run-command: dup_devnull(): guard against syscalls failing
[git/git.git] / Documentation / diff-options.txt
1 // Please don't remove this comment as asciidoc behaves badly when
2 // the first non-empty line is ifdef/ifndef. The symptom is that
3 // without this comment the <git-diff-core> attribute conditionally
4 // defined below ends up being defined unconditionally.
5 // Last checked with asciidoc 7.0.2.
7 ifndef::git-format-patch[]
8 ifndef::git-diff[]
9 ifndef::git-log[]
10 :git-diff-core: 1
11 endif::git-log[]
12 endif::git-diff[]
13 endif::git-format-patch[]
15 ifdef::git-format-patch[]
16 -p::
17 --no-stat::
18 Generate plain patches without any diffstats.
19 endif::git-format-patch[]
21 ifndef::git-format-patch[]
22 -p::
23 -u::
24 --patch::
25 Generate patch (see section on generating patches).
26 {git-diff? This is the default.}
27 endif::git-format-patch[]
29 -U<n>::
30 --unified=<n>::
31 Generate diffs with <n> lines of context instead of
32 the usual three.
33 ifndef::git-format-patch[]
34 Implies `-p`.
35 endif::git-format-patch[]
37 ifndef::git-format-patch[]
38 --raw::
39 Generate the raw format.
40 {git-diff-core? This is the default.}
41 endif::git-format-patch[]
43 ifndef::git-format-patch[]
44 --patch-with-raw::
45 Synonym for `-p --raw`.
46 endif::git-format-patch[]
48 --minimal::
49 Spend extra time to make sure the smallest possible
50 diff is produced.
52 --patience::
53 Generate a diff using the "patience diff" algorithm.
55 --histogram::
56 Generate a diff using the "histogram diff" algorithm.
58 --stat[=<width>[,<name-width>[,<count>]]]::
59 Generate a diffstat. By default, as much space as necessary
60 will be used for the filename part, and the rest for the graph
61 part. Maximum width defaults to terminal width, or 80 columns
62 if not connected to a terminal, and can be overridden by
63 `<width>`. The width of the filename part can be limited by
64 giving another width `<name-width>` after a comma. The width
65 of the graph part can be limited by using
66 `--stat-graph-width=<width>` (affects all commands generating
67 a stat graph) or by setting `diff.statGraphWidth=<width>`
68 (does not affect `git format-patch`).
69 By giving a third parameter `<count>`, you can limit the
70 output to the first `<count>` lines, followed by `...` if
71 there are more.
72 +
73 These parameters can also be set individually with `--stat-width=<width>`,
74 `--stat-name-width=<name-width>` and `--stat-count=<count>`.
76 --numstat::
77 Similar to `--stat`, but shows number of added and
78 deleted lines in decimal notation and pathname without
79 abbreviation, to make it more machine friendly. For
80 binary files, outputs two `-` instead of saying
81 `0 0`.
83 --shortstat::
84 Output only the last line of the `--stat` format containing total
85 number of modified files, as well as number of added and deleted
86 lines.
88 --dirstat[=<param1,param2,...>]::
89 Output the distribution of relative amount of changes for each
90 sub-directory. The behavior of `--dirstat` can be customized by
91 passing it a comma separated list of parameters.
92 The defaults are controlled by the `diff.dirstat` configuration
93 variable (see linkgit:git-config[1]).
94 The following parameters are available:
95 +
96 --
97 `changes`;;
98 Compute the dirstat numbers by counting the lines that have been
99 removed from the source, or added to the destination. This ignores
100 the amount of pure code movements within a file. In other words,
101 rearranging lines in a file is not counted as much as other changes.
102 This is the default behavior when no parameter is given.
103 `lines`;;
104 Compute the dirstat numbers by doing the regular line-based diff
105 analysis, and summing the removed/added line counts. (For binary
106 files, count 64-byte chunks instead, since binary files have no
107 natural concept of lines). This is a more expensive `--dirstat`
108 behavior than the `changes` behavior, but it does count rearranged
109 lines within a file as much as other changes. The resulting output
110 is consistent with what you get from the other `--*stat` options.
