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 v1.0

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This is the release notes for linux release v1.0 (source code: linux-1.0.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 original ASCII formatted version is at the end of this post. CHANGES since 0.99 patchlevel 15: removed all the
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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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Generating RSA Private and Public Key Pair in Go Lang?

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How to generate a pair of RSA private and public key in Go lang? Go lang has a rich set of standard libraries. Using Go’s standard libraries, we can generate RSA private and Public keys. The Crypto standard libraries in Go lang Go lang standard libraries has a rich set of cryptography functions. Here are
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Make Grub2 Boot Older Kernel Version in Ubuntu 20.04

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In a Linux system, we may have multiple kernels installed. Usually, it is the latest kernel configured to be the default one the system boot loader will use during automatic boot if there is no manual kernel choosing. In many cases, such as there is no driver ready yet for some devices in newer kernels,
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How to enlarge root partition and filesystem size of cloud Linux VM at runtime without rebooting Linux

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It is common that the root disk space is not enough when running a Virtual Machine in the cloud such as Amazon Web Service (AWS). The cloud storage usually provides tools or facilities to enlarge a virtual disk size. However, to make the Linux recognize and and use the enlarged disks without rebooting the OS,
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How to exclude a package from a specific repository only in yum?

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This post https://www.systutorials.com/1661/making-dnf-yum-not-update-certain-packages/ introduces how to exclude a package from yum. But is it possible to exclude a package from a specific repository only? For example, a repository R1 I am using contains an updated version of gdb while I don’t want to use the gdb from it as I trust the version (although older)
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`readlink -m` equivalent function in Python to get canonical file name

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readlink -m can get canonical file name by resolving every symlinks in every component of the given path recursively. In Python, the os.readlink() function does not do so. Any equivalent function in Python to the readlink -m command line? Specifically, it does: canonicalize by following every symlink in every component of the given name recursively,
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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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In Python, `os.makedirs()` with 0777 mode does not give others write permission

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In Python, os.makedirs() with 0777 mode can not give others write permission The code is as follows $ python Python 2.7.5 (default, Aug 4 2017, 00:39:18) [GCC 4.8.5 20150623 (Red Hat 4.8.5-16)] on linux2 Type “help”, “copyright”, “credits” or “license” for more information. >>> import os >>> os.makedirs(“/tmp/test1/test2”, 0777) >>> The created dirs are not
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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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For QEMU/KVM, how to share data between host and guest

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General question for developers to access data between VM and VMM. As I know, paravirtualization solution is a good way to share data for VM and VMM since it has better performance. Please use Virtio 9p solution for QEMU/KVM. Note that you need to load 9p related modules for guest kernel. Add following in your
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Cannot make directory ‘/var/run/screen/S-apache’: Permission denied

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Hello! Im trying to create a screen folder for the user apache, Not root. But it seems to fail, I have no idea on how to fix this issue. I only get the error: Cannot make directory ‘/var/run/screen/S-apache’: Permission denied Im using Cent OS 7 There may be various possible reasons. 2 common reasons: screen
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