System Admin Linux Ch 14 Quiz Review

What does the time command show? (Pick 3)

• The time something took to execute in real time

• The time spent in kernel mode

• The time spent in user mode

• The time spent in supervisor mode

Answer explanation

When creating a bash script, it is important to document the purpose of the script. Which of the following is the correct syntax for a comment?

• # comment

• ! comment

• // comment

• /* comment

Answer explanation

Comments begin with a hash tag (#). The shell ignores these lines when running the script. Comments help communicate how the script was constructed and what it is designed to do.

A​ (a)   allows a user to interact with the computer through stdin (the keyboard) and stdout (the display screen).

• shell
• syslog
• headset
• TTY

Answer explanation

A shell (also referred to as an interactive shell) allows a user to interact with the computer through stdin (keyboard) and stdout (display).

It can be run interactively or as a batch file.

Shells are the primary command line interface (CLI) for Linux systems.

An interactive shell that doesn't require the user to enter a user ID and password.

• Non-login shell

• .bat file

• cmd.exe

• SSL

Answer explanation

Non-login shells do not require a userid or password.

They should only be used for non-priviliged tasks.

A bash construct in the form of ${} that substitutes the variables value for the name of a variable.

• Variable expansion

• Command substitution

• Associative array

• Special parameters

Answer explanation

Variables allow you to store values for later use.

Variable expansion allows for the use of those variable values in other commands.

A(n) ​ (a)   is a bash variable that is inherited by child shells.​

• environment variable
• parameter
• constant
• positional array value

Answer explanation

Every Linux process is a ​ (a)   process and can have one or more ​ (b)   processes.

• parent
• child
• remote
• local
• active

Answer explanation

Every Linux process (executing code) is a child of the root process.

These processes are themselves parent processes to any process they spawn.

You can think of these processes as a tree, with each process being a branch (parent processes) that can fork off other branches (child processes).

​ (a)   are a series of special variables that contain the arguments given when the shell is invoked. The names of these special variables are digits, so they’re referenced by $1, $2, $3, $4, and so on.

• Positional parameters
• Array variables
• User names
• Script options

Answer explanation

​ (a)   are a list of parameters that can only be referenced using the dollar sign. Their values are set and maintained by the bash shell.

• Special parameters
• Shell parameters
• Environment variables
• Script variables

Answer explanation

In the bash shell, ​ (a)   are treated the same as environment variables and shell variables.

• user variables
• array values
• script parameters
• parent process parameters

Answer explanation