NEWS.md

UNISON NEWS

This file contains a summary of user-visible or important changes, in the style of the GNU coding standards. By user-visible, we include changes relevant for those building unison from source. We omit most bugfixes and minor improvements, but of course every release contains some. Refer to the documentation for details; this file is a terse notice of changes rather than a tutorial about new features.

As of 2022, this file (NEWS.md at top level) is used for news.

Some software has a "changelog" file that records all changes, but unison uses git history for that, and thus there is no changelog file.

Changes in 2.53.3

Released 2023-04-28

• On Linux, allow syncing the xattrs where POSIX draft ACLS are stored, which enables syncing the ACL info. (Note that this does not enable syncing ACLs with the -acl switch, and does not enable syncing ACLs between other systems and Linux. See the manual.)
• Improved ETA calculation and sync speed display in text UI.
• Fix CI Windows builds (again).
• Drop unmaintained "make install" target.
• Bugfixes, minor improvements, cleanups.

Changes in 2.53.2

Released 2023-03-20

• Change version string to 2.53.2 (2.53.1 identified as 2.53.0).

Changes in 2.53.1

Released 2023-03-19

• Repeat mode is more fault tolerant, recovering after temporary errors.
• Preferences "force", "prefer" and related no longer require specifying the full root.
• Improve stopping of update propagation.
• Enable VT input escape codes in Windows.
• Respect user-provided CFLAGS, CPPFLAGS, LDFLAGS, LDLIBS.
• Add build instructions in INSTALL.md (and drop from manual).
• Add graceful stop in repeat mode - SIGUSR2.
• Add watch+seconds to 'repeat' preference.

Changes in 2.53.0

Released 2022-11-07

• OCaml >= 4.08 is required to build unison.
• unison can be built with (unreleased) OCaml 5.
• Change GUI to use GTK3 (via lablgtk3) instead of GTK2 (via lablgtk2)
• Add support for syncing extended attributes.
• Add support for syncing ACLs.
• On Windows, add the ability to build unison as a hybrid application (GUI application attached to a text console) by defining UI_WINOS=hybrid (see src/Makefile). Add this to CI. (Doing this for non-Windows is unnecessary as all applications, both GUI and non-GUI, are always executed with a connection to stdout/stderr. GUI-only applications (ie, no stdout/stderr) is a Windows-only concept.)
• Notable bugfixes
  • Merge results are stored in archive more accurately.
  • Windows \\?\ paths now work correctly (including \\?\Volume{GUID}\ paths).
• CI changes
  • The macOS binaries are properly signed.
  • Add workaround for bugs in the github CI Windows builds, one of which resulted in the 2.52.1 GUI version failing, in the Windows CI build artifacts. (This does not affect platforms other than Windows, and may not affect other Windows builds.)
• Changes that should not affect behavior
  • Clean up a variety of unmaintained and unused bits, mainly build-related.
  • OCaml's Unix library is now extensively used also on Windows. This allowed removal of large amount of Windows-specific OCaml and mainly C code.

Changes in 2.52.1

Released 2022-05-08

• Deprecate ocaml < 4.08: 2.53.0 will require 4.08 or higher
• Add man page
• Remove rsh:// URI scheme (ssh:// of course remains).
• Significant bugfixes and minor improvements
• Deprecate "backups" preference (see manual for alternatives)
• Deprecate "stream" and "halfduplex" preferences

Changes in 2.52.0

Released 2022-03-12

• Feature negotiation, compatible with 2.51.
• New archive format (independent of ocaml version, based on umarshal) Upgrade is automatic.
• New wire protocol (independent of ocaml version, based on umarshal) New protocol is used if both sides are >= 2.52.0.
• Compatibility with 2.48
• Support for unix-domain sockets
• Many bugfixes and minor improvements
• ocaml compatibility is now >= 4.01
• NEWS is now in NEWS.md and not in the manual

Changes in 2.51.5

Released 2021-12-18

 * Restore OCaml compat to before 4.02
 * dune/opam improvements/fixes
 * Improve GTK UI by using GtkTreeView
 * Add support for syncing symlinks on Windows (NTFS)
 * Improve ssh support on Windows (hide Windows console in GUI mode)
 * Many bugfixes and minor improvements

Changes in 2.51.4

Released 2021-06-24

 * OCaml 4.12 support
 * fsmonitor improvements and Solaris support
 * Color support in text UI, with a new preference, disabled by
   NO_COLOR.
 * Interactive profile selection in text UI, enabled by a new
   preference.
 * Working files are stored in the unison directory (typically
   /.unison) rather than $HOME.
 * Build cleanups, CI improvements, housekeeping
 * Many bugfixes and minor improvements

Changes in 2.51.3

Released 2020-10-21

 * Some nontrivial changes to profile parsing (G.raud Meyer)
      + '=' has been considered whitespace until now: several
        following chars are considered as only one; trailing chars are
        discarded; any non empty sequence of char is splitting. This
        is non standard and leads to confusion, for example -ignore==
        'Name .*=*' is valid when -ignore='Name .*=*' is not, and
        worse -ignore='Name *=' is the same as -ignore='Name *'. The
        parser now takes just a single '=' as delimiter after the
        option name. Other = characters are considered as part of the
        value being assigned to the option.
 * Numerous improvements to the text user-interface (G.raud Meyer)
      + New key-commands that restrict the display to a set of
        "matching" items: ones that are offering to propagate changes
        in a particular direction, conflicts, files to be merged,
        etc., plus several more useful key-commands. Type "?" to
        Unison to see all available commands.

Changes in 2.51.0 through 2.51.2

 * Repository transplanted from SVN to Git and moved to GitHub ()
   (https://github.com/bcpierce00/unison).
 * Add a new preference, 'atomic', for specifying directories that
   should be treated atomically: if there are changes within such a
   directory in both replicase, the whole directory is marked as a
   conflict instead of propagating any of the changes. Thanks to
   Julian Squires for submitting this patch!
 * OSX / macOS
      + Ported to 10.13, High Sierra, and Apple's new APFS (earlier
        versions of Unison break because of new behavior of
        AppleDouble files)
      + Replaced Growl with OS X native notification center.
 * Miscellaneous:
      + The OCaml compiler version is now included in the "connection
        header -- the string that's printed when connecting to a
        remote server -- to facilitate debugging version mismatch
        issues.
      + Compatible with OCaml 4.06.
      + Added a DockerFile for the convenience of Docker users.
      + Many small bugfixes and UI improvements.

Changes in 2.48

 * Incorporated a patch from Christopher Zimmermann to replace the
   Uprintf module (which doesn't work with OCaml 4.02, causing Unison
   to crash) with equivalent functionality from the standard library.
 * Incorporated a refresh of the OSX GUI, contributed by Alan Shutko.
 * Added a maxsizethreshold option, which prevents the transfer of
   files larger than the size specified (in Kb).
 * Added a "copyonconflict" preference, to make a copy of files that
   would otherwise be overwritten or deleted in case of conflicting
   changes. (This makes it possible to automatically resolve conflicts
   in a fairly safe way when synchronizing continuously, in
   combination with the "repeat = watch" and "prefer = newer"
   preferences.
 * File system monitoring:
      + The file watcher now fails when unable to watch a directory,
        rather than silently ignoring the issue.
      + File system monitoring: more robust communication with the
        helper program (in socket mode, the unison server will still
        work properly despite unexpected unison client
        disconnections).
      + A bytecode version of unison-fsmonitor is now produced by
        "make NATIVE=false"
      + Improved search for unison-fsmonitor
      + Detect when the helper process exits.
      + More robust file watching helper programs for Windows and
        Linux. They communicate with Unison through pipes (Unison
        redirects stdin and stdout), using a race-free protocol.
      + Retries paths with failures using an exponential backoff
        algorithm.
      + The information returned by the file watchers are used
        independently for each replica; thus, when only one replica
        has changes, Unison will only rescan this replica.
      + When available, used by the graphical UIs to speed up
        rescanning (can be disabled by setting the new watch
        preference to
      + Small fix to the way fsmonitor.py gets invoked when using the
        file watching functionality, suggested by Josh Berdine. Unison
        will now look for fsmonitor.py in the same directory where the
        Unison executable itself lives.
 * Minor:
      + Fixed a bug in export procedure that was messing up
        documentation strings.
      + Incorporated a patch from Irányossy Knoblauch Artúr to make
        temp file names fit within 143 characters (to make eCryptFS
        happy).
      + Added a string to the Conflict direction to document the
        reason of the conflict.
      + Log conflicts and problems in the text UI even if nothing is
        propagated.
      + Use hash function from OCaml 3.x for comparing archives, even
        when compiled with OCaml 4.x.
      + Do not restart Unison in case of uncaught exception when the
        repeat preference is set. This seems safer. And it does not
        work, for instance, in case of lost connection.
      + Fix Unix.readlink invalid argument error under Windows
      + Fix a crash when the output of the diff program is too large.
      + Fixed Makefile for cross-compiling towards Windows (updated to
        MinGW-w64)

Changes in very old versions

(Note that these are written 'Changes since' and thus the content applies to the release after that.)

