I have a very old laptop Toshiba Satellite M305-S4848, from 2010. I used to run Ubuntu 14.04 on it until a few years ago. Now, I’m trying to use it again. Everything is fine, except for the fact it can’t update its Ubuntu 14.04 (nor the Firefox). It tells me to check the internet connection, but everything else is fine. I’m even typing this from it right now. Please, how should I proceed to solve this? Thanks in advance.
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
Performance differences between pipelines and process substitution I tend to use pipelines in my bash scripts over process substitution in most situations, especially in cases of using multiple sets of commands as it seems more readable to do ... | ... | ... over ... &lt; &lt;(... &lt; &lt;(...)).  I'm wondering though why using process substitution is much faster in some situations than using a pipeline.  To test this, I timed two scripts using 10000 iterations of the same attached commands with one using a pipeline and another using process substitution.  Scripts:  pipeline.bash:  for i in {1..10000}; do     echo foo bar |     while read; do         echo $REPLY &gt;/dev/null     done done   proc-sub.bash  for i in {1..10000}; do     while read; do         echo $REPLY &gt;/dev/null     done &lt; &lt;(echo foo bar) done   Results:  ~$ time ./pipeline.bash  real    0m17.678s user    0m14.666s sys     0m14.807s  ~$ time ./proc-sub.bash  real    0m8.479s user    0m4.649s sys     0m6.358s   I know that pipelines create a sub process whereas process substitution creates a named pipe or some file in /dev/fd, but am unclear about how those differences impact performance. can't get placeholder attribute to work in IE using iframe Linux equivalent to PowerShell's "one-to-many" remoting Repeating "to" and "will" in enumerations of verbs Should I use the second "will" in constructions like this one: "it will definitely help you and will make the text more readable"  And should I write "to" before every infinitive in enumeration, or only before the first one, e.g. "it helps to develop and test" or "it helps to develop and to test"? 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Munich  Airport transit privilege does not apply in the following cases and you will need to get a visitor visa if: You are transiting through two or more airports in the Schengen Countries A Riemann integrable function must have infinitely many points of continuity Let $T:V\to V$ be a linear map, where $V$ is an inner product space. Given $T^2=\frac{T+T^*}{2}$, prove that $T$ is normal and that $T=T^2$. Let $T:V\to V$ be a linear map, where $V$ is a finite-dimensional inner product space. Given $T^2=\frac{T+T^{*}}{2}$, I would like to prove that $T$ is normal and that $T=T^2$. The first part, to prove that $T$ is normal, is quite easy: from $T^2=\frac{T+T^{*}}{2}$ we'll have $\,T^{*}=2T^2 - T$, and as $TT^{*} = 2T^3 -T^2 = T^{*}T$. Now, I need to prove that $T=T^*$, then $T = T^2$ is immediate. I have been thinking about this question for some days and I can't figure out in what technique to prove that $T = T^{*}$. So, say you are a wizard 15/warlock 2. You have the Lance of Lethargy invocation, which pushes an enemy you target with eldritch blast and hit back 10 feet. Say you put a demiplane entrance ~5 feet behind the enemy you target with it. When you hit, you throw the enemy in. Before all this, you had put a Glyph of Warding in there on one of the surfaces. What would be the limit to the trigger for this? Would it be forced to be touch or proximity, or could you base it off something like hostility towards the caster?      ... When you cast this spell, you inscribe a glyph that later unleashes a magical effect ... You decide what triggers the glyph when you cast the spell. For glyphs inscribed on a surface, the most typical triggers include touching or standing on the glyph, ... (PHB 245)   The key word here is "typical". Based on Google's definition, the informal definition of "typical" is     showing the characteristics expected of or popularly associated with a particular person, situation, or thing.   This means, if my assumption is true, that the triggers in the PHB are only the most common ones. Other than the one about being forcibly at maximum 10 feet in diameter in the PHB, I cannot see a limit. Though I probably should assume this would all be DM discretion, (and I know that I sound like a broken record here) but could the trigger be hostility toward the caster, or something else, like being a specific race, gender, from a specific place, etc., or would it be forced to being something from the PHB? In Drush 8, my site aliases are loaded correctly from ~/.drush/mysite.aliases.drushrc.php.  E.g.  $aliases['dev'] = array(   'root' =&gt; '/var/www/html/mysite.dev/docroot',   'uri' =&gt; 'mysite.prod.acquia-sites.com',   'remote-host' =&gt; 'mysite.ssh.acquia-sites.com',   'remote-user' =&gt; 'mysite.dev',   'path-aliases' =&gt; array(     '%drush-script' =&gt; 'drush' . $drush_major_version,   ), );   However these aliases aren't loaded in Drush 9.  $ drush site-alias {  }   How I should define site aliases in Drush 9? Is there any migration process? Question is about Ubuntu release process. Are migrations from n to n+1 releases expected?  Assuming we have server with installed Ubuntu 14.04 LTS. Will it be smoothly upgradable to Ubuntu 16.04 LTS via apt-get upgrade ?  Assumptions:   scope is software therefore we assume that given hardware is supported on both releases (upgrading from and to) that's why, always before upgrade you are asked to make backup to be able to revert in case of failure