In the process of reviewing the tcp provider, I came across a problem mapping
socket calls to windows versions of the calls. (Gasp - I was shocked too)*.
This highlighted an issue that struct iovec doesn't seem to be defined by any
windows header files.
Internally, libfabric defines struct
> variable-sized means underflow?
It means that the receiver has no idea how large of a message to expect until
it is sent. (Hey, I made up the term). The problem is that every app is
ending up needing to implement a rendezvous protocol, which is layered over
libfabric, which also implements
