How do I determine the RHEL version by looking at this extraction, I can only know that it is RHEL7 from el7 but what is the exact version?  Command: /bin/uname -a ==================================================== Linux xxxxxxxxx 3.10.0-957.12.2.el7.x86_64 #1 SMP Fri Apr 19 21:09:07  UTC 2019 x86_64 x86_64 x86_64 GNU/Linux
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?
Hill cipher, unknown letter value I've been struggling on this problem for a while now : the Hill cipher is well-known to be vulnerable to known-plaintext attack due to its linearity. Given a key matrix $K$ of size $n\times n$, one can retrieve the key with as little as $n^2$ plaintext/cipher text couples.  All examples found on the Internet assume an alphabet where $A=0, B=1 \dots Z=25$, but how could we break the Hill cipher using a know-plaintext attack without any clue over the alphabet permutation nor the key matrix ?  I've tried several things such as  the whole set of equations together, however it requires several divisions in $\bf{Z}_{26}$ which aren't possible (i.e. division by even numbers or 13) Is there a way to simulate a numeric keypad on apple wireless keyboard in OSX? I'm tempted to get an Apple Wireless Keyboard but the lack of a number pad is a concern. I'm interested whether there is some form of software you can use where for example you hold some control keys down and you can use a set of keys like the following as a substitute numeric keypad:   7890 uiop jkl; m ./ Question:  Show that $n^2 + 3n + 5$ is not divisible by $121$, where $n$ is an integer. Surprisingly many network interfaces on macOS: are these legitimate? ifconfig reveals a surprisingly long list of network interfaces on my MacBook, which is running macOS High Sierra (10.13.6): lo0, gif0, stf0, XHC20, en0, p2p0, awdl0, en1, en2, bridge0, utun0.  There is an F5 VPN client installed, but I've rebooted the MacBook since the last VPN connection.  Are all of these network interfaces legitimate or is this something I should worry about? no wifi in Ubuntu 15.04 I cannot see WiFi option in my Ubuntu 15.04. What should I do? Revert asap  lspci -nnk | grep 0280 -A2 output:-  03:00.0 Network controller [0280]: Qualcomm Atheros Device [168c:0042] (rev 30) Subsystem: Foxconn International, Inc. Device [105b:e09a]   rfkill list output:-  0: hci0: Bluetooth Soft blocked: no Hard blocked: no 1: acer-wireless: Wireless LAN Soft blocked: no Hard blocked: no      dmesg | grep ath [    9.545199] ath10k_pci 0000:03:00.0: pci irq msi-x interrupts 8 irq_mode 0 reset_mode 0 [   10.029684] ath10k_pci 0000:03:00.0: Direct firmware load for ath10k/cal-pci-0000:03:00.0.bin failed with error -2 [   10.029701] ath10k_pci 0000:03:00.0: Direct firmware load for ath10k/QCA9377/hw1.0/firmware-5.bin failed with error -2 [   10.029704] ath10k_pci 0000:03:00.0: could not fetch firmware file 'ath10k/QCA9377/hw1.0/firmware-5.bin': -2 [   10.029711] ath10k_pci 0000:03:00.0: Direct firmware load for ath10k/QCA9377/hw1.0/firmware-4.bin failed with error -2 [   10.029713] ath10k_pci 0000:03:00.0: could not fetch firmware file 'ath10k/QCA9377/hw1.0/firmware-4.bin': -2 [   10.029719] ath10k_pci 0000:03:00.0: Direct firmware load for ath10k/QCA9377/hw1.0/firmware-3.bin failed with error -2 [   10.029721] ath10k_pci 0000:03:00.0: could not fetch firmware file 'ath10k/QCA9377/hw1.0/firmware-3.bin': -2 [   10.029726] ath10k_pci 0000:03:00.0: Direct firmware load for ath10k/QCA9377/hw1.0/firmware-2.bin failed with error -2 [   10.029728] ath10k_pci 0000:03:00.0: could not fetch firmware file 'ath10k/QCA9377/hw1.0/firmware-2.bin': -2 [   10.029733] ath10k_pci 0000:03:00.0: Direct firmware load for ath10k/QCA9377/hw1.0/firmware.bin failed with error -2 [   10.029735] ath10k_pci 0000:03:00.0: could not fetch firmware (-2) [   10.029737] ath10k_pci 0000:03:00.0: could not fetch firmware files (-2) [   10.029739] ath10k_pci 0000:03:00.0: could not probe fw (-2) Automatically make various multiple stroke colour the same as various underlying fill colours. I have auto traced a photograph in illustrator - its got thousands of vectors once I expand it and illustrator has converted each of them to a filled colour - I want to now trace the edges of them with a grungy brush but using the underlying fill colour. Where in illustrator can I stroke or outline these fills using the underlying colour - surely this is something that the program automatically does?   I've found this script online but don't know how to implement it. I'm new to this so any help appreciated. Many thanks.   James   var idoc = app.activeDocument;   var sel = idoc.selection;    for (i=0; i&lt;sel.length; i++) {       var ipath = sel[i];       ipath.stroked = true;       ipath.strokeColor = ipath.fillColor;   } Denoting the end of example/remark What is the etiquette to denote the end of an example or remark? For proofs, it's the QED symbol (white box). I know it's not necessary for everyone, but I would like to use it to break up the text a little. What should I use? A circle or filled box or what? GridBox/packed array behaviour Batch normalize audio volume on .ogg-files Are there any simple tools to normalize an .ogg-library of 10'000+ songs so that the volume is the same throughout all songs?  Terminal or GUI doesn't matter, it only need to be simple.  One caveat though, I don't want soft interludes/intermissions and ballads blown out of proportion.  Preferably the process should find the overall gain of the album (I have all my CD's ripped into separate folders) and normalize the level thereafter. Ubuntu 14.10 folder icons missing I have already read the question about  but this is not what I want, I want to be able to click on the file in Dash or in Nautilus and be able to open it with the specified app.  