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              [--assume-unchanged | --no-assume-unchanged]
  18              [--skip-worktree | --no-skip-worktree]
  19              [--ignore-submodules]
  20              [--really-refresh] [--unresolve] [--again | -g]
  21              [--info-only] [--index-info]
  22              [-z] [--stdin]
  23              [--verbose]
  24              [--] [<file>]*
  25
  26 DESCRIPTION
  27 -----------
  28 Modifies the index or directory cache. Each file mentioned is updated
  29 into the index and any 'unmerged' or 'needs updating' state is
  30 cleared.
  31
  32 See also linkgit:git-add[1] for a more user-friendly way to do some of
  33 the most common operations on the index.
  34
  35 The way 'git update-index' handles files it is told about can be modified
  36 using the various options:
  37
  38 OPTIONS
  39 -------
  40 --add::
  41         If a specified file isn't in the index already then it's
  42         added.
  43         Default behaviour is to ignore new files.
  44
  45 --remove::
  46         If a specified file is in the index but is missing then it's
  47         removed.
  48         Default behavior is to ignore removed file.
  49
  50 --refresh::
  51         Looks at the current index and checks to see if merges or
  52         updates are needed by checking stat() information.
  53
  54 -q::
  55         Quiet.  If --refresh finds that the index needs an update, the
  56         default behavior is to error out.  This option makes
  57         'git update-index' continue anyway.
  58
  59 --ignore-submodules::
  60         Do not try to update submodules.  This option is only respected
  61         when passed before --refresh.
  62
  63 --unmerged::
  64         If --refresh finds unmerged changes in the index, the default
  65         behavior is to error out.  This option makes 'git update-index'
  66         continue anyway.
  67
  68 --ignore-missing::
  69         Ignores missing files during a --refresh
  70
  71 --cacheinfo <mode> <object> <path>::
  72         Directly insert the specified info into the index.
  73
  74 --index-info::
  75         Read index information from stdin.
  76
  77 --chmod=(+|-)x::
  78         Set the execute permissions on the updated files.
  79
  80 --assume-unchanged::
  81 --no-assume-unchanged::
  82         When these flags are specified, the object names recorded
  83         for the paths are not updated.  Instead, these options
  84         set and unset the "assume unchanged" bit for the
  85         paths.  When the "assume unchanged" bit is on, git stops
  86         checking the working tree files for possible
  87         modifications, so you need to manually unset the bit to
  88         tell git when you change the working tree file. This is
  89         sometimes helpful when working with a big project on a
  90         filesystem that has very slow lstat(2) system call
  91         (e.g. cifs).
  92 +
  93 This option can be also used as a coarse file-level mechanism
  94 to ignore uncommitted changes in tracked files (akin to what
  95 `.gitignore` does for untracked files).
  96 Git will fail (gracefully) in case it needs to modify this file
  97 in the index e.g. when merging in a commit;
  98 thus, in case the assumed-untracked file is changed upstream,
  99 you will need to handle the situation manually.
 100
 101 --really-refresh::
 102         Like '--refresh', but checks stat information unconditionally,
 103         without regard to the "assume unchanged" setting.
 104
 105 --skip-worktree::
 106 --no-skip-worktree::
 107         When one of these flags is specified, the object name recorded
 108         for the paths are not updated. Instead, these options
 109         set and unset the "skip-worktree" bit for the paths. See
 110         section "Skip-worktree bit" below for more information.
 111
 112 -g::
 113 --again::
 114         Runs 'git update-index' itself on the paths whose index
 115         entries are different from those from the `HEAD` commit.
 116
 117 --unresolve::
 118         Restores the 'unmerged' or 'needs updating' state of a
 119         file during a merge if it was cleared by accident.
 120
 121 --info-only::
 122         Do not create objects in the object database for all
 123         <file> arguments that follow this flag; just insert
 124         their object IDs into the index.
 125
 126 --force-remove::
 127         Remove the file from the index even when the working directory
 128         still has such a file. (Implies --remove.)
 129
 130 --replace::
 131         By default, when a file `path` exists in the index,
 132         'git update-index' refuses an attempt to add `path/file`.
 133         Similarly if a file `path/file` exists, a file `path`
 134         cannot be added.  With --replace flag, existing entries
 135         that conflict with the entry being added are
 136         automatically removed with warning messages.
 137
 138 --stdin::
 139         Instead of taking list of paths from the command line,
 140         read list of paths from the standard input.  Paths are
 141         separated by LF (i.e. one path per line) by default.
