stargate TV Series? I am unfamiliar with the (multiple) Stargate shows and films, other than the movie which I saw a while ago. I want to try watching the series to see if it is something that I like.   What are the non-subjective facts about the series (without spoilers) that I should be aware of when figuring out which series to start with, for example the original airing order of the series, chronological order of the series, frequency of references to a series other than the one that I'm watching, etc. Akhil showed that the  is the same as the continuum, using as a step the observation that continuous functions that agree at rational points must agree everywhere, since the rationals are dense in the reals.  This isn't an obvious step, so why is it true? So, I'm running linux Mint (but I guess the same applies to Ubuntu) and as is common knowledge, their TeX distribution tends to be slightly outdated. Now I can't have none of that and decide to install it with the install-tl from the TeXlive homepage. Somehow, I cannot install it as a normal user (this I find normal as it is installing in the root directory), so I proceed to install TeXlive   sudo perl ./install-tl   and add the paths to .bashrc. All is well and my TeXlive installation works. Except for the texhash option. Running it as a normal user is no problem, except that I installed TeXlive as root, and so running texhash as normal user doesn't do anything (directory not writable. Skipping...). No problem I think, I'll just do it as root. But somehow texhash isn't installed for root.  Now, texhash is somehow connected to updating the directory tree, but I don't really know what it does. I use it on my ~/texmf/ folder to add my packages to a global path (I think), but when looking at info for this question I see in a comment for  question that this is apparently not needed, though I don't understand what I'm to do now.  So if I'm not adding new packages from CTAN or updating, I really don't need texhash and all is good?   To summarize: I'd like to know:    Why should I need texhash? Can I avoid installing as root on linux Mint/ubuntu ( they say you don't have to be root, that it's even discouraged)? Should I somehow install texhash for root?   I realize this might be a vague question at best, but I didn't find an answer I readily understood, so I'd appreciate any thought on this. Compiling LaTeX document empties .bbl file I'm trying out biblatex for the document I'm compiling, using the biber backend on my miktex distribution. Everything, including biber, should be up to date, assuming the MiKTeX repository currently holds the latest versions of everything.  This is what the biblatex documentation (p. 101) says about how often I have to run biber to update my .bbl file:     Whenever a reference to a work which has not been cited before is   added, this procedure must be repeated. This is also the case if the   last reference to a work which has been cited before is removed   because some citation labels may change in this case.   So if I make changes to my document (which is a very common activity in the process of writing a document), but leave the citations unchanged, I should not have to re-run biber before compiling the changes. However, every time I compile my document, regardless of the compiler or documentclass, the .bbl file is emptied. Consequently, the next time I compile the document without running biber, the bibliography is removed (seeing as the .bbl file contains nothing), and all my citations are broken. For this reason, I have to run biber before every time I compile the document, which largely counters the benefit of externalizing the bibliography in the first place.  How can I make the compilers stop overwriting my .bbl file and make everything behave as described in the biblatex manual?  Upon investigating the contents of the auxiliary files, I found that the .bbl file (after running biber, before compiling) begins with the following lines:  % $ biblatex auxiliary file $ % $ biblatex bbl format version 2.3 $   Does the biblatex version 2.8 still mark the .bbl files as version 2.3? If not, could this be the problem? And if so, why does my 2.8 version of biblatex (partly) behave as version 2.3?  Any help solving this problem would be much appreciated. I read the following dev email  and when i read this part:  Note that this does not completely remove the ability for extensions (e.g. Dropbox) to add emblems programmatically by using the libnautilus-extension library, just the user-added emblems from the properties dialog/emblems sidebar.   