Git tracks changes as commits. This makes it possible and convenient to check the code change history in a repository. However, this also has side effect. The history consumes storage and the whole repository including the current version of the code files and all the previous changes may be quite large. This is especially a…
Git submodule is a nice and convenient mechanism in Git to include the other Git repositories and manage the version/commit used from the submodule Git repository. However, there are cases where we would like “reset” the submodule, such as when we find updating a submodule repository will break the code tree, or merge some updates…
We ever discussed How To Install R and RStudio Desktop in Ubuntu Linux 20.04. In this post, we introduce how to install R and RSTudio Desktop on macOS. Install R environment Install R environment as follows using Homebrew. $ brew install R Then verify that the R environment is installed and ready, by running in…
It is common to convert an integer (int) to a string (std::string) in C++ programs. Because of the long history of C++ which has several versions with extended libraries and supports almost all C standard library functions, there are many ways to convert an int to string in C++. This post introduces how to convert…
Having a reading list from RSS feeds is a convenient way to organize and aggregate various information source from the Web. After Google Reader was retired, many different readers services are available. Feedly and Follow.it are two good choices among those RSS feed readers. Different readers have different features. Follow.it provides features like keyword filtering…
We ever discussed How To Install R and RStudio Server in Ubuntu Linux 20.04. If the purpose is to install a local RStudio IDE instead of a remote RStudio Server, we can install RStudio Desktop. In this post, we introduce how to install R and RStudio Desktop on Ubuntu Linux 20.04. For other Ubuntu version,…
R is a language and environment for statistical computing and graphics, providing a wide variety of statistical and graphical techniques. The R environment is open source software under GPL. R has rich software packages and is widely used for statistical analysis. RStudio Server is an R integrated development environment (IDE) that provides many useful features…
This change “drm/i915/guc: Don’t enable GuC/HuC in auto mode on pre-Gen11” (commit 87d855e) in Linux kernel is authored by Michal Wajdeczko <michal.wajdeczko [at] intel.com> on Fri Jul 12 11:14:44 2019 +0000. Description of “drm/i915/guc: Don’t enable GuC/HuC in auto mode on pre-Gen11” The change “drm/i915/guc: Don’t enable GuC/HuC in auto mode on pre-Gen11” introduces changes…
This change “PM / clk: Fix clock error check in __pm_clk_add()” (commit 3fc3a0b) in Linux kernel is authored by Geert Uytterhoeven <geert+renesas [at] glider.be> on Fri May 8 10:47:43 2015 +0200. Description of “PM / clk: Fix clock error check in __pm_clk_add()” The change “PM / clk: Fix clock error check in __pm_clk_add()” introduces changes…
This change “netpoll: fix netconsole IPv6 setup” (commit 00fe11b) in Linux kernel is authored by Sabrina Dubroca <sd [at] queasysnail.net> on Thu Feb 6 18:34:12 2014 +0100. Description of “netpoll: fix netconsole IPv6 setup” The change “netpoll: fix netconsole IPv6 setup” introduces changes as follows. netpoll: fix netconsole IPv6 setup Currently, to make netconsole start…
This change “cifs: release auth_key.response for reconnect.” (commit f5c4ba8) in Linux kernel is authored by Shu Wang <shuwang [at] redhat.com> on Fri Sep 8 18:48:33 2017 +0800. Description of “cifs: release auth_key.response for reconnect.” The change “cifs: release auth_key.response for reconnect.” introduces changes as follows. cifs: release auth_key.response for reconnect. There is a race that…
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…
This change “ALSA: hda/realtek – Fix Headphone Mic doesn’t recording for ALC256” (commit d32b666) in Linux kernel is authored by Kailang Yang <kailang [at] realtek.com> on Thu Apr 23 15:10:53 2015 +0800. Description of “ALSA: hda/realtek – Fix Headphone Mic doesn’t recording for ALC256” The change “ALSA: hda/realtek – Fix Headphone Mic doesn’t recording for…
This change “fs: handle SEEK_HOLE/SEEK_DATA properly in all fs’s that define their own llseek” (commit 06222e4) in Linux kernel is authored by Josef Bacik <josef [at] redhat.com> on Mon Jul 18 13:21:38 2011 -0400. Description of “fs: handle SEEK_HOLE/SEEK_DATA properly in all fs’s that define their own llseek” The change “fs: handle SEEK_HOLE/SEEK_DATA properly in…
Git’s tags are convenient use to name some specific commits by tagging them for releasing or book keeping purposes. For example, GitHub allows repository managers to make releases using git tags. However, it may happen by mistake that a git tag is pushed to the remote git server while the tag has been made to…
Counting the number of words in a file is useful in many programs. In this post, we will discuss how to count the number of words in a file in a PHP script. In PHP standard library, we have function str_word_count($str) which returns the number of words from a string $str. On the other hand,…
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…
Linux allows more than one users to log into the system to run processes/programs at the same time. In order to make this multi-user system work properly, Linux provides ways to isolate and protect users from each other and manage the permissions efficiently. One of the mechanism is user groups. Linux users may be grouped…
PNG images already use DEFLATE data compression algorithm involving a combination of LZ77 and Huffman coding. But the PNG images can be further compressed by removing non-important metadata or using lossy compression to save storage space and/or data transfer bandwidth. In this post, we introduce 2 compression ways with tools available on Linux. Lossless compression…
Python is one of the most popular programming languages in the world. It is widely popular for a plethora of tasks due to its flexible nature and ease of use. Python has also managed to beat other programming languages such as Java, which were once upon a time, the world’s favorite. In fact, the extent…