CET130 CHAP 7

What number represents the stdin file descriptor?

0

What number represents the stderr file descriptor?

2

What character is used to delimit most Linux configuration files?

:

In order to redirect a file to the standard input of a command, what metacharacter should be used?

<

The standard output and standard error from a terminal screen within the BASH shell can be redirected to a file on the filesystem using what shell metacharacter, followed by the absolute or relative pathname of the file?

>

Given the syntax command && command, the command on the left of the && construct is executed only if the command on the right of the && construct completed successfully.

False

The ________ environment variable contains a list of directories to search for executable programs.

PATH

Any command that can be executed on the command line can also be placed inside any environment file.

True

You are limited to using one pipe | metacharacter on the command line to pipe information from one command to another command.

True

Select the escape sequence that is used for a form feed:

\f

The ability to extract, manipulate, and format text using pattern action statements belongs to which command below?

awk

A list of all exported environment and user-defined variables in a shell can be viewed with what command below?

env

A case construct must be ended by __________.

esac

The ______ command takes user input from stdin and places it in a variable specified by an argument.

read

What permissions are required to execute a shell script in a manner similar to any other executable program on the system?

read and execute

The environment variables that are set by default and their current values can be viewed with what command?

set

The default BASH shell prompt is set by an environment variable. What command can be used to view this variable?

set command

Most commands that are run by the shell are run in a separate ________, which is created by the current shell.

subshell

What command can be used to replace characters in a file sent via Standard Input?

tr...

Which command can be used to count the number lines, words, and characters in a file?

wc

Select the metacharacter that can be used to send the standard output of one command to another command as standard input:

|

What character combination at the start of a shell script are referred to as a hashpling, and allow for the specification of the shell that interprets the contents of the script?

#!

What environment file is always executed immediately after login for all users on the system, and sets most environment variables, such as HOME and PATH?

/etc/profile

Select the escape sequence that starts a new line when used with echo:

/n

To prevent a file from being cleared by the BASH shell and append output to the existing output, you can specify three > metacharacters alongside the file descriptor.

True

You can use the sed command to remove unwanted lines of text.

True

Select the test statement that can be used to determine if A is numerically greater than B:

[ A -gt B ]

Any command that can take standard input and transform it into standard output is called a(n) ______command.

filter

What construct is intended for use in processing a list of objects, such as files, directories, users, printers, and so on?

for

What operator below is known as the NOT operator?

!