 142
 143 --verbose::
 144         Report what is being added and removed from index.
 145
 146 -z::
 147         Only meaningful with `--stdin`; paths are separated with
 148         NUL character instead of LF.
 149
 150 \--::
 151         Do not interpret any more arguments as options.
 152
 153 <file>::
 154         Files to act on.
 155         Note that files beginning with '.' are discarded. This includes
 156         `./file` and `dir/./file`. If you don't want this, then use
 157         cleaner names.
 158         The same applies to directories ending '/' and paths with '//'
 159
 160 Using --refresh
 161 ---------------
 162 '--refresh' does not calculate a new sha1 file or bring the index
 163 up-to-date for mode/content changes. But what it *does* do is to
 164 "re-match" the stat information of a file with the index, so that you
 165 can refresh the index for a file that hasn't been changed but where
 166 the stat entry is out of date.
 167
 168 For example, you'd want to do this after doing a 'git read-tree', to link
 169 up the stat index details with the proper files.
 170
 171 Using --cacheinfo or --info-only
 172 --------------------------------
 173 '--cacheinfo' is used to register a file that is not in the
 174 current working directory.  This is useful for minimum-checkout
 175 merging.
 176
 177 To pretend you have a file with mode and sha1 at path, say:
 178
 179 ----------------
 180 $ git update-index --cacheinfo mode sha1 path
 181 ----------------
 182
 183 '--info-only' is used to register files without placing them in the object
 184 database.  This is useful for status-only repositories.
 185
 186 Both '--cacheinfo' and '--info-only' behave similarly: the index is updated
 187 but the object database isn't.  '--cacheinfo' is useful when the object is
 188 in the database but the file isn't available locally.  '--info-only' is
 189 useful when the file is available, but you do not wish to update the
 190 object database.
 191
 192
 193 Using --index-info
 194 ------------------
 195
 196 `--index-info` is a more powerful mechanism that lets you feed
 197 multiple entry definitions from the standard input, and designed
 198 specifically for scripts.  It can take inputs of three formats:
 199
 200     . mode         SP sha1          TAB path
 201 +
 202 The first format is what "git-apply --index-info"
 203 reports, and used to reconstruct a partial tree
 204 that is used for phony merge base tree when falling
 205 back on 3-way merge.
 206
 207     . mode SP type SP sha1          TAB path
 208 +
 209 The second format is to stuff 'git ls-tree' output
 210 into the index file.
 211
 212     . mode         SP sha1 SP stage TAB path
 213 +
 214 This format is to put higher order stages into the
 215 index file and matches 'git ls-files --stage' output.
 216
 217 To place a higher stage entry to the index, the path should
 218 first be removed by feeding a mode=0 entry for the path, and
 219 then feeding necessary input lines in the third format.
 220
 221 For example, starting with this index:
 222
 223 ------------
 224 $ git ls-files -s
 225 100644 8a1218a1024a212bb3db30becd860315f9f3ac52 0       frotz
 226 ------------
 227
 228 you can feed the following input to `--index-info`:
 229
 230 ------------
 231 $ git update-index --index-info
 232 0 0000000000000000000000000000000000000000      frotz
 233 100644 8a1218a1024a212bb3db30becd860315f9f3ac52 1       frotz
 234 100755 8a1218a1024a212bb3db30becd860315f9f3ac52 2       frotz
 235 ------------
 236
 237 The first line of the input feeds 0 as the mode to remove the
 238 path; the SHA1 does not matter as long as it is well formatted.
 239 Then the second and third line feeds stage 1 and stage 2 entries
 240 for that path.  After the above, we would end up with this:
 241
 242 ------------
 243 $ git ls-files -s
 244 100644 8a1218a1024a212bb3db30becd860315f9f3ac52 1       frotz
 245 100755 8a1218a1024a212bb3db30becd860315f9f3ac52 2       frotz
 246 ------------
 247
 248
 249 Using ``assume unchanged'' bit
 250 ------------------------------
 251
 252 Many operations in git depend on your filesystem to have an
 253 efficient `lstat(2)` implementation, so that `st_mtime`
 254 information for working tree files can be cheaply checked to see
 255 if the file contents have changed from the version recorded in
 256 the index file.  Unfortunately, some filesystems have
 257 inefficient `lstat(2)`.  If your filesystem is one of them, you
 258 can set "assume unchanged" bit to paths you have not changed to
 259 cause git not to do this check.  Note that setting this bit on a
 260 path does not mean git will check the contents of the file to
 261 see if it has changed -- it makes git to omit any checking and
 262 assume it has *not* changed.  When you make changes to working
 263 tree files, you have to explicitly tell git about it by dropping
 264 "assume unchanged" bit, either before or after you modify them.