111 `files`;;
112 Compute the dirstat numbers by counting the number of files changed.
113 Each changed file counts equally in the dirstat analysis. This is
114 the computationally cheapest `--dirstat` behavior, since it does
115 not have to look at the file contents at all.
116 `cumulative`;;
117 Count changes in a child directory for the parent directory as well.
118 Note that when using `cumulative`, the sum of the percentages
119 reported may exceed 100%. The default (non-cumulative) behavior can
120 be specified with the `noncumulative` parameter.
121 <limit>;;
122 An integer parameter specifies a cut-off percent (3% by default).
123 Directories contributing less than this percentage of the changes
124 are not shown in the output.
125 --
126 +
127 Example: The following will count changed files, while ignoring
128 directories with less than 10% of the total amount of changed files,
129 and accumulating child directory counts in the parent directories:
130 `--dirstat=files,10,cumulative`.
132 --summary::
133 Output a condensed summary of extended header information
134 such as creations, renames and mode changes.
136 ifndef::git-format-patch[]
137 --patch-with-stat::
138 Synonym for `-p --stat`.
139 endif::git-format-patch[]
141 ifndef::git-format-patch[]
143 -z::
144 ifdef::git-log[]
145 Separate the commits with NULs instead of with new newlines.
146 +
147 Also, when `--raw` or `--numstat` has been given, do not munge
148 pathnames and use NULs as output field terminators.
149 endif::git-log[]
150 ifndef::git-log[]
151 When `--raw`, `--numstat`, `--name-only` or `--name-status` has been
152 given, do not munge pathnames and use NULs as output field terminators.
153 endif::git-log[]
154 +
155 Without this option, each pathname output will have TAB, LF, double quotes,
156 and backslash characters replaced with `\t`, `\n`, `\"`, and `\\`,
157 respectively, and the pathname will be enclosed in double quotes if
158 any of those replacements occurred.
160 --name-only::
161 Show only names of changed files.
163 --name-status::
164 Show only names and status of changed files. See the description
165 of the `--diff-filter` option on what the status letters mean.
167 --submodule[=<format>]::
168 Specify how differences in submodules are shown. When `--submodule`
169 or `--submodule=log` is given, the 'log' format is used. This format lists
170 the commits in the range like linkgit:git-submodule[1] `summary` does.
171 Omitting the `--submodule` option or specifying `--submodule=short`,
172 uses the 'short' format. This format just shows the names of the commits
173 at the beginning and end of the range. Can be tweaked via the
174 `diff.submodule` configuration variable.
176 --color[=<when>]::
177 Show colored diff.
178 `--color` (i.e. without '=<when>') is the same as `--color=always`.
179 '<when>' can be one of `always`, `never`, or `auto`.
180 ifdef::git-diff[]
181 It can be changed by the `color.ui` and `color.diff`
182 configuration settings.
183 endif::git-diff[]
185 --no-color::
186 Turn off colored diff.
187 ifdef::git-diff[]
188 This can be used to override configuration settings.
189 endif::git-diff[]
190 It is the same as `--color=never`.
192 --word-diff[=<mode>]::
193 Show a word diff, using the <mode> to delimit changed words.
194 By default, words are delimited by whitespace; see
195 `--word-diff-regex` below. The <mode> defaults to 'plain', and
196 must be one of:
197 +
198 --
199 color::
200 Highlight changed words using only colors. Implies `--color`.
201 plain::
202 Show words as `[-removed-]` and `{+added+}`. Makes no
203 attempts to escape the delimiters if they appear in the input,
204 so the output may be ambiguous.
205 porcelain::
206 Use a special line-based format intended for script
207 consumption. Added/removed/unchanged runs are printed in the
208 usual unified diff format, starting with a `+`/`-`/` `
209 character at the beginning of the line and extending to the
210 end of the line. Newlines in the input are represented by a
211 tilde `~` on a line of its own.
