R4RIN – MCQs, Mock Tests | Unix/Lunux Linux Mcqs Questions Set 13

What is a context switch?

1. Kernel switches from executing one process to another
2. Process switches from kernel mode to user mode
3. Process switches from user mode to kernel mode
4. None of the mentioned

✅ Correct Answer: 1

Pid of init process

1. 0
2. 1
3. 32767
4. none of the mentioned

✅ Correct Answer: 2

What is the default maximum number of processes that can exist in Linux?

1. 32768
2. 1024
3. 4096
4. unlimited

✅ Correct Answer: 1

How do you get parent process identification number?

1. waitpid
2. getpid()
3. getppid()
4. parentid()

✅ Correct Answer: 3

Parent process id of a deamon process is

1. 2
2. 3
3. 4
4. 1

✅ Correct Answer: 4

The process which terminates before the parent process exits becomes

1. Zombie
2. Orphan
3. Child
4. None of the mentioned

✅ Correct Answer: 1

Return value of fork() system call can be:

1. -1,<0, 0
2. -1,>0, 0
3. -1,<0
4. none of the mentioned

✅ Correct Answer: 2

If the fork() system call returns -1, then it means?

1. No new child process is created
2. The child process is an orphan
3. The child process is in Zombie
4. none of the mentioned

✅ Correct Answer: 1

Fork returns _____ to parent process on success

1. 0
2. child process id
3. parent process id
4. none

✅ Correct Answer: 2

On x86-32 Linux, at which address the code segment of the program starts?

1. 0x00000000
2. 0x08048000
3. 0x80000000
4. 0xbfff0000

✅ Correct Answer: 2

On x86-32 Linux, at which address the user stack resides normally?

1. 0x00000000
2. 0x3fff0000
3. 0x7fff0000
4. 0xbfff0000

✅ Correct Answer: 4

A system has 512MB of physical memory. Which among the following is not a suitable virtual memory size for this system architecture?

1. 512MB
2. 256M
3. 4GB
4. None of the mentioned

✅ Correct Answer: 4

LRU stands for

1. Last received Unit
2. Least recently Used
3. Least recently usable
4. Lost Recoverd unit

✅ Correct Answer: 2

Mm_struct maintains?

1. memory files
2. open files
3. pipe
4. active memory regions

✅ Correct Answer: 4

Which sytem call can be used by a user process to lock a memory so that it cannot be swapped out?

1. memory files()
2. memlock()
3. pipe()
4. active memory regions

✅ Correct Answer: 2

Among these files which has an ELF format

1. shared objects
2. core
3. executables
4. all of the mentioned

✅ Correct Answer: 4

What is the use of strace command?

1. strace can be used to check the system calls called by the program. So, this can be used for debugging and benchmarking purposes
2. strace cannot be used to check the system calls called by the program
3. all of the mentioned
4. none of the mentioned

✅ Correct Answer: 1

If one of the thread in multithreaded process is blocked on an I/O, which of the following is true?

1. The entire process with block if their is no kernel supported threads
2. Other threads of the process will continue to execute even if there is no kernel supported threads
3. It depends on specific implementatation
4. All of the mentioned

✅ Correct Answer: 1

Which one can be a real time schedule policy?

1. SCHED_FIFO
2. SCHED_SPF
3. SCHED_OTHER
4. SCHED_FILO

✅ Correct Answer: 1

In Linux kernel-2.6 Real time priority ranges from

1. 0 to 99
2. 0 to 139
3. -20 to 19
4. 100 to 139

✅ Correct Answer: 1

Solaris real time class priority is

1. 0-59
2. 60-99
3. 100-159
4. 160-169

✅ Correct Answer: 3

Solaris System class priority is

1. 0-59
2. 60-99
3. 100-159
4. 160-169

✅ Correct Answer: 2

Each process has unique

1. fd table
2. file table
3. inode table
4. data block table

✅ Correct Answer: 1

File descriptor table indexes which kernel structure?

