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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 [--[no-]ignore-skip-worktree-entries]
20 [--[no-]fsmonitor-valid]
21 [--ignore-submodules]
22 [--[no-]split-index]
23 [--[no-|test-|force-]untracked-cache]
24 [--[no-]fsmonitor]
25 [--really-refresh] [--unresolve] [--again | -g]
26 [--info-only] [--index-info]
27 [-z] [--stdin] [--index-version <n>]
28 [--verbose]
29 [--] [<file>...]
30
31 DESCRIPTION
32 -----------
33 Modifies the index or directory cache. Each file mentioned is updated
34 into the index and any 'unmerged' or 'needs updating' state is
35 cleared.
36
37 See also linkgit:git-add[1] for a more user-friendly way to do some of
38 the most common operations on the index.
39
40 The way 'git update-index' handles files it is told about can be modified
41 using the various options:
42
43 OPTIONS
44 -------
45 --add::
46 If a specified file isn't in the index already then it's
47 added.
48 Default behaviour is to ignore new files.
49
50 --remove::
51 If a specified file is in the index but is missing then it's
52 removed.
53 Default behavior is to ignore removed file.
54
55 --refresh::
56 Looks at the current index and checks to see if merges or
57 updates are needed by checking stat() information.
58
59 -q::
60 Quiet. If --refresh finds that the index needs an update, the
61 default behavior is to error out. This option makes
62 'git update-index' continue anyway.
63
64 --ignore-submodules::
65 Do not try to update submodules. This option is only respected
66 when passed before --refresh.
67
68 --unmerged::
69 If --refresh finds unmerged changes in the index, the default
70 behavior is to error out. This option makes 'git update-index'
71 continue anyway.
72
73 --ignore-missing::
74 Ignores missing files during a --refresh
75
76 --cacheinfo <mode>,<object>,<path>::
77 --cacheinfo <mode> <object> <path>::
78 Directly insert the specified info into the index. For
79 backward compatibility, you can also give these three
80 arguments as three separate parameters, but new users are
81 encouraged to use a single-parameter form.
82
83 --index-info::
84 Read index information from stdin.
85
86 --chmod=(+|-)x::
87 Set the execute permissions on the updated files.
88
89 --[no-]assume-unchanged::
90 When this flag is specified, the object names recorded
91 for the paths are not updated. Instead, this option
92 sets/unsets the "assume unchanged" bit for the
93 paths. When the "assume unchanged" bit is on, the user
94 promises not to change the file and allows Git to assume
95 that the working tree file matches what is recorded in
96 the index. If you want to change the working tree file,
97 you need to unset the bit to tell Git. This is
98 sometimes helpful when working with a big project on a
99 filesystem that has very slow lstat(2) system call
100 (e.g. cifs).
101 +
102 Git will fail (gracefully) in case it needs to modify this file
103 in the index e.g. when merging in a commit;
104 thus, in case the assumed-untracked file is changed upstream,
105 you will need to handle the situation manually.
106
107 --really-refresh::
108 Like `--refresh`, but checks stat information unconditionally,
109 without regard to the "assume unchanged" setting.
110
111 --[no-]skip-worktree::
112 When one of these flags is specified, the object name recorded
113 for the paths are not updated. Instead, these options
114 set and unset the "skip-worktree" bit for the paths. See
115 section "Skip-worktree bit" below for more information.
116
117
118 --[no-]ignore-skip-worktree-entries::
119 Do not remove skip-worktree (AKA "index-only") entries even when
120 the `--remove` option was specified.
121
122 --[no-]fsmonitor-valid::
123 When one of these flags is specified, the object name recorded
124 for the paths are not updated. Instead, these options
125 set and unset the "fsmonitor valid" bit for the paths. See
126 section "File System Monitor" below for more information.
127
128 -g::
129 --again::
130 Runs 'git update-index' itself on the paths whose index
131 entries are different from those from the `HEAD` commit.
132
133 --unresolve::
134 Restores the 'unmerged' or 'needs updating' state of a
135 file during a merge if it was cleared by accident.
