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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: 10/27/2022
6 .\" Manual: Git Manual
7 .\" Source: Git 2.38.1.220.g9388e93f00
8 .\" Language: English
9 .\"
10 .TH "GIT\-DIFF\-INDEX" "1" "10/27/2022" "Git 2\&.38\&.1\&.220\&.g9388e9" "Git Manual"
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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 on generating patches)\&.
46 .RE
47 .PP
48 \-s, \-\-no\-patch
49 .RS 4
50 Suppress diff output\&. Useful for commands like
51 \fBgit show\fR
52 that show the patch by default, or to cancel the effect of
53 \fB\-\-patch\fR\&.
54 .RE
55 .PP
56 \-U<n>, \-\-unified=<n>
57 .RS 4
58 Generate diffs with <n> lines of context instead of the usual three\&. Implies
59 \fB\-\-patch\fR\&.
60 .RE
61 .PP
62 \-\-output=<file>
63 .RS 4
64 Output to a specific file instead of stdout\&.
65 .RE
66 .PP
67 \-\-output\-indicator\-new=<char>, \-\-output\-indicator\-old=<char>, \-\-output\-indicator\-context=<char>
68 .RS 4
69 Specify the character used to indicate new, old or context lines in the generated patch\&. Normally they are
70 \fI+\fR,
71 \fI\-\fR
72 and \(aq \(aq respectively\&.
73 .RE
74 .PP
75 \-\-raw
76 .RS 4
77 Generate the diff in raw format\&. This is the default\&.
78 .RE
79 .PP
80 \-\-patch\-with\-raw
81 .RS 4
82 Synonym for
83 \fB\-p \-\-raw\fR\&.
84 .RE
85 .PP
86 \-\-indent\-heuristic
87 .RS 4
88 Enable the heuristic that shifts diff hunk boundaries to make patches easier to read\&. This is the default\&.
89 .RE
90 .PP
91 \-\-no\-indent\-heuristic
92 .RS 4
93 Disable the indent heuristic\&.
94 .RE
95 .PP
96 \-\-minimal
97 .RS 4
98 Spend extra time to make sure the smallest possible diff is produced\&.
99 .RE
100 .PP
101 \-\-patience
102 .RS 4
103 Generate a diff using the "patience diff" algorithm\&.
104 .RE
105 .PP
106 \-\-histogram
107 .RS 4
108 Generate a diff using the "histogram diff" algorithm\&.
109 .RE
110 .PP
111 \-\-anchored=<text>
112 .RS 4
113 Generate a diff using the "anchored diff" algorithm\&.
114 .sp
115 This option may be specified more than once\&.
116 .sp
117 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\&.
118 .RE
119 .PP
120 \-\-diff\-algorithm={patience|minimal|histogram|myers}
121 .RS 4
122 Choose a diff algorithm\&. The variants are as follows:
123 .PP
124 \fBdefault\fR, \fBmyers\fR
125 .RS 4
126 The basic greedy diff algorithm\&. Currently, this is the default\&.
127 .RE
128 .PP
129 \fBminimal\fR
130 .RS 4
131 Spend extra time to make sure the smallest possible diff is produced\&.
132 .RE
133 .PP
134 \fBpatience\fR
135 .RS 4
136 Use "patience diff" algorithm when generating patches\&.
137 .RE
138 .PP
139 \fBhistogram\fR
140 .RS 4
141 This algorithm extends the patience algorithm to "support low\-occurrence common elements"\&.
142 .RE
143 .sp
144 For instance, if you configured the
145 \fBdiff\&.algorithm\fR
146 variable to a non\-default value and want to use the default one, then you have to use
147 \fB\-\-diff\-algorithm=default\fR
148 option\&.
149 .RE
150 .PP
151 \-\-stat[=<width>[,<name\-width>[,<count>]]]
152 .RS 4
153 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
154 \fB<width>\fR\&. The width of the filename part can be limited by giving another width
155 \fB<name\-width>\fR
156 after a comma\&. The width of the graph part can be limited by using
157 \fB\-\-stat\-graph\-width=<width>\fR
158 (affects all commands generating a stat graph) or by setting
159 \fBdiff\&.statGraphWidth=<width>\fR
160 (does not affect
161 \fBgit format\-patch\fR)\&. By giving a third parameter
162 \fB<count>\fR, you can limit the output to the first
163 \fB<count>\fR
164 lines, followed by
165 \fB\&.\&.\&.\fR
166 if there are more\&.
167 .sp
168 These parameters can also be set individually with
169 \fB\-\-stat\-width=<width>\fR,
170 \fB\-\-stat\-name\-width=<name\-width>\fR
171 and
172 \fB\-\-stat\-count=<count>\fR\&.
173 .RE
174 .PP
175 \-\-compact\-summary
176 .RS 4
177 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
178 \fB\-\-stat\fR\&.
179 .RE
180 .PP
181 \-\-numstat
182 .RS 4
183 Similar to
184 \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
185 \fB\-\fR
186 instead of saying
187 \fB0 0\fR\&.
188 .RE
189 .PP
190 \-\-shortstat
191 .RS 4
192 Output only the last line of the
193 \fB\-\-stat\fR
194 format containing total number of modified files, as well as number of added and deleted lines\&.
195 .RE
196 .PP
197 \-X[<param1,param2,\&...>], \-\-dirstat[=<param1,param2,\&...>]
198 .RS 4
199 Output the distribution of relative amount of changes for each sub\-directory\&. The behavior of
200 \fB\-\-dirstat\fR
201 can be customized by passing it a comma separated list of parameters\&. The defaults are controlled by the
202 \fBdiff\&.dirstat\fR
203 configuration variable (see
204 \fBgit-config\fR(1))\&. The following parameters are available:
205 .PP
206 \fBchanges\fR
207 .RS 4
208 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\&.
209 .RE
210 .PP
211 \fBlines\fR
212 .RS 4
213 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
214 \fB\-\-dirstat\fR
215 behavior than the
216 \fBchanges\fR
217 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
218 \fB\-\-*stat\fR
219 options\&.
220 .RE
221 .PP
222 \fBfiles\fR
223 .RS 4
224 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
225 \fB\-\-dirstat\fR
226 behavior, since it does not have to look at the file contents at all\&.
227 .RE
228 .PP
229 \fBcumulative\fR
230 .RS 4
231 Count changes in a child directory for the parent directory as well\&. Note that when using
232 \fBcumulative\fR, the sum of the percentages reported may exceed 100%\&. The default (non\-cumulative) behavior can be specified with the
233 \fBnoncumulative\fR
234 parameter\&.
235 .RE
236 .PP
237 <limit>
238 .RS 4
239 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\&.
240 .RE
241 .sp
242 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:
243 \fB\-\-dirstat=files,10,cumulative\fR\&.
244 .RE
245 .PP
246 \-\-cumulative
247 .RS 4
248 Synonym for \-\-dirstat=cumulative
249 .RE
250 .PP
251 \-\-dirstat\-by\-file[=<param1,param2>\&...]
252 .RS 4
253 Synonym for \-\-dirstat=files,param1,param2\&...
254 .RE
255 .PP
256 \-\-summary
257 .RS 4
258 Output a condensed summary of extended header information such as creations, renames and mode changes\&.
259 .RE
260 .PP
261 \-\-patch\-with\-stat
262 .RS 4
263 Synonym for
264 \fB\-p \-\-stat\fR\&.
