quiz 1-5 review

Question 1

pwd

Answer 1

print working directory

Question 2

ssh

Answer 2

connect to remote machine

Question 3

make

Answer 3

invoke Makefile to compile program

Question 4

gcc

Answer 4

compile program such as C program

Question 5

tar

Answer 5

work with .tar archive files or directories

Question 6

grep

Answer 6

search for text in files

Question 7

cp

Answer 7

copy file/directory

Question 8

history

Answer 8

show list of most recently entered commands

Question 9

top

Answer 9

display table of processes (i.e. programs) being run by users of computer

Question 10

touch

Answer 10

create blank file if it doesn’t exist else update its modification timestamp to present time

Question 11

wget

Answer 11

download file from internet

Question 12

mkdir

Answer 12

make empty directory

Question 13

mv

Answer 13

move or rename files

Question 14

ls

Answer 14

list directory contents

Question 15

hostname

Answer 15

show name of computer

Question 16

diff

Answer 16

compare two files line by line (assuming they are text files)

Question 17

scp

Answer 17

copy files, usually btwn two computers

Question 18

cd

Answer 18

change working directory

Question 19

argv[0]

Answer 19

./executable_name

Question 20

break

Answer 20

exit closest outside loop or exit switch statement

Question 21

continue

Answer 21

skip to next iteration of outside loop

Question 22

static

Answer 22

variable initialized once and retains its value across multiple function calls

Question 23

stack buffer overflow

Answer 23

trying to access array element at too high of an index

Question 24

stack buffer underflow

Answer 24

trying to access array element at too low of an index

Question 25

address sanitizer

Answer 25

expose runtime memory errors

Question 26

passed parameters

Answer 26

receive values, no access to where the values are stored <-> can’t change variables’ values outside function

Question 27

stack

Answer 27

variable’s size known at compile time, memory automatically allocated in function stack & de-allocated after function leaves stack

Question 28

heap

Answer 28

malloc/calloc memory for variables, must be freed else memory leak

Question 29

heap buffer overflow

Answer 29

not enough memory m/calloc’d to store data type or index too high

Question 30

free

Answer 30

only on m/calloc-ed memory

Question 31

double free

Answer 31

address sanitizer

Question 32

signed MSB 1

Answer 32

-2^(num of bits-1)

Question 33

signed and unsigned addition overflow

Answer 33

wrap around to smallest number

Question 34

octal literal prefix

Answer 34

0

Answer 35

XOR

Question 36

> > n

Answer 36

divide by 2^n

Question 37

«2

Answer 37

mult by 2^n, may overflow/sign change