Replace `errno::Error` with `io::Error`?

[exrook]

Is there a reason errno::Error is used instead of std::io::Error?

I've created a branch replacing errno::Error with io::Error. The main changes were: replacing errno::Error::new() with io::Error::from_raw_os_error() and replacing errno::Error::last() with errno::Error::last_os_error()

The only major change is that io::Error does not implement PartialEq so either ErrorKind or raw_os_error() needs to be used to compare errors.

This is a breaking change for consumers of this crate, but io::Error provides all the same functionality with different method names, so upgrading should be straightforward.

[andreeaflorescu]

We were previously using io::Error and we switched to errno instead. It was annoying that io::Error does not implement PartialEq, we use it quite a lot to test that the errors returned from a functions are the expected ones.

[connorkuehl]

@exrook Starting from v0.6.1 (80abb6f6264e254fb627d211f62f179ce4299c10), client code should be able to convert between io::Error and errno::Error seamlessly. Does this help your use case?

[andreeaflorescu]

@exrook I'll be closing this, please re-open if it is still needed.