How to convert .pptx slides to .jpg or .png images on Linux in command line? This following method works best for me. First, convert .pptx file to .pdf using libreoffice: libreoffice –headless –convert-to pdf file.pptx –headless makes libreoffice run in batch mode and not start the GUI. The pdf file will be named file.pdf by
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Category: Tutorial
How to merge git branches quickly and correctly
Posted onSuppose I have following branches harryxiyou@common_vm ~/forest/sqle/sqle/scripts $ git branch * dev-harry master rc After I did some changes on dev-harry branch, I wanted to merge dev-harry into rc branch. 1, git checkout rc 2, git merge dev-harry References:http://stackoverflow.com/questions/24147169/merge-two-remote-branches-in-githttps://www.atlassian.com/git/tutorials/using-brancheshttp://git-scm.com/book/en/v2/Git-Branching-Basic-Branching-and-Merging I usually add –no-ff during git merge to force git to add a commit for the
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How to build mplayer with libdvdnav on Linux?
Posted onI find the mplayer from rpmfusion does not contain libdvdnav. How to build mplayer with libdvdnav on Linux? I did this on Fedora 21 to build mplayer with libdvdnav: Download mplayer src from http://www.mplayerhq.hu/design7/dload.html and extract the tarball. Install needed packages (you will need more if you need more features): # yum install gcc make
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How to make dd faster on Linux?
Posted ondd seems slow when I use command like # dd if=/dev/sda2 of=./sda2.bak How to make it faster? You can make dd faster by specifying a good bs like # dd if=/dev/sda2 of=./sda2.bak bs=8192 8192 is a magic number. There are may be other good sizes for bs for different systems. But 8192 works pretty well
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How to understand some key system consistency algorithoms
Posted onWhen we design a system, we may want our systems to be consistency, scalability and so on. Currently, there are some famous consistency algorithms. How to understand them easily. 1, Paxos and its extensions 2, Replicated State Machine mechanisms 3, Quorum Welcome to adding other famous consistency algorithms and its understanding ;-) Reading text books
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When should the authors anonymize themselves in a paper submitted to a conference for review?
Posted onWhen should the authors anonymize themselves in a paper submitted to a conference for review? Several general concepts: Peer review is the evaluation of work by one or more people of similar competence to the producers of the work (peers). — Wikipedia Single-blind describes experiments where information that could introduce bias or otherwise skew the
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How can I recover deleted photos from samsung?
Posted onHow can I recover deleted photos from samsung? You may try PhotoRec. A step by step tutorial can be found here. There are similar software. You can google them. Have you retrieved your lost photos from Galaxy? If not, you can follow the steps below to get some back. Hope it helps you somewhat. Stop
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How to filter RSS feed items?
Posted onHow to filter RSS items and leave only certain items that I want? Rules may be like: satisfies all or any rules { contains keyword; does not contain keyword } or etc. Two sServices that I find working well for me: Yahoo Piples: https://pipes.yahoo.com/pipes/</s> Pipes is a powerful composition tool to aggregate, manipulate, and mashup
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How to measure a function’s execution time in OCaml?
Posted onHow to measure the execution time of a function, say f: ‘a -> ‘b in OCaml? This small OCaml function is handy: let time f = let t = Unix.gettimeofday () in let res = f () in Printf.printf “Execution time: %f secondsn” (Unix.gettimeofday () -. t); res ;; The gettimeofday returns a float representing
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How to display chinese character in lxterminal
Posted onDo you know how to display chinese character in lxterminal? I tried to install lxterminal on my workstation and it seems display Chinese characters well: FYI, my Linux system is Fedora 21. The lxterminal version: $ rpm -q lxterminal lxterminal-0.1.11-10.fc21.x86_64 Not sure what’s the reason why it does not work for you. You may check
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How to list all running system service on Linux Mint 17.1?
Posted onHow to list all running system service on Linux Mint 17.1? You can use initctl to list all services: initctl list
Basic iptables configuration for Linux
Posted onWhat is a good basic iptables config? Basic rules needed: Allow incoming TCP to 22 for SSH but blocks all others. Allow outgoing TCP/UDP connections. You may consider using the following rules as a start: for tables in iptables ip6tables ; do # Flush existing rules $tables -F # Default policy $tables -P INPUT DROP
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How to log connections hitting certain rules in iptables on Linux?
Posted onHow to log connections hitting certain rules in iptables on Linux? Like the one that are dropped because of too frequently creating SSH connections. You can create a new chain named LOGNDROP that log the connections and drop them, then pass the connection to be redirected to the LOGNDROP chain. $tables -N LOGNDROP # Connections
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How to use iptables to limit rates new SSH incoming connections from each IP on Linux?
Posted onHow to use iptables to limit rates new SSH incoming connections from each IP on Linux? For example, at most 6 SSH connection attempts every 60 seconds. You may use these rules (skip the first one, if you have set the basic rules): for tables in iptables ip6tables ; do # Allow established inbound connections
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How to configure iptables on Linux Mint 17.1?
Posted onHow to configure iptables and make the configuration persistent across system restarting on Linux Mint 17.1? You can use the ‘iptables-persistent’ tool. To install iptables-persistency pachage: sudo aptitude install iptables-persistent The you can manipulate the iptables by the ‘iptables’ command. To save the current iptables rules: sudo /etc/init.d/iptables-persistent store It will store the rules for
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How to upgrade packages installed by ELPA in Emacs?
Posted onELPA manages packages for Emacs nicely. But, how to upgrade packages installed by ELPA in Emacs? Within Emacs, list all packages by M-x list-packages and it will automatically refresh the archive contents. Then, press U to mark all upgradable packages to be upgraded. Last, press x to perform the new updates. Emacs will then download
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How to install musl libc on Linux Mint 17?
Posted onHow to install musl libc on Linux Mint 17/Ubuntu 14.04? You can install musl libc on Linux Mint 17 by sudo aptitude install musl musl-dev musl-tools One note: If you want to install a newer version of musl libc than the one from Ubuntu repo, you can use this ppa: https://launchpad.net/~bortis/ archive/ubuntu/musl by sudo add-apt-repository
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Find Available Packages Versions using aptitude in Ubuntu
Posted onHow to find the available packages’ versions with aptitude on Linux? With aptitude, you can use this command to show the available versions of a package: aptitude versions <package name> In the console GUI, aptitude also show the versions. You may also simulate installation of a package and see which version will be installed: aptitude
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How to make Alt key work in xterm?
Posted onAlt key seems not work in xterm. Alt is important for Emacs. How to make Alt key work in xterm? Put this in your ~/.Xresources file: XTerm*eightBitInput: false XTerm*eightBitOutput: true Remember to make it take effect after you change the ~/.Xresource without restarting the X server by xrdb -merge ~/.Xresources
How to exclude directories with certain names from rsync on Linux?
Posted onHow to exclude directories with certain names like “cache” from rsync on Linux during backup? The “cache” directory may in many different paths, such as file1/cache/ or file2/cache/, and adding all “cache” directories to rsync command is not a doable way. You can use rsync with –exclude=cache/ like rsync -avxP –exclude=cache/ /path/to/src/directory/ /path/to/dst/dir/