For example I have this case right now:  When I click on an EXE file it does not get executed by Wine, instead I get the following:    If I try to look for Wine in the Open With context menu option it is there. I am fine executing it from there the first time, but then the following times Wine does not appears selected in the main Context menu:    I then went to Properties to the Open With Tab to look for Wine. It was not in the Default apps nor was it in the Recommended ones when I clicked and search on Show other applications    This is not limited to EXE extensions. It also has happened with MKV files, MP4 files, JPG, PNG, MP3 and even SVG and CSS. So instead of trying to find a way of solving it for one, I want a way that can be done to any type of extension that can:   Make the app the default of that extension Appear on the context menu in Nautilus when I right click on the file Appears on the "Open With" tab on the Property window of the file Correctly executes the specified app when I click on the file with Dash   This might sound like it should be common sense for an app to execute the file but it does not always work like that. So for the cases where it actually does not work, how to fix it. A reset of the extension?, An update of the files that can open said extension?, an addition of the app via a command line or GUI tool? There's another question on physics.SE whose , if I have understood it correctly, explains that the farther the points are in space the faster they are moving away from each other.     Actually, the apparent speed with which two of the points on the   circle in a distance $D$ of each other would move relative to each   other will be $v = H_0 D$ where $H_0$ is the speed the balloon itself   is expanding.   This means that even the ruler sitting on my desk is expanding, just that the expansion is very very slow owing to the ruler's small size relative to the cosmic scales. However, if everything is scaling then everything should apparently be of the same size to an observer in such an expanding space. The  quote from the show "The Big Bang Theory" comes to mind.   To be able to counter that, there're some phenomena that we can observe which are scale invariant. Red-shift would be one such phenomenon. But is red-shift the only way we can tell that the space is expanding? Is there a logical flaw in my thinking? I know that red-shift is a result of the Doppler effect - there's bound to be a decrease in the frequency of a signal, as perceived by an observer, emitted by a source which is moving away relative to the observer. How to create subfloat figures (two in first row and one below)? I want to place three figures like this on the page:  (a) (b)   (c)   How do I achieve this using subfloat or any other method in LaTeX? The three figures need to have a common caption and label.  I have tried this:  \begin{figure}[h] \centering \begin{tabular}{c c} \subfloat[] { \includegraphics[scale=0.4]{1.pdf} } &amp; \subfloat[] { \includegraphics[scale=0.4]{2.pdf} } \\ \multicolumn{2}{c} \subfloat[] { \includegraphics[scale=0.6]{3.pdf} } \end{tabular} \caption{Some caption} \label{some-label} \end{figure}   But, this is displaying [] for the third figure instead of (c). Also it displays [] to one side of the page instead of center. Can Debian identify rarely used packages? I'd like to find a tool that could tell me which Debian packages on my system have been rarely or never used, perhaps by looking at file lists and access times.  This is to find candidates for deletion from my nearly full hard drive.  I'm not very well informed about the rich ecosystem of desktop GUI tools (I use aptitude); does anyone know if one of those tools, or any other tool, can identify how recently a package has been used? How to stop Skype from starting automatically when booting Windows 10? Can I pack a cardboard box as checked luggage? As mentioned in , I'm planning on traveling with a desktop computer as checked baggage. After considering the options, I've decided to take it in its original cardboard box (used for shipping), making sure to pad everything inside very well.  What should I do to securely prepare the box before checking it in? Some suggestions others have given me so far:   Spray paint the box black so it's not obvious there's a computer inside. Wrap the entire box with duct tape to reinforce it. Use tape to seal the "hand holes" on either side used for carrying the box. Run packing tape around all the edges to reinforce the box. How does the Eco-Cooler air conditioner really work? describes a device for developing countries which apparently cools the air by 5 °C without electricity. According to , it works by lowering the pressure to drag in the ambient air. Wouldn't the ambient air be at the same temperature?  Does the constriction compress the air and temporarily increase the pressure and so temperature, which then dissipates heat because it is hotter than surroundings; then after passing the constriction, the pressure returns to almost ambient but the temperature drops to below ambient?  How does the Eco-Cooler air conditioner actually work, if at all? How to list files that were changed in a certain range of time? How can I list recursively all files that were changed between 22.12.2011 and 24.12.2011? How to tell what method was used to log in (Password vs. Keyfile) from the bashrc Is there a way how you can check what auth method the user which just logged in to an account were using?  I like to print out a warning after login if someone is using a password instead of a keyfile.  Sure one solution is to check the ssh-logs. But is there a nicer way to do this? Since looking up logs could impact performance depending on the log size and method you use to gather this information.  We are using SUSE and Ubuntu. Logging in as the same user multiple times in Remote Desktop Windows Server 2008 Quick question: I have a situation where I need to let multiple people on different PCs log into one server 2008 machine as administrator simultaneously over remote desktop. I have the CALs for it, it's just not set up correctly. When one user tries to log in, it boots the other out. What I need is to present to them a different session, just each as logged in as admin. Sorry for the slightly rambling post, I'm new here. Thanks!