As mentioned, this function returns a status bitfield to which there's a set of constants available. I don't know why those constants aren't actually listed. Although they're easy to guess, I think it's still worth listing them, it is documentation after all. This function has the ability to return integers 0 through 3 so there are 4 possible states.
The constants are as follows:
CONNECTION_NORMAL = 0
CONNECTION_ABORTED = 1
CONNECTION_TIMEOUT = 2
As a 4th state is possible and being a bitfield, this gives rise to CONNECTION_ABORTED|CONNECTION_TIMEOUT (or integer 3) can be used to check for aborted+timeout states.