Processes communicate through mechanisms such as pipes, sockets and shared memory. Serialization, synchronization and isolation differ.
Before you start
You should understand processes, threads, memory and basic file operations. Track ownership and state changes over time. For concurrent scenarios, write down at least two possible execution orders; the same instructions can behave differently when scheduling or resource availability changes.
The practical goal is to reason through this situation: A socket protocol makes ownership explicit; shared memory can reduce copying but requires coordination. Read the walkthrough first, then try the interview exercise before opening its answer. The important part is explaining the decision and its consequences, rather than remembering a definition alone.
Step-by-step walkthrough
Step 1: Choose the trust boundary
Processes may need controlled interfaces rather than unrestricted shared access.
Step 2: Estimate transfer costs
Sockets and pipes can involve copying or serialization.
Step 3: Design synchronization
Shared memory reduces some copying but requires explicit safe ownership.
Worked scenario
A socket protocol makes ownership explicit; shared memory can reduce copying but requires coordination.
Two processes exchange large image data. Shared memory may reduce copying, but they still need a protocol identifying which buffer is ready and when reuse is safe. A socket message boundary must also be defined where its transport is stream-based. Peak throughput alone does not decide the safer mechanism.
Common mistake
Shared memory alone does not define message framing or safe concurrent access.
Verify the behavior
Compare lifetime, framing, failure recovery and transfer costs for the actual payload.
Interview exercise
Choose an IPC mechanism.
Answer and reasoning
Compare payload size, trust boundary, lifetime and synchronization requirements rather than selecting only by peak speed.
Continue learning
Compare the scenario with the Operating Systems interview questions and test your understanding with the Operating Systems MCQs. For terminology and implementation details, consult the reference material.