As a dedicated macOS user, I often find myself missing the convenience of having a Command key located near my thumb for common shortcuts when using Windows. In the standard Windows keyboard layout, the key that occupies the same position as the Command key on macOS is the Alt key. However, the equivalent key on…
When working on a large-scale C++ project with multiple dependencies, it can be challenging to understand the relationships between different components and libraries. Thankfully, CMake provides a nifty feature to visualize these dependencies using Graphviz, a widely-used open-source graph visualization software. Using CMake’s –graphviz option and the dot command from Graphviz is a powerful way…
Thunderbird is a nice email client and calendar management software. iCloud calendar is the native calendar cloud service in Apple devices such as iPhone. So far there is no native support from Thunderbird to support iCloud calendar, excepting reading the read-only public iCloud calendars which has privacy concerns as long as lacks of editing functionalities….
snap is a software app bundle with dependencies included so that it can works in different Linux distributions. However, as most other software, snap has compatiblity issues. An app in the snap format is not 100% the same and compatible with the native version. One of the problem I find is that Thunderbird from snap…
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…
This is the notes for linux kernel release 0.01 (source code: linux-0.01.tar.gz) with format adjusted by removing/replacing tabs/spaces/new lines. This notes document can give us an understanding of whether the Linux kernel started with its very first release. The original ASCII formatted version is at the end of this post. Notes for linux release 0.01…
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…
DNF/YUM can automatically download the RPM packages and install them. Under some situations, we may prefer to make a copy of the RPM files for offline usage so that no need to have network connections to install the software packages. For such purposes, we need to make a copy of the RPM packages. It is…
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,…
Hyperledger Fabric is a consortium blockchain system. It’s performance is relatively good and its modular architecture enables it to be usable in many scenarios. Hyperledger Fabric itself has rich documents and samples of test networks. For beginners, deploying a new network for trying and testing still consumes quite some time. In this post, we will…
Thunderbird is a nice email client available on Linux and Windows. With the Lightning plugin, Thunderbird can support calendar functions well. Exchange is a widely used email and calendar/address book service software. Office 365 provide the cloud version of Exchange named Office 365 Exchange Online. Although Exchange Online provide IMAP for synchronizing emails, it provides…
How to add Chinese input method, such as Pinyin, to Unbuntu 18.04? To input Chinese, first install an input method framework. Here, we use fcitx. Then you need to input the Pinyin input method. You may use fcitx-sunpinyin. Put them all together $ sudo apt-get install fcitx fcitx-sunpinyin After that, set the default input method…
/dev/shm is a nice in memory disk on Linux. The default size seems half of the physical memory’s size. How to configure shm size of Linux? And what’s the consequence? To change the configuration for /dev/shm, add one line to /etc/fstab as follows. tmpfs /dev/shm tmpfs defaults,size=8g 0 0 Here, the /dev/shm size is configured…
How to disable the fastmirror yum plugin in CentOS 7 Linux? The fastestmirror function of yum is provided by the package `yum-plugin-fastestmirror`. However, because `yum` depends on it, the `yum-plugin-fastestmirror` package can not be removed. If you try to remove it, `yum` will report failures like. # yum remove yum-plugin-fastestmirror Loaded plugins: fastestmirror Resolving Dependencies…
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’…
How to make iptables/ip6tables configurations permanent across reboot on CentOS 7 Linux? CentOS 7 uses FirewallD by default. If you would like to manage iptables/ip6tables rules directly without using FirewallD, you may use the old good iptables-services service which will load the iptables/ip6tables rules saved in /etc/sysconfig/iptables and /etc/sysconfig/ip6tables when it is started during boot…
How to change the maximum uploading size for PHP with Apache on Linux? PHP has parameters to control the maximum uploading size. Here, we use Ubuntu 18.04 LTS default version as an example. First, open the php.ini configuration file using your favorite editor /etc/php/7.2/apache2/php.ini Then, find the following parts ; Maximum size of POST data…
I update libvirt version and want to start VM with the new libvirt tools but I failed as follows. > sudo virsh start kvm1 error: Failed to start domain kvm1 error: Network not found: no network with matching name ‘default’ It seems that the default ‘virbr0’ is missing after I update libvirt so I solve…
Hello, I have installed Xen4Centos on Centos7, having single NIC card with bridge network and have two VMs on that. In one VM, I want to add two static IP one for webserver and one for mail server. So I have created IP alias in guest VM, it was created but it was not pinging…
PARSEC is the most important CPU-bound benchmark for systems. It is huge and hard to install because it needs lots of 3-part libs. PARSEC download link for 3.0 version: http://parsec.cs.princeton.edu/download.htm#parsec I remembered I added the answer yesterday night but I could not see the answer currently. Anyway, let me add the answer again after I…