This is the release notes for linux release v2.0 (source code: linux-2.0.tar.gz) with format adjusted by removing/replacing tabs/spaces/new lines/formatting marks. This notes document can give us an understanding of the early development of the Linux kernel. The original ASCII formatted version is at the end of this post. Intro This document contains a list of
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Tag: Tip
How to put files with spaces in names into HDFS?
Posted onI got this error when I tried to save a file with a space in its name into HDFS: $ hdfs dfs -put -f “/home/u1/testa/test a” “/u1/testa/test a” put: unexpected URISyntaxException while the HDFS seems allow spaces in its file names: https://hadoop.apache.org/docs/r2.7.3/hadoop-project-dist/hadoop-common/filesystem/model.html . How to achieve the effect of saving the files with spaces in
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How to use vnc to connect remote server with GUI desktop
Posted onFor my case, I need to bypass one intermediate server so that I can connect to the remote server with vnc. For example, there are two servers (s1, s2) except my local PC and I have to login to s1 so that I can login s2 from my local PC. However, now, I need to
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How to open a URL in a new window in JavaScript?
Posted onHow to open a URL in a new window in JavaScript? For example, to open a new window to browse “http://www.systutorials.com“. Open the URL in a new window: url = “http://www.systutorials.com”; window.open(url); Some browser will open the window in a new tab depending on the configuration. If you want to force the browser to open
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mkfs refuses to make filesystem with message “is apparently in use by the system; will not make a filesystem here!”
Posted onI have a disk from another server installed on a new server. However, when I try to make a filesystem on it, mkfs reports # mkfs -t ext4 /dev/sdd1 mke2fs 1.42.8 (20-Jun-2013) /dev/sdd1 is apparently in use by the system; will not make a filesystem here! This is a new disk to the new server.
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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 resume a printing job on HP printer if the paper runs out on Linux?
Posted onHow to resume the printing job on HP printers if the paper runs out on Linux? A tip: “lifting the cover to access the toner and putting it down without touching anything else will clear the out of paper error and continue printing” from here.
Good tools to manage OCaml packages
Posted onWhich tools to mange OCaml packages in my system (Linux)? I use OPAM to manage OCaml packages: http://opam.ocamlpro.com/index.html To install it: $ wget https://raw.githubusercontent.com/ocaml/opam/master/shell/opam_installer.sh $ sh ./opam_installer.sh /usr/local/bin More options are available here. To make opam settings take effect, append this to ~/.bashrc: eval `opam config env` Some frequent usages: opam list # List all
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How to revert a merge in Git
Posted onI merge a branch, say b1, from another branch, say b2. Both b1 and b2 have some commits. Say, b1: c1 —> c2 —> c3 b2: c1 —> c4 —> c5 Now, if I merge b2 to b1 and there is no conflicts, b1’s history includes b2’s commits (c4, c5). How to revert this merge
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Where Does Evolution Save Its Data and Configuration Files on Linux?
Posted onEvolution is a great personal information management tool that provides Email, address book and calendar tools. Evolution provides many enterprise friendly feature such as native support to Microsoft Exchange connectivity for Emails, address books and calendars. Evolution uses various ways including plain files and dconf configuration systems. This post will give an introduction to the
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I/O Microscopy: Tasks’ Disk I/O Information with High Accuracy
Posted onAbstract Most popular task monitor systems (such as top, iotop, proc, etc) can only get tasks’ disk I/O information like tasks’ I/O utilization percentage every seconds due to kernel timer/tick frequency and high time cost of system interfaces. This article presents I/O Microscopy, a new way to get tasks’ disk I/O information with high accuracy.
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Essential Gnome Shell Extensions for Gnome 3 Users
Posted onGnome Shell has a clean design. But many users want to get more from the desktop environment. Gnome 3’s extension system can help users customize the Gnome Shell’s look greatly. In this post, we summarize 6 extensions we considered essential to make Gnome Shell great. AlternateTab Make Alt-Tab “classic” instead of grouping windows by application.
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Three Methods of Executing Commands on Many Nodes in Parallel via SSH on Linux
Posted onIt is common to execute commands on many nodes/hosts via SSH for managing a cluster of Linux servers. On Linux, there are many choices for this task. Generally, to run commands on many nodes, there are two modes: serial mode and parallel mode. In serial mode, the command is executed on the node one by
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How to Run a Command Upon Files or Directories Changes on Linux
Posted onDoing actions upon changes of files and directories is very useful. Examples like compiling a project after the source code files are changed, sending emails after important configuration files are modified, building the PDF after a TeX file is modified. On Linux, the inotify-tools provide good support for trigger actions after changes. In this post,
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How to Play YouTube Video in Background on iPhone
Posted onThis post introduces how to play YouTube video in background on your iPhone. With this tip, you will need not to keep the YouTube app opening all the time. So you can use other apps on iPhone while listening to the music or talk or others from YouTube. This tip should also work on other
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Hadoop Installation Tutorial (Hadoop 2.x)
Posted onHadoop 2 or YARN is the new version of Hadoop. It adds the yarn resource manager in addition to the HDFS and MapReduce components. Hadoop MapReduce is a programming model and software framework for writing applications, which is an open-source variant of MapReduce designed and implemented by Google initially for processing and generating large data
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Keyboard Key Mapping for Emacs: Evil Mode and Rearranging Alt, Ctrl and Win Keys
Posted onCtrl keys are important and possibly most frequently used in Emacs. However, it is painful on today’s common PC keyboards since Ctrl keys are usually in the corner of the keyboard main area. Why the key mappings in Emacs are designed like this? After it was designed, Emacs was commonly on the Lisp Machine keyboards
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Improving ssh/scp Performance by Choosing Suitable Ciphers
Posted onUpdate on Oct. 9, 2014: You should be aware of the possible security problems of blowfish and it is suggested not to be used. Instead, you may consider ChaCha20 as suggested by Tony Arcieri. To use this with OpenSSH, you need to specify the Ciphers in your .ssh/config files as chacha20-poly1305@openssh.com possibly with another default
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Making Emacs Start Up Faster
Posted onI use Emacs in terminals and start/close Emacs frequently as needed like in a file checking-editing-closing loop. However, Emacs seems take some time to start up especially some heavy modes are used. How to make Emacs start up faster? (If you just want the solution/script first, find the command in the summary section.) My solution
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Customizing Fonts in Gnome 3
Posted onGnome 3 is great and I can understand that it emphasizes on simplicity. However, the configuration settings for Gnome 3 does not provide tools for certain functions that I need. One of them is customizing the fonts. This post will summarize the tools/tips that I adopted to customize the fonts in Gnome 3. Usually, the
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