filenum:=FOPEN(filename  {array of 36 bytes}
   ,foptions             {logical value, file options}
   ,aoptions             {logical value, access options}
   ,recsize              {integer value,+=words,-=bytes}
   ,device               {array of 8 bytes}
   ,formsmsg             {array of bytes}
   ,userlabels           {integer value, 0 to 255}
   ,blockfactor          {integer value, 1 to 255}
   ,numbuffers           {integer value, 0 to 16}
   ,filesize             {double value, maximum records}
   ,numextents           {integer value,1 to 32}
   ,initalloc            {integer value, starting extents}
   ,filecode             {integer value, file type code}
);                       {option variable}