What resources are shared between threads?
Recently, I have been asked a question in an interview what's the difference between a process and a thread. Really, I did not know the answer. I thought for a minute and gave a very weird answer.
Threads share the same memory, processes do not. After answering this, the interviewer gave me an evil smile and fired the following questions at me:
Q. Do you know the segments in which a program gets divided?
My answer: yep (thought it was an easy one) Stack, Data, Code, Heap
Q. So, tell me: which segments do threads share?
I could not answer this and ended up in saying all of them.
Please, can anybody present the correct and impressive answers for the difference between a process and a thread?
Answer
You're pretty much correct, but threads share all segments except the stack. Threads have independent call stacks, however the memory in other thread stacks is still accessible and in theory you could hold a pointer to memory in some other thread's local stack frame (though you probably should find a better place to put that memory!).