Operating System Architecture Set 4 MCQs

Q1 | what is use of ls command ?

to list names and attribute of files

to list size of files

to list length of files

none of these

Q2 | Access permission can be set to …………

the file owner

a file group

everyone else

all of these

Q3 | The Newly created files are ………….. of the file system directory structure.

main nodes

root nodes

leaf nodes

middle nodes

Q4 | Unix system treats devices as a ……..

hardware

file

byte

none of these

Q5 | Permission mode on newly created file will be……

0666(octal)

0666(hexadecimal)

0999(octal)

0798(hex)

Q6 | Permission mode 0666(octal) means…………

allowing all users acess to file for writing

allowing all users acess to file for reading

restrict to read and write

allowing all users access to file for reading writing

Q7 | All system calls return ……..if open or create call fails

-2

0

1

-1

Q8 | The open and create system calls returns an integer called a ……….

file number

file discriptor

file variable

none of these

Q9 | File discriptor programs uses………………...

to delete file

to save file

for subsequent references for file

none of these

Q10 | The read system calls return 0 when………..

it reaches middle of file

it reaches end of the file

file is empty

none of these

Q11 | When a process makes a system call ,its mode changes from………

user to kernel

kernel to user

restricted to unrestricted

unrestricted to restricted

Q12 | The new process called, child process gets a ………... return value from fork.

-1

0

2

1

Q13 | The child process invoke …….to execute program copy .

fork

execl

wait

printf

Q14 | Which of the following system calls transforms an executable binary file into a process?

fork

exec

ioct1

longjmp

Q15 | Which of the following file names can be found in more than one directory?

passwd

bin

date

none of the above

Q16 | The command that can be used to restrict incoming messages to a user is………..

mesg

halt

grep

sleep

Q17 | The sort command in UNIX ….

used to sort a file

used to sort the list of files in a directory

both a and b

none of the above

Q18 | Which command is used to remove a directory?

rd

rmdir

dldir

rdir

Q19 | The tail command in UNIX……

can be used to look at the tail or bottom of the file

can be used to display the list of last 10 files in the current directory

can be used to display the list of last 15 in the current directory

none of the above

Q20 | Which command is used to remove a file……

rename

mv

rm

del

Q21 | Which command will be used with vi editor to append text at end of line?

a

i

a

l

Q22 | Which of the following command the file names in multiple columns?

is–x

is

is–1

is–f–x

Q23 | Which command is used to display the device name of the terminal you are using?

who

ls

tty

stty

Q24 | Which command allows you to view your file 24 lines at a time ?

more

cat

pg

none of the above

Q25 | Which of the following is not a communication command?

write

mail

mesg

grep