#include <db_cxx.h> int DbEnv::memp_fcreate(DbMpoolFile **dbmfp, u_int32_t flags);
        The DbEnv::memp_fcreate() method creates a 
        DbMpoolFile  structure that is the handle for a Berkeley DB
        cache (that is, a shared memory buffer pool file).  A pointer to this structure is returned in the memory to
        which dbmfp refers. Calling the 
        DbMpoolFile::close()  method will discard the returned handle.
    
         The DbEnv::memp_fcreate() 
            
            
                method either returns a non-zero error value or throws an
                exception that encapsulates a non-zero error value on
                failure, and returns 0 on success.