Documentation/git-update-index.txt

   1 git-update-index(1)
   2 ===================
   3
   4 NAME
   5 ----
   6 git-update-index - Register file contents in the working tree to the index
   7
   8
   9 SYNOPSIS
  10 --------
  11 [verse]
  12 'git update-index'
  13              [--add] [--remove | --force-remove] [--replace]
  14              [--refresh] [-q] [--unmerged] [--ignore-missing]
  15              [(--cacheinfo <mode>,<object>,<file>)...]
  16              [--chmod=(+|-)x]
  17              [--[no-]assume-unchanged]
  18              [--[no-]skip-worktree]
  19              [--ignore-submodules]
  20              [--[no-]split-index]
  21              [--[no-|test-|force-]untracked-cache]
  22              [--really-refresh] [--unresolve] [--again | -g]
  23              [--info-only] [--index-info]
  24              [-z] [--stdin] [--index-version <n>]
  25              [--verbose]
  26              [--] [<file>...]
  27
  28 DESCRIPTION
  29 -----------
  30 Modifies the index or directory cache. Each file mentioned is updated
  31 into the index and any 'unmerged' or 'needs updating' state is
  32 cleared.
  33
  34 See also linkgit:git-add[1] for a more user-friendly way to do some of
  35 the most common operations on the index.
  36
  37 The way 'git update-index' handles files it is told about can be modified
  38 using the various options:
  39
  40 OPTIONS
  41 -------
  42 --add::
  43         If a specified file isn't in the index already then it's
  44         added.
  45         Default behaviour is to ignore new files.
  46
  47 --remove::
  48         If a specified file is in the index but is missing then it's
  49         removed.
  50         Default behavior is to ignore removed file.
  51
  52 --refresh::
  53         Looks at the current index and checks to see if merges or
  54         updates are needed by checking stat() information.
  55
  56 -q::
  57         Quiet.  If --refresh finds that the index needs an update, the
  58         default behavior is to error out.  This option makes
  59         'git update-index' continue anyway.
  60
  61 --ignore-submodules::
  62         Do not try to update submodules.  This option is only respected
  63         when passed before --refresh.
  64
  65 --unmerged::
  66         If --refresh finds unmerged changes in the index, the default
  67         behavior is to error out.  This option makes 'git update-index'
  68         continue anyway.
  69
  70 --ignore-missing::
  71         Ignores missing files during a --refresh
  72
  73 --cacheinfo <mode>,<object>,<path>::
  74 --cacheinfo <mode> <object> <path>::
  75         Directly insert the specified info into the index.  For
  76         backward compatibility, you can also give these three
  77         arguments as three separate parameters, but new users are
  78         encouraged to use a single-parameter form.
  79
  80 --index-info::
  81         Read index information from stdin.
  82
  83 --chmod=(+|-)x::
  84         Set the execute permissions on the updated files.
  85
  86 --[no-]assume-unchanged::
  87         When this flag is specified, the object names recorded
  88         for the paths are not updated.  Instead, this option
  89         sets/unsets the "assume unchanged" bit for the
  90         paths.  When the "assume unchanged" bit is on, the user
  91         promises not to change the file and allows Git to assume
  92         that the working tree file matches what is recorded in
  93         the index.  If you want to change the working tree file,
  94         you need to unset the bit to tell Git.  This is
  95         sometimes helpful when working with a big project on a
  96         filesystem that has very slow lstat(2) system call
  97         (e.g. cifs).
  98 +
  99 Git will fail (gracefully) in case it needs to modify this file
 100 in the index e.g. when merging in a commit;
 101 thus, in case the assumed-untracked file is changed upstream,
 102 you will need to handle the situation manually.
 103
 104 --really-refresh::
 105         Like '--refresh', but checks stat information unconditionally,
 106         without regard to the "assume unchanged" setting.
 107
 108 --[no-]skip-worktree::
 109         When one of these flags is specified, the object name recorded
 110         for the paths are not updated. Instead, these options
 111         set and unset the "skip-worktree" bit for the paths. See
 112         section "Skip-worktree bit" below for more information.
