fdupes: correct description of -rH to 'consider hardlinks'

[daniel-birket]

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This corrects the description of 'fdupes -rH', which causes fdupes to consider hardlinks as duplicates. fdupes is not designed to convert duplicate files to hardlinks as implied by the original description.

❯ fdupes --version
fdupes 2.3.2

❯ fdupes --help
Usage: fdupes [options] DIRECTORY...

 -r --recurse            for every directory given follow subdirectories
                         encountered within
 -R --recurse:           for each directory given after this option follow
                         subdirectories encountered within (note the ':' at the
                         end of the option, manpage for more details)
 -s --symlinks           follow symlinks
 -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 behavior

The pertinent code is:

file_t **checkmatch(filetree_t **root, filetree_t *checktree, file_t *file)
{
  int cmpresult;
  char *fullpath;

  if (ISFLAG(flags, F_CONSIDERHARDLINKS))
  {
    /* If node already contains file, we don't want to add it again.
    */
    if (has_same_file(checktree, file))
      return NULL;
  }
  else
  {
    /* If device and inode fields are equal one of the files is a
       hard link to the other or the files have been listed twice
       unintentionally. We don't want to flag these files as
       duplicates unless the user specifies otherwise.
    */
    if (is_hardlink(checktree, file))
      return NULL;
  }

[CLAassistant]

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[spageektti]

LGTM, thanks for your contribution.