//po4a: entry man manual //// SPDX-License-Identifier: MIT Copyright (C) 2008 - 2012 Julian Andres Klode. See hardlink.c for license. Copyright (C) 2021 Karel Zak //// = hardlink(1) :doctype: manpage :man manual: User Commands :man source: util-linux {release-version} :page-layout: base :command: hardlink == NAME hardlink - link multiple copies of a file == SYNOPSIS *hardlink* [options] [_directory_|_file_]... == DESCRIPTION *hardlink* is a tool which replaces copies of a file with hardlinks, therefore saving space. == OPTIONS *-h*, *--help*:: print quick usage details to the screen. *-v*, *--verbose*:: More verbose output. If specified once, every hardlinked file is displayed, if specified twice, it also shows every comparison. *-q*, *--quiet*:: Quiet mode, don't print anything. *-n*, *--dry-run*:: Do not act, just print what would happen. *-f*, *--respect-name*:: Only try to link files with the same (basename). It's strongly recommended to use long options rather than *-f* which is interpreted in a different way by others *hardlink* implementations. *-p*, *--ignore-mode*:: Link/compare files even if their mode is different. This may be a bit unpredictable. *-o*, *--ignore-owner*:: Link/compare files even if their owner (user and group) is different. It is not predictable. *-t*, *--ignore-time*:: Link/compare files even if their time of modification is different. You almost always want this. *-X*, *--respect-xattrs*:: Only try to link files with the same extended attributes. *-m*, *--maximize*:: Among equal files, keep the file with the highest link count. *-M*, *--minimize*:: Among equal files, keep the file with the lowest link count. *-O*, *--keep-oldest*:: Among equal files, keep the oldest file (least recent modification time). By default, the newest file is kept. If *--maximize* or *--minimize* is specified, the link count has a higher precedence than the time of modification. *-x*, *--exclude* _regex_:: A regular expression which excludes files from being compared and linked. *-i*, *--include* _regex_:: A regular expression to include files. If the option *--exclude* has been given, this option re-includes files which would otherwise be excluded. If the option is used without *--exclude*, only files matched by the pattern are included. *-s*, *--minimum-size* _size_:: The minimum size to consider. By default this is 1, so empty files will not be linked. The _size_ argument may be followed by the multiplicative suffixes KiB (=1024), MiB (=1024*1024), and so on for GiB, TiB, PiB, EiB, ZiB and YiB (the "iB" is optional, e.g., "K" has the same meaning as "KiB"). == ARGUMENTS *hardlink* takes one or more directories which will be searched for files to be linked. == BUGS The original *hardlink* implementation uses the option *-f* to force hardlinks creation between filesystem. This very rarely usable feature is no more supported by the current hardlink. *hardlink* assumes that the trees it operates on do not change during operation. If a tree does change, the result is undefined and potentially dangerous. For example, if a regular file is replaced by a device, hardlink may start reading from the device. If a component of a path is replaced by a symbolic link or file permissions change, security may be compromised. Do not run hardlink on a changing tree or on a tree controlled by another user. == AUTHOR There are multiple *hardlink* implementations. The very first implementation is from Jakub Jelinek for Fedora distribution, this implementation has been used in util-linux between versions v2.34 to v2.36. The current implementations is based on Debian version from Julian Andres Klode. include::man-common/bugreports.adoc[] include::man-common/footer.adoc[] ifdef::translation[] include::man-common/translation.adoc[] endif::[]