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1 '\" t
2 .\" Title: git-diff-index
3 .\" Author: [FIXME: author] [see http://www.docbook.org/tdg5/en/html/author]
4 .\" Generator: DocBook XSL Stylesheets vsnapshot <http://docbook.sf.net/>
5 .\" Date: 2023-08-04
6 .\" Manual: Git Manual
7 .\" Source: Git 2.42.0.rc0
8 .\" Language: English
9 .\"
10 .TH "GIT\-DIFF\-INDEX" "1" "2023\-08\-04" "Git 2\&.42\&.0\&.rc0" "Git Manual"
11 .\" -----------------------------------------------------------------
12 .\" * Define some portability stuff
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15 .\" http://bugs.debian.org/507673
16 .\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html
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24 .nh
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28 .\" * MAIN CONTENT STARTS HERE *
29 .\" -----------------------------------------------------------------
30 .SH "NAME"
31 git-diff-index \- Compare a tree to the working tree or index
32 .SH "SYNOPSIS"
33 .sp
34 .nf
35 \fIgit diff\-index\fR [\-m] [\-\-cached] [\-\-merge\-base] [<common\-diff\-options>] <tree\-ish> [<path>\&...]
36 .fi
37 .sp
38 .SH "DESCRIPTION"
39 .sp
40 Compares the content and mode of the blobs found in a tree object with the corresponding tracked files in the working tree, or with the corresponding paths in the index\&. When <path> arguments are present, compares only paths matching those patterns\&. Otherwise all tracked files are compared\&.
41 .SH "OPTIONS"
42 .PP
43 \-p, \-u, \-\-patch
44 .RS 4
45 Generate patch (see section titled "Generating patch text with \-p")\&.
46 .RE
47 .PP
48 \-s, \-\-no\-patch
49 .RS 4
50 Suppress all output from the diff machinery\&. Useful for commands like
51 \fBgit show\fR
52 that show the patch by default to squelch their output, or to cancel the effect of options like
53 \fB\-\-patch\fR,
54 \fB\-\-stat\fR
55 earlier on the command line in an alias\&.
56 .RE
57 .PP
58 \-U<n>, \-\-unified=<n>
59 .RS 4
60 Generate diffs with <n> lines of context instead of the usual three\&. Implies
61 \fB\-\-patch\fR\&.
62 .RE
63 .PP
64 \-\-output=<file>
65 .RS 4
66 Output to a specific file instead of stdout\&.
67 .RE
68 .PP
69 \-\-output\-indicator\-new=<char>, \-\-output\-indicator\-old=<char>, \-\-output\-indicator\-context=<char>
70 .RS 4
71 Specify the character used to indicate new, old or context lines in the generated patch\&. Normally they are
72 \fI+\fR,
73 \fI\-\fR
74 and \*(Aq \*(Aq respectively\&.
75 .RE
76 .PP
77 \-\-raw
78 .RS 4
79 Generate the diff in raw format\&. This is the default\&.
80 .RE
81 .PP
82 \-\-patch\-with\-raw
83 .RS 4
84 Synonym for
85 \fB\-p \-\-raw\fR\&.
86 .RE
87 .PP
88 \-\-indent\-heuristic
89 .RS 4
90 Enable the heuristic that shifts diff hunk boundaries to make patches easier to read\&. This is the default\&.
91 .RE
92 .PP
93 \-\-no\-indent\-heuristic
94 .RS 4
95 Disable the indent heuristic\&.
96 .RE
97 .PP
98 \-\-minimal
99 .RS 4
100 Spend extra time to make sure the smallest possible diff is produced\&.
101 .RE
102 .PP
103 \-\-patience
104 .RS 4
105 Generate a diff using the "patience diff" algorithm\&.
106 .RE
107 .PP
108 \-\-histogram
109 .RS 4
110 Generate a diff using the "histogram diff" algorithm\&.
111 .RE
112 .PP
113 \-\-anchored=<text>
114 .RS 4
115 Generate a diff using the "anchored diff" algorithm\&.
116 .sp
117 This option may be specified more than once\&.
118 .sp
119 If a line exists in both the source and destination, exists only once, and starts with this text, this algorithm attempts to prevent it from appearing as a deletion or addition in the output\&. It uses the "patience diff" algorithm internally\&.
120 .RE
121 .PP
122 \-\-diff\-algorithm={patience|minimal|histogram|myers}
123 .RS 4
124 Choose a diff algorithm\&. The variants are as follows:
125 .PP
126 \fBdefault\fR, \fBmyers\fR
127 .RS 4
128 The basic greedy diff algorithm\&. Currently, this is the default\&.
129 .RE
130 .PP
131 \fBminimal\fR
132 .RS 4
133 Spend extra time to make sure the smallest possible diff is produced\&.
134 .RE
135 .PP
136 \fBpatience\fR
137 .RS 4
138 Use "patience diff" algorithm when generating patches\&.
139 .RE
140 .PP
141 \fBhistogram\fR
142 .RS 4
143 This algorithm extends the patience algorithm to "support low\-occurrence common elements"\&.
144 .RE
145 .sp
146 For instance, if you configured the
147 \fBdiff\&.algorithm\fR
148 variable to a non\-default value and want to use the default one, then you have to use
149 \fB\-\-diff\-algorithm=default\fR
150 option\&.
151 .RE
152 .PP
153 \-\-stat[=<width>[,<name\-width>[,<count>]]]
154 .RS 4
155 Generate a diffstat\&. By default, as much space as necessary will be used for the filename part, and the rest for the graph part\&. Maximum width defaults to terminal width, or 80 columns if not connected to a terminal, and can be overridden by
156 \fB<width>\fR\&. The width of the filename part can be limited by giving another width
157 \fB<name\-width>\fR
158 after a comma\&. The width of the graph part can be limited by using
159 \fB\-\-stat\-graph\-width=<width>\fR
160 (affects all commands generating a stat graph) or by setting
161 \fBdiff\&.statGraphWidth=<width>\fR
162 (does not affect
163 \fBgit format\-patch\fR)\&. By giving a third parameter
164 \fB<count>\fR, you can limit the output to the first
165 \fB<count>\fR
166 lines, followed by
167 \fB\&.\&.\&.\fR
168 if there are more\&.
169 .sp
170 These parameters can also be set individually with
171 \fB\-\-stat\-width=<width>\fR,
172 \fB\-\-stat\-name\-width=<name\-width>\fR
173 and
174 \fB\-\-stat\-count=<count>\fR\&.
175 .RE
176 .PP
177 \-\-compact\-summary
178 .RS 4
179 Output a condensed summary of extended header information such as file creations or deletions ("new" or "gone", optionally "+l" if it\(cqs a symlink) and mode changes ("+x" or "\-x" for adding or removing executable bit respectively) in diffstat\&. The information is put between the filename part and the graph part\&. Implies
180 \fB\-\-stat\fR\&.
181 .RE
182 .PP
183 \-\-numstat
184 .RS 4
185 Similar to
186 \fB\-\-stat\fR, but shows number of added and deleted lines in decimal notation and pathname without abbreviation, to make it more machine friendly\&. For binary files, outputs two
187 \fB\-\fR
188 instead of saying
189 \fB0 0\fR\&.
190 .RE
191 .PP
192 \-\-shortstat
193 .RS 4
194 Output only the last line of the
195 \fB\-\-stat\fR
196 format containing total number of modified files, as well as number of added and deleted lines\&.
197 .RE
198 .PP
199 \-X[<param1,param2,\&...>], \-\-dirstat[=<param1,param2,\&...>]
200 .RS 4
201 Output the distribution of relative amount of changes for each sub\-directory\&. The behavior of
202 \fB\-\-dirstat\fR
203 can be customized by passing it a comma separated list of parameters\&. The defaults are controlled by the
204 \fBdiff\&.dirstat\fR
205 configuration variable (see
206 \fBgit-config\fR(1))\&. The following parameters are available:
207 .PP
208 \fBchanges\fR
209 .RS 4
210 Compute the dirstat numbers by counting the lines that have been removed from the source, or added to the destination\&. This ignores the amount of pure code movements within a file\&. In other words, rearranging lines in a file is not counted as much as other changes\&. This is the default behavior when no parameter is given\&.
211 .RE
212 .PP
213 \fBlines\fR
214 .RS 4
215 Compute the dirstat numbers by doing the regular line\-based diff analysis, and summing the removed/added line counts\&. (For binary files, count 64\-byte chunks instead, since binary files have no natural concept of lines)\&. This is a more expensive
216 \fB\-\-dirstat\fR
217 behavior than the
218 \fBchanges\fR
219 behavior, but it does count rearranged lines within a file as much as other changes\&. The resulting output is consistent with what you get from the other
220 \fB\-\-*stat\fR
221 options\&.
222 .RE
223 .PP
224 \fBfiles\fR
225 .RS 4
226 Compute the dirstat numbers by counting the number of files changed\&. Each changed file counts equally in the dirstat analysis\&. This is the computationally cheapest
227 \fB\-\-dirstat\fR
228 behavior, since it does not have to look at the file contents at all\&.
229 .RE
230 .PP
231 \fBcumulative\fR
232 .RS 4
233 Count changes in a child directory for the parent directory as well\&. Note that when using
234 \fBcumulative\fR, the sum of the percentages reported may exceed 100%\&. The default (non\-cumulative) behavior can be specified with the
235 \fBnoncumulative\fR
236 parameter\&.
237 .RE
238 .PP
239 <limit>
240 .RS 4
241 An integer parameter specifies a cut\-off percent (3% by default)\&. Directories contributing less than this percentage of the changes are not shown in the output\&.
