I'm writing a simple script that prompts the user for information and saves it as a variable to be passed as arguments in another command. One of the variables stores a path which may include a space. Using the read command's -r tag, the path is retrieved as 'raw' input, ignoring the backslash escape character.  For example:  read -p "Enter checksum algorithm number (1, 224, 256, 384, 512, 512224, 412256): " -a shaa read -p "Enter a file path: " -re shapath   The problem is I cannot figure out how to run the command with those arguments without it reading the escape character. Solved per @heemayl  I then need to store the output or return value of the command as another variable.  For example:  foo=$(shasum -a "$shaa" "$shapath")   However, when I echo $foo I do not get the expected output of shasum -a "$shaa" "$shapath", but instead get shasum: /.../checksum.dmg  I was able to get it to work by using eval and piping it into var as shown below:  eval shasum -a $sha $shapath &gt; val   I've read I should avoid eval at all costs and it does not allow me to continue forward with the script.
Or, an introductory guide to robust filename handling and other string passing in shell scripts.  I wrote a shell script which works well most of the time. But it chokes on some inputs (e.g. on some file names).  I encountered a problem such as the following:   I have a file name containing a space hello world, and it was treated as two separate files hello and world. I have an input line with two consecutive spaces and they shrank to one in the input. Leading and trailing whitespace disappears from input lines. Sometimes, when the input contains one of the characters \[*?, they are replaced by some text which is is actually the name of files. There is an apostrophe ' (or a double quote ") in the input and things got weird after that point. There is a backslash in the input (or: I am using Cygwin and some of my file names have Windows-style \ separators).   What is going on and how do I fix it?
I'm trying to install Linux alongside my 64-bit Windows 8 and went into my partition manager to find this structure.    In order to create partitions for my Linux install I need to free up some space. I see that the last partition is an empty recovery partition, as you can see highlighted, it's 100% free.  I was wondering is it okay to just remove this partition seeing as it doesn't appear I'll be losing anything?  Not sure if this helps but this is on a Fujitsu AH532 running Windows 8 64-bit with UEFI. Difference between projection and datum? What's the difference between a projection and a datum? The standard font packages make global changes to the fonts in my document. What if I want to use a particular font for just a portion of my text?   How do I find the right name of the font? How do I select the font? How do I restrict the scope of the font change?     There are separate answers for different flavors of TeX (quick links): Is it possible to install Windows from an external hard drive?  I have Windows XP installed on my laptop, and I want to remove it and install Windows 7.  My Windows 7 installation is in an .iso format on an external USB hard drive.  Is it possible to install it or will I need to put in a DVD before I start installing? Best way to save data in a Java application? Find All Solutions to System of Congruence $$ \begin{cases} x\equiv 2 \pmod{3}\\ x\equiv 1 \pmod{4}\\ x\equiv 3 \pmod{5} \end{cases} $$  $ n_1=3\\ n_2=4\\ n_3=5\\ N=n_1 * n_2 * n_3 =60\\ m_1 = 60/3 = 20\\ m_2 = 60/4 = 15\\ m_3 = 60/5 = 12\\ gcd(20,3)=1=-20*1+3*7\\ gcd(15,4)=1=-15*1+4*4\\ gcd(12,5)=1=12*3-5*7\\ x=-20*2-15*1+12*3\equiv -19 \equiv 41 \pmod{60}\\ $  The above is what I've tried so far. Can someone tell me where I'm going wrong? It's my first time doing this and looking at the explanation and examples for the Chinese Remainder Theorem makes my head want to explode. Should I keep my swap file on an SSD drive? I'm considering getting an SSD drive to run as the primary OS partition.  As I understand, this should provide a substantial improvement in performance.     My question is this: Should I leave the swap file on that drive?     The swap partition will be largely random seeks and so should benefit from the speed.  On the other hand, it will be constantly written to which will wear out the drive faster. Proof of $a^{\phi (n) +1} \equiv a \pmod{\! n} $ Carmichael generalization of Fermat-Euler's theorem. Please anyone tell me when we have to use "has been, have been , had been" and something  started in past and still continuing is it possible to use has been ? We have some new hardware in our office which runs its own customized Linux OS.   How do I go about figuring which distro it's based on? I'm not a physicist; I'm just curious about what would happen.  