265 .RE
266 .PP
267 \-z
268 .RS 4
269 When
270 \fB\-\-raw\fR,
271 \fB\-\-numstat\fR,
272 \fB\-\-name\-only\fR
273 or
274 \fB\-\-name\-status\fR
275 has been given, do not munge pathnames and use NULs as output field terminators\&.
276 .sp
277 Without this option, pathnames with "unusual" characters are quoted as explained for the configuration variable
278 \fBcore\&.quotePath\fR
279 (see
280 \fBgit-config\fR(1))\&.
281 .RE
282 .PP
283 \-\-name\-only
284 .RS 4
285 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
286 \fBgit-log\fR(1)
287 manual page\&.
288 .RE
289 .PP
290 \-\-name\-status
291 .RS 4
292 Show only names and status of changed files\&. See the description of the
293 \fB\-\-diff\-filter\fR
294 option on what the status letters mean\&. Just like
295 \fB\-\-name\-only\fR
296 the file names are often encoded in UTF\-8\&.
297 .RE
298 .PP
299 \-\-submodule[=<format>]
300 .RS 4
301 Specify how differences in submodules are shown\&. When specifying
302 \fB\-\-submodule=short\fR
303 the
304 \fIshort\fR
305 format is used\&. This format just shows the names of the commits at the beginning and end of the range\&. When
306 \fB\-\-submodule\fR
307 or
308 \fB\-\-submodule=log\fR
309 is specified, the
310 \fIlog\fR
311 format is used\&. This format lists the commits in the range like
312 \fBgit-submodule\fR(1)
313 \fBsummary\fR
314 does\&. When
315 \fB\-\-submodule=diff\fR
316 is specified, the
317 \fIdiff\fR
318 format is used\&. This format shows an inline diff of the changes in the submodule contents between the commit range\&. Defaults to
319 \fBdiff\&.submodule\fR
320 or the
321 \fIshort\fR
322 format if the config option is unset\&.
323 .RE
324 .PP
325 \-\-color[=<when>]
326 .RS 4
327 Show colored diff\&.
328 \fB\-\-color\fR
329 (i\&.e\&. without
330 \fI=<when>\fR) is the same as
331 \fB\-\-color=always\fR\&.
332 \fI<when>\fR
333 can be one of
334 \fBalways\fR,
335 \fBnever\fR, or
336 \fBauto\fR\&.
337 .RE
338 .PP
339 \-\-no\-color
340 .RS 4
341 Turn off colored diff\&. It is the same as
342 \fB\-\-color=never\fR\&.
343 .RE
344 .PP
345 \-\-color\-moved[=<mode>]
346 .RS 4
347 Moved lines of code are colored differently\&. The <mode> defaults to
348 \fIno\fR
349 if the option is not given and to
350 \fIzebra\fR
351 if the option with no mode is given\&. The mode must be one of:
352 .PP
353 no
354 .RS 4
355 Moved lines are not highlighted\&.
356 .RE
357 .PP
358 default
359 .RS 4
360 Is a synonym for
361 \fBzebra\fR\&. This may change to a more sensible mode in the future\&.
362 .RE
363 .PP
364 plain
365 .RS 4
366 Any line that is added in one location and was removed in another location will be colored with
367 \fIcolor\&.diff\&.newMoved\fR\&. Similarly
368 \fIcolor\&.diff\&.oldMoved\fR
369 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\&.
370 .RE
371 .PP
372 blocks
373 .RS 4
374 Blocks of moved text of at least 20 alphanumeric characters are detected greedily\&. The detected blocks are painted using either the
375 \fIcolor\&.diff\&.{old,new}Moved\fR
376 color\&. Adjacent blocks cannot be told apart\&.
377 .RE
378 .PP
379 zebra
380 .RS 4
381 Blocks of moved text are detected as in
382 \fIblocks\fR
383 mode\&. The blocks are painted using either the
384 \fIcolor\&.diff\&.{old,new}Moved\fR
385 color or
386 \fIcolor\&.diff\&.{old,new}MovedAlternative\fR\&. The change between the two colors indicates that a new block was detected\&.
387 .RE
388 .PP
389 dimmed\-zebra
390 .RS 4
391 Similar to
392 \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\&.
393 \fBdimmed_zebra\fR
394 is a deprecated synonym\&.
395 .RE
396 .RE
397 .PP
398 \-\-no\-color\-moved
399 .RS 4
400 Turn off move detection\&. This can be used to override configuration settings\&. It is the same as
401 \fB\-\-color\-moved=no\fR\&.
402 .RE
403 .PP
404 \-\-color\-moved\-ws=<modes>
405 .RS 4
406 This configures how whitespace is ignored when performing the move detection for
407 \fB\-\-color\-moved\fR\&. These modes can be given as a comma separated list:
408 .PP
409 no
410 .RS 4
411 Do not ignore whitespace when performing move detection\&.
412 .RE
413 .PP
414 ignore\-space\-at\-eol
415 .RS 4
416 Ignore changes in whitespace at EOL\&.
417 .RE
418 .PP
419 ignore\-space\-change
420 .RS 4
421 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\&.
422 .RE
423 .PP
424 ignore\-all\-space
425 .RS 4
426 Ignore whitespace when comparing lines\&. This ignores differences even if one line has whitespace where the other line has none\&.
427 .RE
428 .PP
429 allow\-indentation\-change
430 .RS 4
431 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\&.
432 .RE
433 .RE
434 .PP
435 \-\-no\-color\-moved\-ws
436 .RS 4
437 Do not ignore whitespace when performing move detection\&. This can be used to override configuration settings\&. It is the same as
438 \fB\-\-color\-moved\-ws=no\fR\&.
439 .RE
440 .PP
441 \-\-word\-diff[=<mode>]
442 .RS 4
443 Show a word diff, using the <mode> to delimit changed words\&. By default, words are delimited by whitespace; see
444 \fB\-\-word\-diff\-regex\fR
445 below\&. The <mode> defaults to
446 \fIplain\fR, and must be one of:
447 .PP
448 color
449 .RS 4
450 Highlight changed words using only colors\&. Implies
451 \fB\-\-color\fR\&.
452 .RE
453 .PP
454 plain
455 .RS 4
456 Show words as
457 \fB[\-removed\-]\fR
458 and
459 \fB{+added+}\fR\&. Makes no attempts to escape the delimiters if they appear in the input, so the output may be ambiguous\&.
460 .RE
461 .PP
462 porcelain
463 .RS 4
464 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
465 \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
466 \fB~\fR
467 on a line of its own\&.
468 .RE
469 .PP
470 none
471 .RS 4
472 Disable word diff again\&.
473 .RE
474 .sp
475 Note that despite the name of the first mode, color is used to highlight the changed parts in all modes if enabled\&.
476 .RE
477 .PP
478 \-\-word\-diff\-regex=<regex>
479 .RS 4
480 Use <regex> to decide what a word is, instead of considering runs of non\-whitespace to be a word\&. Also implies
481 \fB\-\-word\-diff\fR
482 unless it was already enabled\&.
483 .sp
484 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
485 \fB|[^[:space:]]\fR
486 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\&.
487 .sp
488 For example,
489 \fB\-\-word\-diff\-regex=\&.\fR
490 will treat each character as a word and, correspondingly, show differences character by character\&.
491 .sp
492 The regex can also be set via a diff driver or configuration option, see
493 \fBgitattributes\fR(5)
494 or
495 \fBgit-config\fR(1)\&. Giving it explicitly overrides any diff driver or configuration setting\&. Diff drivers override configuration settings\&.
496 .RE
497 .PP
498 \-\-color\-words[=<regex>]
499 .RS 4
500 Equivalent to
501 \fB\-\-word\-diff=color\fR
502 plus (if a regex was specified)
503 \fB\-\-word\-diff\-regex=<regex>\fR\&.
