Layout of the queue.dat file

          File : queue.dat
 Queue Version : 5.01
          Size : 7168 bytes
    F@H Client : FAH502-Linux.exe

Index X - CPU ID

ID: 3539220A7A46065D
This ID is used by the server to identify the user's machine, and to validate the work unit when it is returned. The number stored in queue.dat, and printed here, is really the sum of the assigned UserID and the configured MachineID, as it was when the unit started. The ID actually sent to the server when the unit is uploaded is what is current at that time on the machine which does the upload. Ideally, it should match the ID to which the unit is assigned, to within the allowed configurable range of the MachineID, or the uploaded unit might be rejected. Recent experiments with transferring work among machines have shown the servers usually to be more permissive, but relying on this would probably be a bad idea.

When qd was written, it appeared that this ID was always stored in little-endian byte-order. This has turned out to not always be the case. Most of the time the ID is indeed stored as little-endian, but sometimes also as big-endian. This was seen on FreeBSD and OpenBSD in the indices of deleted WUs and elsewhere.

grep "464 Stored ID" qd.c
                char    uid[8];         /* 464 Stored ID for unit (UserID + MachineID) (LE or BE) */

./qd -q queue.dat | grep ID
  user: [DPC]_Fatal_Error_Group0smoking2000; team: 92; ID: 264AE04D5B242F72; mach ID: 1   # Index 3
  user: [DPC]_Fatal_Error_Group0smoking2000; team: 92; ID: 264AE04D5B242F72; mach ID: 1   # Index 4
  user: [DPC]_Fatal_Error_Group0smoking2000; team: 92; ID: 264AE04D5B242F72; mach ID: 1   # Index 5
  user: [DPC]_Fatal_Error_Group0smoking2000; team: 92; ID: 264AE04D5B242F72; mach ID: 1   # Index 6
  user: [DPC]_Fatal_Error_Group0smoking2000; team: 92; ID: 264AE04D5B242F72; mach ID: 1   # Index 7
  user: [DPC]_Fatal_Error_Group0smoking2000; team: 92; ID: 264AE04D5B242F72; mach ID: 1   # Index 8
  user: [DPC]_Fatal_Error_Group0smoking2000; team: 92; ID: 264AE04D5B242F72; mach ID: 1   # Index 9
  user: [DPC]_Fatal_Error_Group0smoking2000; team: 92; ID: 264AE04D5B242F72; mach ID: 1   # Index 0
  user: [DPC]_Fatal_Error_Group0smoking2000; team: 92; ID: 264AE04D5B242F72; mach ID: 1   # Index 1
  user: [DPC]_Fatal_Error_Group0smoking2000; team: 92; ID: 264AE04D5B242F72; mach ID: 1   # Index 2

hexdump -C -s 472 -n 8 queue.dat     # Index 0
000001d8  26 4a e0 4d 5b 24 2f 72                           |&JàM[$/r|
000001e0

hexdump -C -s 1184 -n 8 queue.dat    # Index 1
000004a0  26 4a e0 4d 5b 24 2f 72                           |&JàM[$/r|
000004a8

hexdump -C -s 1896 -n 8 queue.dat    # Index 2
00000768  26 4a e0 4d 5b 24 2f 72                           |&JàM[$/r|
00000770

hexdump -C -s 2608 -n 8 queue.dat    # Index 3
00000a30  26 4a e0 4d 5b 24 2f 72                           |&JàM[$/r|
00000a38

hexdump -C -s 3320 -n 8 queue.dat    # Index 4
00000cf8  26 4a e0 4d 5b 24 2f 72                           |&JàM[$/r|
00000d00

hexdump -C -s 4032 -n 8 queue.dat    # Index 5
00000fc0  26 4a e0 4d 5b 24 2f 72                           |&JàM[$/r|
00000fc8

hexdump -C -s 4744 -n 8 queue.dat    # Index 6
00001288  26 4a e0 4d 5b 24 2f 72                           |&JàM[$/r|
00001290

hexdump -C -s 5456 -n 8 queue.dat    # Index 7
00001550  26 4a e0 4d 5b 24 2f 72                           |&JàM[$/r|
00001558

hexdump -C -s 6168 -n 8 queue.dat    # Index 8
00001818  26 4a e0 4d 5b 24 2f 72                           |&JàM[$/r|
00001820

hexdump -C -s 6880 -n 8 queue.dat    # Index 9
00001ae0  26 4a e0 4d 5b 24 2f 72                           |&JàM[$/r|
00001ae8