What is first line written in shell script What is the meaning of that If I didn’t write that line what will happen Then how to run the script
So, I thought I had a good understanding of this, but just ran a test (in response to a conversation where I disagreed with someone) and found that my understanding is flawed...  In as much detail as possible what exactly happens when I execute a file in my shell? What I mean is, if I type: ./somefile some arguments into my shell and press return (and somefile exists in the cwd, and I have read+execute permissions on somefile) then what happens under the hood?  I thought the answer was:   The shell make a syscall to exec, passing the path to somefile The kernel examines somefile and looks at  of the file to determine if it is a format the processor can handle If the magic number indicates that the file is in a format the processor can execute, then   a new process is created (with an entry in the process table) somefile is read/mapped to memory. A stack is created and execution jumps to the entry point of the code of somefile, with ARGV initialized to an array of the parameters (a char**, ["some","arguments"])  If the magic number is a  then exec() spawns a new process as above, but the executable used is the interpreter referenced by the shebang (e.g. /bin/bash or /bin/perl) and somefile is passed to STDIN If the file doesn't have a valid magic number, then an error like "invalid file (bad magic number): Exec format error" occurs   However someone told me that if the file is plain text, then the shell tries to execute the commands (as if I had typed bash somefile). I didn't believe this, but I just tried it, and it was correct. So I clearly have some misconceptions about what actually happens here, and would like to understand the mechanics.  What exactly happens when I execute a file in my shell? (in as much detail is reasonable...)
How do you make the shapefile a Read-only so the client can not make any edits using 10.2.2 ArcGIS.  It is not within a geodatabase, just a stand alone shapefile.  I am using Windows 8 Proving an inequality by induction, how to figure out intermediate inductive steps? I'm working on proving the following statement using induction:  $$ \sum_{r=1}^n \frac{1}{r^2} \le \frac{2n}{n+1} $$  Fair enough. I'll start with the basis step:  Basis Step: (n=1) $$ \sum_{r=1}^n \frac{1}{r^2} \le \frac{2n}{n+1} $$ $$ \frac{1}{1^2} \le \frac{2}{1+1} $$ $$ 1 \le 1  \checkmark  $$  Inductive Step: $$ \sum_{r=1}^{n+1} \frac{1}{r^2} \le \frac{2(n+1)}{(n+1)+1} $$ $$ \sum_{r=1}^{n+1} \frac{1}{r^2} \le \frac{2(n+1)}{n+2} $$  My goal is to prove $\forall_{n\ge1} s(n) \implies s(n+1) $ or that this inequality holds true for all $n\ge1$.  I'm not quite sure to go from here on the inductive step. I understand that I need to basically work some clever substitution and manipulation into the problem to end up with: $$ \sum_{r=1}^{n+1} \frac{1}{r^2} \le \frac{2n}{n+1} $$  However, I'm not quite sure what needs to done to obtain this after attempting a few times. When a body lies on the surface of the Earth it is under the influence of gravity. The force on the body due to gravity causes it to exert a force on the ground and the normal reaction acts in the opposite direction causing the resultant force on the body to be zero.  However, how can the body exert a force on the ground when it does not have any acceleration? Since force equals mass times acceleration how does a body without acceleration experience a force? How can I split an equation over two (or more) lines I am having the following equation:  \begin{equation}   Q(\lambda,\hat{\lambda}) = -\frac{1}{2} P(O \mid \lambda ) \sum_s \sum_m \sum_t \gamma_m^{(s)} (t) \left( n \log(2 \pi ) + \log \left| C_m^{(s)} \right| + \left( \mathbf{o}_t - \hat{\mu}_m^{(s)} \right) ^T C_m^{(s)-1} \left(\mathbf{o}_t - \hat{\mu}_m^{(s)}\right) \right) \end{equation}   which does not very well fit on one line. How can I split this over two lines? What I have in mind is that I specify the splitting place, and that the first line is left aligned and the second line right aligned to make clear that it is still the same equation.  The linebreak \\ does not work. number of distinct solution of Integral equation Total number of distinct $0\leq x\leq 1$ for which $\displaystyle \int_{0}^{x}\frac{t^2}{1+t^4}dt = 2x-1$   $\bf{My\; Try::}$ Given $\displaystyle \underbrace{\int_{0}^{x}\frac{t^2}{1+t^4}dt}_{\geq 0} = 2x-1\;,$ Where $0\leq x\leq 1$  So we get $\displaystyle x\geq \frac{1}{2}\;\;\;,$ Now  $\displaystyle \frac{d}{dx}\left\{\int_{0}^{x}\frac{t^2}{1+t^4}dt\right\} =\frac{d}{dx}(2x-1)$  So $$\frac{x^2}{1+x^4}=2\Rightarrow \underbrace{x^2+\frac{1}{x^2}}_{\geq 2} = \frac{1}{2}$$  So no real values of $x$  Is my solution is Right, If not then how can i solve it some short way, Thanks Because of past conflicts, I don't believe my advisor will write me a good LOR for postdoc positions. What should I do? Confusing article status for journals of American Mathematical Society: "reviewing" AND "being handled by an editor" The web page of my article in the AMS editorial system for some three months says &quot;Article status: Reviewing&quot; and in the next line &quot;Your paper is being handled by an editor&quot;. I find this confusing as the &quot;reviewing&quot; status appears to suggest that the article is with the referee(s) rather than with the editor but this in turn seems to contradict the line &quot;Your paper is being handled by an editor&quot;.  Could someone with enough experience with AMS journals please explain how should one interpret the combination of &quot;Article status: Reviewing&quot; and the line &quot;Your paper is being handled by an editor&quot; at the article page? More broadly, which are the possible article statuses in the AMS editorial system?  