Unix fork：创建了多少个进程？

Question

Hi I am doing exercises on Operating System Concepts 9th Edition Chapter 3, there is a "how many processes are created including the parent process?" question confusing me. The code is in C with Unix system call, fork():

#include <stdio.h>
#include <unistd.h>

int main(){

fork();
fork();
fork();

return 0;
}

How any buddy answer the question? Thanks

Answer 1

fork(); 

1st fork created new process from running process(main) . in System now there is two process

fork();

Each of Both process again calls fork. So two new process created. So total four process is in system now

fork();

Now Each four process calls fork. so again four new process created. so total eight process is created after last call of fork();

Answer 2

我猜它是8，像1 - > 2 - > 4 - > 8

Answer 3

There are total 8 process including parent process. Here,