FDUPES(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

-@ --loud
    output annoying low-level debug info while running

-1 --one-file-system
    do not match files that are on different filesystems or devices

-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 --linkhard
    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

-l --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 (NOTE: deprecated in favor of -X)
    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. Suffixes K/M/G can be used.

-X --exclude=spec:info
    exclude files based on specified criteria; supported specs are:

    `size[+-=]:number[suffix]'
        Match only if size is greater (+), less than (-), or equal to (=) the specified number, with an optional multiplier suffix. The +/- and = specifiers can be combined; ex :"size+=4K" will match if size is greater than or equal to four kilobytes (4096 bytes). Suffixes supported are K/M/G/T/P/E with a B or iB extension (all case-insensitive); no extension or an IB extension specify binary multipliers while a B extension specifies decimal multipliers (ex: 4K or 4KiB = 4096, 4KB = 4000.)

-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
Using -1 or --one-file-system prevents matches that cross filesystems, but a more relaxed form of this option may be added that allows cross-matching for all filesystems that each parameter is present on. 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 jody@jodybruchon.com 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 <jody@jodybruchon.com> 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 <adrian2@caribe.net>