Assignment name: process_termination
Expected files: process_termination.c
Allowed functions: memset, printf, malloc, free, write, fork, kill, exit, waitpid,
                    sem_open, sem_close, sem_post, sem_wait, sem_unlink,
                    usleep, gettimeofday
-------------------------------------------------------------------------------

Create a program that demonstrates process termination and cleanup:
1. Launch 5 child processes that run in a loop (each iteration takes 500ms)
2. Each child has a random "death time" between 2-5 seconds
3. Parent process monitors all children using waitpid() with WNOHANG
4. When a child "dies" (exits), parent detects it and kills all remaining children using kill()
5. Parent prints which child died first and performs cleanup

Output format:
- "Child <id> (PID: <pid>): Iteration <n>"
- "Child <id> (PID: <pid>): Dying after <time>ms"
- "Parent: Child <id> (PID: <pid>) has died!"
- "Parent: Terminating remaining children..."
- "Parent: Child <id> (PID: <pid>) terminated"
- "Parent: All processes cleaned up"

Usage: `./process_termination`

Hint: This simulates what happens in philosophers_bonus when one philosopher dies.
Use waitpid() with WNOHANG to check if a child has exited without blocking.
kill(pid, SIGTERM) or kill(pid, SIGKILL) terminates a process.
Proper cleanup is critical - all child processes must be terminated.
This is why philosophers_bonus needs a monitoring mechanism in the parent.