Zlib is a popular open-source compression library used by many software applications to compress and decompress data. It provides fast and efficient compression and decompression algorithms that can be used to reduce the size of data, which can improve performance and reduce storage requirements. In this post, we will discuss how to install zlib in
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Tag: sudo
.docx/.doc to .odt File Conversion in Command Line in Linux
Posted onWord .docx and .doc files are common for documents commonly generated by MS Word software. We would like to convert them to the more open ODF Open Document .odt files for various cases. This can be done by GUI software tools. If we have a set of many .docx/.doc files, it will be handy if
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Installing R and RStudio Desktop in Ubuntu Linux
Posted onWe 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,
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Installing R and RStudio Server in Ubuntu Linux
Posted onR 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
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Linux User Group Management and Operations
Posted onLinux 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
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Compress PNG Images on Linux
Posted onPNG 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
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Change Another Process’ Environment Variables in Linux
Posted onEach 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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Make Grub2 Boot Older Kernel Version in Ubuntu 20.04
Posted onIn 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 Install Hyperledger Fabric 2.0 in Ubuntu 18.04
Posted onHyperledger 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
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How to Install Go 1.13.x on Ubuntu 18.04
Posted onIn Ubuntu 18.04 LTS, the default Go lang version is 1.10. For compatibility reason, the Ubuntu LTS will usually keep the major release version numbers for packages. However, many applications, such as Hyperledger Fabric 2.0, require a newer version of Go. In this post, let’s take a look at how to install a system level
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How to Install Wine 32-bit on CentOS 8
Posted onSince 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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Generating a Pair of RSA Private and Public Keys in Linux using OpenSSL
Posted onRSA (Rivest–Shamir–Adleman) is a widely used public-key cryptosystem that is used for secure communication over the internet. In this post, we will explore how to generate a pair of RSA private and public keys in Linux using the OpenSSL library. Generating a pair of RSA private and public keys in Linux using OpenSSL is a
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How to Statically Link OCaml Programs
Posted onStatic linking is preferred for some cases although it has its own various problems. Static building/linking is not always possible for some languages on some platform. For OCaml, the answer to this question is yes. In this post, we will introduce 2 methods to statically linking OCaml: static linking with runtime glibc required and static
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How to write to remote side with sudo in rsync?
Posted onHere is the case, the user can not write directly to the remote side’s directory, while the user can sudo on the remote side and write the directory with sudo. How to write to remote side with sudo in rsync? On the source machine, run the rsync command with –rsync-path="sudo rsync" added. For example, rsync
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How to write file content with sudo in Vim?
Posted onVim opens file even if the user does bot have write permission to the file. But after revision, how to write file content with sudo in Vim if Vim reports no permission to write the file. Use this command inside of vim to write to the file with sudo: :w !sudo tee % Here, !
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How to do screen recording on Wayland in Linux?
Posted onHow to do screen recording on Wayland in Linux? Many screen recorders do not work on the new Wayland. Using Green Recorder You may try Green Recorder which supports Wayland. Note: Green Recorder is no longer under development by the original author (Please check the project README for more details). It still works well for
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How to synchronize Google Drive and Google Docs files in Ubuntu/Debian/Mint Linux using Insync
Posted onGoogle Drive is a nice cloud storage service. It provides a suite of nice online document spreadsheet and slide editors Google Docs, Google Sheets and Google Slides. The collaborative editing and full history tracking features of Google Docs are excellent. Google Drive gives 16GB free storage which is pretty much larger compared to other free
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How to enable user themes in Ubuntu 18.04?
Posted onThe way for Ubuntu 17 to installing the gnome-shell-extensions package does not work any more for Ubuntu 18.04. How to enable user themes in Ubuntu 18.04? The updated gnome-shell-extensions package actually adds the User Theme extension back. You can use that. First, install the package sudo apt install gnome-shell-extensions Second, log out and login again
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Fixing the huge emoji icons in Unbuntu 18.04 for Thunderbird
Posted onIn Ubuntu 18.04, Thunderbird shows huge emoji icons in the email list. The emoji covers other text and is several lines higher and wider than other charactors. How to solve it? This is likely caused by the fonts. Find out the *emoji* fonts installed in your system by sudo apt list *emoji* and remove those
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How to change the logo shown during booting in Ubuntu?
Posted onHow to change the logo shown during booting in Ubuntu? I originally installed Ubuntu MATE 18.04. But I am using GNOME 3 now by replacing the DE. But the log shown during booting is still Ubuntu MATE’s. How to change it to another one? It is plymouth the application that manages the “splash” screen during
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