17.2.2 Package Management Tool – dpkg
The “dpkg” tool is the software based on Debian’s package management system, which is used to install or remove “.deb” packages and provide information about packages.
The “dpkg” package includes the various programs together needed to actually run the packaging system, such as “dpkg-deb”, “dpkg-split”, “dpkg-query”, “dpkg-statoverride”, “dpkg-divert” and “dpkg-trigger” as well as the “dpkg” program.
17.2 Package Management Tool
17.2.1 Overview of the Package Management Tool
There are several tools for managing packages in Debian. All of these management tools have features, so you can choose the one that suits your needs.
These management tools can be classified into various types according to their characteristics. First, it can be divided into several layers according to the processing function and complexity level of the package management tool:
17.1.2 Package Repository
The Debian-based distribution manages the basic program list information that can be installed and used on the system where the operating system is installed. This is called the package repository. The Debian-based distribution runs the package repository server on Internet and provides a package management system called Advanced Packaging Tool (APT), a tool for searching, installing, and manipulating packages in the package repository.
17.1.3 Package Manager System
A package manager or package management system means a set of software tools that consistently automate the process of installing programs, upgrading programs, adjusting setting item, and deleting programs on a particular computer operating system. Debian uses a package manager system to unify all the software packages installed on the system into one and manage them integrally.
17.1.4 Source List of Package Repository
The place to specify where the package manager should download information about the package is called the source list. The APT tool in Debian determines the source list to download the package from “/etc/apt/sources.list” file. CD-ROM, HTTP server, FTP server, and hard disk can all be sources.
17.1.5 Naming Rules for Package
The package usually has a filename in the form of a “deb” extension. “deb” is an extension to the Debian software package format, which is used for binary packages. The basic format of package file name is as follows.
17.1 Package Manager System
17.1.1 Package
Package is a set of files in which all the necessary data is organized in a predefined way so that the program can be distributed and installed in the manner required by the system. The package contains the metadata needed to apply the program as well as the computer program. Package metadata also has the information about a description and version of the package, and dependencies with other packages (relationship with other packages that must be installed first) together.
Chapter 17 Program Installation & Upgrade
Chapter’s Main Topics
This chapter describes the procedure for installing additional programs in the Raspberry Pi system. It also explains how to remove or upgrade previously installed programs.
It includes descriptions on the following topics:
■ Package manager system
■ Package management tool
■ Obtaining installer program source
■ Installing and reinstall program
■ Uninstalling program
■ Update and upgrade of program
■ Upgrade system kernel and firmware
16.2.3 Creating Text File
There are many ways to create a text file in Raspberry Pi. There is a method to create it from the Shell Terminal, and a method to process it from the Desktop window.
There are several ways to create simple text files from the Shell Terminal as shown below:
16.2.2 Renaming Directory and File
16.2.2.1 “mv” Command – Rename File
To change the name of a directory or file in Shell, you can use the following command.