Running Ephemeral Docker Containers – Automatically Remove a Docker Container After Running It

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Docker is a convenient tool to quick create containers from different Linux images. If we use the common way to start a docker container like docker run image bash, after the the process exists, the container is still stored there. That is, the docker container persists after it has exited. Sometimes, we would like to
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Linux Kernel 4.9.60 Release

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This post summarizes Linux Kernel new features, bugfixes and changes in Linux 4.9.60 Release. Linux 4.9.60 Release contains 24 changes, patches or new features. In total, there are 64,224 lines of Linux source code changed/added in Linux 4.9.60 release compared to Linux 4.9 release. To view the source code of Linux 4.9.60 kernel release online,
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Release Notes For Linux v2.0

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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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Linux Kernel: Add support for using a MAX3421E chip as a host driver

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This change “Add support for using a MAX3421E chip as a host driver.” (commit 2d53139) in Linux kernel is authored by David Mosberger <davidm [at] egauge.net> on Mon Apr 28 22:14:07 2014 -0600. Description of “Add support for using a MAX3421E chip as a host driver.” The change “Add support for using a MAX3421E chip
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Linux Kernel 4.19.70 Release

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This post summarizes new features, bugfixes and changes in Linux kernel release 4.19.70. Linux 4.19.70 Release contains 95 changes, patches or new features. In total, there are 101,521 lines of Linux source code changed/added in Linux 4.19.70 release compared to Linux 4.19 release. To view the source code of Linux 4.19.70 kernel release online, please
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Change Another Process’ Environment Variables in Linux

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Each process has its environment variables in Linux. But is it possible to change another process’ environment variable from another process in Linux? If it is possible to do so, how to do it? There is a trick which can work for some scenarios. First, find out the process ID, then start gdb and attach
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How to Install Wine 32-bit on CentOS 8

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Since version 7, RHEL and CentOS only have 64 bit versions. For some reasons, it’s better to run many Windows applications under 32 bit wine. Like How to Install Wine 32-bit on CentOS 7, this post introduce how to install 32-bit Wine on CentOS 8. Most of the mechanisms are similar yet there are differences.
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A StoneWall Solution in C++

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StoneWall is an interesting problem that requires some brain cycles yet not too complex. It is good software engineer interview question. Here is a C++ solution whose complexity is O(N). #include <stack> int solution(std::vector<int> &H) { int stones = 0; std::stack<int> heights; for (auto h: H) { while (!heights.empty() && h < heights.top()) { heights.pop();
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What Are the Secrets Behind Google’s Success Story?

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Google has created an image that tells us its core values are centered around innovation. There are very few companies that can boast a similar level of influence as Google. Nevertheless, we should not only focus on Google’s achievements today but also learn from their journey to the top. We can break down Google’s core
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What is the Future of Big Data Analytics and Hadoop?

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Big Data has taken a lead in the IT industry and has played a significant role in the Business growth and decision-making processes that gives you an edge over the competitors. This is equally applicable to the organizations as well as professionals existing in the analytics domain. Big Data Analytics bring an ocean of opportunities
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5 necessary PC hardware that a programmer needs to upgrade

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The world of technology has evolved drastically over the last few decades. Almost every aspect of our lives is dominated by technology. At the heart of technology lies computer programming. Computer programming is what dictates the success of the technology. I mean think about it, your smartphone, PC, ETC they all rely on programming. This
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New Linux Kernel 5.0: Features and Improvements

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Linux is the most used and well-known open-source operating system for computers, mobile devices, servers, and mainframes, etc. Linux has so many awesome features to serve its users like Live CD/USB. And it is fast, easy and free to use by computers around the world. The kernel is referred to as the essential component of
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How to judge whether its STDERR is redirected to a file in a Bash script on Linux?

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Within a Bash script, how to judge whether its STDERR is redirected to a file in Bash on Linux? For example, ./script.sh /tmp/log 2>&1 Can script.sh detect that its STDERR is redirected? Knowing the destination file is better. To test whether a script’s STDERR (or STDOUT) is redirected to a file, check by [[ -f
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What is the difference between work conserving I/O scheduler and non-work conserving I/O scheduler?

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What is the difference between work conserving I/O scheduler and non-work conserving I/O scheduler? In a work-conserving mode, the scheduler must choose one of the pending requests, if any, to dispatch, even if the pending requests are far away from the current disk head position. The rationale for non-work-conserving schedulers, such as the anticipatory scheduler
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How to get processes’ I/O utilization percentage

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Two notices: 1, a process has only one main thread which is itself. 2, a process has many threads. Solution 1: Please use taskstats [1] related interfaces, and send TASKSTATS_TYPE_PID and TASKSTATS_TYPE_TGID commands to kernel to get a process’s ‘blkio_delay_total’ parameter for a process with one main thread and a process with threads separately. Solution
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Where is MySQL / MariaDB storage location by default on CentOS 7?

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Where is MySQL / MariaDB storage location by default on CentOS 7? No special configuration to the MariaDB from official repository of CentOS. On CentOS 7 Linux it is usually by default /var/lib/mysql But here I give you another “hacky” way to find it out. The method is to find out the mysql daemon mysqld’
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