I have an old lubuntu system (4.13.0 update (see comments) 17.10), and I can hardly update any software, nor install new, because most repos are not there anymore. I simply want to upgrade, version by version, walk the long way to some modern version. When I try this:  sudo apt-get dist-upgrade   I get the answer  The following packages will be upgraded:   snapd waterfox   This is certainly not what I expect. I assume that I have made some mistakes, but I am clueless.  Is there any way to upgrade the system from this state of affairs?   I know that questions about old systems are not wanted here, but I hope this is treated as an obvious exception. If not, please tell men where I can get help other than here. Thanks!  update because asked to clarify why this question is not a duplicate: I do not want to install old versions of software on an old system. I simply want to upgrade the system. In the comments, I got a helpful answer (link to another question) of how to start the process. The information given below is, to my understanding, certainly helpful for others with similar questions.
Recently I have installed an older version of Ubuntu on my old machine. Whenever I try to install any software, I get an error saying it couldn't be found:  $ sudo apt-get install vlc Reading package lists... Done                Building dependency tree        Reading state information... Done     E: Couldn't find package vlc
Add new alias to Gmail without SMTP (forwarding-only address) We are using following code in .php script for generate .pdf file.  $result1 = exec("R CMD Sweave /var/www/html/r/r_latex_sweave.Rnw");  $result2 = exec("pdflatex /var/www/html/r/r_latex_sweave.tex");   but, we are getting this errors when we are executing .Rnw and .tex files.  ! I can't write on file `r_latex_sweave.log'. Please type another transcript file name:  ! Emergency stop !  ==> Fatal error occurred, no output PDF file produced!  Note: We have .tex and .Rnw folder in /var/www/html folder? Which is the correct question ("Who has" vs "Who have")? The situation is that:  We've already read three English novels.  Which is the correct question for that situation?   Who has already read three English novels?  Who have already read three English novels?    Or could both be correct? Please also provide the grammatical reasons for your answers. I'm pretty new to this and this is my first question here, any help would be greatly appreciated.  So basically what I want to achieve is a floor material as seen in this photo...    ...the reflections are very crisp but dim.  With a glossy shader I get the following results:    First picture: reflections are blurry  Second picture: roughness of the material looks right but reflection is bright red  Third picture: If tinted in any other color than white, it seems to produce the result I want. Reflection is sharp and gets tinted blue. What I need is the reflection to be tinted white.  Thanks for any help. I love recursion. I think it simplifies things a lot. Another may disagree; I think it also makes the code a lot easier to read. However, I've noticed that recursion is not used as much in languages such C# as they are in LISP (which by the way is my favorite language because of the recursion).   Does anybody know if there is any good reasons not use recursion in the languages such as C#? Is it more expensive than iteration? Let $a_1=1$ and $a_n=n(a_{n-1}+1)$ for $n=2,3,\dots$. Define $$P_n=\left(1+\frac{1}{a_1}\right)\left(1+\frac{1}{a_2}\right)\dots\left(1+\frac{1}{a_n}\right)$$Find $$\lim_{n \to \infty}P_n$$   Trial: $$1+\frac{1}{a_n}=1+\frac{1}{n(a_{n-1}+1)}\;.$$ But I can't simplyfy.Please help. How can I get octal file permissions from command line? Add the Same Modifier to Multiple Objects at Once? From :     "[...] the stress vector $T$ across a surface will always be a linear function of the surface's normal vector $n$, the unit-length vector that is perpendicular to it. [...] The linear relation between $T$ and $n$ follows from the fundamental laws of conservation of linear momentum and static equilibrium of forces, and is therefore mathematically exact, for any material and any stress situation. The components of the Cauchy stress tensor at every point in a material satisfy the equilibrium equations (Cauchy’s equations of motion for zero acceleration). Moreover, the principle of conservation of angular momentum implies that the stress tensor is symmetric."   What is the more detailed explanation for this, and/or where can I find it? Error on \usepackage {geometry} text property Why do I keep getting told I posted less than 15 characters when I posted more than 15? I tried to post the following comment and it claims it was less than 15 when it was more.  Based on Tim's comment and testing I believe it would not let me post because with @Shadow removed it is less than 15. However, the characters left message indicates I have passed the 15 character minimum thus it is wrong.  This is the bug I'm reporting:  The characters remaining message and the characters left message do not take into account striping out @name prefixes. Is this a correct way for passing an environment variable in sudo ?  sudo -u www-data -b env FOOBAR="foobar" /home/user/folder/daemon How can I get bash to perform tab-completion for my aliases? I have a bunch of bash completion scripts set up (mostly using bash-it and some manually setup).    I also have a bunch of aliases setup for common tasks like gco for git checkout. Right now I can type git checkout dTab and develop is completed for me but when I type gco dTab it does not complete.    I'm assuming this is because the completion script is completing on git and it fails to see gco.    Is there a way to generically/programmatically get all of my completion scripts to work with my aliases?  Not being able to complete when using the alias kind of defeats the purpose of the alias. WIFI connection not working I ran these commands:  sudo rmmod iwlwif sudo modprobe iwlwifi 11n_disable=1 sudo su echo "options iwlwifi 11n_disable=1" &gt;&gt; /etc/modprobe.d/iwlwifi.conf   Now, my WiFi connection is lost and there is no WiFi option in the network manager. How can I restore it? Guid vs INT - Which is better as a primary key? When I use the mobile app to vote for an answer that was awarded a bounty,  the bounty is no longer shown until I reload the answers. Ideal charging / discharging percentage for maximum battery life? One of my friends has a relatively new Samsung smartphone. He has this app that notifies him whenever the charging is up to 80%, and tells him to unplug the charger.  He tells me that it will increase the number of charging cycles for his battery. He says that if he lets it charge all the way up to 100%, it will mean he has to replace the battery of the phone more often.  Is this true?  Somehow, I feel this is a thing of the past. I thought the internal architecture of batteries these days was made so that it wouldn't drop too low or too high. (In other words, when the phone is at 100%, it isn't really 100%. It's what the battery can safely be charged to in order not to degenerate too much.)  Here's a  which taught me something about this. I have a paradox table from a legacy system I need to run a single query on.  The field names have spaces in them - i.e. "Street 1".  When I try and formulate a query in delphi for only the "Street 1" field, I get an error - Invalid use of keyword. Token: 1, Line Number: 1  Delphi V7 - object pascal, standard Tquery object name query1. Why should I avoid multiple inheritance in C++? Is it a good concept to use multiple inheritance or can I do other things instead? converting date string to date format