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difference between semaphores and mutex?

Answer Posted / selvakumar

"Mutexes are typically used to serialise access to a
section of re-entrant code that cannot be executed
concurrently by more than one thread. A mutex object only
allows one thread into a controlled section, forcing other
threads which attempt to gain access to that section to
wait until the first thread has exited from that section."

"A semaphore restricts the number of simultaneous users of
a shared resource up to a maximum number. Threads can
request access to the resource (decrementing the
semaphore), and can signal that they have finished using
the resource (incrementing the semaphore)."

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