#include <db.h>
int
DB_ENV->txn_checkpoint(const DB_ENV *env,
    u_int32_t kbyte, u_int32_t min, u_int32_t flags);  
      
         If there has been any logging activity in the database environment
         since the last checkpoint, the DB_ENV->txn_checkpoint() method
         flushes the underlying memory pool, writes a checkpoint record to the
         log, and then flushes the log.
    
         The DB_ENV->txn_checkpoint() method returns a non-zero error value on
         failure and 0 on success.
    
         The DB_ENV->txn_checkpoint() method is the underlying method used by
         the db_checkpoint
         utility. See the db_checkpoint utility
         source code for an example of using DB_ENV->txn_checkpoint() in a
         IEEE/ANSI Std 1003.1 (POSIX) environment.
    
If the kbyte parameter is non-zero, a checkpoint will be done if more than kbyte kilobytes of log data have been written since the last checkpoint.
If the min parameter is non-zero, a checkpoint will be done if more than min minutes have passed since the last checkpoint.
                         The DB_ENV->txn_checkpoint() 
            
                 method may fail and return one of the following non-zero errors: