A fast-food restaurant has four kinds of employees: (1) order takers, who take customers' orders; (2) cooks, who prepare the food; (3) packaging specialists, who stuff the food into bags; and (4) cashiers, who give the bags to customers and take their money. each employee can be regarded as a communicating sequential process. what form of interprocess communication do they use? relate this model to processes in unix.

Both direct communication(send(P,message),receive(id,message)) and indiect communication(send(A,message),receive(A,message)) can be used in the interprocess communication. Related UNIX processes(system calls):

simplest communication: using pipes

direct communication related system calls: msgget(), msgctl(),msgsnd() and msgrcv();

indirect commnunication related system calls: shmget();shmat();shmdt();shmctl();

Semorphore related: semget();semctl();semop()

Explanation:

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