clone(1)                    User's Reference Manual                   clone(1)

     clone — A file tree cloning tool

     clone [-c roff|woff|rwoff] [-d|-i|-s] [-v level] [-x exclude-list]
           [-X excl-list-file] [-y] [-h|-?|?] source/ destination/

     clone is a file tree cloning tool which runs 3 threads - a scheduler
     (main), a reader, and a writer thread. Reading and writing occurs in
     parallel. While this is most beneficial for copying data from one
     physical disk to another, clone is also very well suited for cloning a
     file tree to any place on the same disk.

     Cloning includes the whole directory hierarchy, i.e. sub-directories,
     files, hard links, symbolic links, attributes (modes, flags, times),
     extended attributes and access control lists.

     clone is useful for cloning (thus backing-up) live file systems, and it
     can also be used in incremental and synchronization mode.

     clone works on FreeBSD and Mac OS X.

     clone is very fast, for example, cloning a whole UFS2 file hierarchy on
     FreeBSD 9.1 of in total 2.3 TBytes of data from one hard disk to another
     took 7.5 h, so the average transfer rate for all kind of files (very
     small up to very big ones) was about 89 MByte/s.

     Optional flags:

     -c roff | woff | rwoff
              Selectively turn off the file system cache for reading or
              writing or for reading and writing -- the caches are on by

     The options -d, -i, -s are mutually exclusive:

     -d       Delete the contents of the destination before cloning, but do
              not remove the destination directory or mount point itself. Stop
              on error. Deletion requires user confirmation, unless it is
              confirmed inherently by the -y flag. Be careful, deletion cannot
              be undone! NOTE: It may take its time to empty hugh file trees,
              and it may be faster to use newfs(8) for initializing big

     -i       Incrementally add new content to or change content in the
              destination, but do not touch content in destination that does
              not exist in source.

     -l       Don't copy, but create hard links of regular files in the cloned
              directory tree.

     -s       Completely synchronize destination with source.

     -v       Verbosity level (default = 1):
              0 - no output
              1 - show directory action: + for add, - for delete, = for keep
              2 - indicate cloned files by '.'
              3 - display the path names of cloned file system items

     -x exclude-list
              Colon separated list of entity names or full path names to be
              excluded from cloning. Use full path names to single out exactly
              one item. Use entity names for all existing entities having that
              name being excluded.
              For example: -x ".snap:/.sujournal:.DS_Store:/fullpath/to
              a/volatile cache"

     -X excl-list-file
              File containing a list of entity names or full path names to be
              excluded -- one item per line.

     -y       Automatically answer with y(es) to y|n confirmation prompts.

     -h | -? | ?
              Show the usage instructions.

     Required arguments:

     source/  Path to the source directory or mount point to be cloned. The
              final '/' may be omitted.

              Path to the destination directory or mount point. If the
              destination does not exist, then it will be created. The final
              '/' may be omitted.

     Initial cloning of the root volume / to a volume mounted on /mnt:
              clone / /mnt

     Same as above, but empty /mnt before cloning:
              clone -d / /mnt

     Incrementally update the clone with respect to the master:
              clone -i / /mnt

     Keep the clone exactly synchronized to the master:
              clone -s / /mnt

     Create a non-versioned clone of a versioned source tree:
              clone -x .svn /path/to/my/project /path/to/non-versioned/project

     Clone a directory to a share and strip file system specific meta data:
              clone -x ".DS_Store:.AppleDouble:.AppleDesktop:.appdisk"
              /path/to/afpvol /path/to/the/share

     cp(1), ditto(1), rsync(1), dd(1), newfs(8), dump(8), restore(8), asr(8)

     Dr. Rolf Jansen. Copyright (c) 2013-2017. All rights reserved.

     Improper use of clone may delete or overwrite data. Take special care
     with the -d and the -s option. Also always be sure, that the last command
     line argument designates a path to a file tree which really is under

     In NO event shall the author and/or copyright owner be liable for ANY
     damages resulting from ANY use of this software. Use clone at your own

     clone has been carefully developed and tested. Anyway, clone is provided
     without any expressed or implied warrantee on being 100 % bug free.

FreeBSD, Darwin                 August 9, 2020                 FreeBSD, Darwin