What is the difference between Directory.systemTemp and getTemporaryDirectory from the path_provider (Flutter package), and in what situations should each be used?

[stephane-archer]

Both Directory.systemTemp and getTemporaryDirectory are commonly used to access temporary directories in Flutter applications, but they return different paths on some platforms.

This inconsistency can cause confusion for developers trying to decide which one to use.

Understanding why these methods behave differently and in which contexts they are appropriate is crucial for choosing the right tool for temporary file handling in a cross-platform environment.

Witch one should I pick and when?

[dart-github-bot]

Summary: User asks about Directory.systemTemp vs. path_provider's getTemporaryDirectory. They want to know the differences and appropriate usage scenarios for each.

[lrhn]

The obvious answer is that dart:io's Directory.systemTemp is whatever directory the authors of the VM considers the system tmp-directory on any given supported platform, and path_provider's getTemporaryDirectory is whatever that package's authors consider the tmp-directory on any supported platform.
(It's also non-idiomatically named).

Maybe reasonable people can disagree on what a "tmp-directory" means. Maybe one of them is "more right" than the other where they disagree.

The VM authors here can (maybe) tell what the dart:io design choices were. (Or those choices may predate the current dart:io maintainers.) They may not be able to explain where and why it differs from path_provider.
Might need to ask in both places to get the full story.

I think the biggest difference might be that path_provider is mockable. (But Directory.systemTemp can also be overridden using IOOverrides if you really want to.)

A very quick look does suggest that the VM treats Android as a Linux, with a very small difference, whereas path_provider use the Android cache directory, which is presumably more configurable than "/data/local/tmp".

(My guess is you should use path_provider for everything when writing Flutter apps, and use dart:io only if you're writing stand-alone Dart scripts.)

[stephane-archer]

Thank @lrhn for looking at this question. Do you know who are the current VM authors? Is this the right repository? More importantly, what was the motivation for path_provider authors to add getTemporaryDirectory? Is this only to be able to mock it easily? I see there are some other (minor?) differences.

[lrhn]

You'll have to ask the path_provider authors about their motivation.

The current owners of dart:io should be summoned by the library-io tag 😉