git-update-index(1) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | USING --REFRESH | USING --CACHEINFO OR --INFO-ONLY | USING --INDEX-INFO | USING “ASSUME UNCHANGED” BIT | EXAMPLES | SKIP-WORKTREE BIT | SPLIT INDEX | UNTRACKED CACHE | FILE SYSTEM MONITOR | CONFIGURATION | NOTES | SEE ALSO | GIT | COLOPHON

GIT-UPDATE-INDEX(1)            Git Manual            GIT-UPDATE-INDEX(1)

NAME         top

       git-update-index - Register file contents in the working tree to
       the index

SYNOPSIS         top

       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>]
                    [--verbose]
                    [--] [<file>...]

DESCRIPTION         top

       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:

OPTIONS         top

       --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 file.

       --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 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 name
           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 name
           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 from 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 list of paths from the command line, read
           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 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.

           Version 4 performs a simple pathname compression that reduces
           index size by 30%-50% on large repositories, which results in
           faster load time. Version 4 is relatively young (first
           released in 1.8.0 in October 2012). Other Git implementations
           such as JGit and libgit2 may not support it yet.

       -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 //

USING --REFRESH         top

       --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.

USING --CACHEINFO OR --INFO-ONLY         top

       --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.

USING --INDEX-INFO         top

       --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

USING “ASSUME UNCHANGED” BIT         top

       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").

EXAMPLES         top

       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         top

       Skip-worktree bit can be defined in one (long) sentence: When
       reading an entry, if it is marked as skip-worktree, then Git
       pretends its working directory version is up to date and read the
       index version instead.

       To elaborate, "reading" means checking for file existence,
       reading file attributes or file content. The working directory
       version may be present or absent. If present, its content may
       match against the index version or not. Writing is not affected
       by this bit, content safety is still first priority. Note that
       Git can update working directory file, that is marked
       skip-worktree, if it is safe to do so (i.e. working directory
       version matches index version)

       Although this bit looks similar to assume-unchanged bit, its goal
       is different from assume-unchanged bit’s. Skip-worktree also
       takes precedence over assume-unchanged bit when both are set.

SPLIT INDEX         top

       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.

UNTRACKED CACHE         top

       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.

FILE SYSTEM MONITOR         top

       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
       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.

CONFIGURATION         top

       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)).

NOTES         top

       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.

SEE ALSO         top

       git-config(1), git-add(1), git-ls-files(1)

GIT         top

       Part of the git(1) suite

COLOPHON         top

       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 2021-04-01.  (At that time,
       the date of the most recent commit that was found in the
       repository was 2021-03-30.)  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
       man-pages@man7.org

Git 2.31.1.163.ga65ce7         04/01/2021            GIT-UPDATE-INDEX(1)

Pages that refer to this page: git(1)git-add(1)git-config(1)git-filter-branch(1)git-ls-files(1)git-read-tree(1)git-sparse-checkout(1)