Mutual exclusion :

Question

Can Mutual exclusion can be enforced with a general semaphore initial value is greater than 1 ?

I think yes. Consider a semaphore $S = 2$, and following code segment for both processes.

P(S);
P(S);
<Critical Section>
V(S);
V(S);

Comments

yes here ME satisfied

But is it satisfied for each case? Say S=2 and there are 2 processes. Is here ME satisfied?

P(S);                              P(S)
<Critical Section>                 <Critical Section>
V(S);                              V(S)

No , because here we can start both process same time.

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if the statement says " Can Mutual exclusion can be enforced with a general semaphore initial value is greater than 1" (not can here). then answer should be yes.

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@srestha See this question

Answer 1

Yes Mutual exclusion is guaranteed with s=2.

But this solution also lead to DeadLock.

Comments

Well, I think circular wait is necessary condition for deadlock

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@Kapilp see this

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@hiteshp , yes, Circular wait is necessary condition for deadlock but not sufficient.

https://en.wikipedia.org/wiki/Deadlock#Necessary_conditions