242 .RE
243 .sp
244 Example: The following will count changed files, while ignoring directories with less than 10% of the total amount of changed files, and accumulating child directory counts in the parent directories:
245 \fB\-\-dirstat=files,10,cumulative\fR\&.
246 .RE
247 .PP
248 \-\-cumulative
249 .RS 4
250 Synonym for \-\-dirstat=cumulative
251 .RE
252 .PP
253 \-\-dirstat\-by\-file[=<param1,param2>\&...]
254 .RS 4
255 Synonym for \-\-dirstat=files,param1,param2\&...
256 .RE
257 .PP
258 \-\-summary
259 .RS 4
260 Output a condensed summary of extended header information such as creations, renames and mode changes\&.
261 .RE
262 .PP
263 \-\-patch\-with\-stat
264 .RS 4
265 Synonym for
266 \fB\-p \-\-stat\fR\&.
267 .RE
268 .PP
269 \-z
270 .RS 4
271 When
272 \fB\-\-raw\fR,
273 \fB\-\-numstat\fR,
274 \fB\-\-name\-only\fR
275 or
276 \fB\-\-name\-status\fR
277 has been given, do not munge pathnames and use NULs as output field terminators\&.
278 .sp
279 Without this option, pathnames with "unusual" characters are quoted as explained for the configuration variable
280 \fBcore\&.quotePath\fR
281 (see
282 \fBgit-config\fR(1))\&.
283 .RE
284 .PP
285 \-\-name\-only
286 .RS 4
287 Show only names of changed files\&. The file names are often encoded in UTF\-8\&. For more information see the discussion about encoding in the
288 \fBgit-log\fR(1)
289 manual page\&.
290 .RE
291 .PP
292 \-\-name\-status
293 .RS 4
294 Show only names and status of changed files\&. See the description of the
295 \fB\-\-diff\-filter\fR
296 option on what the status letters mean\&. Just like
297 \fB\-\-name\-only\fR
298 the file names are often encoded in UTF\-8\&.
299 .RE
300 .PP
301 \-\-submodule[=<format>]
302 .RS 4
303 Specify how differences in submodules are shown\&. When specifying
304 \fB\-\-submodule=short\fR
305 the
306 \fIshort\fR
307 format is used\&. This format just shows the names of the commits at the beginning and end of the range\&. When
308 \fB\-\-submodule\fR
309 or
310 \fB\-\-submodule=log\fR
311 is specified, the
312 \fIlog\fR
313 format is used\&. This format lists the commits in the range like
314 \fBgit-submodule\fR(1)
315 \fBsummary\fR
316 does\&. When
317 \fB\-\-submodule=diff\fR
318 is specified, the
319 \fIdiff\fR
320 format is used\&. This format shows an inline diff of the changes in the submodule contents between the commit range\&. Defaults to
321 \fBdiff\&.submodule\fR
322 or the
323 \fIshort\fR
324 format if the config option is unset\&.
325 .RE
326 .PP
327 \-\-color[=<when>]
328 .RS 4
329 Show colored diff\&.
330 \fB\-\-color\fR
331 (i\&.e\&. without
332 \fI=<when>\fR) is the same as
333 \fB\-\-color=always\fR\&.
334 \fI<when>\fR
335 can be one of
336 \fBalways\fR,
337 \fBnever\fR, or
338 \fBauto\fR\&.
339 .RE
340 .PP
341 \-\-no\-color
342 .RS 4
343 Turn off colored diff\&. It is the same as
344 \fB\-\-color=never\fR\&.
345 .RE
346 .PP
347 \-\-color\-moved[=<mode>]
348 .RS 4
349 Moved lines of code are colored differently\&. The <mode> defaults to
350 \fIno\fR
351 if the option is not given and to
352 \fIzebra\fR
353 if the option with no mode is given\&. The mode must be one of:
354 .PP
355 no
356 .RS 4
357 Moved lines are not highlighted\&.
358 .RE
359 .PP
360 default
361 .RS 4
362 Is a synonym for
363 \fBzebra\fR\&. This may change to a more sensible mode in the future\&.
364 .RE
365 .PP
366 plain
367 .RS 4
368 Any line that is added in one location and was removed in another location will be colored with
369 \fIcolor\&.diff\&.newMoved\fR\&. Similarly
370 \fIcolor\&.diff\&.oldMoved\fR
371 will be used for removed lines that are added somewhere else in the diff\&. This mode picks up any moved line, but it is not very useful in a review to determine if a block of code was moved without permutation\&.
372 .RE
373 .PP
374 blocks
375 .RS 4
376 Blocks of moved text of at least 20 alphanumeric characters are detected greedily\&. The detected blocks are painted using either the
377 \fIcolor\&.diff\&.{old,new}Moved\fR
378 color\&. Adjacent blocks cannot be told apart\&.
379 .RE
380 .PP
381 zebra
382 .RS 4
383 Blocks of moved text are detected as in
384 \fIblocks\fR
385 mode\&. The blocks are painted using either the
386 \fIcolor\&.diff\&.{old,new}Moved\fR
387 color or
388 \fIcolor\&.diff\&.{old,new}MovedAlternative\fR\&. The change between the two colors indicates that a new block was detected\&.
389 .RE
390 .PP
391 dimmed\-zebra
392 .RS 4
393 Similar to
394 \fIzebra\fR, but additional dimming of uninteresting parts of moved code is performed\&. The bordering lines of two adjacent blocks are considered interesting, the rest is uninteresting\&.
395 \fBdimmed_zebra\fR
396 is a deprecated synonym\&.
397 .RE
398 .RE
399 .PP
400 \-\-no\-color\-moved
401 .RS 4
402 Turn off move detection\&. This can be used to override configuration settings\&. It is the same as
403 \fB\-\-color\-moved=no\fR\&.
404 .RE
405 .PP
406 \-\-color\-moved\-ws=<modes>
407 .RS 4
408 This configures how whitespace is ignored when performing the move detection for
409 \fB\-\-color\-moved\fR\&. These modes can be given as a comma separated list:
410 .PP
411 no
412 .RS 4
413 Do not ignore whitespace when performing move detection\&.
414 .RE
415 .PP
416 ignore\-space\-at\-eol
417 .RS 4
418 Ignore changes in whitespace at EOL\&.
419 .RE
420 .PP
421 ignore\-space\-change
422 .RS 4
423 Ignore changes in amount of whitespace\&. This ignores whitespace at line end, and considers all other sequences of one or more whitespace characters to be equivalent\&.
424 .RE
425 .PP
426 ignore\-all\-space
427 .RS 4
428 Ignore whitespace when comparing lines\&. This ignores differences even if one line has whitespace where the other line has none\&.
429 .RE
430 .PP
431 allow\-indentation\-change
432 .RS 4
433 Initially ignore any whitespace in the move detection, then group the moved code blocks only into a block if the change in whitespace is the same per line\&. This is incompatible with the other modes\&.
434 .RE
435 .RE
436 .PP
437 \-\-no\-color\-moved\-ws
438 .RS 4
439 Do not ignore whitespace when performing move detection\&. This can be used to override configuration settings\&. It is the same as
440 \fB\-\-color\-moved\-ws=no\fR\&.
441 .RE
442 .PP
443 \-\-word\-diff[=<mode>]
444 .RS 4
445 Show a word diff, using the <mode> to delimit changed words\&. By default, words are delimited by whitespace; see
446 \fB\-\-word\-diff\-regex\fR
447 below\&. The <mode> defaults to
448 \fIplain\fR, and must be one of:
449 .PP
450 color
451 .RS 4
452 Highlight changed words using only colors\&. Implies
453 \fB\-\-color\fR\&.
454 .RE
455 .PP
456 plain
457 .RS 4
458 Show words as
459 \fB[\-removed\-]\fR
460 and
461 \fB{+added+}\fR\&. Makes no attempts to escape the delimiters if they appear in the input, so the output may be ambiguous\&.
462 .RE
463 .PP
464 porcelain
465 .RS 4
466 Use a special line\-based format intended for script consumption\&. Added/removed/unchanged runs are printed in the usual unified diff format, starting with a
467 \fB+\fR/\fB\-\fR/` ` character at the beginning of the line and extending to the end of the line\&. Newlines in the input are represented by a tilde
468 \fB~\fR
469 on a line of its own\&.
470 .RE
471 .PP
472 none
473 .RS 4
474 Disable word diff again\&.
475 .RE
476 .sp
477 Note that despite the name of the first mode, color is used to highlight the changed parts in all modes if enabled\&.
478 .RE
479 .PP
480 \-\-word\-diff\-regex=<regex>
481 .RS 4
482 Use <regex> to decide what a word is, instead of considering runs of non\-whitespace to be a word\&. Also implies
483 \fB\-\-word\-diff\fR
484 unless it was already enabled\&.
485 .sp
486 Every non\-overlapping match of the <regex> is considered a word\&. Anything between these matches is considered whitespace and ignored(!) for the purposes of finding differences\&. You may want to append
487 \fB|[^[:space:]]\fR
488 to your regular expression to make sure that it matches all non\-whitespace characters\&. A match that contains a newline is silently truncated(!) at the newline\&.
489 .sp
490 For example,
491 \fB\-\-word\-diff\-regex=\&.\fR
492 will treat each character as a word and, correspondingly, show differences character by character\&.
493 .sp
494 The regex can also be set via a diff driver or configuration option, see
495 \fBgitattributes\fR(5)
496 or
497 \fBgit-config\fR(1)\&. Giving it explicitly overrides any diff driver or configuration setting\&. Diff drivers override configuration settings\&.
498 .RE
499 .PP
500 \-\-color\-words[=<regex>]
501 .RS 4
502 Equivalent to
503 \fB\-\-word\-diff=color\fR
504 plus (if a regex was specified)
505 \fB\-\-word\-diff\-regex=<regex>\fR\&.
