path: root/doc/git-annex.mdwn

# NAME

git-annex - manage files with git, without checking their contents in

# SYNOPSIS

git annex command [params ...]

# DESCRIPTION

git-annex allows managing files with git, without checking the file
contents into git. While that may seem paradoxical, it is useful when
dealing with files larger than git can currently easily handle, whether due
to limitations in memory, checksumming time, or disk space.

Even without file content tracking, being able to manage files with git,
move files around and delete files with versioned directory trees, and use
branches and distributed clones, are all very handy reasons to use git. And
annexed files can co-exist in the same git repository with regularly
versioned files, which is convenient for maintaining documents, Makefiles,
etc that are associated with annexed files but that benefit from full
revision control.

When a file is annexed, its content is moved into a key-value store, and
a symlink is made that points to the content. These symlinks are checked into
git and versioned like regular files. You can move them around, delete
them, and so on. Pushing to another git repository will make git-annex
there aware of the annexed file, and it can be used to retrieve its
content from the key-value store.

# EXAMPLES

	# git annex get video/hackity_hack_and_kaxxt.mov
	get video/hackity_hack_and_kaxxt.mov (not available)
	  I was unable to access these remotes: server
	  Try making some of these repositories available:
	  	5863d8c0-d9a9-11df-adb2-af51e6559a49  -- my home file server
	   	58d84e8a-d9ae-11df-a1aa-ab9aa8c00826  -- portable USB drive
	   	ca20064c-dbb5-11df-b2fe-002170d25c55  -- backup SATA drive
	failed
	# sudo mount /media/usb
	# git remote add usbdrive /media/usb
	# git annex get video/hackity_hack_and_kaxxt.mov
	get video/hackity_hack_and_kaxxt.mov (from usbdrive...) ok
	
	# git annex add iso
	add iso/Debian_5.0.iso ok
	
	# git annex drop iso/Debian_4.0.iso
	drop iso/Debian_4.0.iso ok
	
	# git annex move iso --to=usbdrive
	move iso/Debian_5.0.iso (moving to usbdrive...) ok

# COMMONLY USED COMMANDS

Like many git commands, git-annex can be passed a path that
is either a file or a directory. In the latter case it acts on all relevant
files in the directory. When no path is specified, most git-annex commands
default to acting on all relevant files in the current directory (and
subdirectories).

* `help`

  Display built-in help.

  For help on a specific command, use `git annex help command`

* `add [path ...]`

  Adds files in the path to the annex. If no path is specified, adds
  files from the current directory and below. 
  
  See [[git-annex-add]](1) for details.

* `get [path ...]`

  Makes the content of annexed files available in this repository.
  
  See [[git-annex-get]](1) for details.

* `drop [path ...]`

  Drops the content of annexed files from this repository.
  
  See [[git-annex-drop]](1) for details.

* `move [path ...] [--from=remote|--to=remote]`

  Moves the content of files from or to another remote.

  See [[git-annex-move]](1) for details.

* `copy [path ...] [--from=remote|--to=remote]`

  Copies the content of files from or to another remote.

  See [[git-annex-copy]](1) for details.

* `status [path ...]`

  Similar to `git status --short`, displays the status of the files in the
  working tree. Particularly useful in direct mode.

  See [[git-annex-status]](1) for details.

* `unlock [path ...]`

  Unlock annexed files for modification.
  
  See [[git-annex-unlock]](1) for details.

* `edit [path ...]`

  This is an alias for the unlock command. May be easier to remember,
  if you think of this as allowing you to edit an annexed file.

* `lock [path ...]`

  Use this to undo an unlock command if you don't want to modify
  the files, or have made modifications you want to discard.
  
  See [[git-annex-lock]](1) for details.

* `sync [remote ...]`

  Synchronize local repository with remotes.
  
  See [[git-annex-sync]](1) for details.

* `mirror [path ...] [--to=remote|--from=remote]`

  Mirror content of files to/from another repository.
  
  See [[git-annex-mirror]](1) for details.

* `addurl [url ...]`

  Downloads each url to its own file, which is added to the annex.
  
  See [[git-annex-addurl]](1) for details.

* `rmurl file url`

  Record that the file is no longer available at the url.
  
  See [[git-annex-rmurl]](1) for details.

* `import [path ...]`

  Move and add files from outside git working copy into the annex.
  
  See [[git-annex-import]](1) for details.

* `importfeed [url ...]`

  Imports the contents of podcast feeds into the annex.
  
  See [[git-annex-importfeed]](1) for details.

* `export treeish --to remote`

  Export content to a remote.

  See [[git-annex-export]](1) for details.

* `undo [filename|directory] ...`

  Undo last change to a file or directory.
  
  See [[git-annex-undo]](1) for details.

* `multicast`

  Multicast file distribution.

  See [[git-annex-multicast]](1) for details.

* `watch`

  Watch for changes and autocommit.
  
  See [[git-annex-watch]](1) for details.

* `assistant`

  Automatically sync folders between devices.

  See [[git-annex-assistant]](1) for details.

* `webapp`

  Opens a web app, that allows easy setup of a git-annex repository,
  and control of the git-annex assistant. If the assistant is not
  already running, it will be started.

  See [[git-annex-webapp]](1) for details.

# REPOSITORY SETUP COMMANDS

* `init [description]`

  Until a repository (or one of its remotes) has been initialized,
  git-annex will refuse to operate on it, to avoid accidentally
  using it in a repository that was not intended to have an annex.
  
  See [[git-annex-init]](1) for details.

* `describe repository description`

  Changes the description of a repository.
  
