Description
string 
db2_conn_errormsg ( [resource connection] )
   db2_conn_errormsg() returns an error message and SQLCODE
   value representing the reason the last database connection attempt failed.
   As db2_connect() returns FALSE in the event of a failed
   connection attempt, do not pass any parameters to
   db2_conn_errormsg() to retrieve the associated error
   message and SQLCODE value.
  
   If, however, the connection was successful but becomes invalid over time,
   you can pass the connection parameter to retrieve
   the associated error message and SQLCODE value for a specific connection.
  
Return Values
   Returns a string containing the error message and SQLCODE value resulting
   from a failed connection attempt. If there is no error associated with the last
   connection attempt, db2_conn_errormsg() returns an empty
   string.