Question

Which of the following are necessary conditions for a deadlock?

• A. Mutual Exclusion and Hold and Wait
• B. Preemption and Circular Wait
• C. Mutual Exclusion and No Preemption
• D. Hold and Wait and Preemption

Hint:

All four conditions must hold for a deadlock; preventing any one avoids it.

Answer 1

The Correct Option is A

Deadlock occurs when processes cannot proceed due to resource conflicts.
The four necessary conditions are:
1. Mutual Exclusion: Resources are held in a non-shareable mode.
2. Hold and Wait: Processes holding resources request additional ones.
3. No Preemption: Resources cannot be forcibly taken.
4. Circular Wait: Processes form a circular chain of resource requests.
Option (1) lists two correct conditions.
Option (3) is partially correct but incomplete.
Options (2) and (4) include incorrect conditions (preemption is not a deadlock condition).