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