[thirdparty/util-linux.git] / misc-utils / hardlink.1

.TH "hardlink" "1"
.SH "NAME"
hardlink \- Consolidate duplicate files via hardlinks
.SH "SYNOPSIS"
.B hardlink
[options]
.RI [ directory ...]
.SH "DESCRIPTION"
.PP
This manual page documents \fBhardlink\fR, a
program which consolidates duplicate files in one or more directories
using hardlinks.
.PP
\fBhardlink\fR traverses one
or more directories searching for duplicate files.  When it finds duplicate
files, it uses one of them as the master.  It then removes all other
duplicates and places a hardlink for each one pointing to the master file.
This allows for conservation of disk space where multiple directories
on a single filesystem contain many duplicate files.
.PP
Since hard links can only span a single filesystem, \fBhardlink\fR
is only useful when all directories specified are on the same filesystem.
.SH "OPTIONS"
.TP
.BR \-c , " \-\-content"
Compare only the contents of the files being considered for consolidation.
Disregards permission, ownership and other differences.
.TP
.BR \-f , " \-\-force"
Force hardlinking across file systems.
.TP
.BR \-n , " \-\-dry\-run"
Do not perform the consolidation; only print what would be changed.
.TP
.BR \-v , " \-\-verbose"
Print summary after hardlinking. The option may be specified more than once. In
this case (e.g. \fB-vv\fR) it prints every hardlinked file and bytes saved.
.TP
.BR \-x , " \-\-exclude " \fIregex\fR
Exclude files and directories matching pattern from hardlinking.
.sp
The optional pattern for excluding files and directories must be a PCRE2
compatible regular expression. Only the basename of the file or directory
is checked, not its path. Excluded directories' contents will not be examined.
.TP
.BR \-h , " \-\-help"
Display help text and exit.
.TP
.BR \-V , " \-\-version"
Display version information and exit.
.SH "AUTHOR"
.PP
\fBhardlink\fR was written by Jakub Jelinek <jakub@redhat.com> and later modified by
Ruediger Meier <ruediger.meier@ga-group.nl> and Karel Zak <kzak@redhat.com> for util-linux.
.PP
Man page written by Brian Long and later updated by Jindrich Novy <jnovy@redhat.com>
.SH "BUGS"
.PP
\fBhardlink\fR assumes that its target directory trees do not change from under
it.  If a directory tree does change, this may result in \fBhardlink\fR
accessing files and/or directories outside of the intended directory tree.
Thus, you must avoid running \fBhardlink\fR on potentially changing directory
trees, and especially on directory trees under control of another user.
.PP
Historically \fBhardlink\fR silently excluded any names beginning with
".in.", as well as any names beginning with "." followed by exactly 6
other characters. That prior behavior can be achieved by specifying
.br
-x '^(\\.in\\.|\\.[^.]{6}$)'
.SH AVAILABILITY
The hardlink command is part of the util-linux package and is available from
https://www.kernel.org/pub/linux/utils/util-linux/.
Commit	Line	Data
cabf1c1c JN	1	.TH "hardlink" "1"
	2	.SH "NAME"
	3	hardlink \- Consolidate duplicate files via hardlinks
	4	.SH "SYNOPSIS"
98542119 KZ	5	.B hardlink
	6	[options]
	7	.RI [ directory ...]
cabf1c1c JN	8	.SH "DESCRIPTION"
cabf1c1c JN	9	.PP
f7c5507d	10	This manual page documents \fBhardlink\fR, a
cabf1c1c JN	11	program which consolidates duplicate files in one or more directories
	12	using hardlinks.
	13	.PP
f7c5507d	14	\fBhardlink\fR traverses one
cabf1c1c JN	15	or more directories searching for duplicate files. When it finds duplicate
	16	files, it uses one of them as the master. It then removes all other
	17	duplicates and places a hardlink for each one pointing to the master file.
	18	This allows for conservation of disk space where multiple directories
	19	on a single filesystem contain many duplicate files.
	20	.PP
f7c5507d	21	Since hard links can only span a single filesystem, \fBhardlink\fR
cabf1c1c JN	22	is only useful when all directories specified are on the same filesystem.
cabf1c1c JN	23	.SH "OPTIONS"
98542119 KZ	24	.TP
98542119 KZ	25	.BR \-c , " \-\-content"
cabf1c1c JN	26	Compare only the contents of the files being considered for consolidation.
cabf1c1c JN	27	Disregards permission, ownership and other differences.
98542119 KZ	28	.TP
98542119 KZ	29	.BR \-f , " \-\-force"
348af99a	30	Force hardlinking across file systems.
98542119 KZ	31	.TP
98542119 KZ	32	.BR \-n , " \-\-dry\-run"
cabf1c1c	33	Do not perform the consolidation; only print what would be changed.
98542119 KZ	34	.TP
	35	.BR \-v , " \-\-verbose"
	36	Print summary after hardlinking. The option may be specified more than once. In
f7c5507d	37	this case (e.g. \fB-vv\fR) it prints every hardlinked file and bytes saved.
98542119	38	.TP
f7c5507d	39	.BR \-x , " \-\-exclude " \fIregex\fR
551e8963	40	Exclude files and directories matching pattern from hardlinking.
98542119	41	.sp
551e8963 TL	42	The optional pattern for excluding files and directories must be a PCRE2
	43	compatible regular expression. Only the basename of the file or directory
	44	is checked, not its path. Excluded directories' contents will not be examined.
98542119 KZ	45	.TP
	46	.BR \-h , " \-\-help"
	47	Display help text and exit.
	48	.TP
	49	.BR \-V , " \-\-version"
	50	Display version information and exit.
cabf1c1c JN	51	.SH "AUTHOR"
cabf1c1c JN	52	.PP
f7c5507d	53	\fBhardlink\fR was written by Jakub Jelinek <jakub@redhat.com> and later modified by
98542119	54	Ruediger Meier <ruediger.meier@ga-group.nl> and Karel Zak <kzak@redhat.com> for util-linux.
cabf1c1c	55	.PP
bd9a35c6	56	Man page written by Brian Long and later updated by Jindrich Novy <jnovy@redhat.com>
94b040b0 JN	57	.SH "BUGS"
94b040b0 JN	58	.PP
f7c5507d KZ	59	\fBhardlink\fR assumes that its target directory trees do not change from under
f7c5507d KZ	60	it. If a directory tree does change, this may result in \fBhardlink\fR
94b040b0	61	accessing files and/or directories outside of the intended directory tree.
f7c5507d	62	Thus, you must avoid running \fBhardlink\fR on potentially changing directory
94b040b0	63	trees, and especially on directory trees under control of another user.
551e8963	64	.PP
f7c5507d	65	Historically \fBhardlink\fR silently excluded any names beginning with
551e8963 TL	66	".in.", as well as any names beginning with "." followed by exactly 6
	67	other characters. That prior behavior can be achieved by specifying
	68	.br
5aad3c12	69	-x '^(\\.in\\.\|\\.[^.]{6}$)'
bd9a35c6 KZ	70	.SH AVAILABILITY
	71	The hardlink command is part of the util-linux package and is available from
	72	https://www.kernel.org/pub/linux/utils/util-linux/.