 113
 114 -g::
 115 --again::
 116         Runs 'git update-index' itself on the paths whose index
 117         entries are different from those from the `HEAD` commit.
 118
 119 --unresolve::
 120         Restores the 'unmerged' or 'needs updating' state of a
 121         file during a merge if it was cleared by accident.
 122
 123 --info-only::
 124         Do not create objects in the object database for all
 125         <file> arguments that follow this flag; just insert
 126         their object IDs into the index.
 127
 128 --force-remove::
 129         Remove the file from the index even when the working directory
 130         still has such a file. (Implies --remove.)
 131
 132 --replace::
 133         By default, when a file `path` exists in the index,
 134         'git update-index' refuses an attempt to add `path/file`.
 135         Similarly if a file `path/file` exists, a file `path`
 136         cannot be added.  With --replace flag, existing entries
 137         that conflict with the entry being added are
 138         automatically removed with warning messages.
 139
 140 --stdin::
 141         Instead of taking list of paths from the command line,
 142         read list of paths from the standard input.  Paths are
 143         separated by LF (i.e. one path per line) by default.
 144
 145 --verbose::
 146         Report what is being added and removed from index.
 147
 148 --index-version <n>::
 149         Write the resulting index out in the named on-disk format version.
 150         Supported versions are 2, 3 and 4. The current default version is 2
 151         or 3, depending on whether extra features are used, such as
 152         `git add -N`.
 153 +
 154 Version 4 performs a simple pathname compression that reduces index
 155 size by 30%-50% on large repositories, which results in faster load
 156 time. Version 4 is relatively young (first released in in 1.8.0 in
 157 October 2012). Other Git implementations such as JGit and libgit2
 158 may not support it yet.
 159
 160 -z::
 161         Only meaningful with `--stdin` or `--index-info`; paths are
 162         separated with NUL character instead of LF.
 163
 164 --split-index::
 165 --no-split-index::
 166         Enable or disable split index mode. If enabled, the index is
 167         split into two files, $GIT_DIR/index and $GIT_DIR/sharedindex.<SHA-1>.
 168         Changes are accumulated in $GIT_DIR/index while the shared
 169         index file contains all index entries stays unchanged. If
 170         split-index mode is already enabled and `--split-index` is
 171         given again, all changes in $GIT_DIR/index are pushed back to
 172         the shared index file. This mode is designed for very large
 173         indexes that take a significant amount of time to read or write.
 174
 175 --untracked-cache::
 176 --no-untracked-cache::
 177         Enable or disable untracked cache extension. This could speed
 178         up for commands that involve determining untracked files such
 179         as `git status`. The underlying operating system and file
 180         system must change `st_mtime` field of a directory if files
 181         are added or deleted in that directory.
 182
 183 --test-untracked-cache::
 184         Only perform tests on the working directory to make sure
 185         untracked cache can be used. You have to manually enable
 186         untracked cache using `--force-untracked-cache` (or
 187         `--untracked-cache` but this will run the tests again)
 188         afterwards if you really want to use it. If a test fails
 189         the exit code is 1 and a message explains what is not
 190         working as needed, otherwise the exit code is 0 and OK is
 191         printed.
 192
 193 --force-untracked-cache::
 194         For safety, `--untracked-cache` performs tests on the working
 195         directory to make sure untracked cache can be used. These
 196         tests can take a few seconds. `--force-untracked-cache` can be
 197         used to skip the tests.
 198
 199 \--::
 200         Do not interpret any more arguments as options.
 201
 202 <file>::
 203         Files to act on.
 204         Note that files beginning with '.' are discarded. This includes
 205         `./file` and `dir/./file`. If you don't want this, then use
 206         cleaner names.
 207         The same applies to directories ending '/' and paths with '//'
 208
 209 Using --refresh
 210 ---------------
 211 '--refresh' does not calculate a new sha1 file or bring the index
 212 up-to-date for mode/content changes. But what it *does* do is to
 213 "re-match" the stat information of a file with the index, so that you
 214 can refresh the index for a file that hasn't been changed but where
 215 the stat entry is out of date.
 216
 217 For example, you'd want to do this after doing a 'git read-tree', to link
 218 up the stat index details with the proper files.
