文件读写操作

#include
#include
#include
#include
#define ll long long
int main()
{
	char file_name[200]="C:\Users\165226\Desktop\cs.txt";
	FILE * fp=fopen (file_name, "w") ; //打开文件
    int c; //c:接收fgetc的返回值，定义为int，而非char M
    if(NULL==fp)
    {
        printf ("Failed tO open the file !n");
       return 0;
    }
 char str[5];
    for(int i=1;i<=10000000;i++)
    {
        str[0]=(rand()%26+'a');
        str[1]=',';
        int p=rand()%100;
        if(p>9)
        {
            str[2]=p/10+'0';
            str[3]=p%10+'0';
        }
        else
        {

            str[2]=p+'0';
        }
        int len=strlen(str);
        fwrite(str,len,1,fp);
        fputc(10,fp);
//        printf("%s====%d---%dn",str,i,strlen(str));

    }

    fclose(fp);
}