Changes since 2.40.63: * New preference fastercheckUNSAFE, which can be used (with care!) to achieve much faster update detection when all the common files in the two replicas are known to be identical. See the manual for more information. This feature should still be considered experimental, but it's ready for other people to try out. * Added option clientHostName. If specified, it will be used to as the client host name, overriding UNISONLOCALHOSTNAME and the actual host name. * OS X GUI: + fix crash under Lion, because of problems with the toolbar, using the fix suggested in http://blitzbasic.com/Community/posts.php?topic=95778. + uimacnew09 is now the standard graphical interface on OSX + A small improvement to the uimacnew09 interface from Alan Schmitt and Steve Kalkwarf: when Unison is run with the -batch flag, the interface will now automatically propagate changes and terminate, without waiting for user interaction. + Show a modal warning window if there is no archive for the hosts. The user can then choose to exit or proceed (proceed is the default). The window is not shown if the batch preference is true. + file details panel selectable * GTK GUI: + New version of uigtk2.ml from Matt Zagrabelny that reorganizes the icons in a slightly more intuitive way. * Minor fixes: + Setting the prefer preference to older or newer now propagates deletions when there is no conflict. + Correctly quote the path when running merge commands. + Add quotes to paths when calling external file watcher utility. + Incorporate a patch to fsmonitor.py (the external filewatcher utility) from Tomasz Zernicki to make it work better under Windows. + Incorporated new version of fsmonitor.py from Christophe Gohle + Fixed incompatibility with OpenSSH 5.6. + Fixed fingerprint cache: do not cache file properties + Some spelling corrections in documentation and comments from Stephane Glondu + Fixed O_APPEND mode for open under Windows + Fixed String.sub invalid argument error when an AppleDouble file does not contain a finder information field + Trim duplicate paths when using "-repeat watch" + Unison now passes path arguments and -follow directives to fsmonitor.py. This seems to work except for one small issue with how fsmonitor.py treats -follow directives for directories that don't exist (or maybe this is an issue with how it treats any kind of monitoring when the thing being monitored doesn't exist?). If we create a symlink to a nonexistent directory, give Unison (hence fsmonitor.py) a 'follow' directive for the symlink, start unison, and then create the directory, fsmonitor.py misses the change. + Lines added in profile files by unison always start at a new line

Changes since 2.40.1: * Added "BelowPath" patterns, that match a path as well as all paths below (convenient to use with nodeletion,update,creationpartial preferences) * Added a "fat" preference that makes Unison use the right options when one of the replica is on a FAT filesystem. * Allow "prefer/force=newer" even when not synchronizing modification times. (The reconciler will not be aware of the modification time of unchanged files, so the synchronization choices of Unison can be different from when "times=true", but the behavior remains sane: changed files with the most recent modification time will be propagated.) * Minor fixes and improvements: + Compare filenames up to decomposition in case sensitive mode when one host is running MacOSX and the unicode preference is set to true. + Rsync: somewhat faster compressor + Make Unicode the default on all architectures (it was only the default when a Mac OS X or Windows machine was involved).

Changes since 2.32: * Major enhancement: Unicode support. + Unison should now handle unicode filenames correctly on all platforms. + This functionality is controlled by a new preference unicode. + Unicode mode is now the default when one of the hosts is under Windows or MacOS. This may make upgrades a bit more painful (the archives cannot be reused), but this is a much saner default. * Partial transfer of directories. If an error occurs while transferring a directory, the part transferred so far is copied into place (and the archives are updated accordingly). The "maxerrors" preference controls how many transfer error Unison will accept before stopping the transfer of a directory (by default, only one). This makes it possible to transfer most of a directory even if there are some errors. Currently, only the first error is reported by the GUIs. Also, allow partial transfer of a directory when there was an error deep inside this directory during update detection. At the moment, this is only activated with the text and GTK UIs, which have been modified so that they show that the transfer is going to be partial and so that they can display all errors. * Improvement to the code for resuming directory transfers: + if a file was not correctly transferred (or the source has been modified since, with unchanged size), Unison performs a new transfer rather than failing + spurious files are deleted (this can happen if a file is deleted on the source replica before resuming the transfer; not deleting the file would result in it reappearing on the target replica) * Experimental streaming protocol for transferring file contents (can be disabled by setting the directive "stream" to false): file contents is transferred asynchronously (without waiting for a response from the destination after each chunk sent) rather than using the synchronous RPC mechanism. As a consequence: + Unison now transfers the contents of a single file at a time (Unison used to transfer several contents simultaneously in order to hide the connection latency.) + the transfer of large files uses the full available bandwidth and is not slowed done due to the connection latency anymore + we get performance improvement for small files as well by scheduling many files simultaneously (as scheduling a file for transfer consume little resource: it does not mean allocating a large buffer anymore) * Changes to the internal implementation of the rsync algorithm: + use longer blocks for large files (the size of a block is the square root of the size of the file for large files); + transmit less checksum information per block (we still have less than one chance in a hundred million of transferring a file incorrectly, and Unison will catch any transfer error when fingerprinting the whole file) + avoid transfer overhead (which was 4 bytes per block) For a 1G file, the first optimization saves a factor 50 on the amount of data transferred from the target to the source (blocks are 32768 bytes rather than just 700 bytes). The two other optimizations save another factor of 2 (from 24 bytes per block down to 10). * Implemented an on-disk file fingerprint cache to speed-up update detection after a crash: this way, Unison does not have do recompute all the file fingerprints from scratch. + When Unison detects that the archive case-sensitivity mode does not match the current settings, it populates the fingerprint cache using the archive contents. This way, changing the case-sensitivity mode should be reasonably fast. * New preferences "noupdate=root", "nodeletion=root", "nocreation=root" that prevent Unison from performing files updates, deletions or creations on the given root. Also 'partial' versions of 'noupdate', 'nodeletion' and 'nocreation' * Limit the number of simultaneous external copy program ("copymax" preference) * New "links" preference. When set to false, Unison will report an error on symlinks during update detection. (This is the default when one host is running Windows but not Cygwin.) This is better than failing during propagation. * Added a preference "halfduplex" to force half-duplex communication with the server. This may be useful on unreliable links (as a more efficient alternative to "maxthreads = 1"). * Renamed preference "pretendwin" to "ignoreinodenumbers" (an alias is kept for backwards compatibility). * Ignore one-second differences when synchronizing modification time. (Technically, this is an incompatible archive format change, but it is backward compatible. To trigger a problem, a user would have to synchronize modification times on a filesystem with a two-second granularity and then downgrade to a previous version of Unison, which does not work well in such a case. Thus, it does not seem worthwhile to increment the archive format number, which would impact all users.) * Do not keep many files simultaneously opened anymore when the rsync algorithm is in use. * Add "ignorearchives" preference to ignore existing archives (to avoid forcing users to delete them manually, in situations where one archive has gotten deleted or corrupted). * Mac OS + fixed rsync bug which could result in an "index out of bounds" error when transferring resource forks. + Fixed bug which made Unison ignore finder information and resource fork when compiled to 64bit on Mac OSX. + should now be 64 bit clean (the Growl framework is not up to date, though) + Made the bridge between Objective C and Ocaml code GC friendly (it was allocating ML values and putting them in an array which was not registered with the GC) + use darker grey arrows (patch contributed by Eric Y. Kow) * GTK user interface + assistant for creating profiles + profile editor + pop up a summary window when the replicas are not fully synchronized after transport + display estimated remaining time and transfer rate on the progress bar + allow simultaneous selection of several items + Do not reload the preference file before a new update detection if it is unchanged + disabled scrolling to the first unfinished item during transport. It goes way too fast when lot of small files are synchronized, and it makes it impossible to browse the file list during transport. + take into account the "height" preference again + the internal list of selected reconciler item was not always in sync with what was displayed (GTK bug?); workaround implemented + Do not display "Looking for change" messages during propagation (when checking the targe is unchanged) but only during update detection + Apply patch to fix some crashes in the OSX GUI, thanks to Onne Gorter. * Text UI + During update detection, display status by updating a single line rather than generating a new line of output every so often. Should be less confusing. * Windows + Fastcheck is now the default under Windows. People mostly use NTFS nowadays and the Unicode API provides an equivalent to inode numbers for this filesystem. + Only use long UNC path for accessing replicas (as '..' is not handled with this format of paths, but can be useful) + Windows text UI: now put the console into UTF-8 output mode. This is the right thing to do when in Unicode mode, and is no worse than what we had previously otherwise (the console use some esoteric encoding by default). This only works when using a Unicode font instead of the default raster font. + Don't get the home directory from environment variable HOME under Windows (except for Cygwin binaries): we don't want the behavior of Unison to depends on whether it is run from a Cygwin shell (where HOME is set) or in any other way (where HOME is usually not set). * Miscellaneous fixes and improvements + Made a server waiting on a socket more resilient to unexpected lost connections from the client. + Small patch to property setting code suggested by Ulrich Gernkow. + Several fixes to the change transfer functions (both the internal ones and external transfers using rsync). In particular, limit the number of simultaneous transfer using an rsync (as the rsync algorithm can use a large amount of memory when processing huge files) + Keep track of which file contents are being transferred, and delay the transfer of a file when another file with the same contents is currently being transferred. This way, the second transfer can be skipped and replaced by a local copy. + Experimental update detection optimization: do not read the contents of unchanged directories + When a file transfer fails, turn off fastcheck for this file on the next sync. + Fixed bug with case insensitive mode on a case sensitive filesystem: o if file "a/a" is created on one replica and directory "A" is created on the other, the file failed to be synchronized the first time Unison is run afterwards, as Unison uses the wrong path "a/a" (if Unison is run again, the directories are in the archive, so the right path is used); o if file "a" appears on one replica and file "A" appears on the other with different contents, Unison was unable to synchronize them. + Improved error reporting when the destination is updated during synchronization: Unison now tells which file has been updated, and how. + Limit the length of temporary file names + Case sensitivity information put in the archive (in a backward compatible way) and checked when the archive is loaded + Got rid of the 16mb marshalling limit by marshalling to a bigarray. + Resume copy of partially transferred files.

