How to collect command's output/results to the log file? What command can write all msg's in shell to the file?
How do I save the output of a command to a file?  Is there a way without using any software? I would like to know how.
Draw power from a portable mobile charger to power circuits I usually power my beginner prototype circuits using mb102 power supply board, but it needs an external elimeter to draw power and then regulate it.  I was looking for a portable solution for my 5 volt and 3.3 volt circuit needs and came up with using a portable battery charger for mobile phones.  I tried powering up a simple transistor and LED circuit with it but it wouldn't power-up.   I feel that there is some load sensing circuit in the portable charger which doesn't detect these low power circuits.  I also tried connecting different resistors to the charger, the charger outputs 5 Volts for a few seconds and then again shuts down and doesn't stay ON continuously.  It would be really comfortable to use a portable charger since it could be charged using a phone charger and would be very handy.  What can I do to make the charger output power on low loads? Why can't I find any manpages? I'm working on a Power8 server running Ubuntu 16.04.2 LTS:  $ uname -a     Linux power 4.4.0-75-generic #96-Ubuntu SMP Thu Apr 20 09:55:30 UTC 2017 ppc64le ppc64le ppc64le GNU/Linux  $ cat /etc/lsb-release DISTRIB_ID=Ubuntu DISTRIB_RELEASE=16.04 DISTRIB_CODENAME=xenial DISTRIB_DESCRIPTION="Ubuntu 16.04.2 LTS"   None of the usual manpages appear to be installed. Even a simple command like:  man man   returns   No manual entry for man See 'man 7 undocumented' for help when manual pages are not available.   This goes for a variety of other tools, like ls, grep, etc. and library functions like usleep, printf, and so on.  I've checked that at least some manpages are actually installed:  $ dpkg -l | grep -i manpages ii  manpages                           4.04-2                                     all          Manual pages about using a GNU/Linux system ii  manpages-dev                       4.04-2                                     all          Manual pages about using GNU/Linux for development ii  manpages-posix                     2013a-1                                    all          Manual pages about using POSIX system ii  manpages-posix-dev                 2013a-1                                    all          Manual pages about using a POSIX system for development   Am I missing something? Is this specific to the ppc64le architecture? Or is there something else I can/should install to access these manpages?  Update: As requested, I ran sudo mandb. The result was:  0 man subdirectories contained newer manual pages. 0 manual pages were added. 0 stray cats were added. 2 old database entries were purged.   There were no changes to man man and other such commands.  Additionally, the output of manpath was:  $ manpath -g /usr/man:/usr/share/man:/usr/local/man:/usr/local/share/man:/usr/X11R6/man:/opt/man $ manpath -c /var/cache/man/oldlocal:/var/cache/man/local:/var/cache/man Differences between astronomy, astrophysics and cosmology? Function return object Avoiding if statement inside a for loop? Does Mathematica have a "MATLAB Builder" equivalent? How do I find this limit: $\lim_{n\to\infty} \left[ n-{n\over e}\left(1+{1\over n}\right)^n \right]$? How do I declare and initialize an array in Java? Is there any way to deserialize JSON into an object using JSON.deserialize if some of the property names in the JSON are reserved words in apex? I want to do something like this:  string jsonString = '{"currency" : "ABC"}'; public class JSONResult {     public string currency; } JSONResult res = (JSONResult) JSON.deserialize(jsonString, JSONResult.class); system.debug(res);   but of course I get an error that the identifier name is reserved. A isometric map in metric space is surjective? How do I match any character across multiple lines in a regular expression? If the universe is 3D, how is space-time like a "fabric"? Disallow downvoting other answers if I've posted my own Possible Duplicates:        As Dan Dyer mentioned in his comment on , there is a conflict of interest when you have posted your own answer and are allowed to downvote other answers.  Despite the vote editing window being drastically reduced, the fundamental problem remains: I can downvote the other answers permanently and still benefit - my answer gets upvoted ONCE and wham, I have just made up the rep loss for my 10 other downvotes. The vote editing window fixes part of the problem, but there is a more complete fix that has the extra benefit of not preventing legitimate vote changes: to disallow downvotes on competing answers when you have posted one yourself.  The temptation to wrongfully downvote competing answers is huge. The rep loss is tiny in comparison. It has to be in order for people to continue to legitimately downvote.  Details:   If I have previously voted and then post my own answers, delete my downvotes. Continue to allow me to remove the upvotes - I think this is fully legitimate. If I delete my answer it's probably best to continue to deny downvotes (perhaps even including the question), but I don't have a strong opinion either way. Is there any API function for shutting down Windows while installing any pending updates? Ruby can add methods to the Number class and other core types to get effects like this:  1.should_equal(1)   But it seems like Python cannot do this. Is this true? And if so, why? Does it have something to do with the fact that type can't be modified?  Update: Rather than talking about different definitions of monkey patching, I would like to just focus on the example above. I have already concluded that it cannot be done as a few of you have answered. But I would like a more detailed explanation of why it cannot be done, and maybe what feature, if available in Python, would allow this.  To answer some of you: The reason I might want to do this is simply aesthetics/readability.    item.price.should_equal(19.99)   This reads more like English and clearly indicates which is the tested value and which is the expected value, as supposed to:  should_equal(item.price, 19.99)   This concept is what  and some other Ruby frameworks are based on. migrating / merging iphone contacts I have an iPhone 6 (with proper iTunes backup) where all of my contacts where, but I bought a new iPhone 7 and had to initialize it as new iPhone, due to several time-related constraints, so now I have a few but new contacts on my new phone, but none of the older ones, but would be the best practice oriented, for just recovering the old contacts from the iTunes backups?  PS: I still have the old iPhone 6, so it could be used as "temporary storage" if needed. I recently renewed my passport. I also have an expired passport which has my Canada visa (visitor's) valid for another three years. I have already used my Canadian visa which is multiple entry. I am planning to visit Canada this summer.  Since my valid Canadian visa is in my old/expired passport, do I need to renew/transfer my Canada visa or can I simply travel with valid visa in old passport? I recall in at least two episodes of Star Trek ( from the original series and  from The Next Generation) that there is reference to and contact with species from external galaxies.  By the 29th century, we see that timeships exist.  My question is, is there any reference to intergalactic relations in Star Trek in the future (say, by the 29th Century), or does the Star Trek Universe stay in the Milky Way Galaxy? If $\alpha$ is a real root of the equation   $$x^5-x^3+x-2=0$$   find the value of $\lfloor {\alpha}^6 \rfloor$.      This one totally stumped me. We are asked to calculate $\lfloor {\alpha}^6 \rfloor$ without actually calculating the root or using wolfram alpha or any other calculator. I found that the above equation has only one real root by sketching its graph using calculus. I was also able to use the intermediate value theorem to conclude that $1&lt;\alpha&lt;2$ , but this is of little use while calculating $\lfloor {\alpha}^6 \rfloor$. Please help! I was reading a  where the author mentions: "The coefficient of variation is primarily a descriptive statistic, but it is amenable to statistical inferences such as null hypothesis testing or confidence intervals. Standard procedures are often very dependent of the normality assumption and current work is exploring alternative procedures which are less dependent on this normality assumption."  The paper is from 2010. So my question is: has there been any recent "advancements" in terms of a coefficient of variation statistic that is not dependent upon the normality assumption? And, is this what one may call a non-parametric CV?