Chapter 3 Study Cards

Question 1

Advanced Package Tools (APT)

Answer 1

A package management tool that’s most often used atop Debian packages, although a version for RPM also exists. APT enables package installation and updates from Internet repositories, including automatic dependency resolution.

Question 2

APT

Answer 2

A package management tool that’s most often used atop Debian packages, although a version for RPM also exists. APT enables package installation and updates from Internet repositories, including automatic dependency resolution.

Question 3

APT suite

Answer 3

The APT suite of tools includes a program, apt-cache, that’s intended solely to provide information about the Debian package database (known in Debian terminology as the package cache).

Question 4

Berkeley Internet Name Domain (BIND)

Answer 4

A common Domain Name System (DNS) server for Linux.

Question 5

BIND

Answer 5

A common Domain Name System (DNS) server for Linux.

Question 6

Build number

Answer 6

A number identifying minor changes made to a binary package by its maintainer rather than changes implemented by the program’s author, which are reflected in the version number.

Question 7

Checksum

Answer 7

A simple file integrity check in which the values of individual bits or bytes are summed up and compared to a stored value for a reference version of the file.

Question 8

Debian package

Answer 8

A package file format that originated with the Debian distribution but is now used on several other distributions. Debian packages feature excellent dependency tracking and easy installation and removal procedures.

Question 9

Dependency

Answer 9

A requirement of one software package that another one be installed. For instance, most Linux programs include a dependency on the C library.

Question 10

Dynamic library

Answer 10

A type of library that’s stored as a separate file from an executable program but that’s loaded along with the main program file. Dynamic libraries save disk space and RAM compared to static libraries.

Question 11

General Public License (GPL)

Answer 11

A common free software license, created and favored by the Free Software Foundation.

Question 12

glibc

Answer 12

A specific type of C library used on Linux systems since the late 1990s.

Question 13

GNOME

Answer 13

A common desktop environment for Linux, headquartered at http://www.gnome.org.

Question 14

GNU C library (glibc)

Answer 14

A specific type of C library used on Linux systems since the late 1990s.

Question 15

GNU Network Object Model Environment (GNOME)

Answer 15

A common desktop environment for Linux, headquartered at http://www.gnome.org.

Question 16

GNU’s Not Unix (GNU)

Answer 16

A project sponsored by the Free Software Foundation to create a free implementation of Unix. Linux relies heavily on GNU software-so much so that some people prefer the term GNU/Linux to Linux.

Question 17

GPL

Answer 17

A common free software license, created and favored by the Free Software Foundation.

Question 18

Hung

Answer 18

Term used to describe a program that’s stopped responding to user input, network requests, or other types of input to which it should respond. Hung processes sometimes consume a great deal of CPU time.

Question 19

jobs

Answer 19

The jobs command displays minimal information about the processes associated with the current session.

Question 20

K Desktop Environment (KDE)

Answer 20

A common desktop environment for Linux, headquartered at http://www.kde.org.

Question 21

KDE

Answer 21

A common desktop environment for Linux, headquartered at http://www.kde.org.

Question 22

kernel

Answer 22

The core of an operating system, which provides multitasking (process creation, interprocess protection, interprocess communication), memory management, and basic I/O management.

Question 23

kill

Answer 23

The kill command is the tool to terminate a process. This program sends a signal (a method that Linux uses to communicate with processes) to a process. The signal is usually sent by the kernel, the user, or the program itself to terminate the process.

Question 24

libc

Answer 24

A library of standard functions that can be used by all C programs.

Question 25

Library

Answer 25

A collection of code that's potentially useful to many programs. This code is stored in special files to save disk space and RAM when running programs that use the library.

Question 26

Load average

Answer 26

A measure of the demand for CPU time by running programs. A load average of 0 means no demand for CPU time; 1 represents a single program placing constant demand on the CPU; and values higher than 1 represent multiple programs competing for CPU time. (On multi-core CPUs, the load average can equal the number of cores before CPU-time competition begins.) The top and uptime commands both provide load average information.

Question 27

Logical block addressing (LBA)

Answer 27

A method of accessing data on a disk that uses a single sector number to retrieve data from that sector. LBA contrasts with cylinder/head/sector (CHS) addressing. Some sources refer to LBA as linear block addressing.

Question 28

Package

Answer 28

A collection of files stored in a single carrier file, ready for installation using a package management system such as RPM or the Debian package system.

Question 29

Path

Answer 29

A colon-delimited list of directories in which program files may be found. (Similar lists define the locations of libraries, fonts, and other file types.)

Question 30

Process

Answer 30

A piece of code that's maintained and run by the Linux kernel separately from other pieces of code. Most processes correspond to programs that are running. One program can be run multiple times, resulting in several processes.

Question 31

Release number

Answer 31

A number identifying minor changes made to a binary package by its maintainer rather than changes implemented by the program's author, which are reflected in the version number.

Question 32

Root Directory

Answer 32

The directory that forms the base of a Linux filesystem (meaning 2). All other directories are accessible from the root directory, either directly or via intermediate directories.

Question 33

RPM

Answer 33

The most popular package manager in the Linux world is the RPM Package Manager (RPM). RPM is also available on non-Linux platforms, although it sees less use outside the Linux world.

Question 34

Samba

Answer 34

The standard Windows interoperability suite of programs for Linux and Unix.

Question 35

Shared library

Answer 35

A type of library that's stored as a separate file from an executable program but that's loaded along with the main program file. Dynamic libraries save disk space and RAM compared to static libraries.

Question 36

Signal

Answer 36

In reference to processes, a code that the kernel uses to control the termination of the process or to tell it to perform some task. Signals can be used to kill processes.

Question 37

Source code

Answer 37

The version of a program written by a human and typically stored in plaintext (ASCII) file format. A compiler converts source code to a binary form that a computer can run.

Question 38

Tarball

Answer 38

A package file format based on the tar utility. Tarballs are easy to create and are readable on any version of Linux and on most non-Linux systems. They contain no dependency information, and the files they contain aren't easy to remove once installed.

Question 39

Yum

Answer 39

Yum is one of several meta-packagers, it enables you to easily install a package and all its dependencies using a single command line.