  See [[git-annex-describe]](1) for details.

* `initremote name type=value [param=value ...]`

  Creates a new special remote, and adds it to `.git/config`.

  See [[git-annex-initremote]](1) for details.
  
* `enableremote name [param=value ...]`

  Enables use of an existing special remote in the current repository.
  
  See [[git-annex-enableremote]](1) for details.

* `enable-tor`

  Sets up tor hidden service.
  
  See [[git-annex-enable-tor]](1) for details.

* `numcopies [N]`

  Configure desired number of copies.
  
  See [[git-annex-numcopies]](1) for details.

* `trust [repository ...]`

  Records that a repository is trusted to not unexpectedly lose
  content. Use with care.
  
  See [[git-annex-trust]](1) for details.

* `untrust [repository ...]`

  Records that a repository is not trusted and could lose content
  at any time.
  
  See [[git-annex-untrust]](1) for details.

* `semitrust [repository ...]`

  Returns a repository to the default semi trusted state.
  
  See [[git-annex-semitrust]](1) for details.

* `group repository groupname`

  Add a repository to a group.
  
  See [[git-annex-group]](1) for details.

* `ungroup repository groupname`

  Removes a repository from a group.
  
  See [[git-annex-ungroup]](1) for details.

* `wanted repository [expression]`
  
  Get or set preferred content expression.

  See [[git-annex-wanted]](1) for details.

* `groupwanted groupname [expression]`

  Get or set groupwanted expression.

  See [[git-annex-groupwanted]](1) for details.

* `required repository [expression]`
  
  Get or set required content expression.
  
  See [[git-annex-required]](1) for details.

* `schedule repository [expression]`

  Get or set scheduled jobs.

  See [[git-annex-schedule]](1) for details.

* `config`

  Get and set other configuration stored in git-annex branch.
  
  See [[git-annex-config]](1) for details.

* `vicfg`

  Opens EDITOR on a temp file containing most of the above configuration
  settings, as well as a few others, and when it exits, stores any changes
  made back to the git-annex branch.
  
  See [[git-annex-vicfg]](1) for details.

* `direct`

  Switches a repository to use direct mode, where rather than symlinks to
  files, the files are directly present in the repository.
  
  See [[git-annex-direct]](1) for details.

* `indirect`

  Switches a repository back from direct mode to the default, indirect mode.
  
  See [[git-annex-indirect]](1) for details.

* `adjust`

  Switches a repository to use an adjusted branch, which can automatically
  unlock all files, etc.
  
  See [[git-annex-adjust]](1) for details.

# REPOSITORY MAINTENANCE COMMANDS

* `fsck [path ...]`

  Checks the annex consistency, and warns about or fixes any problems found. 
  This is a good complement to `git fsck`.

  See [[git-annex-fsck]](1) for details.

* `expire [repository:]time ...`

  Expires repositories that have not recently performed an activity
  (such as a fsck).

  See [[git-annex-expire]](1) for details.

* `unused`

  Checks the annex for data that does not correspond to any files present
  in any tag or branch, and prints a numbered list of the data.
  
  See [[git-annex-unused]](1) for details.

* `dropunused [number|range ...]`

  Drops the data corresponding to the numbers, as listed by the last
  `git annex unused`
  
  See [[git-annex-dropunused]](1) for details.

* `addunused [number|range ...]`

  Adds back files for the content corresponding to the numbers or ranges,
  as listed by the last `git annex unused`.
  
  See [[git-annex-addunused]](1) for details.

* `fix [path ...]`

  Fixes up symlinks that have become broken to again point to annexed content.

  See [[git-annex-fix]](1) for details.

* `merge`

  Automatically merge changes from remotes.

  See [[git-annex-merge]](1) for details.

* `upgrade`

  Upgrades the repository to current layout.
  
  See [[git-annex-upgrade]](1) for details.

* `dead [repository ...] [--key key]`

  Indicates that a repository or a single key has been irretrievably lost.
  
  See [[git-annex-dead]](1) for details.

* `forget`

  Causes the git-annex branch to be rewritten, throwing away historical
  data about past locations of files.
  
  See [[git-annex-forget]](1) for details.

* `repair`

  This can repair many of the problems with git repositories that `git fsck`
  detects, but does not itself fix. It's useful if a repository has become
  badly damaged. One way this can happen is if a repository used by git-annex
  is on a removable drive that gets unplugged at the wrong time.
  
  See [[git-annex-repair]](1) for details.

* `p2p`

  Configure peer-2-Peer links between repositories.

  See [[git-annex-p2p]](1) for details.

# QUERY COMMANDS

* `find [path ...]`

  Outputs a list of annexed files in the specified path. With no path,
  finds files in the current directory and its subdirectories.

  See [[git-annex-find]](1) for details.

* `whereis [path ...]`

  Displays information about where the contents of files are located.
  
  See [[git-annex-whereis]](1) for details.

* `list [path ...]`

  Displays a table of remotes that contain the contents of the specified
  files. This is similar to whereis but a more compact display.
  
  See [[git-annex-list]](1) for details.

* `log [path ...]`

  Displays the location log for the specified file or files,
  showing each repository they were added to ("+") and removed from ("-").

  See [[git-annex-log]](1) for details.

* `info [directory|file|remote|uuid ...]`

  Displays statistics and other information for the specified item,
  which can be a directory, or a file, or a remote, or the uuid of a
  repository. 

  When no item is specified, displays statistics and information
  for the repository as a whole.
  
  See [[git-annex-info]](1) for details.

* `version`

  Shows the version of git-annex, as well as repository version information.
  