According to this video "" (at 2:50):     "Somebody decided to leave the detectors on but just not take any data. [...] So if it was also going to a magnetic tape - there was no magnetic tape loaded. [...] And what do you think happed? They got this. They got the diffraction pattern."   So the act of measuring (beeing concious of the data) destroys wave-form pattern?  If so lets consider these cases:   What if I'd throw a dice after the experiment to decide if I should look at the data or to destroy it? (e.g. look at the data if the number on dice is even) What if the information about measurement would need to travel longer period of time than the particle would need to hit the wall?    To above cases: Would it mean that information travelled instantly - faster than light or that "the particle can look into the future"? Derivation of survival copula $$ \begin{align}F(x,y) &amp;= P(X\leq x, Y\leq y) \\  &amp;= C(F(x), F(y)) \end{align}$$ The copula of a bivariate distribution is equal to its CDF, $C(u,v) = F(x,y)$. The density of the data's CDF therefore can be expressed as $$f(x,y) = c(u,v) \times f_X(x) f_Y(y)$$ where $c(u,v)$ is the copula density and $f_X(x)$ is a marginal. If $\hat{C}(u,v)$ is the survival copula for determining $$ \begin{align}\bar{F}(x,y) &amp;= P(X&gt; x, Y &gt; y) \\  &amp;= \hat{C}(1-F(x), 1-F(y)) \end{align}$$ how is the first equation of the ordinary copula, $C(u,v)$, linked to the survival copula as $$\hat{C}(u,v) = u + v - 1 + C(1-u,1-v)$$ are $u$ and $v$ merely vectors containing the (ranked) observations of the uniform marginals? A derivation in integrals and probabilities (rather than $F$s) would be good. Why does $F=ma$? Is there a straightforward reason? Why is force = mass $\times$ acceleration? I have searched in many sites but didn't actually get at it. Simply I want to know that if a mass in space moves (gains velocity thus further accelerates), how can I think, postulate and further believe that force = multiplication  of mass and its acceleration ? Are the rules regarding absolute modifiers too absolute? A common grammar lesson that was taught to me in the US and that I've had to teach abroad in EFL classrooms is that we're not to use adverbs of emphasis with absolute modifiers, just as we're not supposed to use them as comparatives or superlatives.  Classic egregious examples of this mistake include very unique and more perfect, which seem obviously flawed to me. Other instances of further modified absolute modifiers are similarly meaningless or contradictory in nature.  I wonder, though, if the rule that I learned isn't overly broad, and whether it's taught similarly in the UK and elsewhere. I find myself modifying absolute modifiers quite regularly, and in some circumstances I think it's not only logical and correct, but quite meaningful. Phrases like almost exactly or virtually all or practically infinite possess a specific meaning that can't really be replicated using nonabsolutes like very nearly or most or quite long.  In my own speech and writing, I use such phrases exactly as I see fit, so this isn't a request for permission, per se. I'm more curious about whether there's a more appropriate rule regarding absolutes that you rely on (and might be used in a classroom). Is smell a bad way of determining whether meat is still good? I have always relied on my sense of smell to determine whether meat (most often chicken) is bad and I thought it was reliable. However, I have just heard that [1] smell is not always reliable, since some of the toxins produced by bacteria won't cause any smell whatsoever and you won't be able to notice that the meat is off until after you've eaten it.   Is this true? If yes, is this true for all meat or only for some? Is there a more reliable way of determining whether meat is still good.  [1] "Heard that" isn't very reliable; so that's why I'm asking the question here. :) Possible to replay repetitive tasks using Python? How do I run 32-bit programs on a 64-bit Debian/Ubuntu? I have a 64-bit (amd64 a.k.a. x86_64) Debian or Ubuntu installation. I need to run 32-bit (i386/i686) programs occasionally, or to compile programs for a 32-bit system. How can I do this with a minimum of fuss?  Bonus: what if I want to run or test with an older or newer release of the distribution? I tried to install WPS Office on my laptop (ubuntu 16.10 Gnome, 64 bit) with  Gdebi installer but it said   Dependency is not satisfiable: libpng12-0   Then I tried to open this library as follows  sudo apt-get install libpng12-0   But I encountered an error:  Reading package lists... Done Building dependency tree        Reading state information... Done Package libpng12-0 is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source  E: Package 'libpng12-0' has no installation candidate   Can anyone help? Thanks a lot The computed moments of log normal distribution can be found . How to compute them? Why do I have blurred vision and how do I fix it?