136
137 --info-only::
138 Do not create objects in the object database for all
139 <file> arguments that follow this flag; just insert
140 their object IDs into the index.
141
142 --force-remove::
143 Remove the file from the index even when the working directory
144 still has such a file. (Implies --remove.)
145
146 --replace::
147 By default, when a file `path` exists in the index,
148 'git update-index' refuses an attempt to add `path/file`.
149 Similarly if a file `path/file` exists, a file `path`
150 cannot be added. With --replace flag, existing entries
151 that conflict with the entry being added are
152 automatically removed with warning messages.
153
154 --stdin::
155 Instead of taking list of paths from the command line,
156 read list of paths from the standard input. Paths are
157 separated by LF (i.e. one path per line) by default.
158
159 --verbose::
160 Report what is being added and removed from index.
161
162 --index-version <n>::
163 Write the resulting index out in the named on-disk format version.
164 Supported versions are 2, 3 and 4. The current default version is 2
165 or 3, depending on whether extra features are used, such as
166 `git add -N`.
167 +
168 Version 4 performs a simple pathname compression that reduces index
169 size by 30%-50% on large repositories, which results in faster load
170 time. Version 4 is relatively young (first released in 1.8.0 in
171 October 2012). Other Git implementations such as JGit and libgit2
172 may not support it yet.
173
174 -z::
175 Only meaningful with `--stdin` or `--index-info`; paths are
176 separated with NUL character instead of LF.
177
178 --split-index::
179 --no-split-index::
180 Enable or disable split index mode. If split-index mode is
181 already enabled and `--split-index` is given again, all
182 changes in $GIT_DIR/index are pushed back to the shared index
183 file.
184 +
185 These options take effect whatever the value of the `core.splitIndex`
186 configuration variable (see linkgit:git-config[1]). But a warning is
187 emitted when the change goes against the configured value, as the
188 configured value will take effect next time the index is read and this
189 will remove the intended effect of the option.
190
191 --untracked-cache::
192 --no-untracked-cache::
193 Enable or disable untracked cache feature. Please use
194 `--test-untracked-cache` before enabling it.
195 +
196 These options take effect whatever the value of the `core.untrackedCache`
197 configuration variable (see linkgit:git-config[1]). But a warning is
198 emitted when the change goes against the configured value, as the
199 configured value will take effect next time the index is read and this
200 will remove the intended effect of the option.
201
202 --test-untracked-cache::
203 Only perform tests on the working directory to make sure
204 untracked cache can be used. You have to manually enable
205 untracked cache using `--untracked-cache` or
206 `--force-untracked-cache` or the `core.untrackedCache`
207 configuration variable afterwards if you really want to use
208 it. If a test fails the exit code is 1 and a message
209 explains what is not working as needed, otherwise the exit
210 code is 0 and OK is printed.
211
212 --force-untracked-cache::
213 Same as `--untracked-cache`. Provided for backwards
214 compatibility with older versions of Git where
215 `--untracked-cache` used to imply `--test-untracked-cache` but
216 this option would enable the extension unconditionally.
217
218 --fsmonitor::
219 --no-fsmonitor::
220 Enable or disable files system monitor feature. These options
221 take effect whatever the value of the `core.fsmonitor`
222 configuration variable (see linkgit:git-config[1]). But a warning
223 is emitted when the change goes against the configured value, as
224 the configured value will take effect next time the index is
225 read and this will remove the intended effect of the option.
226
227 \--::
228 Do not interpret any more arguments as options.
229
230 <file>::
231 Files to act on.
232 Note that files beginning with '.' are discarded. This includes
233 `./file` and `dir/./file`. If you don't want this, then use
234 cleaner names.
235 The same applies to directories ending '/' and paths with '//'
236
237 USING --REFRESH
238 ---------------
239 `--refresh` does not calculate a new sha1 file or bring the index
240 up to date for mode/content changes. But what it *does* do is to
241 "re-match" the stat information of a file with the index, so that you
242 can refresh the index for a file that hasn't been changed but where
243 the stat entry is out of date.
244
245 For example, you'd want to do this after doing a 'git read-tree', to link
246 up the stat index details with the proper files.
