Merge branch 'nd/sparse'
[git/git.git] / 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 You should remember that an explicit 'git add' operation will
97 still cause the file to be refreshed from the working tree.
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 --skip-worktree::
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 -z::
149 Only meaningful with `--stdin`; paths are separated with
150 NUL character instead of LF.
151
152 \--::
153 Do not interpret any more arguments as options.
154
155 <file>::
156 Files to act on.
157 Note that files beginning with '.' are discarded. This includes
158 `./file` and `dir/./file`. If you don't want this, then use
159 cleaner names.
160 The same applies to directories ending '/' and paths with '//'
161
162 Using --refresh
163 ---------------
164 '--refresh' does not calculate a new sha1 file or bring the index
165 up-to-date for mode/content changes. But what it *does* do is to
166 "re-match" the stat information of a file with the index, so that you
167 can refresh the index for a file that hasn't been changed but where
168 the stat entry is out of date.
169
170 For example, you'd want to do this after doing a 'git-read-tree', to link
171 up the stat index details with the proper files.
172
173 Using --cacheinfo or --info-only
174 --------------------------------
175 '--cacheinfo' is used to register a file that is not in the
176 current working directory. This is useful for minimum-checkout
177 merging.
178
179 To pretend you have a file with mode and sha1 at path, say:
180
181 ----------------
182 $ git update-index --cacheinfo mode sha1 path
183 ----------------
184
185 '--info-only' is used to register files without placing them in the object
186 database. This is useful for status-only repositories.
187
188 Both '--cacheinfo' and '--info-only' behave similarly: the index is updated
189 but the object database isn't. '--cacheinfo' is useful when the object is
190 in the database but the file isn't available locally. '--info-only' is
191 useful when the file is available, but you do not wish to update the
192 object database.
193
194
195 Using --index-info
196 ------------------
197
198 `--index-info` is a more powerful mechanism that lets you feed
199 multiple entry definitions from the standard input, and designed
200 specifically for scripts. It can take inputs of three formats:
201
202 . mode SP sha1 TAB path
203 +
204 The first format is what "git-apply --index-info"
205 reports, and used to reconstruct a partial tree
206 that is used for phony merge base tree when falling
207 back on 3-way merge.
208
209 . mode SP type SP sha1 TAB path
210 +
211 The second format is to stuff 'git-ls-tree' output
212 into the index file.
213
214 . mode SP sha1 SP stage TAB path
215 +
216 This format is to put higher order stages into the
217 index file and matches 'git-ls-files --stage' output.
218
219 To place a higher stage entry to the index, the path should
220 first be removed by feeding a mode=0 entry for the path, and
221 then feeding necessary input lines in the third format.
222
223 For example, starting with this index:
224
225 ------------
226 $ git ls-files -s
227 100644 8a1218a1024a212bb3db30becd860315f9f3ac52 0 frotz
228 ------------
229
230 you can feed the following input to `--index-info`:
231
232 ------------
233 $ git update-index --index-info
234 0 0000000000000000000000000000000000000000 frotz
235 100644 8a1218a1024a212bb3db30becd860315f9f3ac52 1 frotz
236 100755 8a1218a1024a212bb3db30becd860315f9f3ac52 2 frotz
237 ------------
238
239 The first line of the input feeds 0 as the mode to remove the
240 path; the SHA1 does not matter as long as it is well formatted.
241 Then the second and third line feeds stage 1 and stage 2 entries
242 for that path. After the above, we would end up with this:
243
244 ------------
245 $ git ls-files -s
246 100644 8a1218a1024a212bb3db30becd860315f9f3ac52 1 frotz
247 100755 8a1218a1024a212bb3db30becd860315f9f3ac52 2 frotz
248 ------------
249
250
251 Using ``assume unchanged'' bit
252 ------------------------------
253
254 Many operations in git depend on your filesystem to have an
255 efficient `lstat(2)` implementation, so that `st_mtime`
256 information for working tree files can be cheaply checked to see
257 if the file contents have changed from the version recorded in
258 the index file. Unfortunately, some filesystems have
259 inefficient `lstat(2)`. If your filesystem is one of them, you
260 can set "assume unchanged" bit to paths you have not changed to
261 cause git not to do this check. Note that setting this bit on a
262 path does not mean git will check the contents of the file to
263 see if it has changed -- it makes git to omit any checking and
264 assume it has *not* changed. When you make changes to working
265 tree files, you have to explicitly tell git about it by dropping
266 "assume unchanged" bit, either before or after you modify them.
