Linux Essentials 010 160

______________ __ preserve the literal value of *most characters* contained within the quotes, exceptions include *$* (for variables), *'*(for single characters) and *\*(for escaping a character)

"" Double quotes

when dealing with regular expressions, if I wanted to match the end of a line i would add a $

$ example // Apple$

You're unable to exit the vi editor without saving the changes made to the file by using the :q command. Why?

! is not appended with the command. The :q command only exits the file if the changes are saved.

piping allows what?

The user to feed in the results of one command into another command.

using man -k is the same as using

apropos "KEYWORD"

tar f

file name type of archive file

| (pipe) command in Regular expressions does what?

logical OR between two patterns

a user wants to view hidden files in a directory

ls -a

a user wants to display file information in a human readable format

ls -h

a user wishes to see a long listing view of files and their permissions

ls -l

a user wishes to see a listing of size of their files

ls -s

zip and name a file trip.zip with max compression

zip -9 trip.zip arbitrary_file.txt

If i wanted to alphabetize the results of cat apple_results.txt what would succeed the file name?

| sort pipe sort command

bash operator OR

||

what is the result of utilizing a question mark (?) in the cmd line?

Matches up exactly one character

what is "read" in bash scripting

same as cin in c++ takes input from keyboard

what is found in the etc/resolv.conf

search nameserver domain

How can you browse to a new node using the standard info documentation reader?

select hyperlink with arrow keys and enter button for selection

which sort option will you use to specify a target file?

sort -o

tar t

t- view content of archive file

to determine the number of files and folders?

wc -l (wordcount -lines)

what does the ./ denote in a command or script

we can run it from here the current directory

which CPU types does Linux run?

x86 ARM x64

__________ is used to preserve the literal value of *every character* contained within the quotes, including the escape character

' ' Single quote

tar j

--xz

If i wanted to redirect the output of the cat and grep commands, what would succeed the pattern Apple? cat american-english | grep Apple

> apple_results.txt

If i wanted to redirect and append the output of the cat and grep commands, what would succeed the pattern Apple? cat american-english | grep Apple

>> apple_results.txt

memory leaks lead to what?

A program keep requesting for more memory a program failing to return memory after it is done with it

three command modes in vi

Ex Command Insert

Which of the following statements are true of functions in Linux scripts?

Fn's can be declared by using the fn keyword A fn is called by its name in a script similar to an ordinary command

cut command does what

Prints selected parts of lines from each file to output

cut -d

Prints selected parts of lines then delimits (cuts) a portion of text with some character

observe cat american-english | grep -E "Ap*le" What does the "Ap*le" expression mean?

That there will be 0 or more Ps in the phrase "Ap*le"

observe cat american-english | grep -E "Ap+le" What does the "Ap+le" expression mean

That there will be 1 or more P s in the phrase "Ap+le"

observe grep -E What does the option -E denote?

The allowing of regular expressions

Only root may change a file's ownership with chown.

True

grep -E, allows what?

Use of regular expressions in the grep command

id command displays?

Username Group memberships UID

chmod o+t subdir

You want to set the sticky bit on an existing directory, subdir, without otherwise altering its permissions

a non quoted _______ is the ______ and preserves the *literal value of the next following character * with the single exception of newline "n"

\ Escape Character

userdel -f

deletes a user that is currently logged on

which command deletes a group in linux

delgroup

A user enters the etc/passwd file and wishes to output the string :/home/michael. the entire strings reads michael:x:1000:1000:michael christian...:/home/michael:/bin/bash what series of piped commands must he enter to output this string

cat etc/passwd | grep michael | cut -d: -f6

command to change a files group

chgrp chown

What command would you type (as root) to change the ownership of somefile.txt from ralph to tony?

chown tony somefile.txt

tar z

compressed gzip archive

useradd -r

creates a system account (has no directory)

tar c

creates an archive file

chmod +x does what to a script

gives user, group, other executable writes

grep command for displaying number of matching lines in a file

grep -c

input redirection example

grep Apple < sorted.txt

output redirection example

grep Apple > sorted.txt

Which of the following commands is used to view a list of most recent commands executed by a user?

history

a user wants to display the list of all the users logged in and out since the file /var/log/wtmp was created

last

you want to narrow a search in man for keywords

man -k "KEYWORD"

what is the result of uytilizing an Asterisk (*) in the cmd line?

match any number of character(s)

A user must utilize "Globbing". What is globbing?

methods used to match patterns in filenames or text by using a wildcard character to create a pattern.

sets the number of pings sent in linux

ping -c

grep -E ^M american-english

prints out words starting with M in the file american-english

tar command what does rf mean and do

r - append f - file name

userdel -r

removes a users home directory AND deletes the account

tar x

to untar or extract use, the x

a user wants a list of running processes, what command should she use

top- shows tasks ps- shows processes

what is used to set default file permissions for newly created files

umask

A user wants to check what kernel release he has, what cmd should he use

uname -r

A user wants to check what kernel name he has, what cmd should he use

uname -s

A user wants to check what version his kernel is running on, what cmd should he use

uname -v

what is the | pipe used for?

used for applying more than one condition

what is the ($) used for?

used to match ending character

what is the {} curly brace used for?

used to match more than one pattern

what is the caret (^) used for?

used to match starting character

tar v

verbosely state .tar file progress

a user wants to check all the current users logged on to a Linux machine what cmd should they use?

w

to count the number of words

wc