What is the advantage of "safe write" in JetBrains IntelliJ?

Question

IntelliJ has a "safe write" option (quotes theirs, for some reason) which, on save, instead of simply updating the file, writes to a temporary file, then deletes the original, then renames the temporary file to the original's name. I hear that vim also does this.

I know this causes problems with programs that are watching the file. Sometimes such programs see the delete, but never see the update, for example.

But what advantages are there? IntelliJ's docs say that there are advantages that would be lost if you turned it off. There must be some reason this option is the default.

It took me a looong time to figure out this was how intellij operated and that it was causing some chronic issues I was facing, and took me even longer to figure out it was an option I could turn off. Now that I have that option, I'd like to know if the cure is worse than the disease, so to speak.

Answer 1

The safe write prevents you from data loss in case something goes wrong during the update. Just think of your computer or IntelliJ crashing while you are saving the file. You might lose the file completely then. But with safe write, you would lose your recent changes only. After the updated version of your file is written to disk without errors, the old version can be replaced. This way, you have a valid file version at any point of time during the update process, so no crash or whatever could make you lose all your work on that file. The worst thing which could happen is the loss of your recent changes.