Simple

Question 1

install command?

Answer 1

install [OPTION]… [-T] SOURCE DEST
install [OPTION]… SOURCE… DIRECTORY
install [OPTION]… -t DIRECTORY SOURCE…
install [OPTION]… -d DIRECTORY…

-copies files like cp
-can overwrite existing files
-creates destination directory if it does not exist
-can set permission tags
-sets files owners
-can remove non-essential baggage

Question 2

history command?

Answer 2

history
-displays without options since the start of the terminal session

history 5
-displays the last 5 commands

Question 3

What is Bash?

Answer 3

command language interpreter for the GNU operating system. “Bourne-Again SHell”, pun on Stephen Bourne, author of sh.

Question 4

What is a shell?

Answer 4

macro processor that executes commands.
-macro as in text and symbols are expanded to create larger expressions.

Question 5

Bios

Answer 5

First software that runs. identifies computer hardware, configures it, tests it, and connects it to the OS for further instructions (boot process).

Question 6

Boot Loader

Answer 6

Provides UI for user to load OS and applications.

brings system to a state in which it can perform its main function.

onboard bootloader resides in in an area of ROM or flash memory that is protected from getting written over.

Question 7

RAM

Answer 7

Random Access Memory. Volatile type storage. all data in RAM is deleted when device is turned off.

requires power to store data.

stores data for current instruction processing.

1-256GB data storage.

Question 8

ROM

Answer 8

Read only memory. can only read data. non-volatile (permanent memory).

does not require power to store data.

stores data to start or bootstrap a computer

4-8MB data storage

Question 9

CPU

Answer 9

Central Processing Unit. Accesses RAM and ROM. Instructions stored in RAM, and understands how to respond to RAM instructions from ROM.

Question 10

Binary / Octal / Hexadecimal

Answer 10

root2, root8, and root16 number systems.
10/2 = 5R0
5/2 = 2R1
2/2 = 1R0
1/2 = 0R1
10 in binary is 1010

21/16= 1.3125 //0.3125*16=5
1/16 = 0R1
21 in hex is 15

Question 11

Kernel

Answer 11

Core program that does all of the talking between the hardware and the software.

UI sends request to appropriate kernel, kernel sends request to CPU.

Kernel manages CPU, GPU, Memory, I/O devices, resource management, memory management, device management, system calls.

Kernel protects hardware.
Monolithic Kernel: OS and Kernel run in the same memory space. poor secuity.

microkernel: stripped down monoliithic kernel, prone to crashing systems.

hybrid: most commonly seen kernel,moves out drivers but keeps system services inside the kernel.

nano kernel: majority of its functions are set up outside the kernel,

exo-kernel: has process protection and resource handling, used for in-house testing and upgraded kernel types.

Question 12

System Call

Answer 12

Is a transition or communication from user space to kernel space. ‘syscall’ examples include Open, Read, Write, Close, Wait, Exec, Fork, Exit and Kill.

Question 13

Bits vs Bytes

Answer 13

both are units of data. one byte is 8 bits.

Question 14

Bash Command: man

Answer 14

used to display the user manual of any command that we can run on the terminal

man sleep

Question 15

Bash Command: cat

Answer 15

cat [option] [file]

cat > myfile.txt
adds the next input as text into myfile.txt

cat myfile.txt
displays content of myfile.txt to terminal

cat myfile.txt»myfile1.txt
copies myfile.txt to end of myfile1.txt

cat –n myfile1.txt
displays content but with line numbers

Question 16

Bash command: echo

Answer 16

in a bash, will ‘state’ or print to console

Question 17

Bash Command: who

Answer 17

who // pulls system and login info from /var/run/utmp. pass a different file path for a different file path

who -b // prints time of last system boot
who -d // lists all dead processes
who -r // outputs current run level
who -q / who –count //user names and curently logged in users.
who -a / who –all // prints all informations

Question 18

Bash Command: whoami

Answer 18

displays currently logged in user. can confirm succesful account change.

sudo whoami // checks if you have sudo privellages.

Question 19

Bash Command: sleep

Answer 19

sleep .8

will sleep .8 seconds

Question 20

Bash Command: ifconfig

Answer 20

interface configuration. used at boot time to set up interfaces as necessary. after that, used for debugging and system tuning.
ifconfig interface up/down //de/activates interface’s driver

https://www.geeksforgeeks.org/ifconfig-command-in-linux-with-examples/

can be used to de/activate interface drivers, ARP protocols, IPv6, and more

Question 21

Bash Command: sudo

Answer 21

grants admin access, or admin right to current command

Question 22

Bash command: alias

Answer 22

alias ll =”ls -la”

only available during current session

Question 23

Bash Command: ls

Answer 23

lists directories

ls -l
lists content of current directory

Question 24

Bash Command: cp

Answer 24

cp grades.txt documents
copies grades.txt to documents folder

Question 25

Bash Command: mv

Answer 25

movies files and folders
mv source -f target //forces an overwrite
mv source -i target //prompts confirmation before overwriting

Question 26

Bash Command: mkdir

Answer 26

creates new folder/directory
mkdir cat_files

Question 27

Bash Command: touch (edited)

Answer 27

touch myfile.txt

creates myfile.txt in current directory.

Question 28

Explain the difference between the numeric literals 5 and 5.0

Answer 28

Integer VS floating point type

Question 29

What is the difference between the if-else statement and the conditional expression?

Answer 29

one is a single programming statement, the other is a programming block with statements.

Conditional operator can be used to assign a value to a variable, while the if-else statement cannot be used for assignment purposes.

Question 30

declare int function “IsRight” taking 3 floats “a, b, c” as variables

Answer 30

static int IsRight(float a, float b, float c);

Question 31

Conditional Expression. if a is greater than b, assign 1 to c. else assign 0.

Answer 31

c = (a>b) ? 1 : 0;

Question 32

for(i=0 ; i<10 ; i++)

when does the initialization expression run?
test expression?
update expression?

Answer 32

excutes once, before the first iteration,
tests before every iteration. terminates loop if false.
executes after every iteration. will not run if test was false.

Question 33

Bash Command: Bash