504 .RE
505 .PP
506 \-\-no\-renames
507 .RS 4
508 Turn off rename detection, even when the configuration file gives the default to do so\&.
509 .RE
510 .PP
511 \-\-[no\-]rename\-empty
512 .RS 4
513 Whether to use empty blobs as rename source\&.
514 .RE
515 .PP
516 \-\-check
517 .RS 4
518 Warn if changes introduce conflict markers or whitespace errors\&. What are considered whitespace errors is controlled by
519 \fBcore\&.whitespace\fR
520 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\&.
521 .RE
522 .PP
523 \-\-ws\-error\-highlight=<kind>
524 .RS 4
525 Highlight whitespace errors in the
526 \fBcontext\fR,
527 \fBold\fR
528 or
529 \fBnew\fR
530 lines of the diff\&. Multiple values are separated by comma,
531 \fBnone\fR
532 resets previous values,
533 \fBdefault\fR
534 reset the list to
535 \fBnew\fR
536 and
537 \fBall\fR
538 is a shorthand for
539 \fBold,new,context\fR\&. When this option is not given, and the configuration variable
540 \fBdiff\&.wsErrorHighlight\fR
541 is not set, only whitespace errors in
542 \fBnew\fR
543 lines are highlighted\&. The whitespace errors are colored with
544 \fBcolor\&.diff\&.whitespace\fR\&.
545 .RE
546 .PP
547 \-\-full\-index
548 .RS 4
549 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\&.
550 .RE
551 .PP
552 \-\-binary
553 .RS 4
554 In addition to
555 \fB\-\-full\-index\fR, output a binary diff that can be applied with
556 \fBgit\-apply\fR\&. Implies
557 \fB\-\-patch\fR\&.
558 .RE
559 .PP
560 \-\-abbrev[=<n>]
561 .RS 4
562 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
563 \fI<n>\fR
564 hexdigits long that uniquely refers the object\&. In diff\-patch output format,
565 \fB\-\-full\-index\fR
566 takes higher precedence, i\&.e\&. if
567 \fB\-\-full\-index\fR
568 is specified, full blob names will be shown regardless of
569 \fB\-\-abbrev\fR\&. Non default number of digits can be specified with
570 \fB\-\-abbrev=<n>\fR\&.
571 .RE
572 .PP
573 \-B[<n>][/<m>], \-\-break\-rewrites[=[<n>][/<m>]]
574 .RS 4
575 Break complete rewrite changes into pairs of delete and create\&. This serves two purposes:
576 .sp
577 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
578 \fBm\fR
579 controls this aspect of the \-B option (defaults to 60%)\&.
580 \fB\-B/70%\fR
581 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)\&.
582 .sp
583 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
584 \fBn\fR
585 controls this aspect of the \-B option (defaults to 50%)\&.
586 \fB\-B20%\fR
587 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\&.
588 .RE
589 .PP
590 \-M[<n>], \-\-find\-renames[=<n>]
591 .RS 4
592 Detect renames\&. If
593 \fBn\fR
594 is specified, it is a threshold on the similarity index (i\&.e\&. amount of addition/deletions compared to the file\(cqs size)\&. For example,
595 \fB\-M90%\fR
596 means Git should consider a delete/add pair to be a rename if more than 90% of the file hasn\(cqt changed\&. Without a
597 \fB%\fR
598 sign, the number is to be read as a fraction, with a decimal point before it\&. I\&.e\&.,
599 \fB\-M5\fR
600 becomes 0\&.5, and is thus the same as
601 \fB\-M50%\fR\&. Similarly,
602 \fB\-M05\fR
603 is the same as
604 \fB\-M5%\fR\&. To limit detection to exact renames, use
605 \fB\-M100%\fR\&. The default similarity index is 50%\&.
606 .RE
607 .PP
608 \-C[<n>], \-\-find\-copies[=<n>]
609 .RS 4
610 Detect copies as well as renames\&. See also
611 \fB\-\-find\-copies\-harder\fR\&. If
612 \fBn\fR
613 is specified, it has the same meaning as for
614 \fB\-M<n>\fR\&.
615 .RE
616 .PP
617 \-\-find\-copies\-harder
618 .RS 4
619 For performance reasons, by default,
620 \fB\-C\fR
621 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
622 \fB\-C\fR
623 option has the same effect\&.
624 .RE
625 .PP
626 \-D, \-\-irreversible\-delete
627 .RS 4
628 Omit the preimage for deletes, i\&.e\&. print only the header but not the diff between the preimage and
629 \fB/dev/null\fR\&. The resulting patch is not meant to be applied with
630 \fBpatch\fR
631 or
632 \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\&.
633 .sp
634 When used together with
635 \fB\-B\fR, omit also the preimage in the deletion part of a delete/create pair\&.
636 .RE
637 .PP
638 \-l<num>
639 .RS 4
640 The
641 \fB\-M\fR
642 and
643 \fB\-C\fR
644 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\&.
645 .RE
646 .PP
647 \-\-diff\-filter=[(A|C|D|M|R|T|U|X|B)\&...[*]]
648 .RS 4
649 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
650 \fB*\fR
651 (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\&.
652 .sp
653 Also, these upper\-case letters can be downcased to exclude\&. E\&.g\&.
654 \fB\-\-diff\-filter=ad\fR
655 excludes added and deleted paths\&.
656 .sp
657 Note that not all diffs can feature all types\&. For instance, copied and renamed entries cannot appear if detection for those types is disabled\&.
658 .RE
659 .PP
660 \-S<string>
661 .RS 4
662 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\&.
663 .sp
664 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
665 \fB\-S\fR, and keep going until you get the very first version of the block\&.
666 .sp
667 Binary files are searched as well\&.
668 .RE
669 .PP
670 \-G<regex>
671 .RS 4
672 Look for differences whose patch text contains added/removed lines that match <regex>\&.
673 .sp
674 To illustrate the difference between
675 \fB\-S<regex> \-\-pickaxe\-regex\fR
676 and
677 \fB\-G<regex>\fR, consider a commit with the following diff in the same file:
678 .sp
679 .if n \{\
680 .RS 4
681 .\}
682 .nf
683 + return frotz(nitfol, two\->ptr, 1, 0);
684 \&.\&.\&.
685 \- hit = frotz(nitfol, mf2\&.ptr, 1, 0);
686 .fi
687 .if n \{\
688 .RE
689 .\}
690 .sp
691 While
692 \fBgit log \-G"frotz\e(nitfol"\fR
693 will show this commit,
694 \fBgit log \-S"frotz\e(nitfol" \-\-pickaxe\-regex\fR
695 will not (because the number of occurrences of that string did not change)\&.
696 .sp
697 Unless
698 \fB\-\-text\fR
699 is supplied patches of binary files without a textconv filter will be ignored\&.
700 .sp
701 See the
702 \fIpickaxe\fR
703 entry in
704 \fBgitdiffcore\fR(7)
705 for more information\&.
706 .RE
707 .PP
708 \-\-find\-object=<object\-id>
709 .RS 4
710 Look for differences that change the number of occurrences of the specified object\&. Similar to
711 \fB\-S\fR, just the argument is different in that it doesn\(cqt search for a specific string but for a specific object id\&.
712 .sp
713 The object can be a blob or a submodule commit\&. It implies the
714 \fB\-t\fR
715 option in
716 \fBgit\-log\fR
717 to also find trees\&.
