I used to use "snapshot" command to capture screen shots in the Linux Redhat environment. Is there the same or similar command with ubuntu 12.04 LTS?
I wrote a bash script as below:  #!/bin/bash echo "Enter a file name" read filename import -window root $HOME/Desktop/$filename.png   I expected this script to take a screen shot and save the image with the given filename on my desktop.  Problem:  My Ubuntu terminal is giving error:     import: Command Not Found
How to use Terminal to delete all .svn folders recursively? What command can I type into the Terminal so that I can delete all .svn folders within a folder (and from all subdirectories) but not delete anything else? Opening a file from terminal When we want to open an application or file from the terminal, we type, say,  okular file.dvi   This opens the application, but also shows the status of the application. We cannot close the terminal, because it kills the process. Unfortunately, if you're trying to, for example, create a LaTeX file, you will need one tab for the text editor, one for the dvi file, and so on. And if you're trying to open all windows from the terminal, you can forget it. I'm trying use the terminal as much as possible, and while I have Yakuake, it is still a bother having so many tabs and seeing which of those have an application I've killed and so on.  So, is there a way to open an application/file from the terminal so that the status doesn't show and immediately gives the prompt so that we can use it to open more applications? How can I avoid Java code in JSP files, using JSP 2? Cannot change lock screen background on Ubuntu 18.04 Before you mark the question as a duplicate, I read all of the posts regarding this, but nothing helped me. I'd like to change the background picture of the lock screen.    I changed the ubuntu.css and gdm3.css accordingly to   #lockDialogGroup {   background: #000000 url(file:///usr/share/wallpapers/minimalistic-gray_00323985.jpg);   background-repeat: no-repeat;   background-size: cover;   background-position: center; }   Which results in a change of the Background of the log in screen, not the lock screen. When I press super + L the screen containing time has the correct background. When I swipe it up to tipe in my password, the purple Ubuntu screen still appears. If I click to change the user, the log in screen appears with the right background. I have the same background picture enabled in gnome tweaks for desktop background and lock screen.   I'm running Ubuntu 18.04 GNOME on a TuXedo Laptop. And I use Communitheme - maybe thats the problem?  Any ideas why it doesn't work? (I rebooted multiple times, so that's not the problem.)  EDIT: The output of sudo nano /usr/share/gnome-shell/modes/ubuntu.json is  {     "parentMode": "user",     "stylesheetName": "ubuntu.css",     "enabledExtensions": ["ubuntu-dock@ubuntu.com", "ubuntu-appindicators@ubuntu.com"] } Recover harddrive data Prove: if $a,b\in G$ commute with probability $>5/8$, then $G$ is abelian Suppose that $G$ is a finite group. If $P( ab=ba ) &gt;5/8$, prove $G$ is abelian. When I tried to connect my Ubuntu 13.10 to my VM Centos 6.5 using ssh appear the message "Connection refused" or "No route to host" even than I change the port, noting change.    I need to use SSH, VPN and Samba, but this IP in my VM Centos do not work.  How Can I resolve this problem? Linux ACL behaviour: settings the mask changes 'ls' output, but not actual permissions It might be the time of night, but this is puzzling me. Picture the following.  [root@node1 acltest]# getfacl foo/ # file: foo # owner: root # group: testuser user::rwx group::r-x other::---  [root@node1 acltest]# ls -la . total 24 drwxr-xr-x  3 root root     4096 Feb  9 21:53 . drwxr-xr-x 25 root root     4096 Feb  9 21:54 .. drwxr-x---  2 root testuser 4096 Feb  9 21:53 foo [root@node1 acltest]# setfacl -m m::rwx foo [root@node1 acltest]# getfacl foo/ # file: foo # owner: root # group: testuser user::rwx group::r-x mask::rwx other::---  [root@node1 acltest]# ls -la . total 24 drwxr-xr-x   3 root root     4096 Feb  9 21:53 . drwxr-xr-x  25 root root     4096 Feb  9 21:54 .. drwxrwx---+  2 root testuser 4096 Feb  9 21:53 foo [root@node1 acltest]# su - testuser [testuser@node1 ~]$ cd /acltest/foo/ [testuser@node1 foo]$ ls -la . total 16 drwxrwx---+ 2 root testuser 4096 Feb  9 21:53 . drwxr-xr-x  3 root root     4096 Feb  9 21:53 .. [testuser@node1 foo]$ touch bar touch: cannot touch `bar': Permission denied   In words: I create a directory foo, with mode 0750, root as owner and testuser as the group. (testuser is the private group of testuser, but that doesn't matter.)  