- Modify header content:
  - 32 bytes Tag string e.g. "ADIOS-BP v2.3.1 Index Table     "
  - byte 36 endianness
  - byte 37 BP version
  - byte 38 Active flag (in Index table it indicates active writer)
- bp4dbg print header for all files
- bp4dbg just seeks over real data instead of reading it