Changes since 2.31: * Small user interface changes + Small change to text UI "scanning..." messages, to print just directories (hopefully making it clearer that individual files are not necessarily being fingerprinted). * Minor fixes and improvements: + Ignore one hour differences when deciding whether a file may have been updated. This avoids slow update detection after daylight saving time changes under Windows. This makes Unison slightly more likely to miss an update, but it should be safe enough. + Fix a small bug that was affecting mainly windows users. We need to commit the archives at the end of the sync even if there are no updates to propagate because some files (in fact, if we've just switched to DST on windows, a LOT of files) might have new modtimes in the archive. (Changed the text UI only. It's less clear where to change the GUI.) + Don't delete the temp file when a transfer fails due to a fingerprint mismatch (so that we can have a look and see why!) We've also added more debugging code togive more informative error messages when we encounter the dreaded and longstanding "assert failed during file transfer" bug + Incorrect paths ("path" directive) now result in an error update item rather than a fatal error. + Create parent directories (with correct permissions) during transport for paths which point to non-existent locations in the destination replica.

Changes since 2.27: * If Unison is interrupted during a directory transfer, it will now leave the partially transferred directory intact in a temporary location. (This maintains the invariant that new files/directories are transferred either completely or not at all.) The next time Unison is run, it will continue filling in this temporary directory, skipping transferring files that it finds are already there. * We've added experimental support for invoking an external file transfer tool for whole-file copies instead of Unison's built-in transfer protocol. Three new preferences have been added: + copyprog is a string giving the name (and command-line switches, if needed) of an external program that can be used to copy large files efficiently. By default, rsync is invoked, but other tools such as scp can be used instead by changing the value of this preference. (Although this is not its primary purpose, rsync is actually a pretty fast way of copying files that don't already exist on the receiving host.) For files that do already exist on (but that have been changed in one replica), Unison will always use its built-in implementation of the rsync algorithm. + Added a "copyprogrest" preference, so that we can give different command lines for invoking the external copy utility depending on whether a partially transferred file already exists or not. (Rsync doesn't seem to care about this, but other utilities may.) + copythreshold is an integer (-1 by default), indicating above what filesize (in megabytes) Unison should use the external copying utility specified by copyprog. Specifying 0 will cause ALL copies to use the external program; a negative number will prevent any files from using it. (Default is -1.) Thanks to Alan Schmitt for a huge amount of hacking and to an anonymous sponsor for suggesting and underwriting this extension. * Small improvements: + Added a new preference, dontchmod. By default, Unison uses the chmod system call to set the permission bits of files after it has copied them. But in some circumstances (and under some operating systems), the chmod call always fails. Setting this preference completely prevents Unison from ever calling chmod. + Don't ignore files that look like backup files if the backuplocation preference is set to central + Shortened the names of several preferences. The old names are also still supported, for backwards compatibility, but they do not appear in the documentation. + Lots of little documentation tidying. (In particular, preferences are separated into Basic and Advanced! This should hopefully make Unison a little more approachable for new users. + Unison can sometimes fail to transfer a file, giving the unhelpful message "Destination updated during synchronization" even though the file has not been changed. This can be caused by programs that change either the file's contents or the file's extended attributes without changing its modification time. It's not clear what is the best fix for this - it is not Unison's fault, but it makes Unison's behavior puzzling - but at least Unison can be more helpful about suggesting a workaround (running once with fastcheck set to false). The failure message has been changed to give this advice. + Further improvements to the OS X GUI (thanks to Alan Schmitt and Craig Federighi). * Very preliminary support for triggering Unison from an external filesystem-watching utility. The current implementation is very simple, not efficient, and almost completely untested--not ready for real users. But if someone wants to help improve it (e.g., by writing a filesystem watcher for your favorite OS), please make yourself known! On the Unison side, the new behavior is very simple: + use the text UI + start Unison with the command-line flag "-repeat FOO", where FOO is name of a file where Unison should look for notifications of changes + when it starts up, Unison will read the whole contents of this file (on both hosts), which should be a newline-separated list of paths (relative to the root of the synchronization) and synchronize just these paths, as if it had been started with the "-path=xxx" option for each one of them + when it finishes, it will sleep for a few seconds and then examine the watchfile again; if anything has been added, it will read the new paths, synchronize them, and go back to sleep + that's it! To use this to drive Unison "incrementally," just start it in this mode and start up a tool (on each host) to watch for new changes to the filesystem and append the appropriate paths to the watchfile. Hopefully such tools should not be too hard to write. * Bug fixes: + Fixed a bug that was causing new files to be created with permissions 0x600 instead of using a reasonable default (like 0x644), if the 'perms' flag was set to 0. (Bug reported by Ben Crowell.) + Follow maxthreads preference when transferring directories.

Changes since 2.17: * Major rewrite and cleanup of the whole Mac OS X graphical user interface by Craig Federighi. Thanks, Craig!!! * Small fix to ctime (non-)handling in update detection under windows with fastcheck. * Several small fixes to the GTK2 UI to make it work better under Windows [thanks to Karl M for these]. * The backup functionality has been completely rewritten. The external interface has not changed, but numerous bugs, irregular behaviors, and cross-platform inconsistencies have been corrected. * The Unison project now accepts donations via PayPal. If you'd like to donate, you can find a link to the donation page on the Unison home page (http://www.cis.upenn.edu/ bcpierce/unison/lists.html). * Some important safety improvements: + Added a new mountpoint preference, which can be used to specify a path that must exist in both replicas at the end of update detection (otherwise Unison aborts). This can be used to avoid potentially dangerous situations when Unison is used with removable media such as external hard drives and compact flash cards. + The confirmation of "big deletes" is now controlled by a boolean preference confirmbigdeletes. Default is true, which gives the same behavior as previously. (This functionality is at least partly superseded by the mountpoint preference, but it has been left in place in case it is useful to some people.) + If Unison is asked to "follow" a symbolic link but there is nothing at the other end of the link, it will now flag this path as an error, rather than treating the symlink itself as missing or deleted. This avoids a potentially dangerous situation where a followed symlink points to an external filesystem that might be offline when Unison is run (whereupon Unison would cheerfully delete the corresponding files in the other replica!). * Smaller changes: + Added forcepartial and preferpartial preferences, which behave like force and prefer but can be specified on a per-path basis. [Thanks to Alan Schmitt for this.] + A bare-bones self test feature was added, which runs unison through some of its paces and checks that the results are as expected. The coverage of the tests is still very limited, but the facility has already been very useful in debugging the new backup functionality (especially in exposing some subtle cross-platform issues). + Refined debugging code so that the verbosity of individual modules can be controlled separately. Instead of just putting '-debug verbose' on the command line, you can put '-debug update+', which causes all the extra messages in the Update module, but not other modules, to be printed. Putting '-debug verbose' causes all modules to print with maximum verbosity. + Removed mergebatch preference. (It never seemed very useful, and its semantics were confusing.) + Rewrote some of the merging functionality, for better cooperation with external Harmony instances. + Changed the temp file prefix from .# to .unison. + Compressed the output from the text user interface (particularly when run with the -terse flag) to make it easier to interpret the results when Unison is run several times in succession from a script. + Diff and merge functions now work under Windows. + Changed the order of arguments to the default diff command (so that the + and - annotations in diff's output are reversed). + Added .mpp files to the "never fastcheck" list (like .xls files). * Many small bugfixes, including: + Fixed a longstanding bug regarding fastcheck and daylight saving time under Windows when Unison is set up to synchronize modification times. (Modification times cannot be updated in the archive in this case, so we have to ignore one hour differences.) + Fixed a bug that would occasionally cause the archives to be left in non-identical states on the two hosts after synchronization. + Fixed a bug that prevented Unison from communicating correctly between 32- and 64-bit architectures. + On windows, file creation times are no longer used as a proxy for inode numbers. (This is unfortunate, as it makes fastcheck a little less safe. But it turns out that file creation times are not reliable under Windows: if a file is removed and a new file is created in its place, the new one will sometimes be given the same creation date as the old one!) + Set read-only file to R/W on OSX before attempting to change other attributes. + Fixed bug resulting in spurious "Aborted" errors during transport (thanks to Jerome Vouillon) + Enable diff if file contents have changed in one replica, but only properties in the other. + Removed misleading documentation for 'repeat' preference. + Fixed a bug in merging code where Unison could sometimes deadlock with the external merge program, if the latter produced large amounts of output. + Workaround for a bug compiling gtk2 user interface against current versions of gtk2+ libraries. + Added a better error message for "ambiguous paths". + Squashed a longstanding bug that would cause file transfer to fail with the message "Failed: Error in readWrite: Is a directory." + Replaced symlinks with copies of their targets in the Growl framework in src/uimac. This should make the sources easier to check out from the svn repository on WinXP systems. + Added a workaround (suggested by Karl M.) for the problem discussed on the unison users mailing list where, on the Windows platform, the server would hang when transferring files. I conjecture that the problem has to do with the RPC mechanism, which was used to make a call back from the server to the client (inside the Trace.log function) so that the log message would be appended to the log file on the client. The workaround is to dump these messages (about when xferbycopying shortcuts are applied and whether they succeed) just to the standard output of the Unison process, not to the log file.