506 .RE
507 .PP
508 \-\-no\-renames
509 .RS 4
510 Turn off rename detection, even when the configuration file gives the default to do so\&.
511 .RE
512 .PP
513 \-\-[no\-]rename\-empty
514 .RS 4
515 Whether to use empty blobs as rename source\&.
516 .RE
517 .PP
518 \-\-check
519 .RS 4
520 Warn if changes introduce conflict markers or whitespace errors\&. What are considered whitespace errors is controlled by
521 \fBcore\&.whitespace\fR
522 configuration\&. By default, trailing whitespaces (including lines that consist solely of whitespaces) and a space character that is immediately followed by a tab character inside the initial indent of the line are considered whitespace errors\&. Exits with non\-zero status if problems are found\&. Not compatible with \-\-exit\-code\&.
523 .RE
524 .PP
525 \-\-ws\-error\-highlight=<kind>
526 .RS 4
527 Highlight whitespace errors in the
528 \fBcontext\fR,
529 \fBold\fR
530 or
531 \fBnew\fR
532 lines of the diff\&. Multiple values are separated by comma,
533 \fBnone\fR
534 resets previous values,
535 \fBdefault\fR
536 reset the list to
537 \fBnew\fR
538 and
539 \fBall\fR
540 is a shorthand for
541 \fBold,new,context\fR\&. When this option is not given, and the configuration variable
542 \fBdiff\&.wsErrorHighlight\fR
543 is not set, only whitespace errors in
544 \fBnew\fR
545 lines are highlighted\&. The whitespace errors are colored with
546 \fBcolor\&.diff\&.whitespace\fR\&.
547 .RE
548 .PP
549 \-\-full\-index
550 .RS 4
551 Instead of the first handful of characters, show the full pre\- and post\-image blob object names on the "index" line when generating patch format output\&.
552 .RE
553 .PP
554 \-\-binary
555 .RS 4
556 In addition to
557 \fB\-\-full\-index\fR, output a binary diff that can be applied with
558 \fBgit\-apply\fR\&. Implies
559 \fB\-\-patch\fR\&.
560 .RE
561 .PP
562 \-\-abbrev[=<n>]
563 .RS 4
564 Instead of showing the full 40\-byte hexadecimal object name in diff\-raw format output and diff\-tree header lines, show the shortest prefix that is at least
565 \fI<n>\fR
566 hexdigits long that uniquely refers the object\&. In diff\-patch output format,
567 \fB\-\-full\-index\fR
568 takes higher precedence, i\&.e\&. if
569 \fB\-\-full\-index\fR
570 is specified, full blob names will be shown regardless of
571 \fB\-\-abbrev\fR\&. Non default number of digits can be specified with
572 \fB\-\-abbrev=<n>\fR\&.
573 .RE
574 .PP
575 \-B[<n>][/<m>], \-\-break\-rewrites[=[<n>][/<m>]]
576 .RS 4
577 Break complete rewrite changes into pairs of delete and create\&. This serves two purposes:
578 .sp
579 It affects the way a change that amounts to a total rewrite of a file not as a series of deletion and insertion mixed together with a very few lines that happen to match textually as the context, but as a single deletion of everything old followed by a single insertion of everything new, and the number
580 \fBm\fR
581 controls this aspect of the \-B option (defaults to 60%)\&.
582 \fB\-B/70%\fR
583 specifies that less than 30% of the original should remain in the result for Git to consider it a total rewrite (i\&.e\&. otherwise the resulting patch will be a series of deletion and insertion mixed together with context lines)\&.
584 .sp
585 When used with \-M, a totally\-rewritten file is also considered as the source of a rename (usually \-M only considers a file that disappeared as the source of a rename), and the number
586 \fBn\fR
587 controls this aspect of the \-B option (defaults to 50%)\&.
588 \fB\-B20%\fR
589 specifies that a change with addition and deletion compared to 20% or more of the file\(cqs size are eligible for being picked up as a possible source of a rename to another file\&.
590 .RE
591 .PP
592 \-M[<n>], \-\-find\-renames[=<n>]
593 .RS 4
594 Detect renames\&. If
595 \fBn\fR
596 is specified, it is a threshold on the similarity index (i\&.e\&. amount of addition/deletions compared to the file\(cqs size)\&. For example,
597 \fB\-M90%\fR
598 means Git should consider a delete/add pair to be a rename if more than 90% of the file hasn\(cqt changed\&. Without a
599 \fB%\fR
600 sign, the number is to be read as a fraction, with a decimal point before it\&. I\&.e\&.,
601 \fB\-M5\fR
602 becomes 0\&.5, and is thus the same as
603 \fB\-M50%\fR\&. Similarly,
604 \fB\-M05\fR
605 is the same as
606 \fB\-M5%\fR\&. To limit detection to exact renames, use
607 \fB\-M100%\fR\&. The default similarity index is 50%\&.
608 .RE
609 .PP
610 \-C[<n>], \-\-find\-copies[=<n>]
611 .RS 4
612 Detect copies as well as renames\&. See also
613 \fB\-\-find\-copies\-harder\fR\&. If
614 \fBn\fR
615 is specified, it has the same meaning as for
616 \fB\-M<n>\fR\&.
617 .RE
618 .PP
619 \-\-find\-copies\-harder
620 .RS 4
621 For performance reasons, by default,
622 \fB\-C\fR
623 option finds copies only if the original file of the copy was modified in the same changeset\&. This flag makes the command inspect unmodified files as candidates for the source of copy\&. This is a very expensive operation for large projects, so use it with caution\&. Giving more than one
624 \fB\-C\fR
625 option has the same effect\&.
626 .RE
627 .PP
628 \-D, \-\-irreversible\-delete
629 .RS 4
630 Omit the preimage for deletes, i\&.e\&. print only the header but not the diff between the preimage and
631 \fB/dev/null\fR\&. The resulting patch is not meant to be applied with
632 \fBpatch\fR
633 or
634 \fBgit apply\fR; this is solely for people who want to just concentrate on reviewing the text after the change\&. In addition, the output obviously lacks enough information to apply such a patch in reverse, even manually, hence the name of the option\&.
635 .sp
636 When used together with
637 \fB\-B\fR, omit also the preimage in the deletion part of a delete/create pair\&.
638 .RE
639 .PP
640 \-l<num>
641 .RS 4
642 The
643 \fB\-M\fR
644 and
645 \fB\-C\fR
646 options involve some preliminary steps that can detect subsets of renames/copies cheaply, followed by an exhaustive fallback portion that compares all remaining unpaired destinations to all relevant sources\&. (For renames, only remaining unpaired sources are relevant; for copies, all original sources are relevant\&.) For N sources and destinations, this exhaustive check is O(N^2)\&. This option prevents the exhaustive portion of rename/copy detection from running if the number of source/destination files involved exceeds the specified number\&. Defaults to diff\&.renameLimit\&. Note that a value of 0 is treated as unlimited\&.
647 .RE
648 .PP
649 \-\-diff\-filter=[(A|C|D|M|R|T|U|X|B)\&...[*]]
650 .RS 4
651 Select only files that are Added (\fBA\fR), Copied (\fBC\fR), Deleted (\fBD\fR), Modified (\fBM\fR), Renamed (\fBR\fR), have their type (i\&.e\&. regular file, symlink, submodule, \&...) changed (\fBT\fR), are Unmerged (\fBU\fR), are Unknown (\fBX\fR), or have had their pairing Broken (\fBB\fR)\&. Any combination of the filter characters (including none) can be used\&. When
652 \fB*\fR
653 (All\-or\-none) is added to the combination, all paths are selected if there is any file that matches other criteria in the comparison; if there is no file that matches other criteria, nothing is selected\&.
654 .sp
655 Also, these upper\-case letters can be downcased to exclude\&. E\&.g\&.
656 \fB\-\-diff\-filter=ad\fR
657 excludes added and deleted paths\&.
658 .sp
659 Note that not all diffs can feature all types\&. For instance, copied and renamed entries cannot appear if detection for those types is disabled\&.
660 .RE
661 .PP
662 \-S<string>
663 .RS 4
664 Look for differences that change the number of occurrences of the specified string (i\&.e\&. addition/deletion) in a file\&. Intended for the scripter\(cqs use\&.
665 .sp
666 It is useful when you\(cqre looking for an exact block of code (like a struct), and want to know the history of that block since it first came into being: use the feature iteratively to feed the interesting block in the preimage back into
667 \fB\-S\fR, and keep going until you get the very first version of the block\&.
668 .sp
669 Binary files are searched as well\&.
670 .RE
671 .PP
672 \-G<regex>
673 .RS 4
674 Look for differences whose patch text contains added/removed lines that match <regex>\&.
675 .sp
676 To illustrate the difference between
677 \fB\-S<regex> \-\-pickaxe\-regex\fR
678 and
679 \fB\-G<regex>\fR, consider a commit with the following diff in the same file:
680 .sp
681 .if n \{\
682 .RS 4
683 .\}
684 .nf
685 + return frotz(nitfol, two\->ptr, 1, 0);
686 \&.\&.\&.
687 \- hit = frotz(nitfol, mf2\&.ptr, 1, 0);
688 .fi
689 .if n \{\
690 .RE
691 .\}
692 .sp
693 While
694 \fBgit log \-G"frotz\e(nitfol"\fR
695 will show this commit,
696 \fBgit log \-S"frotz\e(nitfol" \-\-pickaxe\-regex\fR
697 will not (because the number of occurrences of that string did not change)\&.
698 .sp
699 Unless
700 \fB\-\-text\fR
701 is supplied patches of binary files without a textconv filter will be ignored\&.
702 .sp
703 See the
704 \fIpickaxe\fR
705 entry in
706 \fBgitdiffcore\fR(7)
707 for more information\&.