There is ability to bring emblems programmatically. So, How can i use libnautilus-extension library to add some emblems like Dropbox does? Or is there any tweak tool for this? " java.lang.IllegalArgumentException: uri.getScheme() == null! " error using JavaFX to play audio Spacing before and after section titles I know this subject has been mentioned before, but I'm still having a problem in creating a space under a section title. I used the titlesec package and then tried using the command \titlespacing{\section}...  This is my code. Can anybody help?  \documentclass[10pt]{book} \usepackage[utf8]{inputenc} \usepackage{fullpage} \usepackage[compact]{titlesec} \usepackage{setspace} \usepackage{sectsty} \chapterfont{\huge} \sectionfont{\Huge} \begin{document} \chapter*{Kapitel 1} \section*{Einleitung} \begin{large} \subsection*{1.1 Motivation} Ubuntu Wifi drivers not working after getting update How to estimate camera sensor size? I am using a smartphone for capturing photos and I need to estimate the camera sensor size (mm*mm). I have the resolution (in pixels) and the focal length (in pixels). I can also measure the size of any stationary object and its distance w.r.t the lens. Basically, I don't have a pixel-to-mm metric for any of the above parameters that I can use. Is there any way I can calculate that to estimate sensor size? Comma as decimal marker with siunitx (Spanish usage) I'm using siunitx to input some big numbers and units in my document.  Is there a way to make the output of \num{3.14} be "3,13" instead of "3.13"? In Spanish, we use the first one. PDF Editing in PHP? Does anyone know of a good method for editing PDFs in PHP? Preferably open-source/zero-license cost methods. :)  I am thinking along the lines of opening a PDF file, replacing text in the PDF and then writing out the modified version of the PDF?  I have programmatically created PDF files in the past using FPDF, but found it a little unwieldy at times. I try to initialize an array in bash-4.2 next way:  ring=() ls -las | tail -n +4 | while read line &gt; do &gt; ring+=("$line") &gt; echo ${ring[-1]} &gt; done 3924 -rw-r--r-- 1 username group 4015716 Mar 23 15:14 script.jar 4 -rw-r--r-- 1 username group 9 Feb 29 12:40 rec.lst 5541 -rw-r--r-- 1 username group 5674226917 Mar 28 15:25 debug.out 8 -rw-r--r-- 1 username group 6135 Mar 25 12:16 script.class 8 -rw-r--r-- 1 username group 6377 Mar 25 11:57 script.java 8 -rwxr-xr-x 1 username group 4930 Mar 8 15:21 script-0.0.0.sh 8 -rwxr-xr-x 1 username group 6361 Mar 28 15:27 script-0.0.1.sh echo ${ring[0]}  echo "${ring[0]}"  echo "${ring[@]}"   What is wrong, why i get empty array after the finish of the loop? NSString question - rangeOfString method Making holes in an object using an image as a reference I have an object already created in blender, a tree, or a human, or a pipe.. and I need this to be drilled with multiple holes.   The holes are painted in an image, that is, it is an image that has a repeating an images pattern (they can be circles, squares, or any form).  Here are some examples for drilling-pattern: Since 17.10 I got familiar with Wayland and I really need the per-monitor-scaling!  How can I start a wayland session after dist-upgrade to Bionic? There is no option in GDM available out-of-the-box.  I do not see what is described as     The Wayland session will still be available, pre-installed How to know (in GCC) when given macro/preprocessor symbol gets declared? Suppose I have #define foo in various header files. It may expand to some different things. I would like to know (when compiling a .cc file) when a #define is encountered, to what it will expand, it which file it is and where it got included from.  Is it possible? If not, are there any partial solutions that may help?  Feel free to add comments with clarification requests.  Edit: current answers seem to concentrate on the case when there is one #define and I just want to jump to definition or know what the definition is. That's the simple case and yes, your solutions work. But when I have the same #define in different files, and want to know which one kicks in first, none of these techniques is useful. Okay, I actually used #warning carefully to find the right place. But this requires much work. Why is there no 32 bit ISO for the new Ubuntu 18.04? I need a robust and simple way to remove illegal path and file characters from a simple string. I've used the below code but it doesn't seem to do anything, what am I missing?  using System; using System.IO;  namespace ConsoleApplication1 {     class Program     {         static void Main(string[] args)         {             string illegal = "\"M&lt;&gt;\"\\a/ry/ h**ad:&gt;&gt; a\\/:*?\"&lt;&gt;| li*tt|le|| la\"mb.?";              illegal = illegal.Trim(Path.GetInvalidFileNameChars());             illegal = illegal.Trim(Path.GetInvalidPathChars());              Console.WriteLine(illegal);             Console.ReadLine();         }     } }