Changes since 2.13.0: * The features for performing backups and for invoking external merge programs have been completely rewritten by Stephane Lescuyer (thanks, Stephane!). The user-visible functionality should not change, but the internals have been rationalized and there are a number of new features. See the manual (in particular, the description of the backupXXX preferences) for details. * Incorporated patches for ipv6 support, contributed by Samuel Thibault. (Note that, due to a bug in the released OCaml 3.08.3 compiler, this code will not actually work with ipv6 unless compiled with the CVS version of the OCaml compiler, where the bug has been fixed; however, ipv4 should continue to work normally.) * OSX interface: + Incorporated Ben Willmore's cool new icon for the Mac UI. * Small fixes: + Fixed off by one error in month numbers (in printed dates) reported by Bob Burger

Changes since 2.12.0: * New convention for release numbering: Releases will continue to be given numbers of the form X.Y.Z, but, from now on, just the major version number (X.Y) will be considered significant when checking compatibility between client and server versions. The third component of the version number will be used only to identify "patch levels" of releases. This change goes hand in hand with a change to the procedure for making new releases. Candidate releases will initially be given "beta release" status when they are announced for public consumption. Any bugs that are discovered will be fixed in a separate branch of the source repository (without changing the major version number) and new tarballs re-released as needed. When this process converges, the patched beta version will be dubbed stable. * Warning (failure in batch mode) when one path is completely emptied. This prevents Unison from deleting everything on one replica when the other disappear. * Fix diff bug (where no difference is shown the first time the diff command is given). * User interface changes: + Improved workaround for button focus problem (GTK2 UI) + Put leading zeroes in date fields + More robust handling of character encodings in GTK2 UI + Changed format of modification time displays, from modified at hh:mm:ss on dd MMM, yyyy to modified on yyyy-mm-dd hh:mm:ss + Changed time display to include seconds (so that people on FAT filesystems will not be confused when Unison tries to update a file time to an odd number of seconds and the filesystem truncates it to an even number!) + Use the diff "-u" option by default when showing differences between files (the output is more readable) + In text mode, pipe the diff output to a pager if the environment variable PAGER is set + Bug fixes and cleanups in ssh password prompting. Now works with the GTK2 UI under Linux. (Hopefully the Mac OS X one is not broken!) + Include profile name in the GTK2 window name + Added bindings ',' (same as '<') and '.' (same as '>') in the GTK2 UI * Mac GUI: + actions like < and > scroll to the next item as necessary. + Restart has a menu item and keyboard shortcut (command-R). + Added a command-line tool for Mac OS X. It can be installed from the Unison menu. + New icon. + Handle the "help" command-line argument properly. + Handle profiles given on the command line properly. + When a profile has been selected, the profile dialog is replaced by a "connecting" message while the connection is being made. This gives better feedback. + Size of left and right columns is now large enough so that "PropsChanged" is not cut off. * Minor changes: + Disable multi-threading when both roots are local + Improved error handling code. In particular, make sure all files are closed in case of a transient failure + Under Windows, use $UNISON for home directory as a last resort (it was wrongly moved before $HOME and $USERPROFILE in Unison 2.12.0) + Reopen the logfile if its name changes (profile change) + Double-check that permissions and modification times have been properly set: there are some combination of OS and filesystem on which setting them can fail in a silent way. + Check for bad Windows filenames for pure Windows synchronization also (not just cross architecture synchronization). This way, filenames containing backslashes, which are not correctly handled by unison, are rejected right away. + Attempt to resolve issues with synchronizing modification times of read-only files under Windows + Ignore chmod failures when deleting files + Ignore trailing dots in filenames in case insensitive mode + Proper quoting of paths, files and extensions ignored using the UI + The strings CURRENT1 and CURRENT2 are now correctly substituted when they occur in the diff preference + Improvements to syncing resource forks between Macs via a non-Mac system.

Changes since 2.10.2: * INCOMPATIBLE CHANGE: Archive format has changed. * Source code availability: The Unison sources are now managed using Subversion. One nice side-effect is that anonymous checkout is now possible, like this: svn co https://cvs.cis.upenn.edu:3690/svnroot/unison/

   We will also continue to export a "developer tarball" of the
   current (modulo one day) sources in the web export directory. To
   receive commit logs for changes to the sources, subscribe to the
   unison-hackers list (http://www.cis.upenn.edu/
   bcpierce/unison/lists.html).
 * Text user interface:
      + Substantial reworking of the internal logic of the text UI to
        make it a bit easier to modify.
      + The dumbtty flag in the text UI is automatically set to true
        if the client is running on a Unix system and the EMACS
        environment variable is set to anything other than the empty
        string.
 * Native OS X gui:
      + Added a synchronize menu item with keyboard shortcut
      + Added a merge menu item, still needs to be debugged
      + Fixes to compile for Panther
      + Miscellaneous improvements and bugfixes
 * Small changes:
      + Changed the filename checking code to apply to Windows only,
        instead of OS X as well.
      + Finder flags now synchronized
      + Fallback in copy.ml for filesystem that do not support O_EXCL
      + Changed buffer size for local file copy (was highly
        inefficient with synchronous writes)
      + Ignore chmod failure when deleting a directory
      + Fixed assertion failure when resolving a conflict content
        change / permission changes in favor of the content change.
      + Workaround for transferring large files using rsync.
      + Use buffered I/O for files (this is the only way to open files
        in binary mode under Cygwin).
      + On non-Cygwin Windows systems, the UNISON environment variable
        is now checked first to determine where to look for Unison's
        archive and preference files, followed by HOME and USERPROFILE
        in that order. On Unix and Cygwin systems, HOME is used.
      + Generalized diff preference so that it can be given either as
        just the command name to be used for calculating diffs or else
        a whole command line, containing the strings CURRENT1 and
        CURRENT2, which will be replaced by the names of the files to
        be diff'ed before the command is called.
      + Recognize password prompts in some newer versions of ssh.

Changes since 2.9.20: * INCOMPATIBLE CHANGE: Archive format has changed. * Major functionality changes: + Major tidying and enhancement of 'merge' functionality. The main user-visible change is that the external merge program may either write the merged output to a single new file, as before, or it may modify one or both of its input files, or it may write two new files. In the latter cases, its modifications will be copied back into place on both the local and the remote host, and (if the two files are now equal) the archive will be updated appropriately. More information can be found in the user manual. Thanks to Malo Denielou and Alan Schmitt for these improvements. Warning: the new merging functionality is not completely compatible with old versions! Check the manual for details. + Files larger than 2Gb are now supported. + Added preliminary (and still somewhat experimental) support for the Apple OS X operating system. o Resource forks should be transferred correctly. (See the manual for details of how this works when synchronizing HFS with non-HFS volumes.) Synchronization of file type and creator information is also supported. o On OSX systems, the name of the directory for storing Unison's archives, preference files, etc., is now determined as follows: # if ~/.unison exists, use it # otherwise, use ~/Library/Application Support/Unison, creating it if necessary. o A preliminary native-Cocoa user interface is under construction. This still needs some work, and some users experience unpredictable crashes, so it is only for hackers for now. Run make with UISTYLE=mac to build this interface. * Minor functionality changes: + Added an ignorelocks preference, which forces Unison to override left-over archive locks. (Setting this preference is dangerous! Use it only if you are positive you know what you are doing.) + Added a new preference assumeContentsAreImmutable. If a directory matches one of the patterns set in this preference, then update detection is skipped for files in this directory. (The purpose is to speed update detection for cases like Mail folders, which contain lots and lots of immutable files.) Also a preference assumeContentsAreImmutableNot, which overrides the first, similarly to ignorenot. (Later amendment: these preferences are now called immutable and immutablenot.) + The ignorecase flag has been changed from a boolean to a three-valued preference. The default setting, called default, checks the operating systems running on the client and server and ignores filename case if either of them is OSX or Windows. Setting ignorecase to true or false overrides this behavior. If you have been setting ignorecase on the command line using -ignorecase=true or -ignorecase=false, you will need to change to -ignorecase true or -ignorecase false. + a new preference, 'repeat', for the text user interface (only). If 'repeat' is set to a number, then, after it finishes synchronizing, Unison will wait for that many seconds and then start over, continuing this way until it is killed from outside. Setting repeat to true will automatically set the batch preference to true. + Excel files are now handled specially, so that the fastcheck optimization is skipped even if the fastcheck flag is set. (Excel does some naughty things with modtimes, making this optimization unreliable and leading to failures during change propagation.) + The ignorecase flag has been changed from a boolean to a three-valued preference. The default setting, called 'default', checks the operating systems running on the client and server and ignores filename case if either of them is OSX or Windows. Setting ignorecase to 'true' or 'false' overrides this behavior. + Added a new preference, 'repeat', for the text user interface (only, at the moment). If 'repeat' is set to a number, then, after it finishes synchronizing, Unison will wait for that many seconds and then start over, continuing this way until it is killed from outside. Setting repeat to true will automatically set the batch preference to true. + The 'rshargs' preference has been split into 'rshargs' and 'sshargs' (mainly to make the documentation clearer). In fact, 'rshargs' is no longer mentioned in the documentation at all, since pretty much everybody uses ssh now anyway. * Documentation + The web pages have been completely redesigned and reorganized. (Thanks to Alan Schmitt for help with this.) * User interface improvements + Added a GTK2 user interface, capable (among other things) of displaying filenames in any locale encoding. Kudos to Stephen Tse for contributing this code! + The text UI now prints a list of failed and skipped transfers at the end of synchronization. + Restarting update detection from the graphical UI will reload the current profile (which in particular will reset the -path preference, in case it has been narrowed by using the "Recheck unsynchronized items" command). + Several small improvements to the text user interface, including a progress display. * Bug fixes (too numerous to count, actually, but here are some): + The maxthreads preference works now. + Fixed bug where warning message about uname returning an unrecognized result was preventing connection to server. (The warning is no longer printed, and all systems where 'uname' returns anything other than 'Darwin' are assumed not to be running OS X.) + Fixed a problem on OS X that caused some valid file names (e.g., those including colons) to be considered invalid. + Patched Path.followLink to follow links under cygwin in addition to Unix (suggested by Matt Swift). + Small change to the storeRootsName function, suggested by bliviero at ichips.intel.com, to fix a problem in unison with the `rootalias' option, which allows you to tell unison that two roots contain the same files. Rootalias was being applied after the hosts were sorted, so it wouldn't work properly in all cases. + Incorporated a fix by Dmitry Bely for setting utimes of read-only files on Win32 systems. * Installation / portability: + Unison now compiles with OCaml version 3.07 and later out of the box. + Makefile.OCaml fixed to compile out of the box under OpenBSD. + a few additional ports (e.g. OpenBSD, Zaurus/IPAQ) are now mentioned in the documentation + Unison can now be installed easily on OSX systems using the Fink package manager