718 .RE
719 .PP
720 \-\-pickaxe\-all
721 .RS 4
722 When
723 \fB\-S\fR
724 or
725 \fB\-G\fR
726 finds a change, show all the changes in that changeset, not just the files that contain the change in <string>\&.
727 .RE
728 .PP
729 \-\-pickaxe\-regex
730 .RS 4
731 Treat the <string> given to
732 \fB\-S\fR
733 as an extended POSIX regular expression to match\&.
734 .RE
735 .PP
736 \-O<orderfile>
737 .RS 4
738 Control the order in which files appear in the output\&. This overrides the
739 \fBdiff\&.orderFile\fR
740 configuration variable (see
741 \fBgit-config\fR(1))\&. To cancel
742 \fBdiff\&.orderFile\fR, use
743 \fB\-O/dev/null\fR\&.
744 .sp
745 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\&.
746 .sp
747 <orderfile> is parsed as follows:
748 .sp
749 .RS 4
750 .ie n \{\
751 \h'-04'\(bu\h'+03'\c
752 .\}
753 .el \{\
754 .sp -1
755 .IP \(bu 2.3
756 .\}
757 Blank lines are ignored, so they can be used as separators for readability\&.
758 .RE
759 .sp
760 .RS 4
761 .ie n \{\
762 \h'-04'\(bu\h'+03'\c
763 .\}
764 .el \{\
765 .sp -1
766 .IP \(bu 2.3
767 .\}
768 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\&.
769 .RE
770 .sp
771 .RS 4
772 .ie n \{\
773 \h'-04'\(bu\h'+03'\c
774 .\}
775 .el \{\
776 .sp -1
777 .IP \(bu 2.3
778 .\}
779 Each other line contains a single pattern\&.
780 .RE
781 .sp
782 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"\&.
783 .RE
784 .PP
785 \-\-skip\-to=<file>, \-\-rotate\-to=<file>
786 .RS 4
787 Discard the files before the named <file> from the output (i\&.e\&.
788 \fIskip to\fR), or move them to the end of the output (i\&.e\&.
789 \fIrotate to\fR)\&. These were invented primarily for use of the
790 \fBgit difftool\fR
791 command, and may not be very useful otherwise\&.
792 .RE
793 .PP
794 \-R
795 .RS 4
796 Swap two inputs; that is, show differences from index or on\-disk file to tree contents\&.
797 .RE
798 .PP
799 \-\-relative[=<path>], \-\-no\-relative
800 .RS 4
801 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\&.
802 \fB\-\-no\-relative\fR
803 can be used to countermand both
804 \fBdiff\&.relative\fR
805 config option and previous
806 \fB\-\-relative\fR\&.
807 .RE
808 .PP
809 \-a, \-\-text
810 .RS 4
811 Treat all files as text\&.
812 .RE
813 .PP
814 \-\-ignore\-cr\-at\-eol
815 .RS 4
816 Ignore carriage\-return at the end of line when doing a comparison\&.
817 .RE
818 .PP
819 \-\-ignore\-space\-at\-eol
820 .RS 4
821 Ignore changes in whitespace at EOL\&.
822 .RE
823 .PP
824 \-b, \-\-ignore\-space\-change
825 .RS 4
826 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\&.
827 .RE
828 .PP
829 \-w, \-\-ignore\-all\-space
830 .RS 4
831 Ignore whitespace when comparing lines\&. This ignores differences even if one line has whitespace where the other line has none\&.
832 .RE
833 .PP
834 \-\-ignore\-blank\-lines
835 .RS 4
836 Ignore changes whose lines are all blank\&.
837 .RE
838 .PP
839 \-I<regex>, \-\-ignore\-matching\-lines=<regex>
840 .RS 4
841 Ignore changes whose all lines match <regex>\&. This option may be specified more than once\&.
842 .RE
843 .PP
844 \-\-inter\-hunk\-context=<lines>
845 .RS 4
846 Show the context between diff hunks, up to the specified number of lines, thereby fusing hunks that are close to each other\&. Defaults to
847 \fBdiff\&.interHunkContext\fR
848 or 0 if the config option is unset\&.
849 .RE
850 .PP
851 \-W, \-\-function\-context
852 .RS 4
853 Show whole function as context lines for each change\&. The function names are determined in the same way as
854 \fBgit diff\fR
855 works out patch hunk headers (see
856 \fIDefining a custom hunk\-header\fR
857 in
858 \fBgitattributes\fR(5))\&.
859 .RE
860 .PP
861 \-\-exit\-code
862 .RS 4
863 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\&.
864 .RE
865 .PP
866 \-\-quiet
867 .RS 4
868 Disable all output of the program\&. Implies
869 \fB\-\-exit\-code\fR\&.
870 .RE
871 .PP
872 \-\-ext\-diff
873 .RS 4
874 Allow an external diff helper to be executed\&. If you set an external diff driver with
875 \fBgitattributes\fR(5), you need to use this option with
876 \fBgit-log\fR(1)
877 and friends\&.
878 .RE
879 .PP
880 \-\-no\-ext\-diff
881 .RS 4
882 Disallow external diff drivers\&.
883 .RE
884 .PP
885 \-\-textconv, \-\-no\-textconv
886 .RS 4
887 Allow (or disallow) external text conversion filters to be run when comparing binary files\&. See
888 \fBgitattributes\fR(5)
889 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
890 \fBgit-diff\fR(1)
891 and
892 \fBgit-log\fR(1), but not for
893 \fBgit-format-patch\fR(1)
894 or diff plumbing commands\&.
895 .RE
896 .PP
897 \-\-ignore\-submodules[=<when>]
898 .RS 4
899 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
900 \fIignore\fR
901 option in
902 \fBgit-config\fR(1)
903 or
904 \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\&.
905 .RE
906 .PP
907 \-\-src\-prefix=<prefix>
908 .RS 4
909 Show the given source prefix instead of "a/"\&.
910 .RE
911 .PP
912 \-\-dst\-prefix=<prefix>
913 .RS 4
914 Show the given destination prefix instead of "b/"\&.
915 .RE
916 .PP
917 \-\-no\-prefix
918 .RS 4
919 Do not show any source or destination prefix\&.
920 .RE
921 .PP
922 \-\-line\-prefix=<prefix>
923 .RS 4
924 Prepend an additional prefix to every line of output\&.
925 .RE
926 .PP
927 \-\-ita\-invisible\-in\-index
928 .RS 4
929 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
930 \fB\-\-ita\-visible\-in\-index\fR\&. Both options are experimental and could be removed in future\&.
931 .RE
932 .sp
933 For more detailed explanation on these common options, see also \fBgitdiffcore\fR(7)\&.
934 .PP
935 <tree\-ish>
936 .RS 4
937 The id of a tree object to diff against\&.
938 .RE
939 .PP
940 \-\-cached
941 .RS 4
942 Do not consider the on\-disk file at all\&.
943 .RE
944 .PP
945 \-\-merge\-base
946 .RS 4
947 Instead of comparing <tree\-ish> directly, use the merge base between <tree\-ish> and HEAD instead\&. <tree\-ish> must be a commit\&.
948 .RE
949 .PP
950 \-m
951 .RS 4
952 By default, files recorded in the index but not checked out are reported as deleted\&. This flag makes
953 \fIgit diff\-index\fR
954 say that all non\-checked\-out files are up to date\&.
955 .RE
956 .SH "RAW OUTPUT FORMAT"
957 .sp
958 The raw output format from "git\-diff\-index", "git\-diff\-tree", "git\-diff\-files" and "git diff \-\-raw" are very similar\&.
