counting semaphore related question

Question

A binary semaphore ensures mutual exclusion. Does a counting semaphore ensure mutual exclusion too?

Please justify your answers.

Comments

i think even binary semaphore cant ensure mutual exclusion wrong use of it can violate.

Answer 1

Yup improper use of semaphore not ensure the mutual exclusion . only proper use of semaphore ensure mutual exclusion. ex: monitor.

Comments

Please elaborate ...

Answer 2

Counting semaphore can be used to implement mutual exclusion by setting variable

'value' = 1    // value indicate number of processes allowed to enter CS

Comments

does binary semaphore always implies mutual exclusion ?

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as binary semaphore has values 0 and 1 , it always implies mutual exclusion

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"as binary semaphore has values 0 and 1 , it always implies mutual exclusion"

It's wrong conclusion, it depends on implementation, apply only up operation no down operation, n number of process can go in CS

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@Vijay agreed. Consider n binary semaphores initialized to 1 for n number of processes. Here @tiger implication goes incorrect.