Changes since 2.9.1: * Added a preference maxthreads that can be used to limit the number of simultaneous file transfers. * Added a backupdir preference, which controls where backup files are stored. * Basic support added for OSX. In particular, Unison now recognizes when one of the hosts being synchronized is running OSX and switches to a case-insensitive treatment of filenames (i.e., 'foo' and 'FOO' are considered to be the same file). (OSX is not yet fully working, however: in particular, files with resource forks will not be synchronized correctly.) * The same hash used to form the archive name is now also added to the names of the temp files created during file transfer. The reason for this is that, during update detection, we are going to silently delete any old temp files that we find along the way, and we want to prevent ourselves from deleting temp files belonging to other instances of Unison that may be running in parallel, e.g. synchronizing with a different host. Thanks to Ruslan Ermilov for this suggestion. * Several small user interface improvements * Documentation + FAQ and bug reporting instructions have been split out as separate HTML pages, accessible directly from the unison web page. + Additions to FAQ, in particular suggestions about performance tuning. * Makefile + Makefile.OCaml now sets UISTYLE=text or UISTYLE=gtk automatically, depending on whether it finds lablgtk installed + Unison should now compile "out of the box" under OSX

Changes since 2.8.1: * Changing profile works again under Windows * File movement optimization: Unison now tries to use local copy instead of transfer for moved or copied files. It is controlled by a boolean option "xferbycopying". * Network statistics window (transfer rate, amount of data transferred). [NB: not available in Windows-Cygwin version.] * symlinks work under the cygwin version (which is dynamically linked). * Fixed potential deadlock when synchronizing between Windows and Unix * Small improvements: + If neither the USERPROFILE nor the HOME environment variables are set, then Unison will put its temporary commit log (called DANGER.README) into the directory named by the UNISON environment variable, if any; otherwise it will use C:. + alternative set of values for fastcheck: yes = true; no = false; default = auto. + -silent implies -contactquietly * Source code: + Code reorganization and tidying. (Started breaking up some of the basic utility modules so that the non-unison-specific stuff can be made available for other projects.) + several Makefile and docs changes (for release); + further comments in "update.ml"; + connection information is not stored in global variables anymore.

Changes since 2.7.78: * Small bugfix to textual user interface under Unix (to avoid leaving the terminal in a bad state where it would not echo inputs after Unison exited).

Changes since 2.7.39: * Improvements to the main web page (stable and beta version docs are now both accessible). * User manual revised. * Added some new preferences: + "sshcmd" and "rshcmd" for specifying paths to ssh and rsh programs. + "contactquietly" for suppressing the "contacting server" message during Unison startup (under the graphical UI). * Bug fixes: + Fixed small bug in UI that neglected to change the displayed column headers if loading a new profile caused the roots to change. + Fixed a bug that would put the text UI into an infinite loop if it encountered a conflict when run in batch mode. + Added some code to try to fix the display of non-Ascii characters in filenames on Windows systems in the GTK UI. (This code is currently untested--if you're one of the people that had reported problems with display of non-ascii filenames, we'd appreciate knowing if this actually fixes things.) + -prefer/-force newer' works properly now. (The bug was reported by Sebastian Urbaniak and Sean Fulton.) * User interface and Unison behavior: + Renamed Proceed' to `Go' in the graphical UI. + Added exit status for the textual user interface. + Paths that are not synchronized because of conflicts or errors during update detection are now noted in the log file. + [END] messages in log now use a briefer format + Changed the text UI startup sequence so that ./unison -ui text will use the default profile instead of failing. + Made some improvements to the error messages. + Added some debugging messages to remote.ml.

Changes since 2.7.7: * Incorporated, once again, a multi-threaded transport sub-system. It transfers several files at the same time, thereby making much more effective use of available network bandwidth. Unlike the earlier attempt, this time we do not rely on the native thread library of OCaml. Instead, we implement a light-weight, non-preemptive multi-thread library in OCaml directly. This version appears stable. Some adjustments to unison are made to accommodate the multi-threaded version. These include, in particular, changes to the user interface and logging, for example: + Two log entries for each transferring task, one for the beginning, one for the end. + Suppressed warning messages against removing temp files left by a previous unison run, because warning does not work nicely under multi-threading. The temp file names are made less likely to coincide with the name of a file created by the user. They take the form .#..unison.tmp. [N.b. This was later changed to .unison...unison.tmp.] * Added a new command to the GTK user interface: pressing 'f' causes Unison to start a new update detection phase, using as paths just those paths that have been detected as changed and not yet marked as successfully completed. Use this command to quickly restart Unison on just the set of paths still needing attention after a previous run. * Made the ignorecase preference user-visible, and changed the initialization code so that it can be manually set to true, even if neither host is running Windows. (This may be useful, e.g., when using Unison running on a Unix system with a FAT volume mounted.) * Small improvements and bug fixes: + Errors in preference files now generate fatal errors rather than warnings at startup time. (I.e., you can't go on from them.) Also, we fixed a bug that was preventing these warnings from appearing in the text UI, so some users who have been running (unsuspectingly) with garbage in their prefs files may now get error reports. + Error reporting for preference files now provides file name and line number. + More intelligible message in the case of identical change to the same files: "Nothing to do: replicas have been changed only in identical ways since last sync." + Files with prefix '.#' excluded when scanning for preference files. + Rsync instructions are send directly instead of first marshaled. + Won't try forever to get the fingerprint of a continuously changing file: unison will give up after certain number of retries. + Other bug fixes, including the one reported by Peter Selinger (force=older preference not working). * Compilation: + Upgraded to the new OCaml 3.04 compiler, with the LablGtk 1.2.3 library (patched version used for compiling under Windows). + Added the option to compile unison on the Windows platform with Cygwin GNU C compiler. This option only supports building dynamically linked unison executables.

Changes since 2.7.4: * Fixed a silly (but debilitating) bug in the client startup sequence.

Changes since 2.7.1: * Added addprefsto preference, which (when set) controls which preference file new preferences (e.g. new ignore patterns) are added to. * Bug fix: read the initial connection header one byte at a time, so that we don't block if the header is shorter than expected. (This bug did not affect normal operation -- it just made it hard to tell when you were trying to use Unison incorrectly with an old version of the server, since it would hang instead of giving an error message.)

Changes since 2.6.59: * Changed fastcheck from a boolean to a string preference. Its legal values are yes (for a fast check), no (for a safe check), or default (for a fast check--which also happens to be safe--when running on Unix and a safe check when on Windows). The default is default. * Several preferences have been renamed for consistency. All preference names are now spelled out in lowercase. For backward compatibility, the old names still work, but they are not mentioned in the manual any more. * The temp files created by the 'diff' and 'merge' commands are now named by prepending a new prefix to the file name, rather than appending a suffix. This should avoid confusing diff/merge programs that depend on the suffix to guess the type of the file contents. * We now set the keepalive option on the server socket, to make sure that the server times out if the communication link is unexpectedly broken. * Bug fixes: + When updating small files, Unison now closes the destination file. + File permissions are properly updated when the file is behind a followed link. + Several other small fixes.

