Bad address in my file I/O operation function - c

Question

I am learning Linux file I/O operation functions and trying to write a program that could creat a new file, read or write it as well as change the permissions and attributes of a file. When I try to use function "open(pathname, O_RDWR);" to get a file descriptor and use "read()" function to read current file, there is always "bad address" error. However, when I use "open(pathname, O_RDWR|O_CREATE,S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH)" before write, the file will be writen currectly.
Here are the source code when I using that two function.
//the welcome function is a function that serve as a function nemu bar
void Create()
{
char filepath[8];
int fd;
printf("请输入要创建的文件所在的目录及其名称：\n");
scanf("%s",&filepath);
fd = open(filepath, O_RDWR|O_CREAT, S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH );//总是以默认的方式创建文件
if(fd == -1)
{
printf("创建失败，请重新输入文件名及其所在目录创建\n");
sleep(5);
Create();
}
else
{
char is;
printf("创建成功！是否对新创建的文件进行写操作？");
scanf("%s",&is);
if(is == 'y'||is == 'Y')
Write(fd,filepath);
else if(is == 'n'||is == 'N')
{
close(fd);
welcome();
}
else
{
printf("您的输入有误，回到欢迎界面中…\n");
close(fd);
sleep(5);
welcome();
}
}
}
void Write(int fd, char *path)
{
volatile int len;
if(fd == -1)
{
len = 0;
char filepath[8];
printf("请输入要写的文件的完整路径及其名称：");
scanf("%s",&filepath);
fd = open(filepath, O_RDWR);
if(fd == -1)
{
perror("open during write");
Write(-1, "");
}
char w1[BUFFERSIZE], *w;
printf("请输入要写入文件的内容，以回车结束：\n");
scanf("%s",&w1);
w = w1;
//用于写入的模块
int n = 1;
while(n > 0)
{
if(n = write(fd, w+len, (strlen(w)-len))<0)
{
perror("write");
return;
}
len += n;
}
char is;
printf("是否查看写入的内容？");
scanf("%s",&is);
if(is == 'Y'||is == 'y')
{
close(fd);
Read(filepath,strlen(w));
}
else
{
close(fd);
welcome();
}
}
else
{
printf("请输入要写入文件的数据：\n");
char w1[BUFFERSIZE];
char *w;
scanf("%s",&w1);
w = w1;
len = 0;
int n = 1;
while(n > 0)
{
n = write(fd, w+len, (strlen(w)-len));
len += n;
}
char is;
printf("是否查看写入的内容？");
scanf("%s",&is);
if(is == 'Y'||is == 'y')
{
close(fd);
Read(path,strlen(w));
}
else
{
close(fd);
welcome();
}
}
};
Could you please help me solve this question? I would be highly appreciated if you could help me!