: buftype ( buf ln -- )
    3 OVER AT-XY KEY DUP EMIT
    DUP 0x20 < IF 2DROP DROP EXIT THEN
    ( buf ln c ) 4 col- nspcs SWAP 4 SWAP AT-XY ( buf c )
    SWAP C!+ IN( _zbuf (rdln) IN( SWAP 63 MOVE ;