 219
 220 Using --cacheinfo or --info-only
 221 --------------------------------
 222 '--cacheinfo' is used to register a file that is not in the
 223 current working directory.  This is useful for minimum-checkout
 224 merging.
 225
 226 To pretend you have a file with mode and sha1 at path, say:
 227
 228 ----------------
 229 $ git update-index --cacheinfo <mode>,<sha1>,<path>
 230 ----------------
 231
 232 '--info-only' is used to register files without placing them in the object
 233 database.  This is useful for status-only repositories.
 234
 235 Both '--cacheinfo' and '--info-only' behave similarly: the index is updated
 236 but the object database isn't.  '--cacheinfo' is useful when the object is
 237 in the database but the file isn't available locally.  '--info-only' is
 238 useful when the file is available, but you do not wish to update the
 239 object database.
 240
 241
 242 Using --index-info
 243 ------------------
 244
 245 `--index-info` is a more powerful mechanism that lets you feed
 246 multiple entry definitions from the standard input, and designed
 247 specifically for scripts.  It can take inputs of three formats:
 248
 249     . mode         SP sha1          TAB path
 250 +
 251 The first format is what "git-apply --index-info"
 252 reports, and used to reconstruct a partial tree
 253 that is used for phony merge base tree when falling
 254 back on 3-way merge.
 255
 256     . mode SP type SP sha1          TAB path
 257 +
 258 The second format is to stuff 'git ls-tree' output
 259 into the index file.
 260
 261     . mode         SP sha1 SP stage TAB path
 262 +
 263 This format is to put higher order stages into the
 264 index file and matches 'git ls-files --stage' output.
 265
 266 To place a higher stage entry to the index, the path should
 267 first be removed by feeding a mode=0 entry for the path, and
 268 then feeding necessary input lines in the third format.
 269
 270 For example, starting with this index:
 271
 272 ------------
 273 $ git ls-files -s
 274 100644 8a1218a1024a212bb3db30becd860315f9f3ac52 0       frotz
 275 ------------
 276
 277 you can feed the following input to `--index-info`:
 278
 279 ------------
 280 $ git update-index --index-info
 281 0 0000000000000000000000000000000000000000      frotz
 282 100644 8a1218a1024a212bb3db30becd860315f9f3ac52 1       frotz
 283 100755 8a1218a1024a212bb3db30becd860315f9f3ac52 2       frotz
 284 ------------
 285
 286 The first line of the input feeds 0 as the mode to remove the
 287 path; the SHA-1 does not matter as long as it is well formatted.
 288 Then the second and third line feeds stage 1 and stage 2 entries
 289 for that path.  After the above, we would end up with this:
 290
 291 ------------
 292 $ git ls-files -s
 293 100644 8a1218a1024a212bb3db30becd860315f9f3ac52 1       frotz
 294 100755 8a1218a1024a212bb3db30becd860315f9f3ac52 2       frotz
 295 ------------
 296
 297
 298 Using ``assume unchanged'' bit
 299 ------------------------------
 300
 301 Many operations in Git depend on your filesystem to have an
 302 efficient `lstat(2)` implementation, so that `st_mtime`
 303 information for working tree files can be cheaply checked to see
 304 if the file contents have changed from the version recorded in
 305 the index file.  Unfortunately, some filesystems have
 306 inefficient `lstat(2)`.  If your filesystem is one of them, you
 307 can set "assume unchanged" bit to paths you have not changed to
 308 cause Git not to do this check.  Note that setting this bit on a
 309 path does not mean Git will check the contents of the file to
 310 see if it has changed -- it makes Git to omit any checking and
 311 assume it has *not* changed.  When you make changes to working
 312 tree files, you have to explicitly tell Git about it by dropping
 313 "assume unchanged" bit, either before or after you modify them.
 314
 315 In order to set "assume unchanged" bit, use `--assume-unchanged`
 316 option.  To unset, use `--no-assume-unchanged`. To see which files
 317 have the "assume unchanged" bit set, use `git ls-files -v`
 318 (see linkgit:git-ls-files[1]).
