MYSQLI_REFRESH_REPLICA
This constant has been added as a replacement for
MYSQLI_REFRESH_SLAVE,
in line with an upstream change in MySQL.
The old constant is still available for backwards-compatibility reasons,
but may be deprecated/removed in the future.
The following socket options are now defined if they are supported:
SO_ACCEPTFILTER
SO_DONTTRUNC
SO_WANTMORE
SO_MARK
TCP_DEFER_ACCEPT