#include <db_cxx.h> int DbMpoolFile::set_lsn_offset(int32_t lsn_offset);
         The DbMpoolFile::set_lsn_offset() method specifies the zero-based
         byte offset of a log sequence number  
         (DbLsn) on the file's pages, for
         the purposes of page-flushing as part of transaction checkpoint.  (See
         the DbEnv::memp_sync() 
         documentation for more information.)
    
         The DbMpoolFile::set_lsn_offset() method configures a file in the
         cache, not only operations performed using the specified 
         DbMpoolFile  handle.
    
         The DbMpoolFile::set_lsn_offset() method may not be called after the
         DbMpoolFile::open() 
         method is called. If the file is already open in the cache when
         DbMpoolFile::open()  is
         called, the information specified to DbMpoolFile::set_lsn_offset()
         must be consistent with the existing file or an error will be returned.
    
         The DbMpoolFile::set_lsn_offset() 
            
            
                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.