247
248 USING --CACHEINFO OR --INFO-ONLY
249 --------------------------------
250 `--cacheinfo` is used to register a file that is not in the
251 current working directory. This is useful for minimum-checkout
252 merging.
253
254 To pretend you have a file at path with mode and sha1, say:
255
256 ----------------
257 $ git update-index --add --cacheinfo <mode>,<sha1>,<path>
258 ----------------
259
260 `--info-only` is used to register files without placing them in the object
261 database. This is useful for status-only repositories.
262
263 Both `--cacheinfo` and `--info-only` behave similarly: the index is updated
264 but the object database isn't. `--cacheinfo` is useful when the object is
265 in the database but the file isn't available locally. `--info-only` is
266 useful when the file is available, but you do not wish to update the
267 object database.
268
269
270 USING --INDEX-INFO
271 ------------------
272
273 `--index-info` is a more powerful mechanism that lets you feed
274 multiple entry definitions from the standard input, and designed
275 specifically for scripts. It can take inputs of three formats:
276
277 . mode SP type SP sha1 TAB path
278 +
279 This format is to stuff `git ls-tree` output into the index.
280
281 . mode SP sha1 SP stage TAB path
282 +
283 This format is to put higher order stages into the
284 index file and matches 'git ls-files --stage' output.
285
286 . mode SP sha1 TAB path
287 +
288 This format is no longer produced by any Git command, but is
289 and will continue to be supported by `update-index --index-info`.
290
291 To place a higher stage entry to the index, the path should
292 first be removed by feeding a mode=0 entry for the path, and
293 then feeding necessary input lines in the third format.
294
295 For example, starting with this index:
296
297 ------------
298 $ git ls-files -s
299 100644 8a1218a1024a212bb3db30becd860315f9f3ac52 0 frotz
300 ------------
301
302 you can feed the following input to `--index-info`:
303
304 ------------
305 $ git update-index --index-info
306 0 0000000000000000000000000000000000000000 frotz
307 100644 8a1218a1024a212bb3db30becd860315f9f3ac52 1 frotz
308 100755 8a1218a1024a212bb3db30becd860315f9f3ac52 2 frotz
309 ------------
310
311 The first line of the input feeds 0 as the mode to remove the
312 path; the SHA-1 does not matter as long as it is well formatted.
313 Then the second and third line feeds stage 1 and stage 2 entries
314 for that path. After the above, we would end up with this:
315
316 ------------
317 $ git ls-files -s
318 100644 8a1218a1024a212bb3db30becd860315f9f3ac52 1 frotz
319 100755 8a1218a1024a212bb3db30becd860315f9f3ac52 2 frotz
320 ------------
321
322
323 USING ``ASSUME UNCHANGED'' BIT
324 ------------------------------
325
326 Many operations in Git depend on your filesystem to have an
327 efficient `lstat(2)` implementation, so that `st_mtime`
328 information for working tree files can be cheaply checked to see
329 if the file contents have changed from the version recorded in
330 the index file. Unfortunately, some filesystems have
331 inefficient `lstat(2)`. If your filesystem is one of them, you
332 can set "assume unchanged" bit to paths you have not changed to
333 cause Git not to do this check. Note that setting this bit on a
334 path does not mean Git will check the contents of the file to
335 see if it has changed -- it makes Git to omit any checking and
336 assume it has *not* changed. When you make changes to working
337 tree files, you have to explicitly tell Git about it by dropping
338 "assume unchanged" bit, either before or after you modify them.
339
340 In order to set "assume unchanged" bit, use `--assume-unchanged`
341 option. To unset, use `--no-assume-unchanged`. To see which files
342 have the "assume unchanged" bit set, use `git ls-files -v`
343 (see linkgit:git-ls-files[1]).
344
345 The command looks at `core.ignorestat` configuration variable. When
346 this is true, paths updated with `git update-index paths...` and
347 paths updated with other Git commands that update both index and
348 working tree (e.g. 'git apply --index', 'git checkout-index -u',
349 and 'git read-tree -u') are automatically marked as "assume
350 unchanged". Note that "assume unchanged" bit is *not* set if
351 `git update-index --refresh` finds the working tree file matches
352 the index (use `git update-index --really-refresh` if you want
353 to mark them as "assume unchanged").
