File persisted with 600 permissions

[MarinPostma]

I have noticed that the permission of a persisted NamedTempFile is 600, but I was expecting it to be 644 (default permissions when creating a file).

I could be mistaken, but i found no mention of that in the doc? Maybe this could be part of the persist documentation?

I can issue a PR if needed.

[Stebalien]

More documentation would definitely be helpful. Specifically:

1. We need documentation on NamedTempFile::new explaining the default mode.
2. We need documentation on Builder explaining the defaults.
3. We need documentation on persist stating that it leaves the mode as-is (e.g., defaults to 600).

Unfortunately, I can't think of a good way to actually change this behavior:

1. We assume that the tempfile directory may be shared, so we create files with 600.
2. If we change the mode after persisting, the operation wouldn't be atomic, which may cause even harder to track down issues.

Ideally, we'd, provide a way to set the default mode in the Builder. There was a patch to do this, but, IIRC, it wasn't cross platform.

[assarbad]

@Stebalien do you know where to find said patch? Perhaps there's a way to make it cross-platform.

[Stebalien]

@assarbad https://github.com/Stebalien/tempfile/pull/61

[Stebalien]

We can now set default permissions (Builder::permissions), so I'll consider this fixed.