s3 access doesn't seem to completely work on darwin yet, but this gets further...

And anyway on linux the current code is broken against libc++

@edolstra @copumpkin

That's a lot of code for a little performance optimization :-(

C++ streams considered verbose 😦

Do we really need the full stream interface? Agree that it's awkwardly verbose but if we're using them in a non-standards compliant manner, they kind of work "by accident" and could break with future updates.

We're passing this to the aws sdk, which does expect a proper stream. And indeed on libc++ our current impl is broken due to broken compliance :(

If it helps, a lot of the verbosity is just boilerplate 👅

@edolstra ping

@edolstra Do we want to merge this, drop the optimization all together, or drop S3 support on libc++ based builds?