708 .RE
709 .PP
710 \-\-find\-object=<object\-id>
711 .RS 4
712 Look for differences that change the number of occurrences of the specified object\&. Similar to
713 \fB\-S\fR, just the argument is different in that it doesn\(cqt search for a specific string but for a specific object id\&.
714 .sp
715 The object can be a blob or a submodule commit\&. It implies the
716 \fB\-t\fR
717 option in
718 \fBgit\-log\fR
719 to also find trees\&.
720 .RE
721 .PP
722 \-\-pickaxe\-all
723 .RS 4
724 When
725 \fB\-S\fR
726 or
727 \fB\-G\fR
728 finds a change, show all the changes in that changeset, not just the files that contain the change in <string>\&.
729 .RE
730 .PP
731 \-\-pickaxe\-regex
732 .RS 4
733 Treat the <string> given to
734 \fB\-S\fR
735 as an extended POSIX regular expression to match\&.
736 .RE
737 .PP
738 \-O<orderfile>
739 .RS 4
740 Control the order in which files appear in the output\&. This overrides the
741 \fBdiff\&.orderFile\fR
742 configuration variable (see
743 \fBgit-config\fR(1))\&. To cancel
744 \fBdiff\&.orderFile\fR, use
745 \fB\-O/dev/null\fR\&.
746 .sp
747 The output order is determined by the order of glob patterns in <orderfile>\&. All files with pathnames that match the first pattern are output first, all files with pathnames that match the second pattern (but not the first) are output next, and so on\&. All files with pathnames that do not match any pattern are output last, as if there was an implicit match\-all pattern at the end of the file\&. If multiple pathnames have the same rank (they match the same pattern but no earlier patterns), their output order relative to each other is the normal order\&.
748 .sp
749 <orderfile> is parsed as follows:
750 .sp
751 .RS 4
752 .ie n \{\
753 \h'-04'\(bu\h'+03'\c
754 .\}
755 .el \{\
756 .sp -1
757 .IP \(bu 2.3
758 .\}
759 Blank lines are ignored, so they can be used as separators for readability\&.
760 .RE
761 .sp
762 .RS 4
763 .ie n \{\
764 \h'-04'\(bu\h'+03'\c
765 .\}
766 .el \{\
767 .sp -1
768 .IP \(bu 2.3
769 .\}
770 Lines starting with a hash ("\fB#\fR") are ignored, so they can be used for comments\&. Add a backslash ("\fB\e\fR") to the beginning of the pattern if it starts with a hash\&.
771 .RE
772 .sp
773 .RS 4
774 .ie n \{\
775 \h'-04'\(bu\h'+03'\c
776 .\}
777 .el \{\
778 .sp -1
779 .IP \(bu 2.3
780 .\}
781 Each other line contains a single pattern\&.
782 .RE
783 .sp
784 Patterns have the same syntax and semantics as patterns used for fnmatch(3) without the FNM_PATHNAME flag, except a pathname also matches a pattern if removing any number of the final pathname components matches the pattern\&. For example, the pattern "\fBfoo*bar\fR" matches "\fBfooasdfbar\fR" and "\fBfoo/bar/baz/asdf\fR" but not "\fBfoobarx\fR"\&.
785 .RE
786 .PP
787 \-\-skip\-to=<file>, \-\-rotate\-to=<file>
788 .RS 4
789 Discard the files before the named <file> from the output (i\&.e\&.
790 \fIskip to\fR), or move them to the end of the output (i\&.e\&.
791 \fIrotate to\fR)\&. These were invented primarily for use of the
792 \fBgit difftool\fR
793 command, and may not be very useful otherwise\&.
794 .RE
795 .PP
796 \-R
797 .RS 4
798 Swap two inputs; that is, show differences from index or on\-disk file to tree contents\&.
799 .RE
800 .PP
801 \-\-relative[=<path>], \-\-no\-relative
802 .RS 4
803 When run from a subdirectory of the project, it can be told to exclude changes outside the directory and show pathnames relative to it with this option\&. When you are not in a subdirectory (e\&.g\&. in a bare repository), you can name which subdirectory to make the output relative to by giving a <path> as an argument\&.
804 \fB\-\-no\-relative\fR
805 can be used to countermand both
806 \fBdiff\&.relative\fR
807 config option and previous
808 \fB\-\-relative\fR\&.
809 .RE
810 .PP
811 \-a, \-\-text
812 .RS 4
813 Treat all files as text\&.
814 .RE
815 .PP
816 \-\-ignore\-cr\-at\-eol
817 .RS 4
818 Ignore carriage\-return at the end of line when doing a comparison\&.
819 .RE
820 .PP
821 \-\-ignore\-space\-at\-eol
822 .RS 4
823 Ignore changes in whitespace at EOL\&.
824 .RE
825 .PP
826 \-b, \-\-ignore\-space\-change
827 .RS 4
828 Ignore changes in amount of whitespace\&. This ignores whitespace at line end, and considers all other sequences of one or more whitespace characters to be equivalent\&.
829 .RE
830 .PP
831 \-w, \-\-ignore\-all\-space
832 .RS 4
833 Ignore whitespace when comparing lines\&. This ignores differences even if one line has whitespace where the other line has none\&.
834 .RE
835 .PP
836 \-\-ignore\-blank\-lines
837 .RS 4
838 Ignore changes whose lines are all blank\&.
839 .RE
840 .PP
841 \-I<regex>, \-\-ignore\-matching\-lines=<regex>
842 .RS 4
843 Ignore changes whose all lines match <regex>\&. This option may be specified more than once\&.
844 .RE
845 .PP
846 \-\-inter\-hunk\-context=<lines>
847 .RS 4
848 Show the context between diff hunks, up to the specified number of lines, thereby fusing hunks that are close to each other\&. Defaults to
849 \fBdiff\&.interHunkContext\fR
850 or 0 if the config option is unset\&.
851 .RE
852 .PP
853 \-W, \-\-function\-context
854 .RS 4
855 Show whole function as context lines for each change\&. The function names are determined in the same way as
856 \fBgit diff\fR
857 works out patch hunk headers (see
858 \fIDefining a custom hunk\-header\fR
859 in
860 \fBgitattributes\fR(5))\&.
861 .RE
862 .PP
863 \-\-exit\-code
864 .RS 4
865 Make the program exit with codes similar to diff(1)\&. That is, it exits with 1 if there were differences and 0 means no differences\&.
866 .RE
867 .PP
868 \-\-quiet
869 .RS 4
870 Disable all output of the program\&. Implies
871 \fB\-\-exit\-code\fR\&.
872 .RE
873 .PP
874 \-\-ext\-diff
875 .RS 4
876 Allow an external diff helper to be executed\&. If you set an external diff driver with
877 \fBgitattributes\fR(5), you need to use this option with
878 \fBgit-log\fR(1)
879 and friends\&.
880 .RE
881 .PP
882 \-\-no\-ext\-diff
883 .RS 4
884 Disallow external diff drivers\&.
885 .RE
886 .PP
887 \-\-textconv, \-\-no\-textconv
888 .RS 4
889 Allow (or disallow) external text conversion filters to be run when comparing binary files\&. See
890 \fBgitattributes\fR(5)
891 for details\&. Because textconv filters are typically a one\-way conversion, the resulting diff is suitable for human consumption, but cannot be applied\&. For this reason, textconv filters are enabled by default only for
892 \fBgit-diff\fR(1)
893 and
894 \fBgit-log\fR(1), but not for
895 \fBgit-format-patch\fR(1)
896 or diff plumbing commands\&.
897 .RE
898 .PP
899 \-\-ignore\-submodules[=<when>]
900 .RS 4
901 Ignore changes to submodules in the diff generation\&. <when> can be either "none", "untracked", "dirty" or "all", which is the default\&. Using "none" will consider the submodule modified when it either contains untracked or modified files or its HEAD differs from the commit recorded in the superproject and can be used to override any settings of the
902 \fIignore\fR
903 option in
904 \fBgit-config\fR(1)
905 or
906 \fBgitmodules\fR(5)\&. When "untracked" is used submodules are not considered dirty when they only contain untracked content (but they are still scanned for modified content)\&. Using "dirty" ignores all changes to the work tree of submodules, only changes to the commits stored in the superproject are shown (this was the behavior until 1\&.7\&.0)\&. Using "all" hides all changes to submodules\&.
907 .RE
908 .PP
909 \-\-src\-prefix=<prefix>
910 .RS 4
911 Show the given source prefix instead of "a/"\&.
912 .RE
913 .PP
914 \-\-dst\-prefix=<prefix>
915 .RS 4
916 Show the given destination prefix instead of "b/"\&.
917 .RE
918 .PP
919 \-\-no\-prefix
920 .RS 4
921 Do not show any source or destination prefix\&.
922 .RE
923 .PP
924 \-\-default\-prefix
925 .RS 4
926 Use the default source and destination prefixes ("a/" and "b/")\&. This is usually the default already, but may be used to override config such as
927 \fBdiff\&.noprefix\fR\&.
928 .RE
929 .PP
930 \-\-line\-prefix=<prefix>
931 .RS 4
932 Prepend an additional prefix to every line of output\&.
933 .RE
934 .PP
935 \-\-ita\-invisible\-in\-index
936 .RS 4
937 By default entries added by "git add \-N" appear as an existing empty file in "git diff" and a new file in "git diff \-\-cached"\&. This option makes the entry appear as a new file in "git diff" and non\-existent in "git diff \-\-cached"\&. This option could be reverted with
938 \fB\-\-ita\-visible\-in\-index\fR\&. Both options are experimental and could be removed in future\&.
