Synchronize Shared Memory Access with Semaphores

Implement synchronized shared memory with semaphores.

Requirements:

• Create shared memory segment
• Create semaphore set with semget()
• Initialize semaphore(s) with semctl()
• Use semop() for wait/signal operations
• Protect critical section with mutex semaphore
• Writer: wait(mutex), write, signal(mutex)
• Reader: wait(mutex), read, signal(mutex)
• Clean up semaphores and shared memory

Test:

• Multiple writers update shared counter
• Semaphores prevent race conditions
• Show proper synchronization
• Demonstrate data consistency