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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Add Inline Comments for Multi-line Command in Bash Script

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In Bash script, it is common that multiple small commands run together connected by pipes (|) and the whole command is quite long. For clarity, we may write the command in multiple lines. How to add comments for these long multi-line commands? In Bash, the content after # in a line is the comment. Using
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How to Match Multiple Lines using Regex in Perl One-liners

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Perl one-liners with perl’s regular expression statement can be a very powerful text processing tools used as commands in a terminal or a script. By default, the input to the perl one-liner with -p or -n options is passed line by line. However, when we want to match multiple lines, it gets us some trouble.
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How to Query Transaction By ID in Hyperledger Fabric 2.0

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Querying transaction content out from a blockchain network is a common practice used by common scenarios like exploring the blockchain history or verifying the blockchain transaction content from a known ID. In Hyperledger Fabric, the transaction can be queried using a special system chaincode QSCC (Query System Chaincode) which is for ledger and other Fabric-related
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How to Install Hyperledger Fabric 2.0 in Ubuntu 18.04

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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
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How to Install Go 1.13.x on Ubuntu 18.04

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In 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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Bash Learning Materials

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Bash (GNU Bourne-Again SHell) the default shell for many Linux distributions. It is very common for scripting languages in Linux. Bash is easy and straightforward for writing small tools. However, as most tools, it has its grammars that could easily cause bugs if they are not used correctly. Here I summarize a list of good
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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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Killing Running Bash Script Process Itself and All Child Processes In Linux

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In Linux, how to kill a process and all its child processes? For example, a Bash script A starts B, B starts C and C calls rsync. I would like to kill A and all its child processes all together. How to do this? There are possibly many answers to this question. One of the
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How to delete or get the number in the tail from a string in shell script?

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How to delete or get the number in the tail from a string in shell script (bash script)? Okay to call other tools. For example, from “/dev/sda8”, I want to get “/dev/sda” and “8” separately. This can be achieved by using sed as follows. To get the string after deleting the tailing numbers, we can
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Any good Go REPL implementation / tool?

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Go lang is fast to compile and can be used as a script by go run prog.go. However, a REPL is more convenient for testing/trying some small pieces of code. Any good Go REPL implementation / tool? Try gore https://github.com/motemen/gore Get gore $ go get -u github.com/motemen/gore An example $ gore gore version 0.2.6 :help
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How to get the full path and directory of a Makefile itself?

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How to get the full path and directory of a Makefile itself like finding Bash script’s own path? This 2 lines in Makefile get the full path and dir of the Makefile itself: mkfile_path := $(abspath $(lastword $(MAKEFILE_LIST))) mkfile_dir := $(dir $(mkfile_path)) The piece of code gets you Makefile, finds its absolute path and the
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