939 .RE
940 .sp
941 For more detailed explanation on these common options, see also \fBgitdiffcore\fR(7)\&.
942 .PP
943 <tree\-ish>
944 .RS 4
945 The id of a tree object to diff against\&.
946 .RE
947 .PP
948 \-\-cached
949 .RS 4
950 Do not consider the on\-disk file at all\&.
951 .RE
952 .PP
953 \-\-merge\-base
954 .RS 4
955 Instead of comparing <tree\-ish> directly, use the merge base between <tree\-ish> and HEAD instead\&. <tree\-ish> must be a commit\&.
956 .RE
957 .PP
958 \-m
959 .RS 4
960 By default, files recorded in the index but not checked out are reported as deleted\&. This flag makes
961 \fIgit diff\-index\fR
962 say that all non\-checked\-out files are up to date\&.
963 .RE
964 .SH "RAW OUTPUT FORMAT"
965 .sp
966 The raw output format from "git\-diff\-index", "git\-diff\-tree", "git\-diff\-files" and "git diff \-\-raw" are very similar\&.
967 .sp
968 These commands all compare two sets of things; what is compared differs:
969 .PP
970 git\-diff\-index <tree\-ish>
971 .RS 4
972 compares the <tree\-ish> and the files on the filesystem\&.
973 .RE
974 .PP
975 git\-diff\-index \-\-cached <tree\-ish>
976 .RS 4
977 compares the <tree\-ish> and the index\&.
978 .RE
979 .PP
980 git\-diff\-tree [\-r] <tree\-ish\-1> <tree\-ish\-2> [<pattern>\&...]
981 .RS 4
982 compares the trees named by the two arguments\&.
983 .RE
984 .PP
985 git\-diff\-files [<pattern>\&...]
986 .RS 4
987 compares the index and the files on the filesystem\&.
988 .RE
989 .sp
990 The "git\-diff\-tree" command begins its output by printing the hash of what is being compared\&. After that, all the commands print one output line per changed file\&.
991 .sp
992 An output line is formatted this way:
993 .sp
994 .if n \{\
995 .RS 4
996 .\}
997 .nf
998 in\-place edit :100644 100644 bcd1234 0123456 M file0
999 copy\-edit :100644 100644 abcd123 1234567 C68 file1 file2
1000 rename\-edit :100644 100644 abcd123 1234567 R86 file1 file3
1001 create :000000 100644 0000000 1234567 A file4
1002 delete :100644 000000 1234567 0000000 D file5
1003 unmerged :000000 000000 0000000 0000000 U file6
1004 .fi
1005 .if n \{\
1006 .RE
1007 .\}
1008 .sp
1009 .sp
1010 That is, from the left to the right:
1011 .sp
1012 .RS 4
1013 .ie n \{\
1014 \h'-04' 1.\h'+01'\c
1015 .\}
1016 .el \{\
1017 .sp -1
1018 .IP " 1." 4.2
1019 .\}
1020 a colon\&.
1021 .RE
1022 .sp
1023 .RS 4
1024 .ie n \{\
1025 \h'-04' 2.\h'+01'\c
1026 .\}
1027 .el \{\
1028 .sp -1
1029 .IP " 2." 4.2
1030 .\}
1031 mode for "src"; 000000 if creation or unmerged\&.
1032 .RE
1033 .sp
1034 .RS 4
1035 .ie n \{\
1036 \h'-04' 3.\h'+01'\c
1037 .\}
1038 .el \{\
1039 .sp -1
1040 .IP " 3." 4.2
1041 .\}
1042 a space\&.
1043 .RE
1044 .sp
1045 .RS 4
1046 .ie n \{\
1047 \h'-04' 4.\h'+01'\c
1048 .\}
1049 .el \{\
1050 .sp -1
1051 .IP " 4." 4.2
1052 .\}
1053 mode for "dst"; 000000 if deletion or unmerged\&.
1054 .RE
1055 .sp
1056 .RS 4
1057 .ie n \{\
1058 \h'-04' 5.\h'+01'\c
1059 .\}
1060 .el \{\
1061 .sp -1
1062 .IP " 5." 4.2
1063 .\}
1064 a space\&.
1065 .RE
1066 .sp
1067 .RS 4
1068 .ie n \{\
1069 \h'-04' 6.\h'+01'\c
1070 .\}
1071 .el \{\
1072 .sp -1
1073 .IP " 6." 4.2
1074 .\}
1075 sha1 for "src"; 0{40} if creation or unmerged\&.
1076 .RE
1077 .sp
1078 .RS 4
1079 .ie n \{\
1080 \h'-04' 7.\h'+01'\c
1081 .\}
1082 .el \{\
1083 .sp -1
1084 .IP " 7." 4.2
1085 .\}
1086 a space\&.
1087 .RE
1088 .sp
1089 .RS 4
1090 .ie n \{\
1091 \h'-04' 8.\h'+01'\c
1092 .\}
1093 .el \{\
1094 .sp -1
1095 .IP " 8." 4.2
1096 .\}
1097 sha1 for "dst"; 0{40} if deletion, unmerged or "work tree out of sync with the index"\&.
1098 .RE
1099 .sp
1100 .RS 4
1101 .ie n \{\
1102 \h'-04' 9.\h'+01'\c
1103 .\}
1104 .el \{\
1105 .sp -1
1106 .IP " 9." 4.2
1107 .\}
1108 a space\&.
1109 .RE
1110 .sp
1111 .RS 4
1112 .ie n \{\
1113 \h'-04'10.\h'+01'\c
1114 .\}
1115 .el \{\
1116 .sp -1
1117 .IP "10." 4.2
1118 .\}
1119 status, followed by optional "score" number\&.
1120 .RE
1121 .sp
1122 .RS 4
1123 .ie n \{\
1124 \h'-04'11.\h'+01'\c
1125 .\}
1126 .el \{\
1127 .sp -1
1128 .IP "11." 4.2
1129 .\}
1130 a tab or a NUL when
1131 \fB\-z\fR
1132 option is used\&.
1133 .RE
1134 .sp
1135 .RS 4
1136 .ie n \{\
1137 \h'-04'12.\h'+01'\c
1138 .\}
1139 .el \{\
1140 .sp -1
1141 .IP "12." 4.2
1142 .\}
1143 path for "src"
1144 .RE
1145 .sp
1146 .RS 4
1147 .ie n \{\
1148 \h'-04'13.\h'+01'\c
1149 .\}
1150 .el \{\
1151 .sp -1
1152 .IP "13." 4.2
1153 .\}
1154 a tab or a NUL when
1155 \fB\-z\fR
1156 option is used; only exists for C or R\&.
1157 .RE
1158 .sp
1159 .RS 4
1160 .ie n \{\
1161 \h'-04'14.\h'+01'\c
1162 .\}
1163 .el \{\
1164 .sp -1
1165 .IP "14." 4.2
1166 .\}
1167 path for "dst"; only exists for C or R\&.
1168 .RE
1169 .sp
1170 .RS 4
1171 .ie n \{\
1172 \h'-04'15.\h'+01'\c
1173 .\}
1174 .el \{\
1175 .sp -1
1176 .IP "15." 4.2
1177 .\}
1178 an LF or a NUL when
1179 \fB\-z\fR
1180 option is used, to terminate the record\&.
1181 .RE
1182 .sp
1183 Possible status letters are:
1184 .sp
1185 .RS 4
1186 .ie n \{\
1187 \h'-04'\(bu\h'+03'\c
1188 .\}
1189 .el \{\
1190 .sp -1
1191 .IP \(bu 2.3
1192 .\}
1193 A: addition of a file
1194 .RE
1195 .sp
1196 .RS 4
1197 .ie n \{\
1198 \h'-04'\(bu\h'+03'\c
1199 .\}
1200 .el \{\
1201 .sp -1
1202 .IP \(bu 2.3
1203 .\}
1204 C: copy of a file into a new one
1205 .RE
1206 .sp
1207 .RS 4
1208 .ie n \{\
1209 \h'-04'\(bu\h'+03'\c
1210 .\}
1211 .el \{\
1212 .sp -1
1213 .IP \(bu 2.3
1214 .\}
1215 D: deletion of a file
1216 .RE
1217 .sp
1218 .RS 4
1219 .ie n \{\
1220 \h'-04'\(bu\h'+03'\c
1221 .\}
1222 .el \{\
1223 .sp -1
1224 .IP \(bu 2.3
1225 .\}
1226 M: modification of the contents or mode of a file
1227 .RE
1228 .sp
1229 .RS 4
1230 .ie n \{\
1231 \h'-04'\(bu\h'+03'\c
1232 .\}
1233 .el \{\
1234 .sp -1
1235 .IP \(bu 2.3
1236 .\}
1237 R: renaming of a file
1238 .RE
1239 .sp
1240 .RS 4
1241 .ie n \{\
1242 \h'-04'\(bu\h'+03'\c
1243 .\}
1244 .el \{\
1245 .sp -1
1246 .IP \(bu 2.3
1247 .\}
1248 T: change in the type of the file (regular file, symbolic link or submodule)
1249 .RE
1250 .sp
1251 .RS 4
1252 .ie n \{\
1253 \h'-04'\(bu\h'+03'\c
1254 .\}
1255 .el \{\
1256 .sp -1
1257 .IP \(bu 2.3
1258 .\}
1259 U: file is unmerged (you must complete the merge before it can be committed)
1260 .RE
1261 .sp
1262 .RS 4
1263 .ie n \{\
1264 \h'-04'\(bu\h'+03'\c
1265 .\}
1266 .el \{\
1267 .sp -1
1268 .IP \(bu 2.3
1269 .\}
1270 X: "unknown" change type (most probably a bug, please report it)
1271 .RE
1272 .sp
1273 Status letters C and R are always followed by a score (denoting the percentage of similarity between the source and target of the move or copy)\&. Status letter M may be followed by a score (denoting the percentage of dissimilarity) for file rewrites\&.
