#include <db.h> int DB_MPOOLFILE->set_ftype(DB_MPOOLFILE *mpf, int ftype);
         The DB_MPOOLFILE->set_ftype() method specifies a file type for the
         purposes of input or output processing of the file's pages as they are
         read from or written to, the backing filesystem store.
    
         The DB_MPOOLFILE->set_ftype() method configures a file in the 
         cache, not only operations performed using the specified 
         DB_MPOOLFILE  handle.
    
         The DB_MPOOLFILE->set_ftype() method may not be called after the
         DB_MPOOLFILE->open() 
         method is called. If the file is already open in the cache when
         DB_MPOOLFILE->open()  is
         called, the information specified to DB_MPOOLFILE->set_ftype() will
         replace the existing information.
    
         The DB_MPOOLFILE->set_ftype() 
            
                  method returns a non-zero error value on failure and 0 on success.
            
            
        
    
The ftype parameter sets the file's type for the purposes of input and output processing. The ftype must be the same as a ftype parameter previously specified to the DB_ENV->memp_register() method.