Changes since 2.6.38: * Major Windows performance improvement! We've added a preference fastcheck that makes Unison look only at a file's creation time and last-modified time to check whether it has changed. This should result in a huge speedup when checking for updates in large replicas. When this switch is set, Unison will use file creation times as 'pseudo inode numbers' when scanning Windows replicas for updates, instead of reading the full contents of every file. This may cause Unison to miss propagating an update if the create time, modification time, and length of the file are all unchanged by the update (this is not easy to achieve, but it can be done). However, Unison will never overwrite such an update with a change from the other replica, since it always does a safe check for updates just before propagating a change. Thus, it is reasonable to use this switch most of the time and occasionally run Unison once with fastcheck set to false, if you are worried that Unison may have overlooked an update. Warning: This change is has not yet been thoroughly field-tested. If you set the fastcheck preference, pay careful attention to what Unison is doing. * New functionality: centralized backups and merging + This version incorporates two pieces of major new functionality, implemented by Sylvain Roy during a summer internship at Penn: a centralized backup facility that keeps a full backup of (selected files in) each replica, and a merging feature that allows Unison to invoke an external file-merging tool to resolve conflicting changes to individual files. + Centralized backups: o Unison now maintains full backups of the last-synchronized versions of (some of) the files in each replica; these function both as backups in the usual sense and as the "common version" when invoking external merge programs. o The backed up files are stored in a directory /.unison/backup on each host. (The name of this directory can be changed by setting the environment variable UNISONBACKUPDIR.) o The predicate backup controls which files are actually backed up: giving the preference 'backup = Path *' causes backing up of all files. o Files are added to the backup directory whenever unison updates its archive. This means that # When unison reconstructs its archive from scratch (e.g., because of an upgrade, or because the archive files have been manually deleted), all files will be backed up. # Otherwise, each file will be backed up the first time unison propagates an update for it. o The preference backupversions controls how many previous versions of each file are kept. The default is 2 (i.e., the last synchronized version plus one backup). o For backward compatibility, the backups preference is also still supported, but backup is now preferred. o It is OK to manually delete files from the backup directory (or to throw away the directory itself). Before unison uses any of these files for anything important, it checks that its fingerprint matches the one that it expects. + Merging: o Both user interfaces offer a new 'merge' command, invoked by pressing 'm' (with a changed file selected). o The actual merging is performed by an external program. The preferences merge and merge2 control how this program is invoked. If a backup exists for this file (see the backup preference), then the merge preference is used for this purpose; otherwise merge2 is used. In both cases, the value of the preference should be a string representing the command that should be passed to a shell to invoke the merge program. Within this string, the special substrings CURRENT1, CURRENT2, NEW, and OLD may appear at any point. Unison will substitute these as follows before invoking the command: # CURRENT1 is replaced by the name of the local copy of the file; # CURRENT2 is replaced by the name of a temporary file, into which the contents of the remote copy of the file have been transferred by Unison prior to performing the merge; # NEW is replaced by the name of a temporary file that Unison expects to be written by the merge program when it finishes, giving the desired new contents of the file; and # OLD is replaced by the name of the backed up copy of the original version of the file (i.e., its state at the end of the last successful run of Unison), if one exists (applies only to merge, not merge2). For example, on Unix systems setting the merge preference to merge = diff3 -m CURRENT1 OLD CURRENT2 > NEW

             will tell Unison to use the external diff3 program for
             merging.
             A large number of external merging programs are
             available. For example, emacs users may find the
             following convenient:
merge2 = emacs -q --eval '(ediff-merge-files "CURRENT1" "CURRENT2"
           nil "NEW")'
merge = emacs -q --eval '(ediff-merge-files-with-ancestor
           "CURRENT1" "CURRENT2" "OLD" nil "NEW")'

             (These commands are displayed here on two lines to avoid
             running off the edge of the page. In your preference
             file, each should be written on a single line.)
           o If the external program exits without leaving any file at
             the path NEW, Unison considers the merge to have failed.
             If the merge program writes a file called NEW but exits
             with a non-zero status code, then Unison considers the
             merge to have succeeded but to have generated conflicts.
             In this case, it attempts to invoke an external editor so
             that the user can resolve the conflicts. The value of the
             editor preference controls what editor is invoked by
             Unison. The default is emacs.
           o Please send us suggestions for other useful values of the
             merge2 and merge preferences - we'd like to give several
             examples in the manual.
 * Smaller changes:
      + When one preference file includes another, unison no longer
        adds the suffix '.prf' to the included file by default. If a
        file with precisely the given name exists in the .unison
        directory, it will be used; otherwise Unison will add .prf, as
        it did before. (This change means that included preference
        files can be named blah.include instead of blah.prf, so that
        unison will not offer them in its 'choose a preference file'
        dialog.)
      + For Linux systems, we now offer both a statically linked and a
        dynamically linked executable. The static one is larger, but
        will probably run on more systems, since it doesn't depend on
        the same versions of dynamically linked library modules being
        available.
      + Fixed the force and prefer preferences, which were getting the
        propagation direction exactly backwards.
      + Fixed a bug in the startup code that would cause unison to
        crash when the default profile (~/.unison/default.prf) does
        not exist.
      + Fixed a bug where, on the run when a profile is first created,
        Unison would confusingly display the roots in reverse order in
        the user interface.
 * For developers:
      + We've added a module dependency diagram to the source
        distribution, in src/DEPENDENCIES.ps, to help new prospective
        developers with navigating the code.

Changes since 2.6.11: * INCOMPATIBLE CHANGE: Archive format has changed. * INCOMPATIBLE CHANGE: The startup sequence has been completely rewritten and greatly simplified. The main user-visible change is that the defaultpath preference has been removed. Its effect can be approximated by using multiple profiles, with include directives to incorporate common settings. All uses of defaultpath in existing profiles should be changed to path. Another change in startup behavior that will affect some users is that it is no longer possible to specify roots both in the profile and on the command line. You can achieve a similar effect, though, by breaking your profile into two: default.prf = root = blah root = foo include common

common.prf =

   Now do

unison common root1 root2

   when you want to specify roots explicitly.
 * The -prefer and -force options have been extended to allow users to
   specify that files with more recent modtimes should be propagated,
   writing either -prefer newer or -force newer. (For symmetry, Unison
   will also accept -prefer older or -force older.) The -force
   older/newer options can only be used when -times is also set.
   The graphical user interface provides access to these facilities on
   a one-off basis via the Actions menu.
 * Names of roots can now be "aliased" to allow replicas to be
   relocated without changing the name of the archive file where
   Unison stores information between runs. (This feature is for
   experts only. See the "Archive Files" section of the manual for
   more information.)
 * Graphical user-interface:
      + A new command is provided in the Synchronization menu for
        switching to a new profile without restarting Unison from
        scratch.
      + The GUI also supports one-key shortcuts for commonly used
        profiles. If a profile contains a preference of the form 'key
        = n', where n is a single digit, then pressing this key will
        cause Unison to immediately switch to this profile and begin
        synchronization again from scratch. (Any actions that may have
        been selected for a set of changes currently being displayed
        will be discarded.)
      + Each profile may include a preference 'label = <string>'
        giving a descriptive string that described the options
        selected in this profile. The string is listed along with the
        profile name in the profile selection dialog, and displayed in
        the top-right corner of the main Unison window.
 * Minor:
      + Fixed a bug that would sometimes cause the 'diff' display to
        order the files backwards relative to the main user interface.
        (Thanks to Pascal Brisset for this fix.)
      + On Unix systems, the graphical version of Unison will check
        the DISPLAY variable and, if it is not set, automatically fall
        back to the textual user interface.
      + Synchronization paths (path preferences) are now matched
        against the ignore preferences. So if a path is both specified
        in a path preference and ignored, it will be skipped.
      + Numerous other bugfixes and small improvements.

Changes since 2.6.1: * The synchronization of modification times has been disabled for directories. * Preference files may now include lines of the form include , which will cause name.prf to be read at that point. * The synchronization of permission between Windows and Unix now works properly. * A binding CYGWIN=binmode in now added to the environment so that the Cygwin port of OpenSSH works properly in a non-Cygwin context. * The servercmd and addversionno preferences can now be used together: -addversionno appends an appropriate -NNN to the server command, which is found by using the value of the -servercmd preference if there is one, or else just unison. * Both '-pref=val' and '-pref val' are now allowed for boolean values. (The former can be used to set a preference to false.) * Lot of small bugs fixed.

Changes since 2.5.31: * The log preference is now set to true by default, since the log file seems useful for most users. * Several miscellaneous bugfixes (most involving symlinks).

Changes since 2.5.25: * INCOMPATIBLE CHANGE: Archive format has changed (again). * Several significant bugs introduced in 2.5.25 have been fixed.