 265
 266 In order to set "assume unchanged" bit, use `--assume-unchanged`
 267 option.  To unset, use `--no-assume-unchanged`.
 268
 269 The command looks at `core.ignorestat` configuration variable.  When
 270 this is true, paths updated with `git update-index paths...` and
 271 paths updated with other git commands that update both index and
 272 working tree (e.g. 'git apply --index', 'git checkout-index -u',
 273 and 'git read-tree -u') are automatically marked as "assume
 274 unchanged".  Note that "assume unchanged" bit is *not* set if
 275 `git update-index --refresh` finds the working tree file matches
 276 the index (use `git update-index --really-refresh` if you want
 277 to mark them as "assume unchanged").
 278
 279
 280 Examples
 281 --------
 282 To update and refresh only the files already checked out:
 283
 284 ----------------
 285 $ git checkout-index -n -f -a && git update-index --ignore-missing --refresh
 286 ----------------
 287
 288 On an inefficient filesystem with `core.ignorestat` set::
 289 +
 290 ------------
 291 $ git update-index --really-refresh              <1>
 292 $ git update-index --no-assume-unchanged foo.c   <2>
 293 $ git diff --name-only                           <3>
 294 $ edit foo.c
 295 $ git diff --name-only                           <4>
 296 M foo.c
 297 $ git update-index foo.c                         <5>
 298 $ git diff --name-only                           <6>
 299 $ edit foo.c
 300 $ git diff --name-only                           <7>
 301 $ git update-index --no-assume-unchanged foo.c   <8>
 302 $ git diff --name-only                           <9>
 303 M foo.c
 304 ------------
 305 +
 306 <1> forces lstat(2) to set "assume unchanged" bits for paths that match index.
 307 <2> mark the path to be edited.
 308 <3> this does lstat(2) and finds index matches the path.
 309 <4> this does lstat(2) and finds index does *not* match the path.
 310 <5> registering the new version to index sets "assume unchanged" bit.
 311 <6> and it is assumed unchanged.
 312 <7> even after you edit it.
 313 <8> you can tell about the change after the fact.
 314 <9> now it checks with lstat(2) and finds it has been changed.
 315
 316
 317 Skip-worktree bit
 318 -----------------
 319
 320 Skip-worktree bit can be defined in one (long) sentence: When reading
 321 an entry, if it is marked as skip-worktree, then Git pretends its
 322 working directory version is up to date and read the index version
 323 instead.
 324
 325 To elaborate, "reading" means checking for file existence, reading
 326 file attributes or file content. The working directory version may be
 327 present or absent. If present, its content may match against the index
 328 version or not. Writing is not affected by this bit, content safety
 329 is still first priority. Note that Git _can_ update working directory
 330 file, that is marked skip-worktree, if it is safe to do so (i.e.
 331 working directory version matches index version)
 332
 333 Although this bit looks similar to assume-unchanged bit, its goal is
 334 different from assume-unchanged bit's. Skip-worktree also takes
 335 precedence over assume-unchanged bit when both are set.
 336
 337
 338 Configuration
 339 -------------
 340
 341 The command honors `core.filemode` configuration variable.  If
 342 your repository is on a filesystem whose executable bits are
 343 unreliable, this should be set to 'false' (see linkgit:git-config[1]).
 344 This causes the command to ignore differences in file modes recorded
 345 in the index and the file mode on the filesystem if they differ only on
 346 executable bit.   On such an unfortunate filesystem, you may
 347 need to use 'git update-index --chmod='.
 348
 349 Quite similarly, if `core.symlinks` configuration variable is set
 350 to 'false' (see linkgit:git-config[1]), symbolic links are checked out
 351 as plain files, and this command does not modify a recorded file mode
 352 from symbolic link to regular file.
 353
 354 The command looks at `core.ignorestat` configuration variable.  See
 355 'Using "assume unchanged" bit' section above.
 356
 357 The command also looks at `core.trustctime` configuration variable.
 358 It can be useful when the inode change time is regularly modified by
 359 something outside Git (file system crawlers and backup systems use
 360 ctime for marking files processed) (see linkgit:git-config[1]).
 361
 362
 363 SEE ALSO
 364 --------
 365 linkgit:git-config[1],
 366 linkgit:git-add[1]
 367
 368
 369 Author
 370 ------
 371 Written by Linus Torvalds <torvalds@osdl.org>
 372
 373 Documentation
 374 --------------
 375 Documentation by David Greaves, Junio C Hamano and the git-list <git@vger.kernel.org>.
 376
 377 GIT
 378 ---
 379 Part of the linkgit:git[1] suite