Many thanks in advance. If I leave fully-cooked food (particularly meat) out at warm temperature - say on the counter or in a crock pot that's been turned off -  how long will it stay safe to eat?  Does it make any difference if I re-cook the food afterward? Were I rich, I would live on Long Island.   If I were rich, I would live on Long Island.   Is the first sentence still used, or is used in particular contexts (in example, to give emphasis to the sentence)? The FAQ says that Community Wiki works:     by transferring ownership of the post   from the original author to the   community. They make the post easier   to edit and maintain by a wider group   of users, but they do not contribute   to any user's reputation.   But using the new edit suggestion system, everyone can edit. It's no longer true that community wiki makes a post easier to edit.  Does community wiki still serve a function?    What are good examples of community wiki mode doing what it's supposed to do? Is there a way to determine what version (distribution &amp; kernel version, I suppose) of Linux is running (from the command-line), that works on any Linux system? Would a very small creature inside a sealed container carried by a character take damage from AOE spells? Assume character A is in the AOE of a damaging spell.  Character A is carrying a closed container inside his backpack, alongside several sheets of parchment.  Damaging spell description specifically states that items carried by a creature are not damaged even on a failed save. Unattended objects are damaged, though.  Inside said container there is a small creature. Creature has no problem living inside container for a long amount of time.  Does this creature take damage from the spell? If it does not, what mechanic prevents damage? Find a function $f: \mathbb{R} \to \mathbb{R}$ that is continuous at precisely one point? Is the function $f(x) = \lim_{k \to +\infty} \tan{kx}$ a right example?  But I do not know whether this is a function at first. Is this a function?  Could you give a correct real-valued function that is continuous at precisely one point?  Thanks. I am travelling form Delhi (DEL) to San Francisco (SFO), I have to make a connection flight in Vienna that would take me to Frankfurt (FRA). My flight to SFO is from FRA, I have one ticket for entire journey and the flights are operated by Lufthansa or its subsidiaries.  Do I need a transit visa? My flight arrives at Vienna international airport and leaves from the same, and for second leg it arrives at Frankfurt international airport.  I asked this question as an addendum to my  but was advised to make a new post.  I hold Indian passport and valid US visa. Let $\kappa, \lambda,\theta$ be infinite cardinals of $M$ where $M$ is a transitive model of ZFC. Let $\mathcal{P}=Fn(\kappa\times \omega,2)$ (finite functions from $\kappa\times \omega$ to 2) and G is a (M,P)-generic set. I want to show $(\lambda^\theta)^{M[G]}=(max(\kappa,\lambda)^\theta)^M$. One direction is easy $(\lambda^\theta)^M \leq (\lambda^\theta)^{M[G]}$ and $(\kappa^\theta)^M\leq (\kappa^\theta)^{M[G]}\leq ((2^\omega)^\theta)^{M[G]}=(2^\theta)^{M[G]}\leq (\lambda^\theta)^{M[G]}$ where $(\kappa \leq 2^\omega)^{M[G]}$ is by the forcing construction. But now I am not quite sure how to get the other direction. Any thoughts? When looking at a PDF document I often want to zoom-out to scroll quickly to its contents and get an overview.  However, when I zoom-out past a certain threshold (it seems to differ per PDF) Safari thinks I want to see the tab overview:    I have never found a use for this function, so it only causes annoyance.  Can I turn this tab overview off somehow? A solution that uncouples the pinch-to-zoom gesture from the functionality would also work.  I'm on Mountain Lion 10.8.5 with Safari 6.1.3. Why does a find field value in one application show up in a the find field of another application? On my MacBook Pro I have found that several applications seem to share the value for a find.  For example, I searched 'applestackexchange' in Safari's unified address bar, then I switch to Xcode and click into a Find field.  The first word of my search in Safari then appears there.  iTerm2 and Sublime Text 2 also seem to participate in this sharing.  Running latest Mountain Lion on  a 2012 MBP. Residues of $z^2\sin(\frac{1}{z})$ No Time in Top Panel (Gnome Classic) I've been using Ubuntu with Gnome Classic for a while and I've noticed recently that in the "Indicator Applet Complete" in the Top Panel, my name and the clock have disappeared.    I think it happened a while ago when I was messing around with packages. Every time I did apt-get... it would say "the following packages can be removed by apt-get autoremove", so I did it and then the clock and my name stopped appearing.   Can anyone help me? Thanks. It would be greatly appreciated. How exactly do I install Minecraft Mods and what is Forge? I'm having a really, really hard time figuring out how to install mods on Minecraft. I've looked everywhere I can think of for help but the information is almost always outdated or unhelpful.  I've seen on several sites about the use of something called Forge. The Mod I want to use requires 1.6.4 Forge and I have both Forge and the Mod folders sitting in my downloads folder.  I haven't installed any kind of mods for any game prior to this and I have little clue to the technical side of Minecraft, so please keep this in mind when you give me an answer please!  Things that might help you figure out how to help me:   I want to play this mod  and am using the 1.6.4 Forge given on a link that website gives