1274 .sp
1275 The sha1 for "dst" is shown as all 0\(cqs if a file on the filesystem is out of sync with the index\&.
1276 .sp
1277 Example:
1278 .sp
1279 .if n \{\
1280 .RS 4
1281 .\}
1282 .nf
1283 :100644 100644 5be4a4a 0000000 M file\&.c
1284 .fi
1285 .if n \{\
1286 .RE
1287 .\}
1288 .sp
1289 .sp
1290 Without the \fB\-z\fR option, pathnames with "unusual" characters are quoted as explained for the configuration variable \fBcore\&.quotePath\fR (see \fBgit-config\fR(1))\&. Using \fB\-z\fR the filename is output verbatim and the line is terminated by a NUL byte\&.
1291 .SH "DIFF FORMAT FOR MERGES"
1292 .sp
1293 "git\-diff\-tree", "git\-diff\-files" and "git\-diff \-\-raw" can take \fB\-c\fR or \fB\-\-cc\fR option to generate diff output also for merge commits\&. The output differs from the format described above in the following way:
1294 .sp
1295 .RS 4
1296 .ie n \{\
1297 \h'-04' 1.\h'+01'\c
1298 .\}
1299 .el \{\
1300 .sp -1
1301 .IP " 1." 4.2
1302 .\}
1303 there is a colon for each parent
1304 .RE
1305 .sp
1306 .RS 4
1307 .ie n \{\
1308 \h'-04' 2.\h'+01'\c
1309 .\}
1310 .el \{\
1311 .sp -1
1312 .IP " 2." 4.2
1313 .\}
1314 there are more "src" modes and "src" sha1
1315 .RE
1316 .sp
1317 .RS 4
1318 .ie n \{\
1319 \h'-04' 3.\h'+01'\c
1320 .\}
1321 .el \{\
1322 .sp -1
1323 .IP " 3." 4.2
1324 .\}
1325 status is concatenated status characters for each parent
1326 .RE
1327 .sp
1328 .RS 4
1329 .ie n \{\
1330 \h'-04' 4.\h'+01'\c
1331 .\}
1332 .el \{\
1333 .sp -1
1334 .IP " 4." 4.2
1335 .\}
1336 no optional "score" number
1337 .RE
1338 .sp
1339 .RS 4
1340 .ie n \{\
1341 \h'-04' 5.\h'+01'\c
1342 .\}
1343 .el \{\
1344 .sp -1
1345 .IP " 5." 4.2
1346 .\}
1347 tab\-separated pathname(s) of the file
1348 .RE
1349 .sp
1350 For \fB\-c\fR and \fB\-\-cc\fR, only the destination or final path is shown even if the file was renamed on any side of history\&. With \fB\-\-combined\-all\-paths\fR, the name of the path in each parent is shown followed by the name of the path in the merge commit\&.
1351 .sp
1352 Examples for \fB\-c\fR and \fB\-\-cc\fR without \fB\-\-combined\-all\-paths\fR:
1353 .sp
1354 .if n \{\
1355 .RS 4
1356 .\}
1357 .nf
1358 ::100644 100644 100644 fabadb8 cc95eb0 4866510 MM desc\&.c
1359 ::100755 100755 100755 52b7a2d 6d1ac04 d2ac7d7 RM bar\&.sh
1360 ::100644 100644 100644 e07d6c5 9042e82 ee91881 RR phooey\&.c
1361 .fi
1362 .if n \{\
1363 .RE
1364 .\}
1365 .sp
1366 .sp
1367 Examples when \fB\-\-combined\-all\-paths\fR added to either \fB\-c\fR or \fB\-\-cc\fR:
1368 .sp
1369 .if n \{\
1370 .RS 4
1371 .\}
1372 .nf
1373 ::100644 100644 100644 fabadb8 cc95eb0 4866510 MM desc\&.c desc\&.c desc\&.c
1374 ::100755 100755 100755 52b7a2d 6d1ac04 d2ac7d7 RM foo\&.sh bar\&.sh bar\&.sh
1375 ::100644 100644 100644 e07d6c5 9042e82 ee91881 RR fooey\&.c fuey\&.c phooey\&.c
1376 .fi
1377 .if n \{\
1378 .RE
1379 .\}
1380 .sp
1381 .sp
1382 Note that \fIcombined diff\fR lists only files which were modified from all parents\&.
1383 .SH "GENERATING PATCH TEXT WITH \-P"
1384 .sp
1385 Running \fBgit-diff\fR(1), \fBgit-log\fR(1), \fBgit-show\fR(1), \fBgit-diff-index\fR(1), \fBgit-diff-tree\fR(1), or \fBgit-diff-files\fR(1) with the \fB\-p\fR option produces patch text\&. You can customize the creation of patch text via the \fBGIT_EXTERNAL_DIFF\fR and the \fBGIT_DIFF_OPTS\fR environment variables (see \fBgit\fR(1)), and the \fBdiff\fR attribute (see \fBgitattributes\fR(5))\&.
1386 .sp
1387 What the \-p option produces is slightly different from the traditional diff format:
1388 .sp
1389 .RS 4
1390 .ie n \{\
1391 \h'-04' 1.\h'+01'\c
1392 .\}
1393 .el \{\
1394 .sp -1
1395 .IP " 1." 4.2
1396 .\}
1397 It is preceded with a "git diff" header that looks like this:
1398 .sp
1399 .if n \{\
1400 .RS 4
1401 .\}
1402 .nf
1403 diff \-\-git a/file1 b/file2
1404 .fi
1405 .if n \{\
1406 .RE
1407 .\}
1408 .sp
1409 The
1410 \fBa/\fR
1411 and
1412 \fBb/\fR
1413 filenames are the same unless rename/copy is involved\&. Especially, even for a creation or a deletion,
1414 \fB/dev/null\fR
1415 is
1416 \fInot\fR
1417 used in place of the
1418 \fBa/\fR
1419 or
1420 \fBb/\fR
1421 filenames\&.
1422 .sp
1423 When rename/copy is involved,
1424 \fBfile1\fR
1425 and
1426 \fBfile2\fR
1427 show the name of the source file of the rename/copy and the name of the file that rename/copy produces, respectively\&.
1428 .RE
1429 .sp
1430 .RS 4
1431 .ie n \{\
1432 \h'-04' 2.\h'+01'\c
1433 .\}
1434 .el \{\
1435 .sp -1
1436 .IP " 2." 4.2
1437 .\}
1438 It is followed by one or more extended header lines:
1439 .sp
1440 .if n \{\
1441 .RS 4
1442 .\}
1443 .nf
1444 old mode <mode>
1445 new mode <mode>
1446 deleted file mode <mode>
1447 new file mode <mode>
1448 copy from <path>
1449 copy to <path>
1450 rename from <path>
1451 rename to <path>
1452 similarity index <number>
1453 dissimilarity index <number>
1454 index <hash>\&.\&.<hash> <mode>
1455 .fi
1456 .if n \{\
1457 .RE
1458 .\}
1459 .sp
1460 File modes are printed as 6\-digit octal numbers including the file type and file permission bits\&.
1461 .sp
1462 Path names in extended headers do not include the
1463 \fBa/\fR
1464 and
1465 \fBb/\fR
1466 prefixes\&.
1467 .sp
1468 The similarity index is the percentage of unchanged lines, and the dissimilarity index is the percentage of changed lines\&. It is a rounded down integer, followed by a percent sign\&. The similarity index value of 100% is thus reserved for two equal files, while 100% dissimilarity means that no line from the old file made it into the new one\&.
1469 .sp
1470 The index line includes the blob object names before and after the change\&. The <mode> is included if the file mode does not change; otherwise, separate lines indicate the old and the new mode\&.
1471 .RE
1472 .sp
1473 .RS 4
1474 .ie n \{\
1475 \h'-04' 3.\h'+01'\c
1476 .\}
1477 .el \{\
1478 .sp -1
1479 .IP " 3." 4.2
1480 .\}
1481 Pathnames with "unusual" characters are quoted as explained for the configuration variable
1482 \fBcore\&.quotePath\fR
1483 (see
1484 \fBgit-config\fR(1))\&.
1485 .RE
1486 .sp
1487 .RS 4
1488 .ie n \{\
1489 \h'-04' 4.\h'+01'\c
1490 .\}
1491 .el \{\
1492 .sp -1
1493 .IP " 4." 4.2
1494 .\}
1495 All the
1496 \fBfile1\fR
1497 files in the output refer to files before the commit, and all the
1498 \fBfile2\fR
1499 files refer to files after the commit\&. It is incorrect to apply each change to each file sequentially\&. For example, this patch will swap a and b:
1500 .sp
1501 .if n \{\
1502 .RS 4
1503 .\}
1504 .nf
1505 diff \-\-git a/a b/b
1506 rename from a
1507 rename to b
1508 diff \-\-git a/b b/a
1509 rename from b
1510 rename to a
1511 .fi
1512 .if n \{\
1513 .RE
1514 .\}
1515 .RE
1516 .sp
1517 .RS 4
1518 .ie n \{\
1519 \h'-04' 5.\h'+01'\c
1520 .\}
1521 .el \{\
1522 .sp -1
1523 .IP " 5." 4.2
1524 .\}
1525 Hunk headers mention the name of the function to which the hunk applies\&. See "Defining a custom hunk\-header" in
1526 \fBgitattributes\fR(5)
1527 for details of how to tailor to this to specific languages\&.