 319
 320 The command looks at `core.ignorestat` configuration variable.  When
 321 this is true, paths updated with `git update-index paths...` and
 322 paths updated with other Git commands that update both index and
 323 working tree (e.g. 'git apply --index', 'git checkout-index -u',
 324 and 'git read-tree -u') are automatically marked as "assume
 325 unchanged".  Note that "assume unchanged" bit is *not* set if
 326 `git update-index --refresh` finds the working tree file matches
 327 the index (use `git update-index --really-refresh` if you want
 328 to mark them as "assume unchanged").
 329
 330
 331 Examples
 332 --------
 333 To update and refresh only the files already checked out:
 334
 335 ----------------
 336 $ git checkout-index -n -f -a && git update-index --ignore-missing --refresh
 337 ----------------
 338
 339 On an inefficient filesystem with `core.ignorestat` set::
 340 +
 341 ------------
 342 $ git update-index --really-refresh              <1>
 343 $ git update-index --no-assume-unchanged foo.c   <2>
 344 $ git diff --name-only                           <3>
 345 $ edit foo.c
 346 $ git diff --name-only                           <4>
 347 M foo.c
 348 $ git update-index foo.c                         <5>
 349 $ git diff --name-only                           <6>
 350 $ edit foo.c
 351 $ git diff --name-only                           <7>
 352 $ git update-index --no-assume-unchanged foo.c   <8>
 353 $ git diff --name-only                           <9>
 354 M foo.c
 355 ------------
 356 +
 357 <1> forces lstat(2) to set "assume unchanged" bits for paths that match index.
 358 <2> mark the path to be edited.
 359 <3> this does lstat(2) and finds index matches the path.
 360 <4> this does lstat(2) and finds index does *not* match the path.
 361 <5> registering the new version to index sets "assume unchanged" bit.
 362 <6> and it is assumed unchanged.
 363 <7> even after you edit it.
 364 <8> you can tell about the change after the fact.
 365 <9> now it checks with lstat(2) and finds it has been changed.
 366
 367
 368 Skip-worktree bit
 369 -----------------
 370
 371 Skip-worktree bit can be defined in one (long) sentence: When reading
 372 an entry, if it is marked as skip-worktree, then Git pretends its
 373 working directory version is up to date and read the index version
 374 instead.
 375
 376 To elaborate, "reading" means checking for file existence, reading
 377 file attributes or file content. The working directory version may be
 378 present or absent. If present, its content may match against the index
 379 version or not. Writing is not affected by this bit, content safety
 380 is still first priority. Note that Git _can_ update working directory
 381 file, that is marked skip-worktree, if it is safe to do so (i.e.
 382 working directory version matches index version)
 383
 384 Although this bit looks similar to assume-unchanged bit, its goal is
 385 different from assume-unchanged bit's. Skip-worktree also takes
 386 precedence over assume-unchanged bit when both are set.
 387
 388
 389 Configuration
 390 -------------
 391
 392 The command honors `core.filemode` configuration variable.  If
 393 your repository is on a filesystem whose executable bits are
 394 unreliable, this should be set to 'false' (see linkgit:git-config[1]).
 395 This causes the command to ignore differences in file modes recorded
 396 in the index and the file mode on the filesystem if they differ only on
 397 executable bit.   On such an unfortunate filesystem, you may
 398 need to use 'git update-index --chmod='.
 399
 400 Quite similarly, if `core.symlinks` configuration variable is set
 401 to 'false' (see linkgit:git-config[1]), symbolic links are checked out
 402 as plain files, and this command does not modify a recorded file mode
 403 from symbolic link to regular file.
 404
 405 The command looks at `core.ignorestat` configuration variable.  See
 406 'Using "assume unchanged" bit' section above.
 407
 408 The command also looks at `core.trustctime` configuration variable.
 409 It can be useful when the inode change time is regularly modified by
 410 something outside Git (file system crawlers and backup systems use
 411 ctime for marking files processed) (see linkgit:git-config[1]).
 412
 413
 414 SEE ALSO
 415 --------
 416 linkgit:git-config[1],
 417 linkgit:git-add[1],
 418 linkgit:git-ls-files[1]
 419
 420 GIT
 421 ---
 422 Part of the linkgit:git[1] suite