unison-2.32.52 [options]

unison-2.32.52 root1 root2 [options]

unison-2.32.52 profilename [options]

unison-2.32.52-gtk [options]


This manual page briefly documents Unison, and was written for the Debian GNU/Linux distribution because the original program does not have a manual page. For a full description, please refer to the inbuilt documentation or the manuals in /usr/share/doc/unison2.32.52/. The unison-2.32.52-gtk binary has similar command-line options, but allows the user to select and create profiles and configure options from within the program.

Unison is a file-synchronization tool for Unix and Windows. It allows two replicas of a collection of files and directories to be stored on different hosts (or different disks on the same host), modified separately, and then brought up to date by propagating the changes in each replica to the other.

Unison offers several advantages over various synchronization methods such as CVS, Coda, rsync, Intellisync, etc. Unison can run on and synchronize between Windows and many UNIX platforms. Unison requires no root privileges, system access or kernel changes to function. Unison can synchronize changes to files and directories in both directions, on the same machine, or across a network using ssh or a direct socket connection.

Transfers are optimised using a version of the rsync protocol, making it ideal for slower links. Unison has a clear and precise specification, and is resilient to failure due to its careful handling of the replicas and its private structures.

The two roots can be specified using an URI or a path. The URI must follow the convention: protocol://[user@][host][:port][/path]. The protocol part can be file, socket, ssh or rsh.


All Unison options are long, starting with one dash (`-') only. A summary of options is included here. For a complete description, see the inbuilt documentation or the manuals in /usr/share/doc/unison2.32.52/.


automatically accept default (nonconflicting) actions


batch mode: ask no questions at all

-doc xxx

show documentation ('-doc topics' lists topics)

-follow xxx

add a pattern to the follow list

-force xxx

force changes from this replica to the other


synchronize group attributes

-ignore xxx

add a pattern to the ignore list

-ignorenot xxx

add a pattern to the ignorenot list


synchronize owner

-path xxx

path to synchronize

-perms n

part of the permissions which is synchronized

-prefer xxx

choose this replica's version for conflicting changes

-root xxx

root of a replica (should be used exactly twice)


print nothing except error messages


suppress status messages


exit immediately after the connection to the server


synchronize modification times


print version and exit

-addprefsto xxx

file to add new prefs to


add version number to name of unison on server

-backup xxx

add a pattern to the backup list

-backupcurr xxx

add a pattern to the backupcurr list

-backupcurrnot xxx

add a pattern to the backupcurrnot list

-backupdir xxx

directory for storing centralized backups

-backuploc xxx

where backups are stored ('local' or 'central')

-backupnot xxx

add a pattern to the backupnot list

-backupprefix xxx

prefix for the names of backup files


keep backup copies of all files (see also 'backup')

-backupsuffix xxx

a suffix to be added to names of backup files


ask about whole-replica (or path) deletes (default true)


ask for confirmation before commiting results of a merge


suppress the 'contacting server' message during startup

-copyprog xxx

external program for copying large files

-copyprogrest xxx

variant of copyprog for resuming partial transfers

-copyquoterem xxx

add quotes to remote file name for copyprog (true/false/default)

-copythreshold n

use copyprog on files bigger than this (if >=0, in Kb)

-debug xxx

debug module xxx ('all' -> everything, 'verbose' -> more)

-diff xxx

command for showing differences between files


When set, never use the chmod system call


do not change terminal settings in text UI

-fastcheck xxx

do fast update detection (true/false/default)

-forcepartial xxx

add a pattern to the forcepartial list

-height n

height (in lines) of main window in graphical interface

-host xxx

bind the socket to this host name in server socket mode

-ignorecase xxx

identify upper/lowercase filenames (true/false/default)


ignore locks left over from previous run (dangerous!)

-immutable xxx

add a pattern to the immutable list

-immutablenot xxx

add a pattern to the immutablenot list

-key xxx

define a keyboard shortcut for this profile (in some UIs)


kill server when done (even when using sockets)

-label xxx

provide a descriptive string label for this profile


record actions in logfile (default true)

-logfile xxx

logfile name

-maxbackups n

number of backed up versions of a file

-maxthreads n

maximum number of simultaneous file transfers

-merge xxx

add a pattern to the merge list

-mountpoint xxx

abort if this path does not exist


don't map uid/gid values by user/group names

-preferpartial xxx

add a pattern to the preferpartial list


Use creation times for detecting updates

-repeat xxx

synchronize repeatedly (text interface only)

-retry n

re-try failed synchronizations N times (text ui only)

-rootalias xxx

register alias for canonical root names

-rsrc xxx

synchronize resource forks (true/false/default)


activate the rsync transfer mode (default true)


run internal tests and exit

-servercmd xxx

name of unison executable on remote server


show 'true names' (for rootalias) of roots and archive

-socket xxx

act as a server on a socket


list changed files by size, not name

-sortfirst xxx

add a pattern to the sortfirst list

-sortlast xxx

add a pattern to the sortlast list


list new before changed files

-sshargs xxx

other arguments (if any) for remote shell command

-sshcmd xxx

path to the ssh executable

-ui xxx

select UI ('text' or 'graphic'); command-line only


optimize transfers using local copies (default true)

Some preferences are just boolean flags. Others take numeric or string arguments, indicated in the preferences list by n or xxx. Most of the string preferences can be given several times; the arguments are accumulated into a list internally.

RELATED TO unison-2.32…

The program is documented fully in the in-built documentation and the manual, available as text in /usr/share/doc/unison2.32.52/.


Options are automatically extracted from `unison -help'. The rest of this manual page was written by Robert McQueen <[email protected]>, for the Debian GNU/Linux system (but may be used by others).