3 Ways of .odt to .txt File Conversion in Command Line in Linux

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The Open Document .odt files can contain rich formats for the content. However, some times a plain text file is more handy. We may convert .odt files to plain text files for such needs. In this post, we discuss 3 ways of how to convert .odt files to .text files in command line in Linux.
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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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Release Notes For Linux v0.95a

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This is the release notes for linux release v0.95a (source code: linux-0.95a.tar.gz) with format adjusted by removing/replacing tabs/spaces/new lines. This notes document can give us an understanding of the early development of the Linux kernel. The the formatted version of the referenced RELNOTES-0.95 can be found at Release Notes For Linux v0.95. The original ASCII
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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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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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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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How can I login without password and run command in server at a local machine remotely?

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Login without PWD is fast and efficient. Running commands in server from local machine also have these benefits. login without PWD: add PC A’s public key to PC B’s authorized keys. > a@A:~> cat .ssh/id_rsa.pub | ssh b@B ‘cat >> .ssh/authorized_keys’ > b@B’s password: Run command remotely ssh root@MachineB “ls” NOTE: running commands remotely is
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How to check interrupts lively in your systems?

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I need to see what kind of interrupts are handled by which CPU. Please run command: # cat /proc/interrupts or you can execute $ watch -n1 “cat /proc/interrupts” to watch interrupts every 1 second. See [1] [2] for more details. References: [1] https://stackoverflow.com/questions/28301875/how-to-observe-interrupts-in-windows-or-linux-ubuntu-14-04 [2] http://www.linuxjournal.com/content/watch-live-interrupts

How to tune systems to achieve high performance in virtualization circumstances?

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Most time, we need to tune system parameters to achieve better performance but what the general parameters to be tuned in Linux systems. I think you may want to add following parameters to Kernel boot (/etc/default/grub) parameters intel_idle.max_cstate=0 processor.max_cstate=0 idle=poll intel_pstate=disable At the same time, you may also want to shutdown/open Pause Loop Exiting (PLE).
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How to get vCPU thread ID in QEMU/KVM host OS?

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In order to collect more information about CPU information internal guest OS, we usually need to get vCPU’s thread ID in host OS. Solution 1: Under directory ‘/sys/fs/cgroup/cpuset/machine’, you will find virtual_machine_name.libvirt-qemu directory. And under this directory, you will find all vCPU sub-directories and under these dirs, you will find vCPU thread IDs. For example
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How to print a line to STDERR and STDOUT in C++?

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In C++, how to print a string as a line to STDOUT? That is, the string and the newline character, nicely? And similarly, how to print the line to STDERR? In C++, you may print the string and then ‘n’ or std::endl to STDOUT by operating on the std::cout stream: std::cout << your_string << std::endl;
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