959 .sp
960 These commands all compare two sets of things; what is compared differs:
961 .PP
962 git\-diff\-index <tree\-ish>
963 .RS 4
964 compares the <tree\-ish> and the files on the filesystem\&.
965 .RE
966 .PP
967 git\-diff\-index \-\-cached <tree\-ish>
968 .RS 4
969 compares the <tree\-ish> and the index\&.
970 .RE
971 .PP
972 git\-diff\-tree [\-r] <tree\-ish\-1> <tree\-ish\-2> [<pattern>\&...]
973 .RS 4
974 compares the trees named by the two arguments\&.
975 .RE
976 .PP
977 git\-diff\-files [<pattern>\&...]
978 .RS 4
979 compares the index and the files on the filesystem\&.
980 .RE
981 .sp
982 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\&.
983 .sp
984 An output line is formatted this way:
985 .sp
986 .if n \{\
987 .RS 4
988 .\}
989 .nf
990 in\-place edit :100644 100644 bcd1234 0123456 M file0
991 copy\-edit :100644 100644 abcd123 1234567 C68 file1 file2
992 rename\-edit :100644 100644 abcd123 1234567 R86 file1 file3
993 create :000000 100644 0000000 1234567 A file4
994 delete :100644 000000 1234567 0000000 D file5
995 unmerged :000000 000000 0000000 0000000 U file6
996 .fi
997 .if n \{\
998 .RE
999 .\}
1000 .sp
1001 .sp
1002 That is, from the left to the right:
1003 .sp
1004 .RS 4
1005 .ie n \{\
1006 \h'-04' 1.\h'+01'\c
1007 .\}
1008 .el \{\
1009 .sp -1
1010 .IP " 1." 4.2
1011 .\}
1012 a colon\&.
1013 .RE
1014 .sp
1015 .RS 4
1016 .ie n \{\
1017 \h'-04' 2.\h'+01'\c
1018 .\}
1019 .el \{\
1020 .sp -1
1021 .IP " 2." 4.2
1022 .\}
1023 mode for "src"; 000000 if creation or unmerged\&.
1024 .RE
1025 .sp
1026 .RS 4
1027 .ie n \{\
1028 \h'-04' 3.\h'+01'\c
1029 .\}
1030 .el \{\
1031 .sp -1
1032 .IP " 3." 4.2
1033 .\}
1034 a space\&.
1035 .RE
1036 .sp
1037 .RS 4
1038 .ie n \{\
1039 \h'-04' 4.\h'+01'\c
1040 .\}
1041 .el \{\
1042 .sp -1
1043 .IP " 4." 4.2
1044 .\}
1045 mode for "dst"; 000000 if deletion or unmerged\&.
1046 .RE
1047 .sp
1048 .RS 4
1049 .ie n \{\
1050 \h'-04' 5.\h'+01'\c
1051 .\}
1052 .el \{\
1053 .sp -1
1054 .IP " 5." 4.2
1055 .\}
1056 a space\&.
1057 .RE
1058 .sp
1059 .RS 4
1060 .ie n \{\
1061 \h'-04' 6.\h'+01'\c
1062 .\}
1063 .el \{\
1064 .sp -1
1065 .IP " 6." 4.2
1066 .\}
1067 sha1 for "src"; 0{40} if creation or unmerged\&.
1068 .RE
1069 .sp
1070 .RS 4
1071 .ie n \{\
1072 \h'-04' 7.\h'+01'\c
1073 .\}
1074 .el \{\
1075 .sp -1
1076 .IP " 7." 4.2
1077 .\}
1078 a space\&.
1079 .RE
1080 .sp
1081 .RS 4
1082 .ie n \{\
1083 \h'-04' 8.\h'+01'\c
1084 .\}
1085 .el \{\
1086 .sp -1
1087 .IP " 8." 4.2
1088 .\}
1089 sha1 for "dst"; 0{40} if deletion, unmerged or "work tree out of sync with the index"\&.
1090 .RE
1091 .sp
1092 .RS 4
1093 .ie n \{\
1094 \h'-04' 9.\h'+01'\c
1095 .\}
1096 .el \{\
1097 .sp -1
1098 .IP " 9." 4.2
1099 .\}
1100 a space\&.
1101 .RE
1102 .sp
1103 .RS 4
1104 .ie n \{\
1105 \h'-04'10.\h'+01'\c
1106 .\}
1107 .el \{\
1108 .sp -1
1109 .IP "10." 4.2
1110 .\}
1111 status, followed by optional "score" number\&.
1112 .RE
1113 .sp
1114 .RS 4
1115 .ie n \{\
1116 \h'-04'11.\h'+01'\c
1117 .\}
1118 .el \{\
1119 .sp -1
1120 .IP "11." 4.2
1121 .\}
1122 a tab or a NUL when
1123 \fB\-z\fR
1124 option is used\&.
1125 .RE
1126 .sp
1127 .RS 4
1128 .ie n \{\
1129 \h'-04'12.\h'+01'\c
1130 .\}
1131 .el \{\
1132 .sp -1
1133 .IP "12." 4.2
1134 .\}
1135 path for "src"
1136 .RE
1137 .sp
1138 .RS 4
1139 .ie n \{\
1140 \h'-04'13.\h'+01'\c
1141 .\}
1142 .el \{\
1143 .sp -1
1144 .IP "13." 4.2
1145 .\}
1146 a tab or a NUL when
1147 \fB\-z\fR
1148 option is used; only exists for C or R\&.
1149 .RE
1150 .sp
1151 .RS 4
1152 .ie n \{\
1153 \h'-04'14.\h'+01'\c
1154 .\}
1155 .el \{\
1156 .sp -1
1157 .IP "14." 4.2
1158 .\}
1159 path for "dst"; only exists for C or R\&.
1160 .RE
1161 .sp
1162 .RS 4
1163 .ie n \{\
1164 \h'-04'15.\h'+01'\c
1165 .\}
1166 .el \{\
1167 .sp -1
1168 .IP "15." 4.2
1169 .\}
1170 an LF or a NUL when
1171 \fB\-z\fR
1172 option is used, to terminate the record\&.
1173 .RE
1174 .sp
1175 Possible status letters are:
1176 .sp
1177 .RS 4
1178 .ie n \{\
1179 \h'-04'\(bu\h'+03'\c
1180 .\}
1181 .el \{\
1182 .sp -1
1183 .IP \(bu 2.3
1184 .\}
1185 A: addition of a file
1186 .RE
1187 .sp
1188 .RS 4
1189 .ie n \{\
1190 \h'-04'\(bu\h'+03'\c
1191 .\}
1192 .el \{\
1193 .sp -1
1194 .IP \(bu 2.3
1195 .\}
1196 C: copy of a file into a new one
1197 .RE
1198 .sp
1199 .RS 4
1200 .ie n \{\
1201 \h'-04'\(bu\h'+03'\c
1202 .\}
1203 .el \{\
1204 .sp -1
1205 .IP \(bu 2.3
1206 .\}
1207 D: deletion of a file
1208 .RE
1209 .sp
1210 .RS 4
1211 .ie n \{\
1212 \h'-04'\(bu\h'+03'\c
1213 .\}
1214 .el \{\
1215 .sp -1
1216 .IP \(bu 2.3
1217 .\}
1218 M: modification of the contents or mode of a file
1219 .RE
1220 .sp
1221 .RS 4
1222 .ie n \{\
1223 \h'-04'\(bu\h'+03'\c
1224 .\}
1225 .el \{\
1226 .sp -1
1227 .IP \(bu 2.3
1228 .\}
1229 R: renaming of a file
1230 .RE
1231 .sp
1232 .RS 4
1233 .ie n \{\
1234 \h'-04'\(bu\h'+03'\c
1235 .\}
1236 .el \{\
1237 .sp -1
1238 .IP \(bu 2.3
1239 .\}
1240 T: change in the type of the file (regular file, symbolic link or submodule)
1241 .RE
1242 .sp
1243 .RS 4
1244 .ie n \{\
1245 \h'-04'\(bu\h'+03'\c
1246 .\}
1247 .el \{\
1248 .sp -1
1249 .IP \(bu 2.3
1250 .\}
1251 U: file is unmerged (you must complete the merge before it can be committed)
1252 .RE
1253 .sp
1254 .RS 4
1255 .ie n \{\
1256 \h'-04'\(bu\h'+03'\c
1257 .\}
1258 .el \{\
1259 .sp -1
1260 .IP \(bu 2.3
1261 .\}
1262 X: "unknown" change type (most probably a bug, please report it)
1263 .RE
1264 .sp
1265 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\&.