Changes since 2.5.1: * INCOMPATIBLE CHANGE: Archive format has changed. Make sure you synchronize your replicas before upgrading, to avoid spurious conflicts. The first sync after upgrading will be slow. * New functionality: + Unison now synchronizes file modtimes, user-ids, and group-ids. These new features are controlled by a set of new preferences, all of which are currently false by default. o When the times preference is set to true, file modification times are propaged. (Because the representations of time may not have the same granularity on both replicas, Unison may not always be able to make the modtimes precisely equal, but it will get them as close as the operating systems involved allow.) o When the owner preference is set to true, file ownership information is synchronized. o When the group preference is set to true, group information is synchronized. o When the numericIds preference is set to true, owner and group information is synchronized numerically. By default, owner and group numbers are converted to names on each replica and these names are synchronized. (The special user id 0 and the special group 0 are never mapped via user/group names even if this preference is not set.) + Added an integer-valued preference perms that can be used to control the propagation of permission bits. The value of this preference is a mask indicating which permission bits should be synchronized. It is set by default to 0o1777: all bits but the set-uid and set-gid bits are synchronised (synchronizing these latter bits can be a security hazard). If you want to synchronize all bits, you can set the value of this preference to -1. + Added a log preference (default false), which makes Unison keep a complete record of the changes it makes to the replicas. By default, this record is written to a file called unison.log in the user's home directory (the value of the HOME environment variable). If you want it someplace else, set the logfile preference to the full pathname you want Unison to use. + Added an ignorenot preference that maintains a set of patterns for paths that should definitely not be ignored, whether or not they match an ignore pattern. (That is, a path will now be ignored iff it matches an ignore pattern and does not match any ignorenot patterns.) * User-interface improvements: + Roots are now displayed in the user interface in the same order as they were given on the command line or in the preferences file. + When the batch preference is set, the graphical user interface no longer waits for user confirmation when it displays a warning message: it simply pops up an advisory window with a Dismiss button at the bottom and keeps on going. + Added a new preference for controlling how many status messages are printed during update detection: statusdepth controls the maximum depth for paths on the local machine (longer paths are not displayed, nor are non-directory paths). The value should be an integer; default is 1. + Removed the trace and silent preferences. They did not seem very useful, and there were too many preferences for controlling output in various ways. + The text UI now displays just the default command (the one that will be used if the user just types ) instead of all available commands. Typing ? will print the full list of possibilities. + The function that finds the canonical hostname of the local host (which is used, for example, in calculating the name of the archive file used to remember which files have been synchronized) normally uses the gethostname operating system call. However, if the environment variable UNISONLOCALHOSTNAME is set, its value will now be used instead. This makes it easier to use Unison in situations where a machine's name changes frequently (e.g., because it is a laptop and gets moved around a lot). + File owner and group are now displayed in the "detail window" at the bottom of the screen, when unison is configured to synchronize them. * For hackers: + Updated to Jacques Garrigue's new version of lablgtk, which means we can throw away our local patched version. If you're compiling the GTK version of unison from sources, you'll need to update your copy of lablgtk to the developers release. (Warning: installing lablgtk under Windows is currently a bit challenging.) + The TODO.txt file (in the source distribution) has been cleaned up and reorganized. The list of pending tasks should be much easier to make sense of, for people that may want to contribute their programming energies. There is also a separate file BUGS.txt for open bugs. + The Tk user interface has been removed (it was not being maintained and no longer compiles). + The debug preference now prints quite a bit of additional information that should be useful for identifying sources of problems. + The version number of the remote server is now checked right away during the connection setup handshake, rather than later. (Somebody sent a bug report of a server crash that turned out to come from using inconsistent versions: better to check this earlier and in a way that can't crash either client or server.) + Unison now runs correctly on 64-bit architectures (e.g. Alpha linux). We will not be distributing binaries for these architectures ourselves (at least for a while) but if someone would like to make them available, we'll be glad to provide a link to them. * Bug fixes: + Pattern matching (e.g. for ignore) is now case-insensitive when Unison is in case-insensitive mode (i.e., when one of the replicas is on a windows machine). + Some people had trouble with mysterious failures during propagation of updates, where files would be falsely reported as having changed during synchronization. This should be fixed. + Numerous smaller fixes.

Changes since 2.4.1: * Added a number of 'sorting modes' for the user interface. By default, conflicting changes are displayed at the top, and the rest of the entries are sorted in alphabetical order. This behavior can be changed in the following ways: + Setting the sortnewfirst preference to true causes newly created files to be displayed before changed files. + Setting sortbysize causes files to be displayed in increasing order of size. + Giving the preference sortfirst= (where is a path descriptor in the same format as 'ignore' and 'follow' patterns, causes paths matching this pattern to be displayed first. + Similarly, giving the preference sortlast= causes paths matching this pattern to be displayed last. The sorting preferences are described in more detail in the user manual. The sortnewfirst and sortbysize flags can also be accessed from the 'Sort' menu in the graphical user interface. * Added two new preferences that can be used to change unison's fundamental behavior to make it more like a mirroring tool instead of a synchronizer. + Giving the preference prefer with argument (by adding -prefer to the command line or prefer=) to your profile) means that, if there is a conflict, the contents of should be propagated to the other replica (with no questions asked). Non-conflicting changes are treated as usual. + Giving the preference force with argument will make unison resolve all differences in favor of the given root, even if it was the other replica that was changed. These options should be used with care! (More information is available in the manual.) * Small changes: + Changed default answer to 'Yes' in all two-button dialogs in the graphical interface (this seems more intuitive). + The rsync preference has been removed (it was used to activate rsync compression for file transfers, but rsync compression is now enabled by default). + In the text user interface, the arrows indicating which direction changes are being propagated are printed differently when the user has overridden Unison's default recommendation (====> instead of ---->). This matches the behavior of the graphical interface, which displays such arrows in a different color. + Carriage returns (Control-M's) are ignored at the ends of lines in profiles, for Windows compatibility. + All preferences are now fully documented in the user manual.

Changes since 2.3.12: * INCOMPATIBLE CHANGE: Archive format has changed. Make sure you synchronize your replicas before upgrading, to avoid spurious conflicts. The first sync after upgrading will be slow. * New/improved functionality: + A new preference -sortbysize controls the order in which changes are displayed to the user: when it is set to true, the smallest changed files are displayed first. (The default setting is false.) + A new preference -sortnewfirst causes newly created files to be listed before other updates in the user interface. + We now allow the ssh protocol to specify a port. + Incompatible change: The unison: protocol is deprecated, and we added file: and socket:. You may have to modify your profiles in the .unison directory. If a replica is specified without an explicit protocol, we now assume it refers to a file. (Previously "//saul/foo" meant to use SSH to connect to saul, then access the foo directory. Now it means to access saul via a remote file mechanism such as samba; the old effect is now achieved by writing ssh://saul/foo.) + Changed the startup sequence for the case where roots are given but no profile is given on the command line. The new behavior is to use the default profile (creating it if it does not exist), and temporarily override its roots. The manual claimed that this case would work by reading no profile at all, but AFAIK this was never true. + In all user interfaces, files with conflicts are always listed first + A new preference 'sshversion' can be used to control which version of ssh should be used to connect to the server. Legal values are 1 and 2. (Default is empty, which will make unison use whatever version of ssh is installed as the default 'ssh' command.) + The situation when the permissions of a file was updated the same on both side is now handled correctly (we used to report a spurious conflict) * Improvements for the Windows version: + The fact that filenames are treated case-insensitively under Windows should now be handled correctly. The exact behavior is described in the cross-platform section of the manual. + It should be possible to synchronize with Windows shares, e.g., //host/drive/path. + Workarounds to the bug in syncing root directories in Windows. The most difficult thing to fix is an ocaml bug: Unix.opendir fails on c: in some versions of Windows. * Improvements to the GTK user interface (the Tk interface is no longer being maintained): + The UI now displays actions differently (in blue) when they have been explicitly changed by the user from Unison's default recommendation. + More colorful appearance. + The initial profile selection window works better. + If any transfers failed, a message to this effect is displayed along with 'Synchronization complete' at the end of the transfer phase (in case they may have scrolled off the top). + Added a global progress meter, displaying the percentage of total bytes that have been transferred so far. * Improvements to the text user interface: + The file details will be displayed automatically when a conflict is been detected. + when a warning is generated (e.g. for a temporary file left over from a previous run of unison) Unison will no longer wait for a response if it is running in -batch mode. + The UI now displays a short list of possible inputs each time it waits for user interaction. + The UI now quits immediately (rather than looping back and starting the interaction again) if the user presses 'q' when asked whether to propagate changes. + Pressing 'g' in the text user interface will proceed immediately with propagating updates, without asking any more questions. * Documentation and installation changes: + The manual now includes a FAQ, plus sections on common problems and on tricks contributed by users. + Both the download page and the download directory explicitly say what are the current stable and beta-test version numbers. + The OCaml sources for the up-to-the-minute developers' version (not guaranteed to be stable, or even to compile, at any given time!) are now available from the download page. + Added a subsection to the manual describing cross-platform issues (case conflicts, illegal filenames) * Many small bug fixes and random improvements.

Changes since 2.3.1: * Several bug fixes. The most important is a bug in the rsync module that would occasionally cause change propagation to fail with a 'rename' error.

