HARDLINK(1) HARDLINK(1) (NAME) hardlink - (SYNOPSIS) hardlink [options] directory|file... (DESCRIPTION) hardlink (hardlinks) (copy-on-write clones) . hardlink . . memcmp . ( SHA256) (Linux kernel crypto API) . <<>> (intro) (cache) . cache-size io-size . <<>> . (OPTIONS) -c, --content () . -pot . -b, --io-size size read(2) sendfile(2) . size KiB MiB . <> <> <> . memcmp 8KiB 1MiB . memcmp (zero-copy) / (I/O) . . -d, --respect-dir () . ( hardlink ) . hardlink --respect-dir /foo /bar /foo/some/file /bar/some/file /bar/other/file. --respect-name ( ) . -f, --respect-name () . -f hardlink . -F, --prioritize-trees . hardlink foo/ bar/ bar/ foo/ . -i, --include regex (regular expression) . --exclude . --exclude . -l, --list-duplicates (tab) . -m, --maximize (link count) . -M, --minimize . --mount ( ). -n, --dry-run . -o, --ignore-owner ( ) . . -O, --keep-oldest ( ) . . --maximize --minimize . -p, --ignore-mode (mode) . . -q, --quiet . -r, --cache-size size (cache) . memcmp ( --io-size ) . . 10MiB . --reflink[=when] ( reflink) . reflink . --ignore-owner --ignore-mode . --skip-reflinks . when never always auto . when auto hardlink BTRFS XFS ZFS reflink reflink . always reflink . --skip-reflinks . --reflink . -s, --minimum-size size . 1 . size KiB (=1024) MiB (=1024*1024) GiB TiB PiB EiB ZiB YiB (<> <> <> ). -S, --maximum-size size . 0 0 . size KiB (=1024) MiB (=1024*1024) GiB TiB PiB EiB ZiB YiB (<> <> <> ). -t, --ignore-time . . -v, --verbose . . . -x, --exclude regex . . --exclude-subtree regex . . -X, --respect-xattrs (xattrs) . -y, --method name . : sha256 sha1 crc32c memcmp. sha256 memcmp . . -z, --zero NUL ( -l). -h, --help . -V, --version . (ARGUMENTS) hardlink . (ENVIRONMENT) ULFILEEQ_DEBUG=all . (BUGS) hardlink -f . hardlink . hardlink . . hardlink . . hardlink . (AUTHOR) hardlink . Jakub Jelinek Fedora util-linux v2.34 v2.36 . Debian Julian Andres Klode . (REPORTING BUGS) . (AVAILABILITY) hardlink util-linux . util-linux 2.42.3 2026-09-02 HARDLINK(1)