Operating Systems - Quiz(Unit 1) Batch-III

Consider the following code fragment: if (fork() == 0) { a = a + 5; printf("%d, %d \n", a, &a); } else { a = a - 5; printf ("%d, %d \n", a, &a); } Let u,v be the values printed by the parent process, and x,y be the values printed by the child process. Which one of the following is TRUE? a. u = x+10 , v = y b. u = x=10, v != y c. u+10 = x, v = y d. u+10 = x, v !=y

A CPU generally handles an interrupt by executing an interrupt service routine a. As soon as an interrupt is raised b. By checking the interrupt register at the end of fetch cycle. c. By checking the interrupt register after finishing the execution of the current instruction. d. By checking the interrupt register at fixed time intervals.

The following are some events that occur after a device controller issues an interrupt while process L is under execution. (P) The processor pushes the process status of L onto the control stack. (Q) The processor finishes the execution of the current instruction. (R) The processor executes the interrupt service routine. (S) The processor pops the process status of L from the control stack. (T) The processor loads the new PC value based on the interrupt. Which of the following is the correct order in the which the events above occur?

Select all the correct answer Which of the following standard C library functions will always invoke a system call when executed from single-threaded process in a UNIX / Linux system?

Which one or more of the following need to be saved on a context switch from one thread (T1) of a process to another thread(T2) of the same process? a) Page table base register b) Stack pointer c) Program counter d) General purpose registers

Which one or more of the following options guarantees that a computer system will transition from user mode to kernal mode? a) Function call b) Malloc call c) Page Fault d) System call