My C:\temp is so full of stuff, some unknown amount of which turned out to be not as temp as I first thought, that I've now had to create C:\verytemp for the really temp stuff, which I make sure is emptied daily.

Some 20 years ago, when HD space was at a premium, I wrote a small script to clear out various temp directories in Windows 98. I tested the deployment on a colleague's computer, only to have him inform me that he used c:\temp as "temporary storage for projects I'm working on". Oh, well.

I actually have a tmp on my desktop for this very purpose :-)

If you go back far enough then calling GetTempPath() from the win32 API would return C:\Temp. It was always meant as a place for programs to put temporary files, not for users to stuff their garbage.

That reminds me of the early days of me doing sysadmin.

We had a BSD system and an Ultrix system. For convenience I temporarily NFS mounted the root of the Ultrix system into /tmp/foo on the BSD machine. After I was done I forgot to umount the volume.

The next day, the Ultrix machine behaved really weird. Things seemed to work fine, but a lot of files were missing. It took a bit of troubleshooting before we figured out what had happened.

As it turns out, the nightly /tmp cleanup script had run on the BSD machine, and this script deleted all files which had not been accessed in a week. Of course the script had traversed the NFS mount and cleaned up everything on the root disk of the other machine. This meant that all the files that were commonly used were still there, so things seemed fine until you tried to do anything that involved files that hadn't been touched in the last week.

That's when I learned never to use /tmp for anything important.

Not a windows user. Is this directory automatically emptied on reboot or something?

No but various programs will store and delete files in the temporary folder. Also if you use the disk cleanup utility it will clear them out. I think from Windows XP onwards it was moved out of the root to somewhere somewhat harder to find.

Of course it was never meant as a place to store users files temporarily, it was always for programs that needed to write a temporary file.

You joke, but I have seven git repository checkouts there right now. It’s a convenient place to put things I don’t want polluting my drive forever or being backed up, but need to exist on my filesystem at some point.

On Windows, you can make a temp folder in appdata/local and use that - local is specifically for files that don't get backed up. Actual temp folders can get deleted at any time.

Let's face it. We've all been there.