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You are required to write a C program to solve the following synchronization problem using POSIX and “semaphore.h” libraries. N mCounter threads count independent incoming messages in a system and another thread mMonitor gets the count of threads at time intervals of size t1, and then resets the counter to 0. The mMonitor then places this value in a buffer of size b, and a mCollector thread reads the values from the buffer. Any thread will have to wait if the counter is being locked by any other thread. Also, the mMonitor and mCollector threads will not be able to access the buffer at the same time or to add another entry if the buffer is full. Assume that the messages come randomly to the system, this can be realized if the mCounter threads sleep for random times, and their activation (sleep time ends) corresponds to an email arrival. Similarly, the mMonitor and mCollector will be activated at random time intervals.Breaking the problem down overview The problem statement may seem a little bit intimidating but once you divide the problem into smaller sub-problems; It'll become easier to approach. We have 3 types of threads mCounter , Monitor , and mCollector . At our main function, we should create one mMonitor thread, one mCollector thread but N mCounter threads. You should define N as a constant at the beginning of your code with any number you like 💡 5 to 10 threads are sufficient but you may decide to go higher or lower than that to test your code As mentioned above, to simulate messages coming randomly to the system we can let each mCounter thread sleep for a random period of time before it starts. Also, both the mCollector and mMonitor thread should be activated at random time intervals.Check srandom , random , and sleep . Dividing the problem It becomes much easier if we divided up the problem into two sub-problems Problem 1 Threads included: The N mCounter threads. The mMonitor thread. Shared resources: An integer to count messages. Problem: When a mCounter thread grants access to the counter, it should add one to it. When the mMonitor thread grants access to the counter, it should reset it to 0 and save its value to use it later. Only one thread should be able to access the shared counter.Problem 2 Threads included: The mMonitor thread. The mCollector thread. Shared resources: A buffer that should be implemented using a FIFO queue. Problem: It’s a bounded buffer producer/consumer problem. mMonitor is the producer. It enqueues the value that was saved from the previous problem into the buffer. mCollector is the consumer it takes the data out of the buffer.Program output The output shows the behavior of the threads. Each thread should print a certain output when a particular event happens: mCounter : At time of activation (sleep time end): Counter thread %I%: received a message Before waiting: Counter thread %I%: waiting to write After increasing the counter: Counter thread %I%: now adding to counter, counter value=%COUNTER% mMonitor : Before waiting to read the counter: Monitor thread: waiting to read counter After reading the counter value: Monitor thread: reading a count value of %COUNTER% After writing in the buffer: Monitor thread: writing to buffer at position %INDEX% If the buffer is full: Monitor thread: Buffer full!! mCollector : After reading from the buffer: Collector thread: reading from the buffer at position %INDEX% If the buffer is empty: Collector thread: nothing is in the buffer!
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