1266 .sp
1267 The sha1 for "dst" is shown as all 0\(cqs if a file on the filesystem is out of sync with the index\&.
1268 .sp
1269 Example:
1270 .sp
1271 .if n \{\
1272 .RS 4
1273 .\}
1274 .nf
1275 :100644 100644 5be4a4a 0000000 M file\&.c
1276 .fi
1277 .if n \{\
1278 .RE
1279 .\}
1280 .sp
1281 .sp
1282 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\&.
1283 .SH "DIFF FORMAT FOR MERGES"
1284 .sp
1285 "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:
1286 .sp
1287 .RS 4
1288 .ie n \{\
1289 \h'-04' 1.\h'+01'\c
1290 .\}
1291 .el \{\
1292 .sp -1
1293 .IP " 1." 4.2
1294 .\}
1295 there is a colon for each parent
1296 .RE
1297 .sp
1298 .RS 4
1299 .ie n \{\
1300 \h'-04' 2.\h'+01'\c
1301 .\}
1302 .el \{\
1303 .sp -1
1304 .IP " 2." 4.2
1305 .\}
1306 there are more "src" modes and "src" sha1
1307 .RE
1308 .sp
1309 .RS 4
1310 .ie n \{\
1311 \h'-04' 3.\h'+01'\c
1312 .\}
1313 .el \{\
1314 .sp -1
1315 .IP " 3." 4.2
1316 .\}
1317 status is concatenated status characters for each parent
1318 .RE
1319 .sp
1320 .RS 4
1321 .ie n \{\
1322 \h'-04' 4.\h'+01'\c
1323 .\}
1324 .el \{\
1325 .sp -1
1326 .IP " 4." 4.2
1327 .\}
1328 no optional "score" number
1329 .RE
1330 .sp
1331 .RS 4
1332 .ie n \{\
1333 \h'-04' 5.\h'+01'\c
1334 .\}
1335 .el \{\
1336 .sp -1
1337 .IP " 5." 4.2
1338 .\}
1339 tab\-separated pathname(s) of the file
1340 .RE
1341 .sp
1342 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\&.
1343 .sp
1344 Examples for \fB\-c\fR and \fB\-\-cc\fR without \fB\-\-combined\-all\-paths\fR:
1345 .sp
1346 .if n \{\
1347 .RS 4
1348 .\}
1349 .nf
1350 ::100644 100644 100644 fabadb8 cc95eb0 4866510 MM desc\&.c
1351 ::100755 100755 100755 52b7a2d 6d1ac04 d2ac7d7 RM bar\&.sh
1352 ::100644 100644 100644 e07d6c5 9042e82 ee91881 RR phooey\&.c
1353 .fi
1354 .if n \{\
1355 .RE
1356 .\}
1357 .sp
1358 .sp
1359 Examples when \fB\-\-combined\-all\-paths\fR added to either \fB\-c\fR or \fB\-\-cc\fR:
1360 .sp
1361 .if n \{\
1362 .RS 4
1363 .\}
1364 .nf
1365 ::100644 100644 100644 fabadb8 cc95eb0 4866510 MM desc\&.c desc\&.c desc\&.c
1366 ::100755 100755 100755 52b7a2d 6d1ac04 d2ac7d7 RM foo\&.sh bar\&.sh bar\&.sh
1367 ::100644 100644 100644 e07d6c5 9042e82 ee91881 RR fooey\&.c fuey\&.c phooey\&.c
1368 .fi
1369 .if n \{\
1370 .RE
1371 .\}
1372 .sp
1373 .sp
1374 Note that \fIcombined diff\fR lists only files which were modified from all parents\&.
1375 .SH "GENERATING PATCH TEXT WITH \-P"
1376 .sp
1377 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))\&.
1378 .sp
1379 What the \-p option produces is slightly different from the traditional diff format:
1380 .sp
1381 .RS 4
1382 .ie n \{\
1383 \h'-04' 1.\h'+01'\c
1384 .\}
1385 .el \{\
1386 .sp -1
1387 .IP " 1." 4.2
1388 .\}
1389 It is preceded with a "git diff" header that looks like this:
1390 .sp
1391 .if n \{\
1392 .RS 4
1393 .\}
1394 .nf
1395 diff \-\-git a/file1 b/file2
1396 .fi
1397 .if n \{\
1398 .RE
1399 .\}
1400 .sp
1401 The
1402 \fBa/\fR
1403 and
1404 \fBb/\fR
1405 filenames are the same unless rename/copy is involved\&. Especially, even for a creation or a deletion,
1406 \fB/dev/null\fR
1407 is
1408 \fInot\fR
1409 used in place of the
1410 \fBa/\fR
1411 or
1412 \fBb/\fR
1413 filenames\&.
1414 .sp
1415 When rename/copy is involved,
1416 \fBfile1\fR
1417 and
1418 \fBfile2\fR
1419 show the name of the source file of the rename/copy and the name of the file that rename/copy produces, respectively\&.
1420 .RE
1421 .sp
1422 .RS 4
1423 .ie n \{\
1424 \h'-04' 2.\h'+01'\c
1425 .\}
1426 .el \{\
1427 .sp -1
1428 .IP " 2." 4.2
1429 .\}
1430 It is followed by one or more extended header lines:
1431 .sp
1432 .if n \{\
1433 .RS 4
1434 .\}
1435 .nf
1436 old mode <mode>
1437 new mode <mode>
1438 deleted file mode <mode>
1439 new file mode <mode>
1440 copy from <path>
1441 copy to <path>
1442 rename from <path>
1443 rename to <path>
1444 similarity index <number>
1445 dissimilarity index <number>
1446 index <hash>\&.\&.<hash> <mode>
1447 .fi
1448 .if n \{\
1449 .RE
1450 .\}
1451 .sp
1452 File modes are printed as 6\-digit octal numbers including the file type and file permission bits\&.
1453 .sp
1454 Path names in extended headers do not include the
1455 \fBa/\fR
1456 and
1457 \fBb/\fR
1458 prefixes\&.
1459 .sp
1460 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\&.
1461 .sp
1462 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\&.
1463 .RE
1464 .sp
1465 .RS 4
1466 .ie n \{\
1467 \h'-04' 3.\h'+01'\c
1468 .\}
1469 .el \{\
1470 .sp -1
1471 .IP " 3." 4.2
1472 .\}
1473 Pathnames with "unusual" characters are quoted as explained for the configuration variable
1474 \fBcore\&.quotePath\fR
1475 (see
1476 \fBgit-config\fR(1))\&.
