Comment by marcosdumay

> It's a flaw in the design of Unix where polymorphic behaviour is achieved through file descriptors. Worse is better...

Looks to me it's a flaw on the signature of `write`. There should be a way to recover the status without changing the descriptor status, and there should be a way to ensure you get the final status, blocking if necessary.

This can even be fixed in a backwards compatible way, by creating a new pair of functions.