Stack Overflow app for iOS and Android
Do Stack Overflow and other Stack Exchange sites have an app I can use?
How to do this manually, not installing any tools? I have a 16GB flash drive. I'm running Ubuntu 14.04. I can't open my flash drive and I can't see it in GParted.  After running tail -f /var/log/syslog . After inserting my flash:  USB disconnect, device number 10 Jul  3 16:39:55 rihanna-VGN-Z56GG-B kernel: [ 3309.712166] usb 2-3: new high-speed USB device number 11 using ehci-pci Jul  3 16:39:55 rihanna-VGN-Z56GG-B kernel: [ 3309.846591] usb 2-3: New USB device found, idVendor=090c, idProduct=1000 Jul  3 16:39:55 rihanna-VGN-Z56GG-B kernel: [ 3309.846601] usb 2-3:   New USB device strings: Mfr=1, Product=2, SerialNumber=3     Jul  3 16:39:55 rihanna-VGN-Z56GG-B kernel: [ 3309.846609] usb 2-3: Product: Silicon-Power     Jul  3 16:39:55 rihanna-VGN-Z56GG-B kernel: [ 3309.846615] usb 2-3: Manufacturer: UFD 2.0     Jul  3 16:39:55 rihanna-VGN-Z56GG-B kernel: [ 3309.846622] usb 2-3: SerialNumber: 1401208423400131     Jul  3 16:39:55 rihanna-VGN-Z56GG-B kernel: [ 3309.847176] usb-storage 2-3:1.0: USB Mass Storage device detected     Jul  3 16:39:55 rihanna-VGN-Z56GG-B kernel: [ 3309.847309] scsi12 : usb-storage 2-3:1.0     Jul  3 16:39:55 rihanna-VGN-Z56GG-B mtp-probe: checking bus 2, device 11: "/sys/devices/pci0000:00/0000:00:1d.7/usb2/2-3"     Jul  3 16:39:55 rihanna-VGN-Z56GG-B mtp-probe: bus: 2, device: 11 was not an MTP device     Jul  3 16:40:17 rihanna-VGN-Z56GG-B kernel: [ 3332.176107] usb 2-3: reset high-speed USB device number 11 using ehci-pci     Jul  3 16:40:33 rihanna-VGN-Z56GG-B kernel: [ 3347.288080] usb 2-3: device descriptor read/64, error -110     Jul  3 16:40:48 rihanna-VGN-Z56GG-B kernel: [ 3362.504081] usb 2-3: device descriptor read/64, error -110     Jul  3 16:40:48 rihanna-VGN-Z56GG-B kernel: [ 3362.720076] usb 2-3: reset high-speed USB device number 11 using ehci-pci     Jul  3 16:40:52 rihanna-VGN-Z56GG-B kernel: [ 3366.812110] usb 2-3: reset high-speed USB device number 11 using ehci-pci     Jul  3 16:41:07 rihanna-VGN-Z56GG-B kernel: [ 3381.924082] usb 2-3: device descriptor read/64, error -110     Jul  3 16:41:23 rihanna-VGN-Z56GG-B kernel: [ 3397.356093] usb 2-3: reset high-speed USB device number 11 using ehci-pci     Jul  3 16:41:38 rihanna-VGN-Z56GG-B kernel: [ 3412.468057] usb 2-3: device descriptor read/64, error -110     Jul  3 16:41:54 rihanna-VGN-Z56GG-B kernel: [ 3428.664065] usb 2-3: reset high-speed USB device number 11 using ehci-pci     Jul  3 16:42:09 rihanna-VGN-Z56GG-B kernel: [ 3443.776100] usb 2-3: device descriptor read/64, error -110     Jul  3 16:42:24 rihanna-VGN-Z56GG-B kernel: [ 3458.992085] usb 2-3: device descriptor read/64, error -110     Jul  3 16:42:25 rihanna-VGN-Z56GG-B kernel: [ 3459.208063] usb 2-3: reset high-speed USB device number 11 using ehci-pci     Jul  3 16:42:40 rihanna-VGN-Z56GG-B kernel: [ 3474.320039] usb 2-3: device descriptor read/64, error -110     Jul  3 16:42:50 rihanna-VGN-Z56GG-B kernel: [ 3484.516109] usb 2-3: reset high-speed USB device number 11 using ehci-pci     Jul  3 16:42:50 rihanna-VGN-Z56GG-B kernel: [ 3484.768108] usb 2-3: reset high-speed USB device number 11 using ehci-pci Jul  3 16:43:05 rihanna-VGN-Z56GG-B kernel: [ 3499.880081] usb 2-3: device descriptor read/64, error -110 Jul  3 16:43:20 rihanna-VGN-Z56GG-B kernel: [ 3515.096081] usb 2-3: device descriptor read/64, error -110 Jul  3 16:43:21 rihanna-VGN-Z56GG-B kernel: [ 3515.312048] usb 2-3: reset high-speed USB device number 11 using ehci-pci Jul  3 16:43:36 rihanna-VGN-Z56GG-B kernel: [ 3530.424032] usb 2-3: device descriptor read/64, error -110 Jul  3 16:43:46 rihanna-VGN-Z56GG-B kernel: [ 3540.505230] scsi 12:0:0:0: Device offlined - not ready after error recovery I've bought a  to use with my EOS 200D and while I love the wide aperture, it appears to be quite difficult to achieve sharp focus on people's faces when shooting at f/1.8. I've tried both using Dual Pixel focus in Live View and using the center focusing point in the viewfinder, but it doesn't get me perfect results.  Is this simply a characteristic of cheap wide-aperture lenses? Or is it impossible to get sharp focus with a fully open aperture?  When I'm at at home using a tripod and focusing on a still subject I do get good focus (so it's not a camera or lens issue). But it's hard to do with people who are slightly moving between shots. Punctuation of direct speech, edge cases I recently learned that I have developed a consistent, but entirely wrong approach to punctuating direct speech in fiction. I am in the unenviable position of trying to relearn.  