1477 .RE
1478 .sp
1479 .RS 4
1480 .ie n \{\
1481 \h'-04' 4.\h'+01'\c
1482 .\}
1483 .el \{\
1484 .sp -1
1485 .IP " 4." 4.2
1486 .\}
1487 All the
1488 \fBfile1\fR
1489 files in the output refer to files before the commit, and all the
1490 \fBfile2\fR
1491 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:
1492 .sp
1493 .if n \{\
1494 .RS 4
1495 .\}
1496 .nf
1497 diff \-\-git a/a b/b
1498 rename from a
1499 rename to b
1500 diff \-\-git a/b b/a
1501 rename from b
1502 rename to a
1503 .fi
1504 .if n \{\
1505 .RE
1506 .\}
1507 .RE
1508 .sp
1509 .RS 4
1510 .ie n \{\
1511 \h'-04' 5.\h'+01'\c
1512 .\}
1513 .el \{\
1514 .sp -1
1515 .IP " 5." 4.2
1516 .\}
1517 Hunk headers mention the name of the function to which the hunk applies\&. See "Defining a custom hunk\-header" in
1518 \fBgitattributes\fR(5)
1519 for details of how to tailor to this to specific languages\&.
1520 .RE
1521 .SH "COMBINED DIFF FORMAT"
1522 .sp
1523 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\&.
1524 .sp
1525 A "combined diff" format looks like this:
1526 .sp
1527 .if n \{\
1528 .RS 4
1529 .\}
1530 .nf
1531 diff \-\-combined describe\&.c
1532 index fabadb8,cc95eb0\&.\&.4866510
1533 \-\-\- a/describe\&.c
1534 +++ b/describe\&.c
1535 @@@ \-98,20 \-98,12 +98,20 @@@
1536 return (a_date > b_date) ? \-1 : (a_date == b_date) ? 0 : 1;
1537 }
1539 \- static void describe(char *arg)
1540 \-static void describe(struct commit *cmit, int last_one)
1541 ++static void describe(char *arg, int last_one)
1542 {
1543 + unsigned char sha1[20];
1544 + struct commit *cmit;
1545 struct commit_list *list;
1546 static int initialized = 0;
1547 struct commit_name *n;
1549 + if (get_sha1(arg, sha1) < 0)
1550 + usage(describe_usage);
1551 + cmit = lookup_commit_reference(sha1);
1552 + if (!cmit)
1553 + usage(describe_usage);
1554 +
1555 if (!initialized) {
1556 initialized = 1;
1557 for_each_ref(get_name);
1558 .fi
1559 .if n \{\
1560 .RE
1561 .\}
1562 .sp
1564 .sp
1565 .RS 4
1566 .ie n \{\
1567 \h'-04' 1.\h'+01'\c
1568 .\}
1569 .el \{\
1570 .sp -1
1571 .IP " 1." 4.2
1572 .\}
1573 It is preceded with a "git diff" header, that looks like this (when the
1574 \fB\-c\fR
1575 option is used):
1576 .sp
1577 .if n \{\
1578 .RS 4
1579 .\}
1580 .nf
1581 diff \-\-combined file
1582 .fi
1583 .if n \{\
1584 .RE
1585 .\}
1586 .sp
1587 or like this (when the
1588 \fB\-\-cc\fR
1589 option is used):
1590 .sp
1591 .if n \{\
1592 .RS 4
1593 .\}
1594 .nf
1595 diff \-\-cc file
1596 .fi
1597 .if n \{\
1598 .RE
1599 .\}
1600 .RE
1601 .sp
1602 .RS 4
1603 .ie n \{\
1604 \h'-04' 2.\h'+01'\c
1605 .\}
1606 .el \{\
1607 .sp -1
1608 .IP " 2." 4.2
1609 .\}
1610 It is followed by one or more extended header lines (this example shows a merge with two parents):
1611 .sp
1612 .if n \{\
1613 .RS 4
1614 .\}
1615 .nf
1616 index <hash>,<hash>\&.\&.<hash>
1617 mode <mode>,<mode>\&.\&.<mode>
1618 new file mode <mode>
1619 deleted file mode <mode>,<mode>
1620 .fi
1621 .if n \{\
1622 .RE
1623 .\}
1624 .sp
1625 The
1626 \fBmode <mode>,<mode>\&.\&.<mode>\fR
1627 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\&.
1628 .RE
1629 .sp
1630 .RS 4
1631 .ie n \{\
1632 \h'-04' 3.\h'+01'\c
1633 .\}
1634 .el \{\
1635 .sp -1
1636 .IP " 3." 4.2
1637 .\}
1638 It is followed by two\-line from\-file/to\-file header
1639 .sp
1640 .if n \{\
1641 .RS 4
1642 .\}
1643 .nf
1644 \-\-\- a/file
1645 +++ b/file
1646 .fi
1647 .if n \{\
1648 .RE
1649 .\}
1650 .sp
1651 Similar to two\-line header for traditional
1652 \fIunified\fR
1653 diff format,
1654 \fB/dev/null\fR
1655 is used to signal created or deleted files\&.
1656 .sp
1657 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
1658 .sp
1659 .if n \{\
1660 .RS 4
1661 .\}
1662 .nf
1663 \-\-\- a/file
1664 \-\-\- a/file
1665 \-\-\- a/file
1666 +++ b/file
1667 .fi
1668 .if n \{\
1669 .RE
1670 .\}
1671 .sp
1672 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\&.
1673 .RE
1674 .sp
1675 .RS 4
1676 .ie n \{\
1677 \h'-04' 4.\h'+01'\c
1678 .\}
1679 .el \{\
1680 .sp -1
1681 .IP " 4." 4.2
1682 .\}
1683 Chunk header format is modified to prevent people from accidentally feeding it to
1684 \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
1685 \fIindex\fR
1686 header:
1687 .sp
1688 .if n \{\
1689 .RS 4
1690 .\}
1691 .nf
1692 @@@ <from\-file\-range> <from\-file\-range> <to\-file\-range> @@@
1693 .fi
1694 .if n \{\
1695 .RE
1696 .\}
1697 .sp
1698 There are (number of parents + 1)
1699 \fB@\fR
1700 characters in the chunk header for combined diff format\&.
1701 .RE
1702 .sp
1703 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\&.
1704 .sp
1705 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)\&.
1706 .sp
1707 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)\&.
1708 .sp
1709 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")\&.
1710 .SH "OTHER DIFF FORMATS"
1711 .sp
1712 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\&.
