!Direct-access disc block I/O specs

%external %predicate %spec EXISTS        (%string(25) file name)
%external %routine %spec   DELETE FILE   (%string(25) file name)
%external %routine %spec   RENAME FILE   (%string(25) old name, new name)
%external %routine %spec   NEW FILE   (%string(25) file name,
                                          %integer initial size,
                                          %integername ACtual)
%external %string(15) %fn %spec ITOS     (%integer x, y)
%external %integer %fn %spec    STOI     (%string(15) S)
%external %record(parm fm) %fn %spec PACKED (%string(25) filename)
%external %routine %spec   OPEN DA       (%integer chan, rw, %string(25) file)
%external %routine %spec   READ DA       (%integer chan, block number,
                                          %name buffer)
%external %routine %spec   WRITE DA      (%integer chan, block number,
                                          %name BUffer)
%external %routine %spec   EXTEND DA     (%integer chan, extent, %integername F)
%external %routine %spec   CLOSE DA      (%integer chan)
%end %of %file