1. struct file
2. strruct fs_struct
3. files_struct
4. struct inode

✅ Correct Answer: 1

What is the default number of files open per user process?

1. 0
2. 1
3. 2
4. 3

✅ Correct Answer: 4

The file system information is stored in

1. Boot block
2. Super Block
3. Inode Table
4. Data Block

✅ Correct Answer: 2

Switch table is used by

1. device special file
2. directory file
3. fifo
4. link file

✅ Correct Answer: 1

What is the use of fcntl function?

1. locking a file
2. reading the file descriptor flag
3. changing the file status flag
4. all of the mentioned

✅ Correct Answer: 4

Which function can be used instead of the dup2 to duplicate the file descriptor?

1. read()
2. open()
3. stat()
4. fcntl()

✅ Correct Answer: 4

printf() uses which system call

1. open
2. read
3. write
4. close

✅ Correct Answer: 3

read() system call on success returns

1. 0
2. -1
3. number of character
4. none

✅ Correct Answer: 3

Which system call is used to create a hard link?

1. hardlink
2. link
3. symlink
4. ln

✅ Correct Answer: 2

namei() is

1. ANSI C library function
2. C library function
3. System call
4.

✅ Correct Answer: 4

dup2(1,0)

1. closes the stdout and copies the stdin descriptor to stdout
2. closes the stdin and copies the stdout descriptor to stdin
3. will produce compilation error
4. None of the mentioned

✅ Correct Answer: 2

If a signal is received by a process, when will it be processed?

1. It is processed immediately
2. It is processed when process is switching to kernel mode
3. It is processsed in the next timeslice given to the process
4. None of the mentioned

✅ Correct Answer: 2

Which signal is generated when we press control-C?

1. SIGINT
2. SIGTERM
3. SIGKILL
4. SIGSEGV

✅ Correct Answer: 1

Which signal is generated when we press ctrl-Z?

1. SIGKILL
2. SIGSTOP
3. SIGABRT
4. SIGINT

✅ Correct Answer: 2

Which signal is sent when the Child process terminates?

1. SIGINIT
2. SIGKILL
3. SIGSTOP
4. SIGCHLD

✅ Correct Answer: 4

Which of the following signal cannot be handled or ignored?

1. SIGINT
2. SIGCHLD
3. SIGKILL
4. SIGALRM

✅ Correct Answer: 3

Another signal that cannot be caught is:

1. SIGPIPE
2. SIGHUP
3. SIGSTOP
4. SIGUSR1

✅ Correct Answer: 3

When real interval timer expires which signal is generated?

1. SIGINT
2. SIGCHLD
3. SIGKILL
4. SIGALRM

✅ Correct Answer: 4

Signals are handled using which system call?

1. kill
2. signal
3. both
4. none

✅ Correct Answer: 2

Default action of SIGSEGV is

1. Terminate
2. Core dump + Terminate
3. Stop
4. Cont

✅ Correct Answer: 2

The kill system call is used to

1. Send shutdown messages to all by superuser
2. Send a signal to a process
3. Kill processes
4. Stop the processes

✅ Correct Answer: 2

Which is true regarding pipes?

1. half duplex
2. full duplex
3. message boundaries are preserved
4. unordered data

✅ Correct Answer: 1

The persistancy of a FIFO is

1. process
2. kernel
3. file system
4. none of the mentioned

✅ Correct Answer: 3

Advantage of FIFO over pipe is

1. related processes can communicate
2. unrelated processes can communicate
3. all of the mentioned
4. none of the mentioned

✅ Correct Answer: 2

What mkfifo() creats?

1. pipe
2. unnamed pipe
3. named pipe
4. msg queue

✅ Correct Answer: 3

System V IPC common attributes are

1. key
2. id
3. owner
4. all of the mentioned

✅ Correct Answer: 4

Which one of the following is not system V IPC ?

1. Shared Memory
2. Semaphores
3. FIFO
4. Message Queues

✅ Correct Answer: 3