fiz

NAME

       fiz - analyze damaged zoo archive for data revovery

SYNOPSIS

       fiz archive[.zoo]

DESCRIPTION

       Fiz  is  used  to  analyze damaged zoo archives and locate
       directory entries and file data in them.  The current ver-
       sion  of fiz is 2.0 and it is meant to be used in conjunc-
       tion with zoo version 2.0.  Fiz makes no assumptions about
       archive structure.  Instead, it simply searches the entire
       subject archive for tag values that mark the locations  of
       directory  entries  and  file  data.   In a zoo archive, a
       directory entry contains information about a  stored  file
       such  as  its  name,  whether  compressed  or not, and its
       timestamp.  The file data are  the  actual  data  for  the
       archived file, and may be either the original data, or the
       result of compressing the file.

       For each directory entry found, fiz prints  where  in  the
       archive  it is located, the directory path and filename(s)
       found in it, whether the directory  entry  appears  to  be
       corrupted  (indicated  by [*CRC Error*]), and the value of
       the pointer to the file data that is found in  the  direc-
       tory  entry.   For  each  block  of file data found in the
       archive, fiz prints where in the archive the block begins.
       In  the  case of an undamaged archive, the pointer to file
       data found in a directory entry will correspond  to  where
       fiz actually locates the data.  Here is some sample output
       from fiz:

       ****************
           2526: DIR  [changes] ==>   95
           2587: DATA
       ****************
           3909: DIR  [copyrite] ==> 1478
           3970: DATA
           4769: DATA
       ****************

       In such output, DIR indicates where fiz found a  directory
       entry  in  the archive, and DATA indicates where fiz found
       file data in the archive.  Filenames located  by  fiz  are
       enclosed  in  square brackets, and the notation "==>   95"
       indicates that the directory entry found by fiz  at  posi-
       tion  2526  has  a  file  data pointer to position 95.  In
       actuality, fiz found file data at  positions  2587,  3970,
       and 4769.  Since fiz found only two directory entries, and
       each directory entry corresponds to one file, one  of  the
       file data positions is an artifact.

       Once  the locations of directory entries and file data are
       found, the @ modifier to zoo's archive  list  and  extract
       commands  can be used and the archive contents selectively
       listed or extracted, skipping the damaged  portion.   This
       is further described in the documentation for zoo(1).

       In  the above case, commands to try giving to zoo might be
       x@2526,2587 (extract beginning at position 2526,  and  get
       file  data  from  position  2587), x@3090,3970 (extract at
       3090, get data from  3970)  and  x@3909,4769  (extract  at
       3909,  get  data  from  4769).   Once  a correctly-matched
       directory entry/file data pair is found, zoo will in  most
       cases  synchronize  with  and  correctly extract all files
       subsequently found in the archive.  Trial and error should
       allow all undamaged files to be extracted.  Also note that
       self-extracting archives  created  using  sez  (the  Self-
       Extracting  Zoo  utility  for  MS-DOS), which are normally
       executed on  an  MS-DOS  system  for  extraction,  can  be
       extracted on non-MSDOS systems in a similar way.

SEE ALSO

       zoo(1)

BUGS

       Random  byte patterns can occasionally be incorrectly rec-
       ognized as tag values.  This occurs very rarely,  however,
       and trial and error will usually permit all undamaged data
       to be extracted.

DIAGNOSTICS

       Fiz always exits with a status code of 0.

FUTURE DIRECTIONS

       Automation of data recovery  from  a  damaged  archive  is
       potentially  achievable.   However, since damaged archives
       occur only rarely, fiz as it currently stands is  unlikely
       to change much in the near future.

AUTHOR

       Rahul Dhesi