I read this http://www.postgresql.org/docs/8.4/static/libpq-copy.html
I want to send the copy command and then send the data directly. the server don't send the PGRES_COPY_IN to the client.
While receive the copy in command, the server already know how to do. so the server begin to receive data directly.
While receive the copy to command, the server already know how to do. so the server begin to send data directly. And the client receive data directly.
So I want to delete the send of PGRES_COPY_IN or PGRES_COPY_OUT.
wait for your answers, thanks.