MSG_MORE socket.h flag

[Chance]

I've used cygwin in the past few years using the MSG_MORE flag when using
some socket functions but now it's not defined in cygwin\socket.h and
MSG_EOR is using the value of MSG_MORE (0x8000). Above that in the socket.h
file there is a comment /* MSG_EOR is not supported.  We use the
MSG_PARTIAL flag here */. I understand this as meaning MSG_EOR now works as
MSG_MORE would and that MSG_EOR is not usable. Just want some clarification
on this.