267
268 In order to set "assume unchanged" bit, use `--assume-unchanged`
269 option. To unset, use `--no-assume-unchanged`.
270
271 The command looks at `core.ignorestat` configuration variable. When
272 this is true, paths updated with `git update-index paths...` and
273 paths updated with other git commands that update both index and
274 working tree (e.g. 'git-apply --index', 'git-checkout-index -u',
275 and 'git-read-tree -u') are automatically marked as "assume
276 unchanged". Note that "assume unchanged" bit is *not* set if
277 `git update-index --refresh` finds the working tree file matches
278 the index (use `git update-index --really-refresh` if you want
279 to mark them as "assume unchanged").
280
281
282 Examples
283 --------
284 To update and refresh only the files already checked out:
285
286 ----------------
287 $ git checkout-index -n -f -a && git update-index --ignore-missing --refresh
288 ----------------
289
290 On an inefficient filesystem with `core.ignorestat` set::
291 +
292 ------------
293 $ git update-index --really-refresh <1>
294 $ git update-index --no-assume-unchanged foo.c <2>
295 $ git diff --name-only <3>
296 $ edit foo.c
297 $ git diff --name-only <4>
298 M foo.c
299 $ git update-index foo.c <5>
300 $ git diff --name-only <6>
301 $ edit foo.c
302 $ git diff --name-only <7>
303 $ git update-index --no-assume-unchanged foo.c <8>
304 $ git diff --name-only <9>
305 M foo.c
306 ------------
307 +
308 <1> forces lstat(2) to set "assume unchanged" bits for paths that match index.
309 <2> mark the path to be edited.
310 <3> this does lstat(2) and finds index matches the path.
311 <4> this does lstat(2) and finds index does *not* match the path.
312 <5> registering the new version to index sets "assume unchanged" bit.
313 <6> and it is assumed unchanged.
314 <7> even after you edit it.
315 <8> you can tell about the change after the fact.
316 <9> now it checks with lstat(2) and finds it has been changed.
317
318
319 Skip-worktree bit
320 -----------------
321
322 Skip-worktree bit can be defined in one (long) sentence: When reading
323 an entry, if it is marked as skip-worktree, then Git pretends its
324 working directory version is up to date and read the index version
325 instead.
326
327 To elaborate, "reading" means checking for file existence, reading
328 file attributes or file content. The working directory version may be
329 present or absent. If present, its content may match against the index
330 version or not. Writing is not affected by this bit, content safety
331 is still first priority. Note that Git _can_ update working directory
332 file, that is marked skip-worktree, if it is safe to do so (i.e.
333 working directory version matches index version)
334
335 Although this bit looks similar to assume-unchanged bit, its goal is
336 different from assume-unchanged bit's. Skip-worktree also takes
337 precedence over assume-unchanged bit when both are set.
338
339
340 Configuration
341 -------------
342
343 The command honors `core.filemode` configuration variable. If
344 your repository is on a filesystem whose executable bits are
345 unreliable, this should be set to 'false' (see linkgit:git-config[1]).
346 This causes the command to ignore differences in file modes recorded
347 in the index and the file mode on the filesystem if they differ only on
348 executable bit. On such an unfortunate filesystem, you may
349 need to use 'git-update-index --chmod='.
350
351 Quite similarly, if `core.symlinks` configuration variable is set
352 to 'false' (see linkgit:git-config[1]), symbolic links are checked out
353 as plain files, and this command does not modify a recorded file mode
354 from symbolic link to regular file.
355
356 The command looks at `core.ignorestat` configuration variable. See
357 'Using "assume unchanged" bit' section above.
358
359 The command also looks at `core.trustctime` configuration variable.
360 It can be useful when the inode change time is regularly modified by
361 something outside Git (file system crawlers and backup systems use
362 ctime for marking files processed) (see linkgit:git-config[1]).
363
364
365 SEE ALSO
366 --------
367 linkgit:git-config[1],
368 linkgit:git-add[1]
369
370
371 Author
372 ------
373 Written by Linus Torvalds <torvalds@osdl.org>
374
375 Documentation
376 --------------
377 Documentation by David Greaves, Junio C Hamano and the git-list <git@vger.kernel.org>.
378
379 GIT
380 ---
381 Part of the linkgit:git[1] suite