Previously I wrote such things as:     "I'm done." She said.   when the quoted speech was definitely, absolutely the end of a sentence. So now I know I need.     "I'm done," she said.   This follows the rule that a period is only allowed when the end of the spoken sentence is also the end of the sentence in the narrative. For example:     "I'm done." She slammed the door on the way out.   So, it now looks odd to me when there are multiple sentences in the speech:     "I can't take her. I'm done," she said.   Can you reassure me that is correct, or give the correct form? Please don't suggest rewriting the sentence to put 'she said' in the middle - I'm aware of that: I'm specifically asking about the punctuation rules.  The other odd case is speech ending with an ellipsis. Do sentence terminating ellipses (four periods normally) become:     "I can't take her. You know, ...," she said, nodding towards Jane.   If so, are non-terminating ellipses dealt with the same way?     "I can't take ...," she nodded towards Jane, "any more!"   or can non-terminating ellipses be used unadorned?     "I can't take ..." she nodded towards Jane, "any more!"   I'd be very grateful if you could point me at references as well as answers. For the record I am a British writer writing for both British and US publication, so any variation is also interesting to me! How do I reset my Unity configuration? I've been messing around with Unity and broke something, how do I "start over"? I have the following code that will remove lines with the pattern banana and 2 lines after it:  sed '/banana/I,+2 d' file   So far, so good! But I need it to remove 2 lines before banana, but I can't get it with a “minus sign” or whatever (similar to what grep -v -B2 banana file should do but doesn't):  teresaejunior@localhost ~ &gt; LC_ALL=C sed '-2,/banana/I d' file sed: invalid option -- '2' teresaejunior@localhost ~ &gt; LC_ALL=C sed '/banana/I,-2 d' file sed: -e expression #1, char 16: unexpected `,' teresaejunior@localhost ~ &gt; LC_ALL=C sed '/banana/I,2- d' file sed: -e expression #1, char 17: unknown command: `-' Deduction of $\forall y \exists x (x=y)$ Give a deduction of $\forall y \exists x (x=y)$  My thinking is I can prove $\exists x(x=y)$ then use generalization theorem， which is equivalent to prove $\neg \forall x \neg (x=y)$ but I got stuck proving this... thanks in advance  Sorry that I did not specify what deduction system that I want to use here, it is the deduction sequence  where ai is either Axiom or original hypothesis or obtained from MP Asymptotic expansion for Fresnel Integrals If you take the fresnel integrals to be $$S(x) = \int_{0}^{x}\sin \left(\frac { \pi \cdot  t^2}{2} \right) dt$$ How do you find the asymptotic expansion? I know it begins with a $1/2$ but how? Mount cifs Network Drive: write permissions and chown I have access to a cifs network drive. When I mount it under my OSX machine, I can read and write from and to it.   When I mount the drive in ubuntu, using:  sudo mount -t cifs -o username=${USER},password=${PASSWORD} //server-address/folder /mount/path/on/ubuntu   I am not able to write to the network drive, but I can read from it. I have checked the permissions and owner of the mount folder, they look like:  4.0K drwxr-xr-x  4 root root    0 Nov 12  2010 Mounted_folder   I cannot change the owner, because I get the error:  chown: changing ownership of `/Volumes/Mounted_folder': Not a directory   When I descend deeper into the network drive, and change the ownership there, I get the error that I have no permission to change the folder´s owner.  What should I do to activate my write permission? What are these dark spots in my pictures? I've been seeing these dark spots in my pictures. They appear a lot more on some pictures than others, but they are in the same place in the image and independent of the lens being used. Is this dust? I've also heard that you can get oil spots on the sensor.  The image is from a Nikon D7000. What are some examples of induction where the base case is difficult but the inductive step is trivial? According to :     ...proofs by mathematical induction   have two parts: the "base case" that   shows that the theorem is true for a   particular initial value such as n = 0   or n = 1 and then an inductive step   that shows that if the theorem is true   for a certain value of n, it is also   true for the value n + 1. The base   case is often trivial and is   identified as such, although there are   cases where the base case is difficult   but the inductive step is trivial.   