ÿ
{IBM magtape label formats
{All labels are 80 bytes, EBCDIC

   %record %format label (               {VOLUME label}   %c
           %integer      vol1,           {m'VOL1', EBCDIC}
           %bytearray    serial no(1:6),
                         R1(1:1),        {Rn: reserved fields}
                         VTOC(1:10),     {ignored for tape volumes}
                         R2(1:20),
                         Owner(1:10),    {volume owner ID}
                         R3(1:29)        %c
      %or  %integer      Label1,         {HDR1/EOV1/EOF1}
           %byte %array  File(1:17),     {"data set identifier"}
                         File serial(1:6),   {Vol ID of vol. holding this file}
                         Vol seq(1:4),   {Volume no. within multi vol. set}
                         File seq(1:4),  {File seq no. within current volume}
                         Gen(1:4),       {Generation number}
                         Version(1:2),
                         Created(1:6),   { byyddd, b=blank, ddd=001-366 }
                         Expires(1:6),
           %byte         Lock,           {'0':no prot, '1','3':passwords}
           %byte %array  Blocks(1:6),    {File block count}
                         System(1:13),   {Name of system which wrote tape}
                         R4(1:7)         %c
      %or  %integer      Label2,         {HDR2/EOV2/EOF2 labels}
           %byte         Format,         {F(ixed),V(ariable),U(ndef) records}
           %byte %array  Block len(1:5),
                         Record len(1:5),
           %byte         Density,        { 0: 7-track/200 9-track/ -    } %c
                                         { 1:        /556        / -    } %c
                                         { 2:        /800        /800(NRZI)} %c
                                         { 3:        / -         /1600(PE) } %c
                                         { 4:        / -         /6250(GCR)} %c
                         DSP,            {Data set position (multi-reel only) }
           %byte %array  Job ID( 1:17),   {who wrote this tape?}
                         How(1:2),       {Tape recording conventions}
           %byte         Control,        {Control characters in dataset?}
                         R5,
                         Attrib,         {"B": Blocked records}   %c
                                         {"S": Spanned records}   %c
                                         {"R": Blocked & Spanned} %c
                                         {" ": No Blocked or spanned recs!} %c
           %byte %array  R6(1:8),
           %byte         Checkpoint,
           %byte %array  R7(1:32)        %c
      %or  %integer      User label,     {ha ha}
           %byte %array  R8(1:76))

%end %of %file