OS Foundations Checkpoint

1. A system call is:

A controlled entry from user mode to kernel mode A hardware interrupt only A user-space library function A context switch

2. A zombie process is:

Exited but not yet reaped Blocked on I/O Running on the CPU A kernel thread

3. When a parent exits before a child, the child is:

Reparented to PID 1 Killed immediately Left with no parent Put in kernel mode

4. Fork creates:

A new process with duplicated state A new thread in the same address space A new file descriptor A context switch

5. True/False: PID 1 is typically treated specially and should not exit.

6. Context switches are expensive because they:

Save/restore registers and disrupt caches Allocate memory Always involve disk I/O Change the instruction set