mitS6.081 lab记录

lab1 : Xv6 and Unix utilities

环境配置

//step1 
$ git clone git://g.csail.mit.edu/xv6-labs-2021
//step2
$ cd xv6-labs-2021
$ git checkout util

lab 1

sleep

// 新建user/sleep.c
#include "types.h"
#include "user.h"

int main(int argc, char *argv[])
{
    // 检查参数是否正确
  if(argc != 2){
    fprintf(2, "usage: sleep n\n");
    exit(1);
  }
  // 转换参数为整数
  int n = atoi(argv[1]);
  // 等待n秒
  sleep(n);
  exit(0);
}