  See [[git-annex-version]](1) for details.

* `map`

  Generate map of repositories.

  See [[git-annex-map]](1) for details.

* `inprogress`

  Access files while they're being downloaded.

  See [[git-annex-inprogress]](1) for details.

# METADATA COMMANDS

* `metadata [path ...]`

  The content of an annexed file can have any number of metadata fields
  attached to it to describe it. Each metadata field can in turn
  have any number of values.

  This command can be used to set metadata, or show the currently set
  metadata.

  See [[git-annex-metadata]](1) for details.

* `view [tag ...] [field=value ...] [field=glob ...] [!tag ...] [field!=value ...]`

  Uses metadata to build a view branch of the files in the current branch,
  and checks out the view branch. Only files in the current branch whose
  metadata matches all the specified field values and tags will be
  shown in the view.

  See [[git-annex-view]](1) for details.

* `vpop [N]`

  Switches from the currently active view back to the previous view.
  Or, from the first view back to original branch.
 
  See [[git-annex-vpop]](1) for details.

* `vfilter [tag ...] [field=value ...] [!tag ...] [field!=value ...]`

  Filters the current view to only the files that have the
  specified field values and tags.
  
  See [[git-annex-vfilter]](1) for details.

* `vadd [field=glob ...] [field=value ...] [tag ...]`

  Changes the current view, adding an additional level of directories
  to categorize the files.
  
  See [[git-annex-vfilter]](1) for details.

* `vcycle`

  When a view involves nested subdirectories, this cycles the order.
  
  See [[git-annex-vcycle]](1) for details.

# UTILITY COMMANDS

* `migrate [path ...]`

  Changes the specified annexed files to use a different key-value backend.
  
  See [[git-annex-migrate]](1) for details.

* `reinject src dest`

  Moves the src file into the annex as the content of the dest file.
  This can be useful if you have obtained the content of a file from
  elsewhere and want to put it in the local annex.

  See [[git-annex-reinject]](1) for details.

* `unannex [path ...]`

  Use this to undo an accidental `git annex add` command. It puts the
  file back how it was before the add.
  
  See [[git-annex-unannex]](1) for details.

* `uninit`

  De-initialize git-annex and clean out repository.
  
  See [[git-annex-uninit]](1) for details.

* `reinit uuid|description`

  Initialize repository, reusing old UUID.
  
  See [[git-annex-reinit]](1) for details.

# PLUMBING COMMANDS

* `pre-commit [path ...]`

  This is meant to be called from git's pre-commit hook. `git annex init`
  automatically creates a pre-commit hook using this.
  
  See [[git-annex-pre-commit]](1) for details.

* `post-receive`

  This is meant to be called from git's post-receive hook. `git annex init`
  automatically creates a post-receive hook using this.
  
  See [[git-annex-post-receive]](1) for details.

* `lookupkey [file ...]`

  Looks up key used for file.

  See [[git-annex-lookupkey]](1) for details.

* `calckey [file ...]`

  Calculates the key that would be used to refer to a file.
  
  See [[git-annex-calckey]](1) for details.

* `contentlocation [key ..]`

  Looks up location of annexed content for a key.

  See [[git-annex-contentlocation]](1) for details.

* `examinekey [key ...]`

  Print information that can be determined purely by looking at the key.
  
  See [[git-annex-examinekey]](1) for details.

* `matchexpression`

  Checks if a preferred content expression matches provided data.
  
  See [[git-annex-matchexpression]](1) for details.

* `fromkey [key file]`

  Manually set up a file in the git repository to link to a specified key.
  
  See [[git-annex-fromkey]](1) for details.

* `registerurl [key url]`

  Registers an url for a key.
  
  See [[git-annex-registerurl]](1) for details.

* `setkey key file`

  Moves a file into the annex as the content of a key.
  
  See [[git-annex-setkey]](1) for details.

* `dropkey [key ...]`

  Drops annexed content for specified keys.
  
  See [[git-annex-dropkey]](1) for details.

* `transferkey key [--from=remote|--to=remote]`

  Transfers a key from or to a remote.
  
  See [[git-annex-transferkey]](1) for details.

* `transferkeys`
  
  Used internally by the assistant.

  See [[git-annex-transferkey]](1) for details.

* `setpresentkey key uuid [1|0]`

  This plumbing-level command changes git-annex's records about whether
  the specified key's content is present in a remote with the specified uuid.

  See [[git-annex-setpresentkey]](1) for details.

* `readpresentkey key uuid`

  Read records of where key is present.

  See [[git-annex-readpresentkey]](1) for details.

* `checkpresentkey key remote`

  Check if key is present in remote.
  
  See [[git-annex-checkpresentkey]](1) for details.

* `rekey [file key ...]`

  Change keys used for files.
  
  See [[git-annex-rekey]](1) for details.

* `findref [ref]`

  Lists files in a git ref.
  
  See [[git-annex-findref]](1) for details.

* `proxy -- git cmd [options]`

  Only useful in a direct mode repository, this runs the specified git
  command with a temporary work tree, and updates the working tree to
  reflect any changes staged or committed by the git command.
  
  See [[git-annex-proxy]](1) for details.

* `resolvemerge`

  Resolves a conflicted merge, by adding both conflicting versions of the
  file to the tree, using variants of their filename. This is done
  automatically when using `git annex sync` or `git annex merge`.

  See [[git-annex-resolvemerge]](1) for details.

* `diffdriver`

  This can be used to make `git diff` use an external diff driver with
  annexed files.

  See [[git-annex-diffdriver]](1) for details.

* `smudge`

  This command lets git-annex be used as a git filter driver, allowing
  annexed files in the git repository to be unlocked at all times, instead
  of being symlinks.

  See [[git-annex-smudge]](1) for details.

* `remotedaemon`

  Detects when network remotes have received git pushes and fetches from them.

  See [[git-annex-remotedaemon]](1) for details.

# TESTING COMMANDS

* `test`

  This runs git-annex's built-in test suite.
  
  See [[git-annex-test]](1) for details.

* `testremote remote`

  This tests a remote by generating some random objects and sending them to
  the remote, then redownloading them, removing them from the remote, etc.

  It's safe to run in an existing repository (the repository contents are
  not altered), although it may perform expensive data transfers.
  
  See [[git-annex-testremote]](1) for details.

* `fuzztest`

  Generates random changes to files in the current repository,
  for use in testing the assistant.
  
  See [[git-annex-fuzztest]](1) for details.

* `benchmark`

  This runs git-annex's built-in benchmarks, if it was built with
  benchmarking support.

# COMMON OPTIONS

These common options are accepted by all git-annex commands, and
may not be explicitly listed on their individual man pages.
(Many commands also accept the [[git-annex-matching-options]](1).)

* `--force`

  Force unsafe actions, such as dropping a file's content when no other
  source of it can be verified to still exist, or adding ignored files.
  Use with care.

* `--fast`

  Enable less expensive, but also less thorough versions of some commands.
  What is avoided depends on the command.

* `--quiet`

  Avoid the default verbose display of what is done; only show errors.

* `--verbose`

  Enable verbose display.

* `--debug`

  Show debug messages.

* `--no-debug`

  Disable debug messages.

* `--numcopies=n`

  Overrides the numcopies setting, forcing git-annex to ensure the
  specified number of copies exist.

  Note that setting numcopies to 0 is very unsafe.

* `--time-limit=time`

  Limits how long a git-annex command runs. The time can be something
  like "5h", or "30m" or even "45s" or "10d".

  Note that git-annex may continue running a little past the specified
  time limit, in order to finish processing a file.

  Also, note that if the time limit prevents git-annex from doing all it
  was asked to, it will exit with a special code, 101.

* `--trust=repository`
* `--semitrust=repository`
* `--untrust=repository`

  Overrides trust settings for a repository. May be specified more than once.

  The repository should be specified using the name of a configured remote,
  or the UUID or description of a repository.

* `--trust-glacier-inventory`

  Amazon Glacier inventories take hours to retrieve, and may not represent
  the current state of a repository. So git-annex does not trust that
  files that the inventory claims are in Glacier are really there.
  This switch can be used to allow it to trust the inventory.

  Be careful using this, especially if you or someone else might have recently
  removed a file from Glacier. If you try to drop the only other copy of the
  file, and this switch is enabled, you could lose data!

* `--backend=name`

  Specifies which key-value backend to use. This can be used when
  adding a file to the annex, or migrating a file. Once files
  are in the annex, their backend is known and this option is not
  necessary.

* `--user-agent=value`

  Overrides the User-Agent to use when downloading files from the web.

* `--notify-finish`

  Caused a desktop notification to be displayed after each successful
  file download and upload.

  (Only supported on some platforms, e.g. Linux with dbus. A no-op when
  not supported.)

* `--notify-start`

  Caused a desktop notification to be displayed when a file upload
  or download has started, or when a file is dropped.

* `-c name=value`

  Overrides git configuration settings. May be specified multiple times.

# CONFIGURATION VIA .git/config

Like other git commands, git-annex is configured via `.git/config`.
Here are all the supported configuration settings.

* `annex.uuid`

  A unique UUID for this repository (automatically set).

* `annex.backend`

  Name of the default key-value backend to use when adding new files
  to the repository.

  This is overridden by annex annex.backend configuration in the
  .gitattributes files, and by the --backend option.

  (This used to be named `annex.backends`, and that will still be used
  if set.)

* `annex.securehashesonly`

  Set to true to indicate that the repository should only use
  cryptographically secure hashes
  (SHA2, SHA3) and not insecure hashes (MD5, SHA1) for content.

  When this is set, the contents of files using cryptographically
  insecure hashes will not be allowed to be added to the repository.
  
  Also, git-annex fsck` will complain about any files present in
  the repository that use insecure hashes.
  
  To configure the behavior in new clones of the repository,
  this can be set in [[git-annex-config]].

* `annex.diskreserve`

  Amount of disk space to reserve. Disk space is checked when transferring
  content to avoid running out, and additional free space can be reserved
  via this option, to make space for more important content (such as git
  commit logs). Can be specified with any commonly used units, for example,
  "0.5 gb", "500M", or "100 KiloBytes"

  The default reserve is 1 megabyte.

* `annex.largefiles`

  Used to configure which files are large enough to be added to the annex.
  Default: All files.

  Overrides any annex.largefiles attributes in `.gitattributes` files.

  See <https://git-annex.branchable.com/tips/largefiles> for details.

* `annex.addsmallfiles`

  Controls whether small files (not matching annex.largefiles)
  should be checked into git by `git annex add`. Defaults to true;
  set to false to instead make small files be skipped.

* `annex.addunlocked`

  Set to true to make commands like `git-annex add` that add files to the
  repository add them in unlocked form. The default is to add files in
  locked form. This only has effect in version 6 repositories.

  When a repository has core.symlinks set to false, it implicitly
  sets annex.addunlocked to true.

* `annex.numcopies`

  This is a deprecated setting. You should instead use the
  `git annex numcopies` command to configure how many copies of files
  are kept across all repositories, or the annex.numcopies .gitattributes
  setting.

  This config setting is only looked at when `git annex numcopies` has
  never been configured, and when there's no annex.numcopies setting in the
  .gitattributes file.

  Note that setting numcopies to 0 is very unsafe.

* `annex.genmetadata`

  Set this to `true` to make git-annex automatically generate some metadata
  when adding files to the repository.

  In particular, it stores year, month, and day metadata, from the file's
  modification date.

  When importfeed is used, it stores additional metadata from the feed,
  such as the author, title, etc.

* `annex.used-refspec`

  This controls which refs `git-annex unused` considers to be used.
  See REFSPEC FORMAT in [[git-annex-unused]](1) for details.

* `annex.queuesize`

  git-annex builds a queue of git commands, in order to combine similar
  commands for speed. By default the size of the queue is limited to
  10240 commands; this can be used to change the size. If you have plenty
  of memory and are working with very large numbers of files, increasing
  the queue size can speed it up.

* `annex.bloomcapacity`

  The `git annex unused` and `git annex sync --content` commands use
  a bloom filter to determine what files are present in eg, the work tree.
  The default bloom filter is sized to handle
  up to 500000 files. If your repository is larger than that,
  you should increase this value. Larger values will
  make `git-annex unused` and `git annex sync --content` consume more memory;
  run `git annex info` for memory usage numbers.

* `annex.bloomaccuracy`

  Adjusts the accuracy of the bloom filter used by
  `git annex unused` and `git annex sync --content`. 
  The default accuracy is 10000000 -- 1 unused file out of 10000000
  will be missed by `git annex unused`. Increasing the accuracy will make
  `git annex unused` consume more memory; run `git annex info`
  for memory usage numbers.

* `annex.sshcaching`

  By default, git-annex caches ssh connections using ssh's
  ControlMaster and ControlPersist settings
  (if built using a new enough ssh). To disable this, set to `false`.

* `annex.alwayscommit`

  By default, git-annex automatically commits data to the git-annex branch
  after each command is run. If you have a series
  of commands that you want to make a single commit, you can
  run the commands with `-c annex.alwayscommit=false`. You can later
  commit the data by running `git annex merge` (or by automatic merges)
  or `git annex sync`.

  You should beware running `git gc` when using this configuration,
  since it could garbage collect objects that are staged in git-annex's
  index but not yet committed.

* `annex.merge-annex-branches`

  By default, git-annex branches that have been pulled from remotes
  are automatically merged into the local git-annex branch, so that
  git-annex has the most up-to-date possible knowledge.

  To avoid that merging, set this to "false". This can be useful
  particularly when you don't have write permission to the repository.

* `annex.hardlink`

  Set this to `true` to make file contents be hard linked between the
  repository and its remotes when possible, instead of a more expensive copy.

  Use with caution -- This can invalidate numcopies counting, since
  with hard links, fewer copies of a file can exist. So, it is a good
  idea to mark a repository using this setting as untrusted.

  When a repository is set up using `git clone --shared`, git-annex init
  will automatically set annex.hardlink and mark the repository as
  untrusted.

* `annex.thin`

  Set this to `true` to make unlocked files be a hard link to their content
  in the annex, rather than a second copy. (Only when supported by the file
  system, and only in repository version 6.) This can save considerable
  disk space, but when a modification is made to a file, you will lose the
  local (and possibly only) copy of the old version. So, enable with care.

  After setting (or unsetting) this, you should run `git annex fix` to
  fix up the annexed files in the work tree to be hard links (or copies).

  Note that `annex.thin` is not honored when git updates an annexed file
  in the working tree. So when `git checkout` or `git merge` updates the
  working tree, a second copy of annexed files will result. You can run
  `git-annex fix` to fix up the hard links after running such git commands.

* `annex.delayadd`

  Makes the watch and assistant commands delay for the specified number of
  seconds before adding a newly created file to the annex. Normally this
  is not needed, because they already wait for all writers of the file
  to close it. On Mac OSX, when not using direct mode this defaults to
  1 second, to work around a bad interaction with software there.

* `annex.expireunused`

  Controls what the assistant does about unused file contents
  that are stored in the repository.

  The default is `false`, which causes
  all old and unused file contents to be retained, unless the assistant
  is able to move them to some other repository (such as a backup repository).

  Can be set to a time specification, like "7d" or "1m", and then
  file contents that have been known to be unused for a week or a
  month will be deleted.

* `annex.fscknudge`

  When set to false, prevents the webapp from reminding you when using
  repositories that lack consistency checks.

* `annex.autoupgrade`

  When set to ask (the default), the webapp will check for new versions
  and prompt if they should be upgraded to. When set to true, automatically
  upgrades without prompting (on some supported platforms). When set to
  false, disables any upgrade checking.

  Note that upgrade checking is only done when git-annex is installed
  from one of the prebuilt images from its website. This does not
  bypass e.g., a Linux distribution's own upgrade handling code.

  This setting also controls whether to restart the git-annex assistant
  when the git-annex binary is detected to have changed. That is useful
  no matter how you installed git-annex.

* `annex.autocommit`

  Set to false to prevent the git-annex assistant and git-annex sync
  from automatically committing changes to files in the repository.

  To configure the behavior in all clones of the repository,
  this can be set in [[git-annex-config]].

* `annex.resolvemerge`

  Set to false to prevent merge conflicts in the checked out branch
  being automatically resolved by the git-annex assitant,
  git-annex sync, git-annex merge,
  and the git-annex post-receive hook.

  To configure the behavior in all clones of the repository,
  this can be set in [[git-annex-config]].

* `annex.synccontent`

  Set to true to make git-annex sync default to syncing content.

  To configure the behavior in all clones of the repository,
  this can be set in [[git-annex-config]].

* `annex.startupscan`

  Set to false to prevent the git-annex assistant from scanning the
  repository for new and changed files on startup. This will prevent it
  from noticing changes that were made while it was not running, but can be
  a useful performance tweak for a large repository.

* `annex.listen`

  Configures which address the webapp listens on. The default is localhost.
  Can be either an IP address, or a hostname that resolves to the desired
  address.

* `annex.debug`

  Set to true to enable debug logging by default.

* `annex.version`

  Automatically maintained, and used to automate upgrades between versions.

* `annex.direct`

  Set to true when the repository is in direct mode. Should not be set
  manually; use the "git annex direct" and "git annex indirect" commands
  instead.

* `annex.crippledfilesystem`

  Set to true if the repository is on a crippled filesystem, such as FAT,
  which does not support symbolic links, or hard links, or unix permissions.
  This is automatically probed by "git annex init".

* `annex.pidlock`

  Normally, git-annex uses fine-grained lock files to allow multiple
  processes to run concurrently without getting in each others' way.
  That works great, unless you are using git-annex on a filesystem that
  does not support POSIX fcntl locks. This is sometimes the case when
  using NFS or Lustre filesystems. 
  
  To support such situations, you can set annex.pidlock to true, and it
  will fall back to a single top-level pid file lock.

  Although, often, you'd really be better off fixing your networked
  filesystem configuration to support POSIX locks.. And, some networked
  filesystems are so inconsistent that one node can't reliably tell when
  the other node is holding a pid lock. Caveat emptor.

* `annex.pidlocktimeout`

  When using pid lock files, it's possible for a stale lock file to get
  left behind by previous run of git-annex that crashed or was interrupted.
  This is mostly avoided, but can occur especially when using a network
  file system.

  git-annex will wait up to this many seconds for the pid lock
  file to go away, and will then abort if it cannot continue. Default: 300

* `remote.<name>.annex-cost`

  When determining which repository to
  transfer annexed files from or to, ones with lower costs are preferred.
  The default cost is 100 for local repositories, and 200 for remote
  repositories.

* `remote.<name>.annex-cost-command`

  If set, the command is run, and the number it outputs is used as the cost.
  This allows varying the cost based on e.g., the current network.

* `remote.<name>.annex-start-command`

  A command to run when git-annex begins to use the remote. This can
  be used to, for example, mount the directory containing the remote.

  The command may be run repeatedly when multiple git-annex processes
  are running concurrently.

* `remote.<name>.annex-stop-command`

  A command to run when git-annex is done using the remote.

  The command will only be run once *all* running git-annex processes
  are finished using the remote.

* `remote.<name>.annex-shell`

  Specify an alternative git-annex-shell executable on the remote
  instead of looking for "git-annex-shell" on the PATH.

  This is useful if the git-annex-shell program is outside the PATH
  or has a non-standard name.

* `remote.<name>.annex-ignore`

  If set to `true`, prevents git-annex
  from storing file contents on this remote by default.
  (You can still request it be used by the `--from` and `--to` options.)

  This is, for example, useful if the remote is located somewhere
  without git-annex-shell. (For example, if it's on GitHub).
  Or, it could be used if the network connection between two
  repositories is too slow to be used normally.

  This does not prevent git-annex sync (or the git-annex assistant) from
  syncing the git repository to the remote.

* `remote.<name>.annex-ignore-command`

  If set, the command is run, and if it exits nonzero, that's the same
  as setting annex-ignore to true. This allows controlling behavior based
  on e.g., the current network.

* `remote.<name>.annex-sync`

  If set to `false`, prevents git-annex sync (and the git-annex assistant)
  from syncing with this remote by default. However, `git annex sync <name>`
  can still be used to sync with the remote.

* `remote.<name>.annex-sync-command`

  If set, the command is run, and if it exits nonzero, that's the same
  as setting annex-sync to false. This allows controlling behavior based
  on e.g., the current network.

* `remote.<name>.annex-pull`

  If set to `false`, prevents git-annex sync (and the git-annex assistant
  etc) from ever pulling (or fetching) from the remote.

* `remote.<name>.annex-push`

  If set to `false`, prevents git-annex sync (and the git-annex assistant
  etc) from ever pushing to the remote.

* `remote.<name>.annex-readonly`

  If set to `true`, prevents git-annex from making changes to a remote.
  This both prevents git-annex sync from pushing changes, and prevents
  storing or removing files from read-only remote.

* `remote.<name>.annex-verify`, `annex.verify`

  By default, git-annex will verify the checksums of objects downloaded
  from remotes. If you trust a remote and don't want the overhead
  of these checksums, you can set this to `false`.

* `remote.<name>.annex-export-tracking`

  When set to a branch name or other treeish, this makes what's exported
  to the special remote track changes to the branch. See
  [[git-annex-export]](1). `git-annex sync --content` and the 
  git-annex assistant update exports when changes have been
  committed to the tracking branch.

* `remote.<name>.annexUrl`

  Can be used to specify a different url than the regular `remote.<name>.url`
  for git-annex to use when talking with the remote. Similar to the `pushUrl`
  used by git-push.

* `remote.<name>.annex-uuid`

  git-annex caches UUIDs of remote repositories here.

* `remote.<name>.annex-checkuuid`

  This only affects remotes that have their url pointing to a directory on
  the same system. git-annex normally checks the uuid of such
  remotes each time it's run, which lets it transparently deal with
  different drives being mounted to the location at different times.

  Setting annex-checkuuid to false will prevent it from checking the uuid 
  at startup (although the uuid is still verified before making any
  changes to the remote repository). This may be useful to set to prevent
  unncessary spin-up or automounting of a drive.

* `remote.<name>.annex-trustlevel`

  Configures a local trust level for the remote. This overrides the value
  configured by the trust and untrust commands. The value can be any of
  "trusted", "semitrusted" or "untrusted".

* `remote.<name>.annex-availability`

  Can be used to tell git-annex whether a remote is LocallyAvailable
  or GloballyAvailable. Normally, git-annex determines this automatically.

* `remote.<name>.annex-bare`

  Can be used to tell git-annex if a remote is a bare repository
  or not. Normally, git-annex determines this automatically.

* `remote.<name>.annex-ssh-options`

  Options to use when using ssh to talk to this remote.

* `remote.<name>.annex-rsync-options`

  Options to use when using rsync
  to or from this remote. For example, to force IPv6, and limit
  the bandwidth to 100Kbyte/s, set it to `-6 --bwlimit 100`

  Note that git-annex-shell has a whitelist of allowed rsync options,
  and others will not be be passed to the remote rsync. So using some
  options may break the communication between the local and remote rsyncs.

* `remote.<name>.annex-rsync-upload-options`

  Options to use when using rsync to upload a file to a remote.

  These options are passed after other applicable rsync options,
  so can be used to override them. For example, to limit upload bandwidth
  to 10Kbyte/s, set `--bwlimit 10`.

* `remote.<name>.annex-rsync-download-options`

  Options to use when using rsync to download a file from a remote.

  These options are passed after other applicable rsync options,
  so can be used to override them.

* `remote.<name>.annex-rsync-transport`

  The remote shell to use to connect to the rsync remote. Possible
  values are `ssh` (the default) and `rsh`, together with their
  arguments, for instance `ssh -p 2222 -c blowfish`; Note that the
  remote hostname should not appear there, see rsync(1) for details.
  When the transport used is `ssh`, connections are automatically cached
  unless `annex.sshcaching` is unset.

* `remote.<name>.annex-bup-split-options`

  Options to pass to bup split when storing content in this remote.
  For example, to limit the bandwidth to 100Kbyte/s, set it to `--bwlimit 100k`
  (There is no corresponding option for bup join.)

* `remote.<name>.annex-gnupg-options`

  Options to pass to GnuPG when it's encrypting data. For instance, to
  use the AES cipher with a 256 bits key and disable compression, set it
  to `--cipher-algo AES256 --compress-algo none`. (These options take
  precedence over the default GnuPG configuration, which is otherwise
  used.)

* `remote.<name>.annex-gnupg-decrypt-options`

  Options to pass to GnuPG when it's decrypting data. (These options take
  precedence over the default GnuPG configuration, which is otherwise
  used.)

* `annex.ssh-options`, `annex.rsync-options`,
  `annex.rsync-upload-options`, `annex.rsync-download-options`,
  `annex.bup-split-options`, `annex.gnupg-options`,
  `annex.gnupg-decrypt-options`

  Default options to use if a remote does not have more specific options
  as described above.

* `annex.web-options`

  Options to pass when running wget or curl.
  For example, to force IPv4 only, set it to "-4"

* `annex.youtube-dl-options`

  Options to pass to youtube-dl when using it to find the url to download
  for a video.

  Some options may break git-annex's integration with youtube-dl. For
  example, the --output option could cause it to store files somewhere
  git-annex won't find them. Avoid setting here or in the youtube-dl config
  file any options that cause youtube-dl to download more than one file,
  or to store the file anywhere other than the current working directory.

* `annex.aria-torrent-options`

  Options to pass to aria2c when using it to download a torrent.

* `annex.http-headers`

  HTTP headers to send when downloading from the web. Multiple lines of
  this option can be set, one per header.

* `annex.http-headers-command`

  If set, the command is run and each line of its output is used as a HTTP
  header. This overrides annex.http-headers.

* `annex.web-download-command`

  Use to specify a command to run to download a file from the web.
  (The default is to use wget or curl.)

  In the command line, %url is replaced with the url to download,
  and %file is replaced with the file that it should be saved to.

* `annex.secure-erase-command`

  This can be set to a command that should be run whenever git-annex
  removes the content of a file from the repository.

  In the command line, %file is replaced with the file that should be
  erased.

  For example, to use the wipe command, set it to `wipe -f %file`.

* `remote.<name>.rsyncurl`

  Used by rsync special remotes, this configures
  the location of the rsync repository to use. Normally this is automatically
  set up by `git annex initremote`, but you can change it if needed.

* `remote.<name>.buprepo`

  Used by bup special remotes, this configures
  the location of the bup repository to use. Normally this is automatically
  set up by `git annex initremote`, but you can change it if needed.

* `remote.<name>.ddarrepo`

  Used by ddar special remotes, this configures
  the location of the ddar repository to use. Normally this is automatically
  set up by `git annex initremote`, but you can change it if needed.

* `remote.<name>.directory`

  Used by directory special remotes, this configures
  the location of the directory where annexed files are stored for this
  remote. Normally this is automatically set up by `git annex initremote`,
  but you can change it if needed.

* `remote.<name>.s3`

  Used to identify Amazon S3 special remotes.
  Normally this is automatically set up by `git annex initremote`.

* `remote.<name>.glacier`

  Used to identify Amazon Glacier special remotes.
  Normally this is automatically set up by `git annex initremote`.

