philosophers @ 42

GOALS

• Learn how to make threads
• How to work on the same memory space
• Notions : mutex, semaphore and shared memory

TECHNICAL

• Options for ./exec : number_of_philosophers, time_to_die, time_to_eat, time_to_sleep, [nbr_philo_must_eat]
• number_of_philosophers : is the number of philosophers and also the number of forks
• time_to_die: is in milliseconds, if a philosopher doesn’t start eating ’time_to_die’ milliseconds after starting his last meal or the beginning of the simulation, it dies
• time_to_eat: is in milliseconds and is the time it takes for a philosopher to eat. During that time he will need to keep the two forks.
• time_to_sleep: is in milliseconds and is the time the philosopher will spend sleeping.
• nbr_philo_must_eat: argument is optional, if all philosophers eat at least ’nbr_philo_must_eat’ the simulation will stop. If not specified, the simulation will stop only at the death of a philosopher.

CODE

• Each philosopher should be given a number from 1 to ’number_of_philosophers’.
• Philosopher number 1 is next to philosopher number ’number_of_philosophers’. Any other philosopher with number N is seated between philosopher N - 1 and philosopher N + 1
• Any change of status of a philosopher must be written as follows (with X replaced with the philosopher number and timestamp_in_ms the current timestamp in milliseconds)
  • timestamp_in_ms X has taken a fork ◦ timestamp_in_ms X is eating
  • timestamp_in_ms X is sleeping
  • timestamp_in_ms X is thinking
  • timestamp_in_ms X died
• The status printed should not be scrambled or intertwined with another philosopher’s status.
• You can’t have more than 10 ms between the death of a philosopher and when it will print its death.
• Again, philosophers should avoid to die!