212 none::
213 Disable word diff again.
214 --
215 +
216 Note that despite the name of the first mode, color is used to
217 highlight the changed parts in all modes if enabled.
219 --word-diff-regex=<regex>::
220 Use <regex> to decide what a word is, instead of considering
221 runs of non-whitespace to be a word. Also implies
222 `--word-diff` unless it was already enabled.
223 +
224 Every non-overlapping match of the
225 <regex> is considered a word. Anything between these matches is
226 considered whitespace and ignored(!) for the purposes of finding
227 differences. You may want to append `|[^[:space:]]` to your regular
228 expression to make sure that it matches all non-whitespace characters.
229 A match that contains a newline is silently truncated(!) at the
230 newline.
231 +
232 The regex can also be set via a diff driver or configuration option, see
233 linkgit:gitattributes[1] or linkgit:git-config[1]. Giving it explicitly
234 overrides any diff driver or configuration setting. Diff drivers
235 override configuration settings.
237 --color-words[=<regex>]::
238 Equivalent to `--word-diff=color` plus (if a regex was
239 specified) `--word-diff-regex=<regex>`.
240 endif::git-format-patch[]
242 --no-renames::
243 Turn off rename detection, even when the configuration
244 file gives the default to do so.
246 ifndef::git-format-patch[]
247 --check::
248 Warn if changes introduce whitespace errors. What are
249 considered whitespace errors is controlled by `core.whitespace`
250 configuration. By default, trailing whitespaces (including
251 lines that solely consist of whitespaces) and a space character
252 that is immediately followed by a tab character inside the
253 initial indent of the line are considered whitespace errors.
254 Exits with non-zero status if problems are found. Not compatible
255 with --exit-code.
256 endif::git-format-patch[]
258 --full-index::
259 Instead of the first handful of characters, show the full
260 pre- and post-image blob object names on the "index"
261 line when generating patch format output.
263 --binary::
264 In addition to `--full-index`, output a binary diff that
265 can be applied with `git-apply`.
267 --abbrev[=<n>]::
268 Instead of showing the full 40-byte hexadecimal object
269 name in diff-raw format output and diff-tree header
270 lines, show only a partial prefix. This is
271 independent of the `--full-index` option above, which controls
272 the diff-patch output format. Non default number of
273 digits can be specified with `--abbrev=<n>`.
275 -B[<n>][/<m>]::
276 --break-rewrites[=[<n>][/<m>]]::
277 Break complete rewrite changes into pairs of delete and
278 create. This serves two purposes:
279 +
280 It affects the way a change that amounts to a total rewrite of a file
281 not as a series of deletion and insertion mixed together with a very
282 few lines that happen to match textually as the context, but as a
283 single deletion of everything old followed by a single insertion of
284 everything new, and the number `m` controls this aspect of the -B
285 option (defaults to 60%). `-B/70%` specifies that less than 30% of the
286 original should remain in the result for git to consider it a total
287 rewrite (i.e. otherwise the resulting patch will be a series of
288 deletion and insertion mixed together with context lines).
289 +
290 When used with -M, a totally-rewritten file is also considered as the
291 source of a rename (usually -M only considers a file that disappeared
292 as the source of a rename), and the number `n` controls this aspect of
293 the -B option (defaults to 50%). `-B20%` specifies that a change with
294 addition and deletion compared to 20% or more of the file's size are
295 eligible for being picked up as a possible source of a rename to
296 another file.
298 -M[<n>]::
299 --find-renames[=<n>]::
300 ifndef::git-log[]
301 Detect renames.
302 endif::git-log[]
303 ifdef::git-log[]
304 If generating diffs, detect and report renames for each commit.
305 For following files across renames while traversing history, see
306 `--follow`.
307 endif::git-log[]
308 If `n` is specified, it is a threshold on the similarity
309 index (i.e. amount of addition/deletions compared to the
310 file's size). For example, `-M90%` means git should consider a
311 delete/add pair to be a rename if more than 90% of the file
312 hasn't changed. Without a `%` sign, the number is to be read as
313 a fraction, with a decimal point before it. I.e., `-M5` becomes
314 0.5, and is thus the same as `-M50%`. Similarly, `-M05` is
315 the same as `-M5%`. To limit detection to exact renames, use
316 `-M100%`.
