inter/docs/PROJECT.md

Inter-process communication between two processes

System overview

Process	Description
init	Forks 4 child processes, reads data from them, and writes that data to the shared memory
P1-P4	Generates random priority number (in the range 0-19) and sends that priority number to the parent
scheduler	Creates the shared memory segment, reads data written into it, and prints that data

Implementation criteria

Criteria 1:

• Init is a parent process, which forks child processes P1-P4 (fork syscall)
• P1-P4: Process should generate a random integer between 0-19 (random number generation or simply hardcoded)
• P1-P4 should send the random integer to init through message passing (pipe syscall)
• Init should read data sent by P1-P4

Criteria 2:

• Scheduler is an independent process: it should create a shared memory segment (shmget and related syscalls)
• Scheduler should read data (a list of random numbers) written by init, sort the list in ascending order, and print the list (sorting algorithm of choice)

Criteria 3:

• Init should attach to the shared memory created by the scheduler process (shmat and related syscalls, hardcoded to any unique key of choice -> ftok syscall is a clean way to accomplish this)
• Init should write random numbers from P1-P4 into the shared memory

Termination:

• After scheduler prints the data, init should detach from shared memory and scheduler should detach and delete the shared memory segment (schmdt and shmctl syscalls)