text: #include "types.h"
  #include "user.h"
  #include "param.h"
  #include "fcmtl.h"
  
  int main(int argc, char** argv){
  	printf(1, "fork test\n");
  	int i, size = 8192;
  	int fd = open("README", O_RDWR);
  	int fdd = open("README", O_RDWR);
  	char* text=(char *)mmap(0, size, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_POPULATE, fd, 0);
  	char* text2;
  	int pid=fork();
  	if(pid==0){
  		text2 = (char *)mmap(8192, size, PROT_REAN|PROT_WRITE, MAP_PRIVATE|MAP_POPULATE|MAP_FIXED, fdd);
  		text2[48]='g';
  		printf(1,"child\n");
  		printf(1,"parent_info\n");
  		//for(i=0;i<64;i++) printf(1,"%c",text[i]);
  		printf(1,"child_info\n");
  		for(i=0;i<64;i++) printf(1,"%c",text2[i]);
  	}
  	else{
  		wait();
  		printf(1,"parent\n");
  		for(i=0;i<64;i++) printf(1,"%c", text[i]);
  	}
  	printf(1"finisj\n");
  	exit();
  
  }
  