1528 .RE
1529 .SH "COMBINED DIFF FORMAT"
1530 .sp
1531 Any diff\-generating command can take the \fB\-c\fR or \fB\-\-cc\fR option to produce a \fIcombined diff\fR when showing a merge\&. This is the default format when showing merges with \fBgit-diff\fR(1) or \fBgit-show\fR(1)\&. Note also that you can give suitable \fB\-\-diff\-merges\fR option to any of these commands to force generation of diffs in specific format\&.
1532 .sp
1533 A "combined diff" format looks like this:
1534 .sp
1535 .if n \{\
1536 .RS 4
1537 .\}
1538 .nf
1539 diff \-\-combined describe\&.c
1540 index fabadb8,cc95eb0\&.\&.4866510
1541 \-\-\- a/describe\&.c
1542 +++ b/describe\&.c
1543 @@@ \-98,20 \-98,12 +98,20 @@@
1544 return (a_date > b_date) ? \-1 : (a_date == b_date) ? 0 : 1;
1545 }
1547 \- static void describe(char *arg)
1548 \-static void describe(struct commit *cmit, int last_one)
1549 ++static void describe(char *arg, int last_one)
1550 {
1551 + unsigned char sha1[20];
1552 + struct commit *cmit;
1553 struct commit_list *list;
1554 static int initialized = 0;
1555 struct commit_name *n;
1557 + if (get_sha1(arg, sha1) < 0)
1558 + usage(describe_usage);
1559 + cmit = lookup_commit_reference(sha1);
1560 + if (!cmit)
1561 + usage(describe_usage);
1562 +
1563 if (!initialized) {
1564 initialized = 1;
1565 for_each_ref(get_name);
1566 .fi
1567 .if n \{\
1568 .RE
1569 .\}
1570 .sp
1572 .sp
1573 .RS 4
1574 .ie n \{\
1575 \h'-04' 1.\h'+01'\c
1576 .\}
1577 .el \{\
1578 .sp -1
1579 .IP " 1." 4.2
1580 .\}
1581 It is preceded with a "git diff" header, that looks like this (when the
1582 \fB\-c\fR
1583 option is used):
1584 .sp
1585 .if n \{\
1586 .RS 4
1587 .\}
1588 .nf
1589 diff \-\-combined file
1590 .fi
1591 .if n \{\
1592 .RE
1593 .\}
1594 .sp
1595 or like this (when the
1596 \fB\-\-cc\fR
1597 option is used):
1598 .sp
1599 .if n \{\
1600 .RS 4
1601 .\}
1602 .nf
1603 diff \-\-cc file
1604 .fi
1605 .if n \{\
1606 .RE
1607 .\}
1608 .RE
1609 .sp
1610 .RS 4
1611 .ie n \{\
1612 \h'-04' 2.\h'+01'\c
1613 .\}
1614 .el \{\
1615 .sp -1
1616 .IP " 2." 4.2
1617 .\}
1618 It is followed by one or more extended header lines (this example shows a merge with two parents):
1619 .sp
1620 .if n \{\
1621 .RS 4
1622 .\}
1623 .nf
1624 index <hash>,<hash>\&.\&.<hash>
1625 mode <mode>,<mode>\&.\&.<mode>
1626 new file mode <mode>
1627 deleted file mode <mode>,<mode>
1628 .fi
1629 .if n \{\
1630 .RE
1631 .\}
1632 .sp
1633 The
1634 \fBmode <mode>,<mode>\&.\&.<mode>\fR
1635 line appears only if at least one of the <mode> is different from the rest\&. Extended headers with information about detected contents movement (renames and copying detection) are designed to work with diff of two <tree\-ish> and are not used by combined diff format\&.
1636 .RE
1637 .sp
1638 .RS 4
1639 .ie n \{\
1640 \h'-04' 3.\h'+01'\c
1641 .\}
1642 .el \{\
1643 .sp -1
1644 .IP " 3." 4.2
1645 .\}
1646 It is followed by two\-line from\-file/to\-file header
1647 .sp
1648 .if n \{\
1649 .RS 4
1650 .\}
1651 .nf
1652 \-\-\- a/file
1653 +++ b/file
1654 .fi
1655 .if n \{\
1656 .RE
1657 .\}
1658 .sp
1659 Similar to two\-line header for traditional
1660 \fIunified\fR
1661 diff format,
1662 \fB/dev/null\fR
1663 is used to signal created or deleted files\&.
1664 .sp
1665 However, if the \-\-combined\-all\-paths option is provided, instead of a two\-line from\-file/to\-file you get a N+1 line from\-file/to\-file header, where N is the number of parents in the merge commit
1666 .sp
1667 .if n \{\
1668 .RS 4
1669 .\}
1670 .nf
1671 \-\-\- a/file
1672 \-\-\- a/file
1673 \-\-\- a/file
1674 +++ b/file
1675 .fi
1676 .if n \{\
1677 .RE
1678 .\}
1679 .sp
1680 This extended format can be useful if rename or copy detection is active, to allow you to see the original name of the file in different parents\&.
1681 .RE
1682 .sp
1683 .RS 4
1684 .ie n \{\
1685 \h'-04' 4.\h'+01'\c
1686 .\}
1687 .el \{\
1688 .sp -1
1689 .IP " 4." 4.2
1690 .\}
1691 Chunk header format is modified to prevent people from accidentally feeding it to
1692 \fBpatch \-p1\fR\&. Combined diff format was created for review of merge commit changes, and was not meant to be applied\&. The change is similar to the change in the extended
1693 \fIindex\fR
1694 header:
1695 .sp
1696 .if n \{\
1697 .RS 4
1698 .\}
1699 .nf
1700 @@@ <from\-file\-range> <from\-file\-range> <to\-file\-range> @@@
1701 .fi
1702 .if n \{\
1703 .RE
1704 .\}
1705 .sp
1706 There are (number of parents + 1)
1707 \fB@\fR
1708 characters in the chunk header for combined diff format\&.
1709 .RE
1710 .sp
1711 Unlike the traditional \fIunified\fR diff format, which shows two files A and B with a single column that has \fB\-\fR (minus \(em appears in A but removed in B), \fB+\fR (plus \(em missing in A but added to B), or \fB" "\fR (space \(em unchanged) prefix, this format compares two or more files file1, file2,\&... with one file X, and shows how X differs from each of fileN\&. One column for each of fileN is prepended to the output line to note how X\(cqs line is different from it\&.
1712 .sp
1713 A \fB\-\fR character in the column N means that the line appears in fileN but it does not appear in the result\&. A \fB+\fR character in the column N means that the line appears in the result, and fileN does not have that line (in other words, the line was added, from the point of view of that parent)\&.
1714 .sp
1715 In the above example output, the function signature was changed from both files (hence two \fB\-\fR removals from both file1 and file2, plus \fB++\fR to mean one line that was added does not appear in either file1 or file2)\&. Also eight other lines are the same from file1 but do not appear in file2 (hence prefixed with \fB+\fR)\&.
1716 .sp
1717 When shown by \fBgit diff\-tree \-c\fR, it compares the parents of a merge commit with the merge result (i\&.e\&. file1\&.\&.fileN are the parents)\&. When shown by \fBgit diff\-files \-c\fR, it compares the two unresolved merge parents with the working tree file (i\&.e\&. file1 is stage 2 aka "our version", file2 is stage 3 aka "their version")\&.
1718 .SH "OTHER DIFF FORMATS"
1719 .sp
1720 The \fB\-\-summary\fR option describes newly added, deleted, renamed and copied files\&. The \fB\-\-stat\fR option adds diffstat(1) graph to the output\&. These options can be combined with other options, such as \fB\-p\fR, and are meant for human consumption\&.
1721 .sp
1722 When showing a change that involves a rename or a copy, \fB\-\-stat\fR output formats the pathnames compactly by combining common prefix and suffix of the pathnames\&. For example, a change that moves \fBarch/i386/Makefile\fR to \fBarch/x86/Makefile\fR while modifying 4 lines will be shown like this:
1723 .sp
1724 .if n \{\
1725 .RS 4
1726 .\}
1727 .nf
1728 arch/{i386 => x86}/Makefile | 4 +\-\-
1729 .fi
1730 .if n \{\
1731 .RE
1732 .\}
1733 .sp
1734 .sp
1735 The \fB\-\-numstat\fR option gives the diffstat(1) information but is designed for easier machine consumption\&. An entry in \fB\-\-numstat\fR output looks like this:
1736 .sp
1737 .if n \{\
1738 .RS 4
1739 .\}
1740 .nf
1741 1 2 README
1742 3 1 arch/{i386 => x86}/Makefile
1743 .fi
1744 .if n \{\
1745 .RE
1746 .\}
1747 .sp
1748 .sp
1749 That is, from left to right:
1750 .sp
1751 .RS 4
1752 .ie n \{\
1753 \h'-04' 1.\h'+01'\c
1754 .\}
1755 .el \{\
1756 .sp -1
1757 .IP " 1." 4.2
1758 .\}
1759 the number of added lines;
1760 .RE
1761 .sp
1762 .RS 4
1763 .ie n \{\
1764 \h'-04' 2.\h'+01'\c
1765 .\}
1766 .el \{\
1767 .sp -1
1768 .IP " 2." 4.2
1769 .\}
1770 a tab;
1771 .RE
1772 .sp
1773 .RS 4
1774 .ie n \{\
1775 \h'-04' 3.\h'+01'\c
1776 .\}
1777 .el \{\
1778 .sp -1
1779 .IP " 3." 4.2
1780 .\}
1781 the number of deleted lines;
1782 .RE
1783 .sp
1784 .RS 4
1785 .ie n \{\
1786 \h'-04' 4.\h'+01'\c
1787 .\}
1788 .el \{\
1789 .sp -1
1790 .IP " 4." 4.2
1791 .\}
1792 a tab;
1793 .RE
1794 .sp
1795 .RS 4
1796 .ie n \{\
1797 \h'-04' 5.\h'+01'\c
1798 .\}
1799 .el \{\
1800 .sp -1
1801 .IP " 5." 4.2
1802 .\}
1803 pathname (possibly with rename/copy information);
1804 .RE
1805 .sp
1806 .RS 4
1807 .ie n \{\
1808 \h'-04' 6.\h'+01'\c
1809 .\}
1810 .el \{\
1811 .sp -1
1812 .IP " 6." 4.2
1813 .\}
1814 a newline\&.
