Computer Knowledge

Operating Systems

1,344 Questions

Test your computer knowledge with these questions on operating systems. The content covers various platforms including Unix, Linux, Windows, Android, and Macintosh. These questions are commonly asked in the computer knowledge sections of banking and government exams.

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Operating Systems Questions

Multiple choice

In which block is available free inode number found?

  1. Boot block

  2. Super block

  3. Inode block

  4. Data blocks
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The super block contains information about the entire disk and the I-node list -a list of inodes. The super block also contains an array to represent free inodes.

Multiple choice

A certain computation generates two arrays a and b such that a [i] = f (i) for 0 $\le$ i < n and b [i] = g (a [i]) for 0 $\le$ i < n. Suppose this computation is decomposed into two concurrent processes X and Y such that X computes the array a and Y computes the array b. The processes employ two binary semaphores R and S, both initialised to zero. The array a is shared by the two processes. The structures of the processes are shown below.

Process X; 
Process Y;
private i;
private i;
for (i = 0; i &lt; n; i + +) {                            
  for (i = 0; i &lt; n; i + +) {
         a [i] = f (i);
         EntryY (R, S);
         ExitX (R, S); 
         b [i] = g (a [i]);
    }
}

Which one of the following represents the CORRECT implementations of ExitX and EntryY?

 
  1. ExitX (R, S) {
   P (R) ;
   V (S) ;
}
EntryY (R, S) {
   P (S);
   V (R);
}

  2. ExitX(R, S) { 
  V (R); 
  V (S);
}
EntryY (R, S) {
  P (R);
  P (S);
}

  3. ExitX (R, S) {
  P (S);
  V (R);
}
EntryY (R, S) {
  V (S);
   P (R);
}

  4. ExitX (R, S) {
  V (R);
  P (S);
}
EntryY (R, S) {
  V (S);
  P (R);
}
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Process X produces a[i] and signals completion. Process Y consumes a[i] and must wait for X to produce it. ExitX signals completion by V(R) and V(S) (signal both semaphores). EntryY waits for X's signal by P(R) then P(S) (wait on both semaphores). This ensures Y only accesses a[i] after X has written it. Option B implements this correctly - V(R), V(S) in ExitX and P(R), P(S) in EntryY ensures proper synchronization.