|  | # add extra fields | 
|  | args testfile.zip  set_extra 0 2345 65535 cl extra1  set_extra 0 2345 65535 cl extra2  set_extra 0 2345 0 c extra1c  set_extra 0 2345 1 l extra2l  get_extra_by_id 0 2345 0 c  get_extra_by_id 0 2345 1 c  get_extra_by_id 0 2345 0 l  get_extra_by_id 0 2345 1 l | 
|  | return 0 | 
|  | file testfile.zip testfile.zip testfile-plus-extra.zip | 
|  | stdout Extra field 0x0929: len 7, data 0x65787472613163 | 
|  | stdout Extra field 0x0929: len 6, data 0x657874726132 | 
|  | stdout Extra field 0x0929: len 6, data 0x657874726131 | 
|  | stdout Extra field 0x0929: len 7, data 0x6578747261326c |