ESQL & Data Replication

I am trying to determine the necessary steps I need to make to switch over from a primary to secondary database within my dynamic ESQL (C) code. I use INFORMIXSERVER environment variable for the primary, and DBPATH for secondary. What error codes return when a switch over occurs, either from primary to secondary or from secondary to primary? What do I need to do when I get an error; disconnect and reconnect? What happens to a cursor which was opened under primary, but the primary went down? Any help would be appreciated. Thanks in advance, Eric Moritz