Who can share?

What this operating-systems memory-sharing question tests

This is a medium-difficulty operating-systems question that probes your understanding of process isolation and the memory model. It asks you to distinguish between the different segments of a process's address space and reason about which ones the kernel permits to be shared across process boundaries.

To answer correctly, you need to be familiar with how modern operating systems partition virtual memory—the stack, heap, data segment, and text segment—and the access controls and mechanisms the kernel uses to enforce isolation by default. The question rewards precise language about which segments are inherently read-only versus writable, and under what conditions sharing is both safe and practical.

• Virtual address space layout and segment organization
• Process isolation and address-space independence
• Read-only versus read-write memory regions
• Shared libraries and memory-mapped files