How can I pass argument as a pointer in Ruby? ( I mean the
h = Example.Flix2_CreateEx(....<how?>...,"localhost",0)
SWIG is able to handle pointers without any particular help. But if you need to be able to pass a FLIX2HANDLE (whatever that is) as an argument, then you need to wrap that in Ruby as well, using SWIG, so a Ruby object can be linked to a FLIX2HANDLE.
You might have a look at the SQLite3 SWIG wrapper. The SQLite3 C API makes extensive use of a db handle as a first argument, but the Ruby API makes a nice job of hiding this from the user.