354
355
356 EXAMPLES
357 --------
358 To update and refresh only the files already checked out:
359
360 ----------------
361 $ git checkout-index -n -f -a && git update-index --ignore-missing --refresh
362 ----------------
363
364 On an inefficient filesystem with `core.ignorestat` set::
365 +
366 ------------
367 $ git update-index --really-refresh <1>
368 $ git update-index --no-assume-unchanged foo.c <2>
369 $ git diff --name-only <3>
370 $ edit foo.c
371 $ git diff --name-only <4>
372 M foo.c
373 $ git update-index foo.c <5>
374 $ git diff --name-only <6>
375 $ edit foo.c
376 $ git diff --name-only <7>
377 $ git update-index --no-assume-unchanged foo.c <8>
378 $ git diff --name-only <9>
379 M foo.c
380 ------------
381 +
382 <1> forces lstat(2) to set "assume unchanged" bits for paths that match index.
383 <2> mark the path to be edited.
384 <3> this does lstat(2) and finds index matches the path.
385 <4> this does lstat(2) and finds index does *not* match the path.
386 <5> registering the new version to index sets "assume unchanged" bit.
387 <6> and it is assumed unchanged.
388 <7> even after you edit it.
389 <8> you can tell about the change after the fact.
390 <9> now it checks with lstat(2) and finds it has been changed.
391
392
393 SKIP-WORKTREE BIT
394 -----------------
395
396 Skip-worktree bit can be defined in one (long) sentence: When reading
397 an entry, if it is marked as skip-worktree, then Git pretends its
398 working directory version is up to date and read the index version
399 instead.
400
401 To elaborate, "reading" means checking for file existence, reading
402 file attributes or file content. The working directory version may be
403 present or absent. If present, its content may match against the index
404 version or not. Writing is not affected by this bit, content safety
405 is still first priority. Note that Git _can_ update working directory
406 file, that is marked skip-worktree, if it is safe to do so (i.e.
407 working directory version matches index version)
408
409 Although this bit looks similar to assume-unchanged bit, its goal is
410 different from assume-unchanged bit's. Skip-worktree also takes
411 precedence over assume-unchanged bit when both are set.
412
413 SPLIT INDEX
414 -----------
415
416 This mode is designed for repositories with very large indexes, and
417 aims at reducing the time it takes to repeatedly write these indexes.
418
419 In this mode, the index is split into two files, $GIT_DIR/index and
420 $GIT_DIR/sharedindex.<SHA-1>. Changes are accumulated in
421 $GIT_DIR/index, the split index, while the shared index file contains
422 all index entries and stays unchanged.
423
424 All changes in the split index are pushed back to the shared index
425 file when the number of entries in the split index reaches a level
426 specified by the splitIndex.maxPercentChange config variable (see
427 linkgit:git-config[1]).
428
429 Each time a new shared index file is created, the old shared index
430 files are deleted if their modification time is older than what is
431 specified by the splitIndex.sharedIndexExpire config variable (see
432 linkgit:git-config[1]).
433
434 To avoid deleting a shared index file that is still used, its
435 modification time is updated to the current time everytime a new split
436 index based on the shared index file is either created or read from.
437
438 UNTRACKED CACHE
439 ---------------
440
441 This cache is meant to speed up commands that involve determining
442 untracked files such as `git status`.
443
444 This feature works by recording the mtime of the working tree
445 directories and then omitting reading directories and stat calls
446 against files in those directories whose mtime hasn't changed. For
447 this to work the underlying operating system and file system must
448 change the `st_mtime` field of directories if files in the directory
449 are added, modified or deleted.
450
451 You can test whether the filesystem supports that with the
452 `--test-untracked-cache` option. The `--untracked-cache` option used
453 to implicitly perform that test in older versions of Git, but that's
454 no longer the case.
