Handling Temporary Files, Best Practice

by Dmitry Kirsanov 9. October 2016 05:59

Each day I am creating so many temporary files that I can’t really give you a count. Sometimes it’s thousands. Opening attachments from e-mails and instant messengers, saving images from internet for a single use, opening archives, deploying software and many other tasks – they all create temporary files that may stay in a hard drive for years.

By temporary files I don’t mean the files created by applications to temporarily store data. I mean the actual user files you don’t intend to use in the future.

Another type of temporary files is log files. Usually we have them on servers. Web server logs, mail server, your own application that creates a set of log files each day – usually you don’t need to store these files for more than a few months. Especially if these files are stored on virtual machines, like Azure or Amazon, where you are paying for each megabyte of storage.

There are two aspects in temporary files that may justify doing something about them:

1. They take space or they are produced in numbers that decrease the performance of file system. The file doesn’t have to take all the space of the drive – it’s enough to have thousands of files in one directory to make Windows freeze every time it’s trying to find and list these files. For some directories we would prefer to have a threshold of a particular time after which these files should vanish.

2. They may contain sensitive information that you wouldn’t want to leave behind. Of financial, medical, business, political or any other nature – when the file has expired, there is no need to keep it, but some files may require special care in form of secure erase. More...