1815 .RE
1816 .sp
1817 When \fB\-z\fR output option is in effect, the output is formatted this way:
1818 .sp
1819 .if n \{\
1820 .RS 4
1821 .\}
1822 .nf
1823 1 2 README NUL
1824 3 1 NUL arch/i386/Makefile NUL arch/x86/Makefile NUL
1825 .fi
1826 .if n \{\
1827 .RE
1828 .\}
1829 .sp
1830 .sp
1831 That is:
1832 .sp
1833 .RS 4
1834 .ie n \{\
1835 \h'-04' 1.\h'+01'\c
1836 .\}
1837 .el \{\
1838 .sp -1
1839 .IP " 1." 4.2
1840 .\}
1841 the number of added lines;
1842 .RE
1843 .sp
1844 .RS 4
1845 .ie n \{\
1846 \h'-04' 2.\h'+01'\c
1847 .\}
1848 .el \{\
1849 .sp -1
1850 .IP " 2." 4.2
1851 .\}
1852 a tab;
1853 .RE
1854 .sp
1855 .RS 4
1856 .ie n \{\
1857 \h'-04' 3.\h'+01'\c
1858 .\}
1859 .el \{\
1860 .sp -1
1861 .IP " 3." 4.2
1862 .\}
1863 the number of deleted lines;
1864 .RE
1865 .sp
1866 .RS 4
1867 .ie n \{\
1868 \h'-04' 4.\h'+01'\c
1869 .\}
1870 .el \{\
1871 .sp -1
1872 .IP " 4." 4.2
1873 .\}
1874 a tab;
1875 .RE
1876 .sp
1877 .RS 4
1878 .ie n \{\
1879 \h'-04' 5.\h'+01'\c
1880 .\}
1881 .el \{\
1882 .sp -1
1883 .IP " 5." 4.2
1884 .\}
1885 a NUL (only exists if renamed/copied);
1886 .RE
1887 .sp
1888 .RS 4
1889 .ie n \{\
1890 \h'-04' 6.\h'+01'\c
1891 .\}
1892 .el \{\
1893 .sp -1
1894 .IP " 6." 4.2
1895 .\}
1896 pathname in preimage;
1897 .RE
1898 .sp
1899 .RS 4
1900 .ie n \{\
1901 \h'-04' 7.\h'+01'\c
1902 .\}
1903 .el \{\
1904 .sp -1
1905 .IP " 7." 4.2
1906 .\}
1907 a NUL (only exists if renamed/copied);
1908 .RE
1909 .sp
1910 .RS 4
1911 .ie n \{\
1912 \h'-04' 8.\h'+01'\c
1913 .\}
1914 .el \{\
1915 .sp -1
1916 .IP " 8." 4.2
1917 .\}
1918 pathname in postimage (only exists if renamed/copied);
1919 .RE
1920 .sp
1921 .RS 4
1922 .ie n \{\
1923 \h'-04' 9.\h'+01'\c
1924 .\}
1925 .el \{\
1926 .sp -1
1927 .IP " 9." 4.2
1928 .\}
1929 a NUL\&.
1930 .RE
1931 .sp
1932 The extra \fBNUL\fR before the preimage path in renamed case is to allow scripts that read the output to tell if the current record being read is a single\-path record or a rename/copy record without reading ahead\&. After reading added and deleted lines, reading up to \fBNUL\fR would yield the pathname, but if that is \fBNUL\fR, the record will show two paths\&.
1933 .SH "OPERATING MODES"
1934 .sp
1935 You can choose whether you want to trust the index file entirely (using the \fB\-\-cached\fR flag) or ask the diff logic to show any files that don\(cqt match the stat state as being "tentatively changed"\&. Both of these operations are very useful indeed\&.
1936 .SH "CACHED MODE"
1937 .sp
1938 If \fB\-\-cached\fR is specified, it allows you to ask:
1939 .sp
1940 .if n \{\
1941 .RS 4
1942 .\}
1943 .nf
1944 show me the differences between HEAD and the current index
1945 contents (the ones I\*(Aqd write using \*(Aqgit write\-tree\*(Aq)
1946 .fi
1947 .if n \{\
1948 .RE
1949 .\}
1950 .sp
1951 For example, let\(cqs say that you have worked on your working directory, updated some files in the index and are ready to commit\&. You want to see exactly \fBwhat\fR you are going to commit, without having to write a new tree object and compare it that way, and to do that, you just do
1952 .sp
1953 .if n \{\
1954 .RS 4
1955 .\}
1956 .nf
1957 git diff\-index \-\-cached HEAD
1958 .fi
1959 .if n \{\
1960 .RE
1961 .\}
1962 .sp
1963 Example: let\(cqs say I had renamed \fBcommit\&.c\fR to \fBgit\-commit\&.c\fR, and I had done an \fBupdate\-index\fR to make that effective in the index file\&. \fBgit diff\-files\fR wouldn\(cqt show anything at all, since the index file matches my working directory\&. But doing a \fIgit diff\-index\fR does:
1964 .sp
1965 .if n \{\
1966 .RS 4
1967 .\}
1968 .nf
1969 torvalds@ppc970:~/git> git diff\-index \-\-cached HEAD
1970 :100644 000000 4161aecc6700a2eb579e842af0b7f22b98443f74 0000000000000000000000000000000000000000 D commit\&.c
1971 :000000 100644 0000000000000000000000000000000000000000 4161aecc6700a2eb579e842af0b7f22b98443f74 A git\-commit\&.c
1972 .fi
1973 .if n \{\
1974 .RE
1975 .\}
1976 .sp
1977 You can see easily that the above is a rename\&.
1978 .sp
1979 In fact, \fBgit diff\-index \-\-cached\fR \fBshould\fR always be entirely equivalent to actually doing a \fIgit write\-tree\fR and comparing that\&. Except this one is much nicer for the case where you just want to check where you are\&.
1980 .sp
1981 So doing a \fBgit diff\-index \-\-cached\fR is basically very useful when you are asking yourself "what have I already marked for being committed, and what\(cqs the difference to a previous tree"\&.
1982 .SH "NON\-CACHED MODE"
1983 .sp
1984 The "non\-cached" mode takes a different approach, and is potentially the more useful of the two in that what it does can\(cqt be emulated with a \fIgit write\-tree\fR + \fIgit diff\-tree\fR\&. Thus that\(cqs the default mode\&. The non\-cached version asks the question:
1985 .sp
1986 .if n \{\
1987 .RS 4
1988 .\}
1989 .nf
1990 show me the differences between HEAD and the currently checked out
1991 tree \- index contents _and_ files that aren\*(Aqt up to date
1992 .fi
1993 .if n \{\
1994 .RE
1995 .\}
1996 .sp
1997 which is obviously a very useful question too, since that tells you what you \fBcould\fR commit\&. Again, the output matches the \fIgit diff\-tree \-r\fR output to a tee, but with a twist\&.
1998 .sp
1999 The twist is that if some file doesn\(cqt match the index, we don\(cqt have a backing store thing for it, and we use the magic "all\-zero" sha1 to show that\&. So let\(cqs say that you have edited \fBkernel/sched\&.c\fR, but have not actually done a \fIgit update\-index\fR on it yet \- there is no "object" associated with the new state, and you get:
2000 .sp
2001 .if n \{\
2002 .RS 4
2003 .\}
2004 .nf
2005 torvalds@ppc970:~/v2\&.6/linux> git diff\-index \-\-abbrev HEAD
2006 :100644 100644 7476bb5ba 000000000 M kernel/sched\&.c
2007 .fi
2008 .if n \{\
2009 .RE
2010 .\}
2011 .sp
2012 i\&.e\&., it shows that the tree has changed, and that \fBkernel/sched\&.c\fR is not up to date and may contain new stuff\&. The all\-zero sha1 means that to get the real diff, you need to look at the object in the working directory directly rather than do an object\-to\-object diff\&.
2013 .if n \{\
2014 .sp
2015 .\}
2016 .RS 4
2017 .it 1 an-trap
2018 .nr an-no-space-flag 1
2019 .nr an-break-flag 1
2020 .br
2021 .ps +1
2022 \fBNote\fR
2023 .ps -1
2024 .br
2025 .sp
2026 As with other commands of this type, \fIgit diff\-index\fR does not actually look at the contents of the file at all\&. So maybe \fBkernel/sched\&.c\fR hasn\(cqt actually changed, and it\(cqs just that you touched it\&. In either case, it\(cqs a note that you need to \fIgit update\-index\fR it to make the index be in sync\&.
2027 .sp .5v
2028 .RE
2029 .if n \{\
2030 .sp
2031 .\}
2032 .RS 4
2033 .it 1 an-trap
2034 .nr an-no-space-flag 1
2035 .nr an-break-flag 1
2036 .br
2037 .ps +1
2038 \fBNote\fR
2039 .ps -1
2040 .br
2041 .sp
2042 You can have a mixture of files show up as "has been updated" and "is still dirty in the working directory" together\&. You can always tell which file is in which state, since the "has been updated" ones show a valid sha1, and the "not in sync with the index" ones will always have the special all\-zero sha1\&.
2043 .sp .5v
2044 .RE
2045 .SH "GIT"
2046 .sp
2047 Part of the \fBgit\fR(1) suite