验证csv文件是否已成功更新

I have trouble while updating a csv file (write), if there are any exception thrown such as system power may be also off or another app's reading the file. In this case, the reading side cannot judge whether csv file is updated completely or not. Is there any technique (format) to solve this problem ? I have research and see that we can add some keyword such as EOF(xxxx) if the file is updated successfully, but is there any idea that more standardize plz?I have trouble while updating a csv file (write