代码与程序的区别与联系

//第一段程序：fork与多进程

#include <unistd.h>
#include <stdio.h>
int main ()
{
pid_t fpid=fork();
if (fpid < 0) printf("error in fork!");
else if (fpid == 0) printf("i am the child process, my process id is %d/n",getpid());
else printf("i am the parent process, my process id is %d/n",getpid());
return 0;
}

//第二段程序：sleep（wait）与多线程

public class ThreadTest implements Runnable {

int number = 10;

public void firstMethod() throws Exception {
synchronized (this) {
number += 100;
System.out.println(number);
}
}

public void secondMethod() throws Exception {
synchronized (this) {
Thread.sleep(2000);//1.sleep的是哪个线程？ 2.如果把本行换成下一行的语句，程序执行会有什么不同？
//this.wait(2000);
number *= 200;
}
}

@Override
public void run() {
try {
firstMethod();
} catch (Exception e) {
e.printStackTrace();
}
}

public static void main(String[] args) throws Exception {
ThreadTest threadTest = new ThreadTest();
Thread thread = new Thread(threadTest);
thread.start();
threadTest.secondMethod();
}
}

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