1713 .sp
1714 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:
1715 .sp
1716 .if n \{\
1717 .RS 4
1718 .\}
1719 .nf
1720 arch/{i386 => x86}/Makefile | 4 +\-\-
1721 .fi
1722 .if n \{\
1723 .RE
1724 .\}
1725 .sp
1726 .sp
1727 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:
1728 .sp
1729 .if n \{\
1730 .RS 4
1731 .\}
1732 .nf
1733 1 2 README
1734 3 1 arch/{i386 => x86}/Makefile
1735 .fi
1736 .if n \{\
1737 .RE
1738 .\}
1739 .sp
1740 .sp
1741 That is, from left to right:
1742 .sp
1743 .RS 4
1744 .ie n \{\
1745 \h'-04' 1.\h'+01'\c
1746 .\}
1747 .el \{\
1748 .sp -1
1749 .IP " 1." 4.2
1750 .\}
1751 the number of added lines;
1752 .RE
1753 .sp
1754 .RS 4
1755 .ie n \{\
1756 \h'-04' 2.\h'+01'\c
1757 .\}
1758 .el \{\
1759 .sp -1
1760 .IP " 2." 4.2
1761 .\}
1762 a tab;
1763 .RE
1764 .sp
1765 .RS 4
1766 .ie n \{\
1767 \h'-04' 3.\h'+01'\c
1768 .\}
1769 .el \{\
1770 .sp -1
1771 .IP " 3." 4.2
1772 .\}
1773 the number of deleted lines;
1774 .RE
1775 .sp
1776 .RS 4
1777 .ie n \{\
1778 \h'-04' 4.\h'+01'\c
1779 .\}
1780 .el \{\
1781 .sp -1
1782 .IP " 4." 4.2
1783 .\}
1784 a tab;
1785 .RE
1786 .sp
1787 .RS 4
1788 .ie n \{\
1789 \h'-04' 5.\h'+01'\c
1790 .\}
1791 .el \{\
1792 .sp -1
1793 .IP " 5." 4.2
1794 .\}
1795 pathname (possibly with rename/copy information);
1796 .RE
1797 .sp
1798 .RS 4
1799 .ie n \{\
1800 \h'-04' 6.\h'+01'\c
1801 .\}
1802 .el \{\
1803 .sp -1
1804 .IP " 6." 4.2
1805 .\}
1806 a newline\&.
1807 .RE
1808 .sp
1809 When \fB\-z\fR output option is in effect, the output is formatted this way:
1810 .sp
1811 .if n \{\
1812 .RS 4
1813 .\}
1814 .nf
1815 1 2 README NUL
1816 3 1 NUL arch/i386/Makefile NUL arch/x86/Makefile NUL
1817 .fi
1818 .if n \{\
1819 .RE
1820 .\}
1821 .sp
1822 .sp
1823 That is:
1824 .sp
1825 .RS 4
1826 .ie n \{\
1827 \h'-04' 1.\h'+01'\c
1828 .\}
1829 .el \{\
1830 .sp -1
1831 .IP " 1." 4.2
1832 .\}
1833 the number of added lines;
1834 .RE
1835 .sp
1836 .RS 4
1837 .ie n \{\
1838 \h'-04' 2.\h'+01'\c
1839 .\}
1840 .el \{\
1841 .sp -1
1842 .IP " 2." 4.2
1843 .\}
1844 a tab;
1845 .RE
1846 .sp
1847 .RS 4
1848 .ie n \{\
1849 \h'-04' 3.\h'+01'\c
1850 .\}
1851 .el \{\
1852 .sp -1
1853 .IP " 3." 4.2
1854 .\}
1855 the number of deleted lines;
1856 .RE
1857 .sp
1858 .RS 4
1859 .ie n \{\
1860 \h'-04' 4.\h'+01'\c
1861 .\}
1862 .el \{\
1863 .sp -1
1864 .IP " 4." 4.2
1865 .\}
1866 a tab;
1867 .RE
1868 .sp
1869 .RS 4
1870 .ie n \{\
1871 \h'-04' 5.\h'+01'\c
1872 .\}
1873 .el \{\
1874 .sp -1
1875 .IP " 5." 4.2
1876 .\}
1877 a NUL (only exists if renamed/copied);
1878 .RE
1879 .sp
1880 .RS 4
1881 .ie n \{\
1882 \h'-04' 6.\h'+01'\c
1883 .\}
1884 .el \{\
1885 .sp -1
1886 .IP " 6." 4.2
1887 .\}
1888 pathname in preimage;
1889 .RE
1890 .sp
1891 .RS 4
1892 .ie n \{\
1893 \h'-04' 7.\h'+01'\c
1894 .\}
1895 .el \{\
1896 .sp -1
1897 .IP " 7." 4.2
1898 .\}
1899 a NUL (only exists if renamed/copied);
1900 .RE
1901 .sp
1902 .RS 4
1903 .ie n \{\
1904 \h'-04' 8.\h'+01'\c
1905 .\}
1906 .el \{\
1907 .sp -1
1908 .IP " 8." 4.2
1909 .\}
1910 pathname in postimage (only exists if renamed/copied);
1911 .RE
1912 .sp
1913 .RS 4
1914 .ie n \{\
1915 \h'-04' 9.\h'+01'\c
1916 .\}
1917 .el \{\
1918 .sp -1
1919 .IP " 9." 4.2
1920 .\}
1921 a NUL\&.
1922 .RE
1923 .sp
1924 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\&.
1925 .SH "OPERATING MODES"
1926 .sp
1927 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\&.
1928 .SH "CACHED MODE"
1929 .sp
1930 If \fB\-\-cached\fR is specified, it allows you to ask:
1931 .sp
1932 .if n \{\
1933 .RS 4
1934 .\}
1935 .nf
1936 show me the differences between HEAD and the current index
1937 contents (the ones I\(aqd write using \(aqgit write\-tree\(aq)
1938 .fi
1939 .if n \{\
1940 .RE
1941 .\}
1942 .sp
1943 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
1944 .sp
1945 .if n \{\
1946 .RS 4
1947 .\}
1948 .nf
1949 git diff\-index \-\-cached HEAD
1950 .fi
1951 .if n \{\
1952 .RE
1953 .\}
1954 .sp
1955 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:
1956 .sp
1957 .if n \{\
1958 .RS 4
1959 .\}
1960 .nf
1961 torvalds@ppc970:~/git> git diff\-index \-\-cached HEAD
1962 :100644 000000 4161aecc6700a2eb579e842af0b7f22b98443f74 0000000000000000000000000000000000000000 D commit\&.c
1963 :000000 100644 0000000000000000000000000000000000000000 4161aecc6700a2eb579e842af0b7f22b98443f74 A git\-commit\&.c
1964 .fi
1965 .if n \{\
1966 .RE
1967 .\}
1968 .sp
1969 You can see easily that the above is a rename\&.
1970 .sp
1971 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\&.
1972 .sp
1973 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"\&.
1974 .SH "NON\-CACHED MODE"
1975 .sp
1976 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:
1977 .sp
1978 .if n \{\
1979 .RS 4
1980 .\}
1981 .nf
1982 show me the differences between HEAD and the currently checked out
1983 tree \- index contents _and_ files that aren\(aqt up to date
1984 .fi
1985 .if n \{\
1986 .RE
1987 .\}
1988 .sp
1989 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\&.
1990 .sp
1991 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:
1992 .sp
1993 .if n \{\
1994 .RS 4
1995 .\}
1996 .nf
1997 torvalds@ppc970:~/v2\&.6/linux> git diff\-index \-\-abbrev HEAD
1998 :100644 100644 7476bb5ba 000000000 M kernel/sched\&.c
1999 .fi
2000 .if n \{\
2001 .RE
2002 .\}
2003 .sp
2004 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\&.
2005 .if n \{\
2006 .sp
2007 .\}
2008 .RS 4
2009 .it 1 an-trap
2010 .nr an-no-space-flag 1
2011 .nr an-break-flag 1
2012 .br
2013 .ps +1
2014 \fBNote\fR
2015 .ps -1
2016 .br
2017 .sp
2018 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\&.
2019 .sp .5v
2020 .RE
2021 .if n \{\
2022 .sp
2023 .\}
2024 .RS 4
2025 .it 1 an-trap
2026 .nr an-no-space-flag 1
2027 .nr an-break-flag 1
2028 .br
2029 .ps +1
2030 \fBNote\fR
2031 .ps -1
2032 .br
2033 .sp
2034 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\&.
2035 .sp .5v
2036 .RE
2037 .SH "GIT"
2038 .sp
2039 Part of the \fBgit\fR(1) suite