jdupes(1)
NAME
jdupes - finds and performs actions upon duplicate files
SYNOPSIS
jdupes [ options ] DIRECTORY ...
DESCRIPTION
Searches the given path(s) for duplicate files. Such files are found by comparing file sizes, then partial and full file hashes, followed by a byte-by-byte comparison.
OPTIONS
-A --nohidden
exclude hidden files from consideration
-B --dedupe
issue the btrfs same-extents ioctl to trigger a deduplication on
disk. The program must be built with btrfs support for this
option to be available
-D --debug
if this feature is compiled in, show debugging statistics and
info at the end of program execution
-d --delete
prompt user for files to preserve, deleting all others (see
CAVEATS below)
-f --omitfirst
omit the first file in each set of matches
-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
-h --help
displays help
-i --reverse
reverse (invert) the sort order of matches
-I --isolate
isolate each command-line parameter from one another; only match
if the files are under different parameter specifications
-L --hardlink
replace all duplicate files with hardlinks to the first file in
each set of duplicates
-m --summarize
summarize duplicate files information
-N --noprompt
when used together with --delete, preserve the first file in
each set of duplicates and delete the others without prompting
the user
-n --noempty
exclude zero-length files from consideration; this option is the
default behavior and does nothing (also see -z/--zeromatch)
-O --paramorder
parameter order preservation is more important than the chosen
sort; this is particularly useful with the -N option to ensure
that automatic deletion behaves in a controllable way
-o --order=WORD
order files according to WORD: time - sort by modification time
name - sort by filename (default)
-p --permissions
don't consider files with different owner/group or permission
bits as duplicates
-Q --quick
[WARNING: RISK OF DATA LOSS, SEE CAVEATS] skip byte-for-byte
verification of duplicate pairs (use hashes only)
-q --quiet
hide progress indicator
-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)
-r --recurse
for every directory given follow subdirectories encountered
within
-s --linksoft
replace all duplicate files with symlinks to the first file in
each set of duplicates
-S --size
show size of duplicate files
-s --symlinks
follow symlinked directories
-v --version
display jdupes version and compilation feature flags
-x --xsize=[+]SIZE
exclude files of size less than SIZE from consideration, or if
SIZE is prefixed with a '+' i.e. jdupes -x +226 [files] then
exclude files larger than SIZE. The following suffixes can be
used and are not case-sensitive:
`K' for kilobytes (units of 1024 bytes)
`M' for megabytes (units of 1024 x 1024 bytes)
`G' for gigabytes (units of 1024 x 1024 x 1024 bytes)
-z --zeromatch
consider zero-length files to be duplicates; this replaces the
old default behavior when -n was not specified
-Z --softabort
if the user aborts the program (as with CTRL-C) act on the
matches that were found before the abort was received. For
example, if -L and -Z are specified, all matches found prior to
the abort will be hard linked. The default behavior without -Z
is to abort without taking any actions.
NOTES
A set of arrows are used in hard linking to show what action was taken
on each link candidate. These arrows are as follows:
----> This file was successfully hard linked to the first file in the
duplicate chain
-@@-> This file was successfully symlinked to the first file in the
chain
-==-> This file was already a hard link to the first file in the chain
-//-> Linking this file failed due to an error during the linking
process
Duplicate files are listed together in groups with each file displayed
on a separate line. The groups are then separated from each other by
blank lines.
EXAMPLES
jdupes a --recurse: b
will follow subdirectories under b, but not those under a.
jdupes a --recurse b
will follow subdirectories under both a and b.
jdupes -O dir1 dir3 dir2
will always place 'dir1' results first in any match set (where
relevant)
CAVEATS
When using -d or --delete, care should be taken to insure against accidental data loss. -Z or --softabort used to be --hardabort in jdupes prior to v1.5 and had the opposite behavior. Defaulting to taking action on abort is probably not what most users would expect. The decision to invert rather than reassign to a different switch was made because this feature was still fairly new at the time of the change. The -O or --paramorder option allows the user greater control over what appears in the first position of a match set, specifically for keeping the -N option from deleting all but one file in a set in a seemingly random way. All directories specified on the command line will be used as the sorting order of result sets first, followed by the sorting algorithm set by the -o or --order option. This means that the order of all match pairs for a single directory specification will retain the old sorting behavior even if this option is specified. 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!). The -Q or --quick option only reads each file once, hashes it, and performs comparisons based solely on the hashes. There is a small but significant risk of a hash collision which is the purpose of the failsafe byte-for-byte comparison that this option explicitly bypasses. Do not use it on ANY data set for which any amount of data loss is unacceptable. This option is not included in the help text for the program due to its risky nature. You have been warned!
REPORTING BUGS
Send all bug reports to [email protected] or use the Issue tracker at http://github.com/jbruchon/jdupes/issues
AUTHOR
jdupes is a fork of 'fdupes' which is maintained by and contains extra code copyrighted by Jody Bruchon <[email protected]> jdupes was once called 'fdupes-jody' but the name was changed at the request of Adrian Lopez to avoid confusion between the two programs. Based on 'fdupes' created by Adrian Lopez <[email protected]> FDUPES(1)
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