455
456 If you want to enable (or disable) this feature, it is easier to use
457 the `core.untrackedCache` configuration variable (see
458 linkgit:git-config[1]) than using the `--untracked-cache` option to
459 `git update-index` in each repository, especially if you want to do so
460 across all repositories you use, because you can set the configuration
461 variable to `true` (or `false`) in your `$HOME/.gitconfig` just once
462 and have it affect all repositories you touch.
463
464 When the `core.untrackedCache` configuration variable is changed, the
465 untracked cache is added to or removed from the index the next time a
466 command reads the index; while when `--[no-|force-]untracked-cache`
467 are used, the untracked cache is immediately added to or removed from
468 the index.
469
470 Before 2.17, the untracked cache had a bug where replacing a directory
471 with a symlink to another directory could cause it to incorrectly show
472 files tracked by git as untracked. See the "status: add a failing test
473 showing a core.untrackedCache bug" commit to git.git. A workaround for
474 that is (and this might work for other undiscovered bugs in the
475 future):
476
477 ----------------
478 $ git -c core.untrackedCache=false status
479 ----------------
480
481 This bug has also been shown to affect non-symlink cases of replacing
482 a directory with a file when it comes to the internal structures of
483 the untracked cache, but no case has been reported where this resulted in
484 wrong "git status" output.
485
486 There are also cases where existing indexes written by git versions
487 before 2.17 will reference directories that don't exist anymore,
488 potentially causing many "could not open directory" warnings to be
489 printed on "git status". These are new warnings for existing issues
490 that were previously silently discarded.
491
492 As with the bug described above the solution is to one-off do a "git
493 status" run with `core.untrackedCache=false` to flush out the leftover
494 bad data.
495
496 FILE SYSTEM MONITOR
497 -------------------
498
499 This feature is intended to speed up git operations for repos that have
500 large working directories.
501
502 It enables git to work together with a file system monitor (see the
503 "fsmonitor-watchman" section of linkgit:githooks[5]) that can
504 inform it as to what files have been modified. This enables git to avoid
505 having to lstat() every file to find modified files.
506
507 When used in conjunction with the untracked cache, it can further improve
508 performance by avoiding the cost of scanning the entire working directory
509 looking for new files.
510
511 If you want to enable (or disable) this feature, it is easier to use
512 the `core.fsmonitor` configuration variable (see
513 linkgit:git-config[1]) than using the `--fsmonitor` option to
514 `git update-index` in each repository, especially if you want to do so
515 across all repositories you use, because you can set the configuration
516 variable in your `$HOME/.gitconfig` just once and have it affect all
517 repositories you touch.
518
519 When the `core.fsmonitor` configuration variable is changed, the
520 file system monitor is added to or removed from the index the next time
521 a command reads the index. When `--[no-]fsmonitor` are used, the file
522 system monitor is immediately added to or removed from the index.
523
524 CONFIGURATION
525 -------------
526
527 The command honors `core.filemode` configuration variable. If
528 your repository is on a filesystem whose executable bits are
529 unreliable, this should be set to 'false' (see linkgit:git-config[1]).
530 This causes the command to ignore differences in file modes recorded
531 in the index and the file mode on the filesystem if they differ only on
532 executable bit. On such an unfortunate filesystem, you may
533 need to use 'git update-index --chmod='.
534
535 Quite similarly, if `core.symlinks` configuration variable is set
536 to 'false' (see linkgit:git-config[1]), symbolic links are checked out
537 as plain files, and this command does not modify a recorded file mode
538 from symbolic link to regular file.
539
540 The command looks at `core.ignorestat` configuration variable. See
541 'Using "assume unchanged" bit' section above.
542
543 The command also looks at `core.trustctime` configuration variable.
544 It can be useful when the inode change time is regularly modified by
545 something outside Git (file system crawlers and backup systems use
546 ctime for marking files processed) (see linkgit:git-config[1]).
547
548 The untracked cache extension can be enabled by the
549 `core.untrackedCache` configuration variable (see
550 linkgit:git-config[1]).
551
552 SEE ALSO
553 --------
554 linkgit:git-config[1],
555 linkgit:git-add[1],
556 linkgit:git-ls-files[1]
557
558 GIT
559 ---
560 Part of the linkgit:git[1] suite