fdupes - finds duplicate files in a given set of directories


   fdupes [ options ] DIRECTORY ...


   Searches  the  given  path for duplicate files. Such files are found by
   comparing file sizes and MD5 signatures,  followed  by  a  byte-by-byte


   -r --recurse
          for  every  directory  given  follow  subdirectories encountered

   -R --recurse:
          for each directory given after this option follow subdirectories
          encountered  within  (note the ':' at the end of option; see the
          Examples section below for further explanation)

   -s --symlinks
          follow symlinked directories

   -H --hardlinks
          normally, when two or more files point to  the  same  disk  area
          they are treated as non-duplicates; this option will change this

   -n --noempty
          exclude zero-length files from consideration

   -f --omitfirst
          omit the first file in each set of matches

   -A --nohidden
          exclude hidden files from consideration

   -1 --sameline
          list each set of matches on a single line

   -S --size
          show size of duplicate files

   -m --summarize
          summarize duplicate files information

   -q --quiet
          hide progress indicator

   -d --delete
          prompt user for files to  preserve,  deleting  all  others  (see
          CAVEATS below)

   -N --noprompt
          when  used  together  with  --delete, preserve the first file in
          each set of duplicates and delete the others  without  prompting
          the user

   -I --immediate
          delete duplicates as they are encountered, without grouping into
          sets; implies --noprompt

   -p --permissions
          don't consider files with different  owner/group  or  permission
          bits as duplicates

   -o --order=WORD
          order files according to WORD: time - sort by mtime, name - sort
          by filename

   -i --reverse
          reverse order while sorting

   -v --version
          display fdupes version

   -h --help
          displays help




   Unless -1 or  --sameline  is  specified,  duplicate  files  are  listed
   together  in groups, each file displayed on a separate line. The groups
   are then separated from each other by blank lines.

   When -1 or --sameline is specified,  spaces  and  backslash  characters
   (\) appearing in a filename are preceded by a backslash character.


   fdupes a --recurse: b
          will follow subdirectories under b, but not those under a.

   fdupes a --recurse b
          will follow subdirectories under both a and b.


   If  fdupes returns with an error message such as fdupes: error invoking
   md5sum it means the program  has  been  compiled  to  use  an  external
   program  to  calculate  MD5 signatures (otherwise, fdupes uses internal
   routines for this purpose), and an error has occurred while  attempting
   to  execute  it.  If  this is the case, the specified program should be
   properly installed prior to running fdupes.

   When using -d or --delete, care  should  be  taken  to  insure  against
   accidental data loss.

   When  used  together  with  options  -s  or  --symlink,  a  user  could
   accidentally preserve a symlink while deleting the file it points to.

   Furthermore, when specifying a particular directory more than once, all
   files  within  that  directory  will be listed as their own duplicates,
   leading to data  loss  should  a  user  preserve  a  file  without  its
   "duplicate" (the file itself!).


   Adrian Lopez <adrian2@caribe.net>



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