#include <db.h> int DB_CHANNEL->close(DB_CHANNEL *channel, u_int32_t flags);
        The DB_CHANNEL->close() method 
        closes the DB_CHANNEL handle, freeing any resources
        allocated to the handle. All DB_CHANNEL handles must be
        closed before the encompassing environment handle is closed.
        Also, all on-going messaging operations on the channel should be
        allowed to complete before attempting to close the channel handle.
    
         After DB_CHANNEL->close() has been
         called, regardless of its return, the DB_CHANNEL handle may
         not be accessed again.
    
         The DB_CHANNEL->close() 
            
                  method returns a non-zero error value on failure and 0 on success.
            
            
        
    
            The DB_CHANNEL->close()
            
            
                 method may fail and return one of the following non-zero errors: