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GIT-UPDATE-INDEX(1) Git Manual GIT-UPDATE-INDEX(1)
git-update-index - Register file contents in the working tree to
the index
git update-index
[--add] [--remove | --force-remove] [--replace]
[--refresh] [-q] [--unmerged] [--ignore-missing]
[(--cacheinfo <mode>,<object>,<file>)...]
[--chmod=(+|-)x]
[--[no-]assume-unchanged]
[--[no-]skip-worktree]
[--[no-]ignore-skip-worktree-entries]
[--[no-]fsmonitor-valid]
[--ignore-submodules]
[--[no-]split-index]
[--[no-|test-|force-]untracked-cache]
[--[no-]fsmonitor]
[--really-refresh] [--unresolve] [--again | -g]
[--info-only] [--index-info]
[-z] [--stdin] [--index-version <n>]
[--show-index-version]
[--verbose]
[--] [<file>...]
Modifies the index. Each file mentioned is updated into the index
and any unmerged or needs updating state is cleared.
See also git-add(1) for a more user-friendly way to do some of
the most common operations on the index.
The way git update-index handles files it is told about can be
modified using the various options:
--add
If a specified file isn’t in the index already then it’s
added. Default behaviour is to ignore new files.
--remove
If a specified file is in the index but is missing then it’s
removed. Default behavior is to ignore removed files.
--refresh
Looks at the current index and checks to see if merges or
updates are needed by checking stat() information.
-q
Quiet. If --refresh finds that the index needs an update, the
default behavior is to error out. This option makes git
update-index continue anyway.
--ignore-submodules
Do not try to update submodules. This option is only
respected when passed before --refresh.
--unmerged
If --refresh finds unmerged changes in the index, the default
behavior is to error out. This option makes git update-index
continue anyway.
--ignore-missing
Ignores missing files during a --refresh
--cacheinfo <mode>,<object>,<path>, --cacheinfo <mode> <object>
<path>
Directly insert the specified info into the index. For
backward compatibility, you can also give these three
arguments as three separate parameters, but new users are
encouraged to use a single-parameter form.
--index-info
Read index information from stdin.
--chmod=(+|-)x
Set the execute permissions on the updated files.
--[no-]assume-unchanged
When this flag is specified, the object names recorded for
the paths are not updated. Instead, this option sets/unsets
the "assume unchanged" bit for the paths. When the "assume
unchanged" bit is on, the user promises not to change the
file and allows Git to assume that the working tree file
matches what is recorded in the index. If you want to change
the working tree file, you need to unset the bit to tell Git.
This is sometimes helpful when working with a big project on
a filesystem that has a very slow lstat(2) system call (e.g.
cifs).
Git will fail (gracefully) in case it needs to modify this
file in the index e.g. when merging in a commit; thus, in
case the assumed-untracked file is changed upstream, you will
need to handle the situation manually.
--really-refresh
Like --refresh, but checks stat information unconditionally,
without regard to the "assume unchanged" setting.
--[no-]skip-worktree
When one of these flags is specified, the object names
recorded for the paths are not updated. Instead, these
options set and unset the "skip-worktree" bit for the paths.
See section "Skip-worktree bit" below for more information.
--[no-]ignore-skip-worktree-entries
Do not remove skip-worktree (AKA "index-only") entries even
when the --remove option was specified.
--[no-]fsmonitor-valid
When one of these flags is specified, the object names
recorded for the paths are not updated. Instead, these
options set and unset the "fsmonitor valid" bit for the
paths. See section "File System Monitor" below for more
information.
-g, --again
Runs git update-index itself on the paths whose index entries
are different from those of the HEAD commit.
--unresolve
Restores the unmerged or needs updating state of a file
during a merge if it was cleared by accident.
--info-only
Do not create objects in the object database for all <file>
arguments that follow this flag; just insert their object IDs
into the index.
--force-remove
Remove the file from the index even when the working
directory still has such a file. (Implies --remove.)
--replace
By default, when a file path exists in the index, git
update-index refuses an attempt to add path/file. Similarly
if a file path/file exists, a file path cannot be added. With
--replace flag, existing entries that conflict with the entry
being added are automatically removed with warning messages.
--stdin
Instead of taking a list of paths from the command line, read
a list of paths from the standard input. Paths are separated
by LF (i.e. one path per line) by default.
--verbose
Report what is being added and removed from the index.
--index-version <n>
Write the resulting index out in the named on-disk format
version. Supported versions are 2, 3, and 4. The current
default version is 2 or 3, depending on whether extra
features are used, such as git add -N. With --verbose, also
report the version the index file uses before and after this
command.
Version 4 performs a simple pathname compression that reduces
index size by 30%-50% on large repositories, which results in
faster load time. Git supports it since version 1.8.0,
released in October 2012, and support for it was added to
libgit2 in 2016 and to JGit in 2020. Older versions of this
manual page called it "relatively young", but it should be
considered mature technology these days.
--show-index-version
Report the index format version used by the on-disk index
file. See --index-version above.
-z
Only meaningful with --stdin or --index-info; paths are
separated with NUL character instead of LF.
--split-index, --no-split-index
Enable or disable split index mode. If split-index mode is
already enabled and --split-index is given again, all changes
in $GIT_DIR/index are pushed back to the shared index file.
These options take effect whatever the value of the
core.splitIndex configuration variable (see git-config(1)).
But a warning is emitted when the change goes against the
configured value, as the configured value will take effect
next time the index is read and this will remove the intended
effect of the option.
--untracked-cache, --no-untracked-cache
Enable or disable untracked cache feature. Please use
--test-untracked-cache before enabling it.
These options take effect whatever the value of the
core.untrackedCache configuration variable (see
git-config(1)). But a warning is emitted when the change goes
against the configured value, as the configured value will
take effect next time the index is read and this will remove
the intended effect of the option.
--test-untracked-cache
Only perform tests on the working directory to make sure
untracked cache can be used. You have to manually enable
untracked cache using --untracked-cache or
--force-untracked-cache or the core.untrackedCache
configuration variable afterwards if you really want to use
it. If a test fails the exit code is 1 and a message explains
what is not working as needed, otherwise the exit code is 0
and OK is printed.
--force-untracked-cache
Same as --untracked-cache. Provided for backwards
compatibility with older versions of Git where
--untracked-cache used to imply --test-untracked-cache but
this option would enable the extension unconditionally.
--fsmonitor, --no-fsmonitor
Enable or disable files system monitor feature. These options
take effect whatever the value of the core.fsmonitor
configuration variable (see git-config(1)). But a warning is
emitted when the change goes against the configured value, as
the configured value will take effect next time the index is
read and this will remove the intended effect of the option.
--
Do not interpret any more arguments as options.
<file>
Files to act on. Note that files beginning with . are
discarded. This includes ./file and dir/./file. If you don’t
want this, then use cleaner names. The same applies to
directories ending / and paths with //
--refresh does not calculate a new sha1 file or bring the index
up to date for mode/content changes. But what it does do is to
"re-match" the stat information of a file with the index, so that
you can refresh the index for a file that hasn’t been changed but
where the stat entry is out of date.
For example, you’d want to do this after doing a git read-tree,
to link up the stat index details with the proper files.
--cacheinfo is used to register a file that is not in the current
working directory. This is useful for minimum-checkout merging.
To pretend you have a file at path with mode and sha1, say:
$ git update-index --add --cacheinfo <mode>,<sha1>,<path>
--info-only is used to register files without placing them in the
object database. This is useful for status-only repositories.
Both --cacheinfo and --info-only behave similarly: the index is
updated but the object database isn’t. --cacheinfo is useful when
the object is in the database but the file isn’t available
locally. --info-only is useful when the file is available, but
you do not wish to update the object database.
--index-info is a more powerful mechanism that lets you feed
multiple entry definitions from the standard input, and designed
specifically for scripts. It can take inputs of three formats:
1. mode SP type SP sha1 TAB path
This format is to stuff git ls-tree output into the index.
2. mode SP sha1 SP stage TAB path
This format is to put higher order stages into the index file
and matches git ls-files --stage output.
3. mode SP sha1 TAB path
This format is no longer produced by any Git command, but is
and will continue to be supported by update-index
--index-info.
To place a higher stage entry to the index, the path should first
be removed by feeding a mode=0 entry for the path, and then
feeding necessary input lines in the third format.
For example, starting with this index:
$ git ls-files -s
100644 8a1218a1024a212bb3db30becd860315f9f3ac52 0 frotz
you can feed the following input to --index-info:
$ git update-index --index-info
0 0000000000000000000000000000000000000000 frotz
100644 8a1218a1024a212bb3db30becd860315f9f3ac52 1 frotz
100755 8a1218a1024a212bb3db30becd860315f9f3ac52 2 frotz
The first line of the input feeds 0 as the mode to remove the
path; the SHA-1 does not matter as long as it is well formatted.
Then the second and third line feeds stage 1 and stage 2 entries
for that path. After the above, we would end up with this:
$ git ls-files -s
100644 8a1218a1024a212bb3db30becd860315f9f3ac52 1 frotz
100755 8a1218a1024a212bb3db30becd860315f9f3ac52 2 frotz
Many operations in Git depend on your filesystem to have an
efficient lstat(2) implementation, so that st_mtime information
for working tree files can be cheaply checked to see if the file
contents have changed from the version recorded in the index
file. Unfortunately, some filesystems have inefficient lstat(2).
If your filesystem is one of them, you can set "assume unchanged"
bit to paths you have not changed to cause Git not to do this
check. Note that setting this bit on a path does not mean Git
will check the contents of the file to see if it has changed — it
makes Git to omit any checking and assume it has not changed.
When you make changes to working tree files, you have to
explicitly tell Git about it by dropping "assume unchanged" bit,
either before or after you modify them.
In order to set "assume unchanged" bit, use --assume-unchanged
option. To unset, use --no-assume-unchanged. To see which files
have the "assume unchanged" bit set, use git ls-files -v (see
git-ls-files(1)).
The command looks at core.ignorestat configuration variable. When
this is true, paths updated with git update-index paths... and
paths updated with other Git commands that update both index and
working tree (e.g. git apply --index, git checkout-index -u, and
git read-tree -u) are automatically marked as "assume unchanged".
Note that "assume unchanged" bit is not set if git update-index
--refresh finds the working tree file matches the index (use git
update-index --really-refresh if you want to mark them as "assume
unchanged").
Sometimes users confuse the assume-unchanged bit with the
skip-worktree bit. See the final paragraph in the "Skip-worktree
bit" section below for an explanation of the differences.
To update and refresh only the files already checked out:
$ git checkout-index -n -f -a && git update-index --ignore-missing --refresh
On an inefficient filesystem with core.ignorestat set
$ git update-index --really-refresh (1)
$ git update-index --no-assume-unchanged foo.c (2)
$ git diff --name-only (3)
$ edit foo.c
$ git diff --name-only (4)
M foo.c
$ git update-index foo.c (5)
$ git diff --name-only (6)
$ edit foo.c
$ git diff --name-only (7)
$ git update-index --no-assume-unchanged foo.c (8)
$ git diff --name-only (9)
M foo.c
1. forces lstat(2) to set "assume unchanged" bits for
paths that match index.
2. mark the path to be edited.
3. this does lstat(2) and finds index matches the path.
4. this does lstat(2) and finds index does not match the
path.
5. registering the new version to index sets "assume
unchanged" bit.
6. and it is assumed unchanged.
7. even after you edit it.
8. you can tell about the change after the fact.
9. now it checks with lstat(2) and finds it has been
changed.
Skip-worktree bit can be defined in one (long) sentence: Tell git
to avoid writing the file to the working directory when
reasonably possible, and treat the file as unchanged when it is
not present in the working directory.
Note that not all git commands will pay attention to this bit,
and some only partially support it.
The update-index flags and the read-tree capabilities relating to
the skip-worktree bit predated the introduction of the
git-sparse-checkout(1) command, which provides a much easier way
to configure and handle the skip-worktree bits. If you want to
reduce your working tree to only deal with a subset of the files
in the repository, we strongly encourage the use of
git-sparse-checkout(1) in preference to the low-level
update-index and read-tree primitives.
The primary purpose of the skip-worktree bit is to enable sparse
checkouts, i.e. to have working directories with only a subset of
paths present. When the skip-worktree bit is set, Git commands
(such as switch, pull, merge) will avoid writing these files.
However, these commands will sometimes write these files anyway
in important cases such as conflicts during a merge or rebase.
Git commands will also avoid treating the lack of such files as
an intentional deletion; for example git add -u will not stage a
deletion for these files and git commit -a will not make a commit
deleting them either.
Although this bit looks similar to assume-unchanged bit, its goal
is different. The assume-unchanged bit is for leaving the file in
the working tree but having Git omit checking it for changes and
presuming that the file has not been changed (though if it can
determine without stat’ing the file that it has changed, it is
free to record the changes). skip-worktree tells Git to ignore
the absence of the file, avoid updating it when possible with
commands that normally update much of the working directory (e.g.
checkout, switch, pull, etc.), and not have its absence be
recorded in commits. Note that in sparse checkouts (setup by git
sparse-checkout or by configuring core.sparseCheckout to true),
if a file is marked as skip-worktree in the index but is found in
the working tree, Git will clear the skip-worktree bit for that
file.
This mode is designed for repositories with very large indexes,
and aims at reducing the time it takes to repeatedly write these
indexes.
In this mode, the index is split into two files, $GIT_DIR/index
and $GIT_DIR/sharedindex.<SHA-1>. Changes are accumulated in
$GIT_DIR/index, the split index, while the shared index file
contains all index entries and stays unchanged.
All changes in the split index are pushed back to the shared
index file when the number of entries in the split index reaches
a level specified by the splitIndex.maxPercentChange config
variable (see git-config(1)).
Each time a new shared index file is created, the old shared
index files are deleted if their modification time is older than
what is specified by the splitIndex.sharedIndexExpire config
variable (see git-config(1)).
To avoid deleting a shared index file that is still used, its
modification time is updated to the current time every time a new
split index based on the shared index file is either created or
read from.
This cache is meant to speed up commands that involve determining
untracked files such as git status.
This feature works by recording the mtime of the working tree
directories and then omitting reading directories and stat calls
against files in those directories whose mtime hasn’t changed.
For this to work the underlying operating system and file system
must change the st_mtime field of directories if files in the
directory are added, modified or deleted.
You can test whether the filesystem supports that with the
--test-untracked-cache option. The --untracked-cache option used
to implicitly perform that test in older versions of Git, but
that’s no longer the case.
If you want to enable (or disable) this feature, it is easier to
use the core.untrackedCache configuration variable (see
git-config(1)) than using the --untracked-cache option to git
update-index in each repository, especially if you want to do so
across all repositories you use, because you can set the
configuration variable to true (or false) in your
$HOME/.gitconfig just once and have it affect all repositories
you touch.
When the core.untrackedCache configuration variable is changed,
the untracked cache is added to or removed from the index the
next time a command reads the index; while when
--[no-|force-]untracked-cache are used, the untracked cache is
immediately added to or removed from the index.
Before 2.17, the untracked cache had a bug where replacing a
directory with a symlink to another directory could cause it to
incorrectly show files tracked by git as untracked. See the
"status: add a failing test showing a core.untrackedCache bug"
commit to git.git. A workaround for that is (and this might work
for other undiscovered bugs in the future):
$ git -c core.untrackedCache=false status
This bug has also been shown to affect non-symlink cases of
replacing a directory with a file when it comes to the internal
structures of the untracked cache, but no case has been reported
where this resulted in wrong "git status" output.
There are also cases where existing indexes written by git
versions before 2.17 will reference directories that don’t exist
anymore, potentially causing many "could not open directory"
warnings to be printed on "git status". These are new warnings
for existing issues that were previously silently discarded.
As with the bug described above the solution is to one-off do a
"git status" run with core.untrackedCache=false to flush out the
leftover bad data.
This feature is intended to speed up git operations for repos
that have large working directories.
It enables git to work together with a file system monitor (see
git-fsmonitor--daemon(1) and the "fsmonitor-watchman" section of
githooks(5)) that can inform it as to what files have been
modified. This enables git to avoid having to lstat() every file
to find modified files.
When used in conjunction with the untracked cache, it can further
improve performance by avoiding the cost of scanning the entire
working directory looking for new files.
If you want to enable (or disable) this feature, it is easier to
use the core.fsmonitor configuration variable (see git-config(1))
than using the --fsmonitor option to git update-index in each
repository, especially if you want to do so across all
repositories you use, because you can set the configuration
variable in your $HOME/.gitconfig just once and have it affect
all repositories you touch.
When the core.fsmonitor configuration variable is changed, the
file system monitor is added to or removed from the index the
next time a command reads the index. When --[no-]fsmonitor are
used, the file system monitor is immediately added to or removed
from the index.
The command honors core.filemode configuration variable. If your
repository is on a filesystem whose executable bits are
unreliable, this should be set to false (see git-config(1)). This
causes the command to ignore differences in file modes recorded
in the index and the file mode on the filesystem if they differ
only on executable bit. On such an unfortunate filesystem, you
may need to use git update-index --chmod=.
Quite similarly, if core.symlinks configuration variable is set
to false (see git-config(1)), symbolic links are checked out as
plain files, and this command does not modify a recorded file
mode from symbolic link to regular file.
The command looks at core.ignorestat configuration variable. See
Using "assume unchanged" bit section above.
The command also looks at core.trustctime configuration variable.
It can be useful when the inode change time is regularly modified
by something outside Git (file system crawlers and backup systems
use ctime for marking files processed) (see git-config(1)).
The untracked cache extension can be enabled by the
core.untrackedCache configuration variable (see git-config(1)).
Users often try to use the assume-unchanged and skip-worktree
bits to tell Git to ignore changes to files that are tracked.
This does not work as expected, since Git may still check working
tree files against the index when performing certain operations.
In general, Git does not provide a way to ignore changes to
tracked files, so alternate solutions are recommended.
For example, if the file you want to change is some sort of
config file, the repository can include a sample config file that
can then be copied into the ignored name and modified. The
repository can even include a script to treat the sample file as
a template, modifying and copying it automatically.
git-config(1), git-add(1), git-ls-files(1)
Part of the git(1) suite
This page is part of the git (Git distributed version control
system) project. Information about the project can be found at
⟨http://git-scm.com/⟩. If you have a bug report for this manual
page, see ⟨http://git-scm.com/community⟩. This page was obtained
from the project's upstream Git repository
⟨https://github.com/git/git.git⟩ on 2024-06-14. (At that time,
the date of the most recent commit that was found in the
repository was 2024-06-12.) If you discover any rendering
problems in this HTML version of the page, or you believe there
is a better or more up-to-date source for the page, or you have
corrections or improvements to the information in this COLOPHON
(which is not part of the original manual page), send a mail to
[email protected]
Git 2.45.2.492.gd63586 2024-06-12 GIT-UPDATE-INDEX(1)
Pages that refer to this page: git(1), git-add(1), git-config(1), git-filter-branch(1), git-fsmonitor--daemon(1), git-ls-files(1), git-read-tree(1), git-sparse-checkout(1), git-status(1)
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HTML rendering created 2024-06-26 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
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