What are some examples of proofs by induction where the base case is difficult but the inductive step is trivial? Yes,  but there must be a canonical or most efficient or most concise way. I'll add answers I know of and see what percolates to the top.  To be clear, the question is how best to read the contents of a file into a string. One solution per answer. How to mount a RAM disk on startup? I'm trying to mount a RAM disk on startup with this:  /Users/Aram/Development/Tools/ramdisk.sh  diskutil erasevolume HFS+ "RamDisk" `hdiutil attach -nomount ram://800000`   com.aram.ramdisk.plist  &lt;?xml version="1.0" encoding="UTF-8"?&gt; &lt;!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN"          "http://www.apple.com/DTDs/PropertyList-1.0.dtd"&gt; &lt;plist version="1.0"&gt;     &lt;dict&gt;         &lt;key&gt;Label&lt;/key&gt;         &lt;string&gt;com.aram.ramdisk&lt;/string&gt;         &lt;key&gt;ProgramArguments&lt;/key&gt;         &lt;array&gt;             &lt;string&gt;/bin/sh&lt;/string&gt;             &lt;string&gt;/Users/Aram/Development/Tools/ramdisk.sh&lt;/string&gt;         &lt;/array&gt;         &lt;key&gt;RunAtLoad&lt;/key&gt;         &lt;true/&gt;     &lt;/dict&gt; &lt;/plist&gt;   And then running:   sudo chown root:wheel /Library/LaunchDaemons/com.aram.ramdisk.plist sudo launchctl load -w /Library/LaunchDaemons/com.aram.ramdisk.plist   But I get these in the console:  1/08/12 1:29:25.982 PM fseventsd[64]: could not open &lt;&lt;/Volumes/RamDisk/.fseventsd/fseventsd-uuid&gt;&gt; (No such file or directory) 1/08/12 1:29:25.982 PM fseventsd[64]: log dir: /Volumes/RamDisk/.fseventsd getting new uuid: 102D7293-F1F1-4640-AA50-D547C365339F  1/08/12 1:29:24.561 PM sudo[1193]:     Aram : TTY=ttys000 ; PWD=/Library/LaunchDaemons ; USER=root ; COMMAND=/bin/launchctl load -w /Library/LaunchDaemons/com.aram.ramdisk.plist  1/08/12 1:40:17.052 PM com.apple.launchd[1]: (com.aram.ramdisk) Throttling respawn: Will start in 8 seconds   It works if I set KeepAlive to true, but then it creates a RAM disk every 10 seconds.  Is there a way to delay the script for 10 seconds before running? Can I have multiple DHCP servers on one network? This is a  about Redundant DHCP Servers.   Is it possible to have more than one DHCP server on the same LAN? What are the implications of doing this?    What happens if there is more than one DHCP server available? How do my clients know which one to use?  How can I have DHCP servers supplying addresses to more than one subnet\network segment? How can I configure multiple DHCP servers to supply addresses for the same subnet. Does the OS X log notifications from the Notification Center? Rails Previous Sunday in Relation to Any DateTime Unable to solve equation for a variable by any method Q&A Identification of seldom man-made physical objects not being piece of art? Is SE Q&amp;A format relevant for "identification of seldom physical objects observed in real world"?  Questions like "I do not know function of this object (picture) - which purpose does it have?"  In many cases I suppose these question could have civil engineering or handcraft i.e. cultural/historical background. In second case "SE history" might be okay. For first case, I do not know. graphics with \setbeamercovered{transparent} With \setbeamercovered{transparent} covered parts of a slide are displayed transparently. If there is a (small) picture among the text, it is shown as it is. Beamer has only this picture, so it shows this picture. My question: How can I give a gray version of the picture to beamer such that in covered parts of a slide, this gray version is used? I have the following pieces of hardware I would like to network mostly for file sharing (media primarily): 1 gaming laptop, 1 i7 (2.3Tb storage) desktop, 1 P4 desktop (500g storage), and 1 250gig PS3.  I am looking to setup a linux host (with a PS3 media server) with the i7 desktop but am concerned about leaving it on all the time. What stripped down, low energy usage distro can I couple with which windows &amp; PS3 friendly software?  Also, how should i reformat my i7 (in terms of partitions, RAID options, whatever)? It has 2 1Tb drives (likely adding a third), and 1 320 gig.