The getfacl command correctly shows no ACL's on this directory and there is not mask yet. The mask will be set accordingly to the group permissions if I would add a named group or user now.  If I explicitly set the mask to rwx now, the group permissions as shown by ls change too. I know it happens the other way around (the mask changes when the group permissions change), but this seems puzzling.  The more puzzling because the getfacl output does not show the group permissions as rwx but - as said - ls does.  Which one is right? Apparently, the output of getfacl is right, because testuser cannot write to foo. As expected, by the way, because I did not grant the testuser group any permissions to do so.  It goes on. I cannot allow the testuser group write permissions on foo by just using chmod. I have to explicitly set an ACL using setfacl -m g:testuser:rwx foo to allow testuser to finally touch foo/bar.   Can someone explain the rationale behind the difference in the outputs of getfacl and ls? I know it can be tricky to have normal permissions go together with ACL's, but this seems plain wrong. (Though I expect to be missing something glaringly obvious ;))  I have already seen How to get straight quotation marks? How do I get straight quotation marks, i.e., " and ' in TeX?  (No, \verb changes the font and this is unacceptable.)  [Edit]  I forgot to mention that I’m using XeLaTeX, and fontspec is a necessity.  The first two proposed answers did work, without fontspec. From SL Loney Trigonometry:     Prove that   $$r^2+r_1^2+r_2^2+r_3^2=16R^2-a^2-b^2-c^2$$   for a triangle with sides $a$, $b$, $c$, circumradius $R$, inradius $r$, and exradii $r_1$, $r_2$, $r_3$.   This one is a really dirty question.   I have tried a lot of stuff like $r=4R\times \Pi(\sin\frac{A}{2}$) and  $r_1=4R\times\sin\frac{A}{2}\cos\frac{B}2\cos\frac{C}2$ etc..  There are other ways like $-r+r_1+r_2+r_3=4R$,  but all these are way too cumbersome or clumsy.   Anything more intuitive? Floating point calculations in LaTeX? Definite integral, quotient of logarithm and polynomial: $I(\lambda)=\int_0^{\infty}\frac{\ln ^2x}{x^2+\lambda x+\lambda ^2}\text{d}x$ Why should users never use normal sudo to start graphical applications? Regex to validate date format dd/mm/yyyy Pgfplots: How to fill area under a curve in a 3d plot similar to \closedcycle in 2d How can I fill the area under a curve in a 3d plot, similar to the \closedcycle command in ordinary 2d plots? Applying this command does a filling which is not rotated.  Minimal working example:  \documentclass{article}  \usepackage{tikz} \usepackage{pgfplots} \begin{document}   \begin{tikzpicture}      \begin{axis}[     xmin=0,xmax=3,     zmin=0,zmax=2     ]         \addplot3[red,domain=0:1,fill=blue,opacity=0.5,samples y=0] (2,x,x^2) \closedcycle ;      \end{axis}   \end{tikzpicture} \end{document}   In 2D it looks like this  \documentclass{article} \usepackage{tikz} \usepackage{pgfplots} \begin{document}   \begin{tikzpicture}   \begin{axis}[domain=0:1     ]         \addplot[red,domain=0:1,fill=blue,opacity=0.5,samples y=0] {x^2} \closedcycle ;   \end{axis}   \end{tikzpicture} \end{document}   How can I easily apply this to a 3D plot? Eulerian Paths in a Complete Graph $K_5$ As the title suggests, I’m simply looking for a method to compute the number of Eulerian Paths in the complete graph $K_5$, where all paths start from the same node. Since there are 5 nodes, all Eulerian paths must be Eulerian circuits as well.  Thanks. I just wrote code for this, and I got it a little bit ugly. Can you help me to fix this. And how to change those nands for not, like it is on nand 3,4,5? Please help!  PS. What I mean by these nands for not or whatever this is Adding execute permission in opt folder I am trying to install oracle database in Ubuntu 16.04 LTS. I had unzipped the oracle database file in opt folder,but now when I am trying to give execute right to the sqldeveloper file using chmod +x sqldeveloper.sh, it's throwing this error:  chmod: changing permissions of 'sqldeveloper.sh': Operation not permitted Windows update doesn't progress beyond 0 KB 0% I have Windows&nbsp;7 64-bit and the  isn't working properly. What can I do? The product of $n$ consecutive integers is divisible by $n$ factorial