Changes since 2.2: * The multi-threaded transport system is now disabled by default. (It is not stable enough yet.) * Various bug fixes. * A new experimental feature: The final component of a -path argument may now be the wildcard specifier *. When Unison sees such a path, it expands this path on the client into into the corresponding list of paths by listing the contents of that directory. Note that if you use wildcard paths from the command line, you will probably need to use quotes or a backslash to prevent the * from being interpreted by your shell. If both roots are local, the contents of the first one will be used for expanding wildcard paths. (Nb: this is the first one after the canonization step - i.e., the one that is listed first in the user interface - not the one listed first on the command line or in the preferences file.)

Changes since 2.1: * The transport subsystem now includes an implementation by Sylvain Gommier and Norman Ramsey of Tridgell and Mackerras's rsync protocol. This protocol achieves much faster transfers when only a small part of a large file has been changed by sending just diffs. This feature is mainly helpful for transfers over slow links--on fast local area networks it can actually degrade performance--so we have left it off by default. Start unison with the -rsync option (or put rsync=true in your preferences file) to turn it on. * "Progress bars" are now displayed during remote file transfers, showing what percentage of each file has been transferred so far. * The version numbering scheme has changed. New releases will now be have numbers like 2.2.30, where the second component is incremented on every significant public release and the third component is the "patch level." * Miscellaneous improvements to the GTK-based user interface. * The manual is now available in PDF format. * We are experimenting with using a multi-threaded transport subsystem to transfer several files at the same time, making much more effective use of available network bandwidth. This feature is not completely stable yet, so by default it is disabled in the release version of Unison. If you want to play with the multi-threaded version, you'll need to recompile Unison from sources (as described in the documentation), setting the THREADS flag in Makefile.OCaml to true. Make sure that your OCaml compiler has been installed with the -with-pthreads configuration option. (You can verify this by checking whether the file threads/threads.cma in the OCaml standard library directory contains the string -lpthread near the end.)

Changes since 1.292: * Reduced memory footprint (this is especially important during the first run of unison, where it has to gather information about all the files in both repositories). * Fixed a bug that would cause the socket server under NT to fail after the client exits. * Added a SHIFT modifier to the Ignore menu shortcut keys in GTK interface (to avoid hitting them accidentally).

Changes since 1.231: * Tunneling over ssh is now supported in the Windows version. See the installation section of the manual for detailed instructions. * The transport subsystem now includes an implementation of the rsync protocol, built by Sylvain Gommier and Norman Ramsey. This protocol achieves much faster transfers when only a small part of a large file has been changed by sending just diffs. The rsync feature is off by default in the current version. Use the -rsync switch to turn it on. (Nb. We still have a lot of tuning to do: you may not notice much speedup yet.) * We're experimenting with a multi-threaded transport subsystem, written by Jerome Vouillon. The downloadable binaries are still single-threaded: if you want to try the multi-threaded version, you'll need to recompile from sources. (Say make THREADS=true.) Native thread support from the compiler is required. Use the option -threads N to select the maximal number of concurrent threads (default is 5). Multi-threaded and single-threaded clients/servers can interoperate. * A new GTK-based user interface is now available, thanks to Jacques Garrigue. The Tk user interface still works, but we'll be shifting development effort to the GTK interface from now on. * OCaml 3.00 is now required for compiling Unison from sources. The modules uitk and myfileselect have been changed to use labltk instead of camltk. To compile the Tk interface in Windows, you must have ocaml-3.00 and tk8.3. When installing tk8.3, put it in c:\Tcl rather than the suggested c:\Program Files\Tcl, and be sure to install the headers and libraries (which are not installed by default). * Added a new -addversionno switch, which causes unison to use unison- instead of just unison as the remote server command. This allows multiple versions of unison to coexist conveniently on the same server: whichever version is run on the client, the same version will be selected on the server.

Changes since 1.219: * INCOMPATIBLE CHANGE: Archive format has changed. Make sure you synchronize your replicas before upgrading, to avoid spurious conflicts. The first sync after upgrading will be slow. * This version fixes several annoying bugs, including: + Some cases where propagation of file permissions was not working. + umask is now ignored when creating directories + directories are create writable, so that a read-only directory and its contents can be propagated. + Handling of warnings generated by the server. + Synchronizing a path whose parent is not a directory on both sides is now flagged as erroneous. + Fixed some bugs related to symnbolic links and nonexistent roots. o When a change (deletion or new contents) is propagated onto a 'follow'ed symlink, the file pointed to by the link is now changed. (We used to change the link itself, which doesn't fit our assertion that 'follow' means the link is completely invisible) o When one root did not exist, propagating the other root on top of it used to fail, because unison could not calculate the working directory into which to write changes. This should be fixed. * A human-readable timestamp has been added to Unison's archive files. * The semantics of Path and Name regular expressions now correspond better. * Some minor improvements to the text UI (e.g. a command for going back to previous items) * The organization of the export directory has changed -- should be easier to find / download things now.

Changes since 1.200: * INCOMPATIBLE CHANGE: Archive format has changed. Make sure you synchronize your replicas before upgrading, to avoid spurious conflicts. The first sync after upgrading will be slow. * This version has not been tested extensively on Windows. * Major internal changes designed to make unison safer to run at the same time as the replicas are being changed by the user. * Internal performance improvements.

Changes since 1.190: * INCOMPATIBLE CHANGE: Archive format has changed. Make sure you synchronize your replicas before upgrading, to avoid spurious conflicts. The first sync after upgrading will be slow. * A number of internal functions have been changed to reduce the amount of memory allocation, especially during the first synchronization. This should help power users with very big replicas. * Reimplementation of low-level remote procedure call stuff, in preparation for adding rsync-like smart file transfer in a later release. * Miscellaneous bug fixes.

Changes since 1.180: * INCOMPATIBLE CHANGE: Archive format has changed. Make sure you synchronize your replicas before upgrading, to avoid spurious conflicts. The first sync after upgrading will be slow. * Fixed some small bugs in the interpretation of ignore patterns. * Fixed some problems that were preventing the Windows version from working correctly when click-started. * Fixes to treatment of file permissions under Windows, which were causing spurious reports of different permissions when synchronizing between windows and unix systems. * Fixed one more non-tail-recursive list processing function, which was causing stack overflows when synchronizing very large replicas.

Changes since 1.169: * The text user interface now provides commands for ignoring files. * We found and fixed some more non-tail-recursive list processing functions. Some power users have reported success with very large replicas. * INCOMPATIBLE CHANGE: Files ending in .tmp are no longer ignored automatically. If you want to ignore such files, put an appropriate ignore pattern in your profile. * INCOMPATIBLE CHANGE: The syntax of ignore and follow patterns has changed. Instead of putting a line of the form ignore =

   in your profile (.unison/default.prf), you should put:
             ignore = Regex <regexp>

   Moreover, two other styles of pattern are also recognized:
             ignore = Name <name>

   matches any path in which one component matches <name>, while
             ignore = Path <path>

   matches exactly the path <path>.
   Standard "globbing" conventions can be used in <name> and <path>:
      + a ? matches any single character except /
      + a * matches any sequence of characters not including /
      + [xyz] matches any character from the set {x, y, z }
      + {a,bb,ccc} matches any one of a, bb, or ccc.
   See the user manual for some examples.

Changes since 1.146: * Some users were reporting stack overflows when synchronizing huge directories. We found and fixed some non-tail-recursive list processing functions, which we hope will solve the problem. Please give it a try and let us know. * Major additions to the documentation.

Changes since 1.142: * Major internal tidying and many small bugfixes. * Major additions to the user manual. * Unison can now be started with no arguments - it will prompt automatically for the name of a profile file containing the roots to be synchronized. This makes it possible to start the graphical UI from a desktop icon. * Fixed a small bug where the text UI on NT was raising a 'no such signal' exception.

Changes since 1.139: * The precompiled windows binary in the last release was compiled with an old OCaml compiler, causing propagation of permissions not to work (and perhaps leading to some other strange behaviors we've heard reports about). This has been corrected. If you're using precompiled binaries on Windows, please upgrade. * Added a -debug command line flag, which controls debugging of various modules. Say -debug XXX to enable debug tracing for module XXX, or -debug all to turn on absolutely everything. * Fixed a small bug where the text UI on NT was raising a 'no such signal' exception.

Changes since 1.111: * INCOMPATIBLE CHANGE: The names and formats of the preference files in the .unison directory have changed. In particular: + the file "prefs" should be renamed to default.prf + the contents of the file "ignore" should be merged into default.prf. Each line of the form REGEXP in ignore should become a line of the form ignore = REGEXP in default.prf. * Unison now handles permission bits and symbolic links. See the manual for details. * You can now have different preference files in your .unison directory. If you start unison like this unison profilename

   (i.e. with just one "anonymous" command-line argument), then the
   file ~/.unison/profilename.prf will be loaded instead of
   default.prf.
 * Some improvements to terminal handling in the text user interface
 * Added a switch -killServer that terminates the remote server
   process when the unison client is shutting down, even when using
   sockets for communication. (By default, a remote server created
   using ssh/rsh is terminated automatically, while a socket server is
   left running.)
 * When started in 'socket server' mode, unison prints 'server
   started' on stderr when it is ready to accept connections. (This
   may be useful for scripts that want to tell when a socket-mode
   server has finished initialization.)
 * We now make a nightly mirror of our current internal development
   tree, in case anyone wants an up-to-the-minute version to hack
   around with.
 * Added a file CONTRIB with some suggestions for how to help us make
   Unison better.