* `remote.<name>.webdav`

  Used to identify webdav special remotes.
  Normally this is automatically set up by `git annex initremote`.

* `remote.<name>.tahoe`

  Used to identify tahoe special remotes.
  Points to the configuration directory for tahoe.

* `remote.<name>.gcrypt`

  Used to identify gcrypt special remotes.
  Normally this is automatically set up by `git annex initremote`.

  It is set to "true" if this is a gcrypt remote.
  If the gcrypt remote is accessible over ssh and has git-annex-shell
  available to manage it, it's set to "shell".

* `remote.<name>.hooktype`, `remote.<name>.externaltype`

  Used by hook special remotes and external special remotes to record
  the type of the remote.

* `annex.tune.objecthash1`, `annex.tune.objecthashlower`, `annex.tune.branchhash1`

  These can be passed to `git annex init` to tune the repository.
  They cannot be safely changed in a running repository and should never be
  set in global git configuration.
  For details, see <https://git-annex.branchable.com/tuning/>.

# CONFIGURATION VIA .gitattributes

The key-value backend used when adding a new file to the annex can be
configured on a per-file-type basis via `.gitattributes` files. In the file,
the `annex.backend` attribute can be set to the name of the backend to
use. For example, this here's how to use the WORM backend by default,
but the SHA256E backend for ogg files:

	* annex.backend=WORM
	*.ogg annex.backend=SHA256E

There is a annex.largefiles attribute; which is used to configure which
files are large enough to be added to the annex.
See <https://git-annex.branchable.com/tips/largefiles> for details.

The numcopies setting can also be configured on a per-file-type basis via
the `annex.numcopies` attribute in `.gitattributes` files. This overrides
other numcopies settings.
For example, this makes two copies be needed for wav files and 3 copies
for flac files:

	*.wav annex.numcopies=2
	*.flac annex.numcopies=3

Note that setting numcopies to 0 is very unsafe.

These settings are honored by git-annex whenever it's operating on a
matching file. However, when using --all, --unused, or --key to specify
keys to operate on, git-annex is operating on keys and not files, so will
not honor the settings from .gitattributes. For this reason, the `git annex
numcopies` command is useful to configure a global default for numcopies.

Also note that when using views, only the toplevel .gitattributes file is
preserved in the view, so other settings in other files won't have any
effect.

# EXIT STATUS

git-annex, when called as a git subcommand, may return exit codes 0 or 1
for success or failures, or, more rarely, 127 or 128 for certain very
specific failures.  git-annex itself should return 0 on success and 1 on
failure, unless the `--time-limit=time` option is hit, in which case it
returns with exit code 101.

# ENVIRONMENT

These environment variables are used by git-annex when set:

* `GIT_WORK_TREE`, `GIT_DIR`

  Handled the same as they are by git, see git(1)

* `GIT_SSH`, `GIT_SSH_COMMAND`

  Handled similarly to the same as described in git(1).
  The one difference is that git-annex will sometimes pass an additional
  "-n" parameter to these, as the first parameter, to prevent ssh from
  reading from stdin. Since that can break existing uses of these
  environment variables that don't expect the extra parameter, you will
  need to set `GIT_ANNEX_USE_GIT_SSH=1` to make git-annex support
  these.

  Note that setting either of these environment variables prevents
  git-annex from automatically enabling ssh connection caching
  (see `annex.sshcaching`), so it will slow down some operations with
  remotes over ssh. It's up to you to enable ssh connection caching
  if you need it; see ssh's documentation.

  Also, `annex.ssh-options` and `remote.<name>.annex-ssh-options`
  won't have any effect when these envionment variables are set.

  Usually it's better to configure any desired options through your
  ~/.ssh/config file, or by setting `annex.ssh-options`.

* `GIT_ANNEX_VECTOR_CLOCK`

  Normally git-annex timestamps lines in the log files committed to the
  git-annex branch. Setting this environment variable to a number
  will make git-annex use that rather than the current number of seconds
  since the UNIX epoch. Note that decimal seconds are supported.
  
  This is only provided for advanced users who either have a better way to
  tell which commit is current than the local clock, or who need to avoid
  embedding timestamps for policy reasons. Misuse of this environment
  variable can confuse git-annex's book-keeping, sometimes in ways that
  `git annex fsck` is unable to repair.

Some special remotes use additional environment variables
for authentication etc. For example, `AWS_ACCESS_KEY_ID`
and `GIT_ANNEX_P2P_AUTHTOKEN`. See special remote documentation.

# FILES

These files are used by git-annex:

`.git/annex/objects/` in your git repository contains the annexed file
contents that are currently available. Annexed files in your git
repository symlink to that content.

`.git/annex/` in your git repository contains other run-time information
used by git-annex.

`~/.config/git-annex/autostart` is a list of git repositories
to start the git-annex assistant in.

`.git/hooks/pre-commit-annex` in your git repository will be run whenever
a commit is made to the HEAD branch, either by git commit, git-annex
sync, or the git-annex assistant.

`.git/hooks/post-update-annex` in your git repository will be run
whenever the git-annex branch is updated. You can make this hook run
`git update-server-info` when publishing a git-annex repository by http.

# SEE ALSO

More git-annex documentation is available on its web site,
<https://git-annex.branchable.com/>

If git-annex is installed from a package, a copy of its documentation
should be included, in, for example, `/usr/share/doc/git-annex/`.

# AUTHOR

Joey Hess <id@joeyh.name>

<https://git-annex.branchable.com/>

Warning: Automatically converted into a man page by mdwn2man. Edit with care.