318 -C[<n>]::
319 --find-copies[=<n>]::
320 Detect copies as well as renames. See also `--find-copies-harder`.
321 If `n` is specified, it has the same meaning as for `-M<n>`.
323 --find-copies-harder::
324 For performance reasons, by default, `-C` option finds copies only
325 if the original file of the copy was modified in the same
326 changeset. This flag makes the command
327 inspect unmodified files as candidates for the source of
328 copy. This is a very expensive operation for large
329 projects, so use it with caution. Giving more than one
330 `-C` option has the same effect.
332 -D::
333 --irreversible-delete::
334 Omit the preimage for deletes, i.e. print only the header but not
335 the diff between the preimage and `/dev/null`. The resulting patch
336 is not meant to be applied with `patch` nor `git apply`; this is
337 solely for people who want to just concentrate on reviewing the
338 text after the change. In addition, the output obviously lack
339 enough information to apply such a patch in reverse, even manually,
340 hence the name of the option.
341 +
342 When used together with `-B`, omit also the preimage in the deletion part
343 of a delete/create pair.
345 -l<num>::
346 The `-M` and `-C` options require O(n^2) processing time where n
347 is the number of potential rename/copy targets. This
348 option prevents rename/copy detection from running if
349 the number of rename/copy targets exceeds the specified
350 number.
352 ifndef::git-format-patch[]
353 --diff-filter=[(A|C|D|M|R|T|U|X|B)...[*]]::
354 Select only files that are Added (`A`), Copied (`C`),
355 Deleted (`D`), Modified (`M`), Renamed (`R`), have their
356 type (i.e. regular file, symlink, submodule, ...) changed (`T`),
357 are Unmerged (`U`), are
358 Unknown (`X`), or have had their pairing Broken (`B`).
359 Any combination of the filter characters (including none) can be used.
360 When `*` (All-or-none) is added to the combination, all
361 paths are selected if there is any file that matches
362 other criteria in the comparison; if there is no file
363 that matches other criteria, nothing is selected.
365 -S<string>::
366 Look for differences that introduce or remove an instance of
367 <string>. Note that this is different than the string simply
368 appearing in diff output; see the 'pickaxe' entry in
369 linkgit:gitdiffcore[7] for more details.
371 -G<regex>::
372 Look for differences whose added or removed line matches
373 the given <regex>.
375 --pickaxe-all::
376 When `-S` or `-G` finds a change, show all the changes in that
377 changeset, not just the files that contain the change
378 in <string>.
380 --pickaxe-regex::
381 Make the <string> not a plain string but an extended POSIX
382 regex to match.
383 endif::git-format-patch[]
385 -O<orderfile>::
386 Output the patch in the order specified in the
387 <orderfile>, which has one shell glob pattern per line.
389 ifndef::git-format-patch[]
390 -R::
391 Swap two inputs; that is, show differences from index or
392 on-disk file to tree contents.
394 --relative[=<path>]::
395 When run from a subdirectory of the project, it can be
396 told to exclude changes outside the directory and show
397 pathnames relative to it with this option. When you are
398 not in a subdirectory (e.g. in a bare repository), you
399 can name which subdirectory to make the output relative
400 to by giving a <path> as an argument.
401 endif::git-format-patch[]
403 -a::
404 --text::
405 Treat all files as text.
407 --ignore-space-at-eol::
408 Ignore changes in whitespace at EOL.
410 -b::
411 --ignore-space-change::
412 Ignore changes in amount of whitespace. This ignores whitespace
413 at line end, and considers all other sequences of one or
414 more whitespace characters to be equivalent.
416 -w::
417 --ignore-all-space::
418 Ignore whitespace when comparing lines. This ignores
419 differences even if one line has whitespace where the other
420 line has none.
422 --inter-hunk-context=<lines>::
423 Show the context between diff hunks, up to the specified number
424 of lines, thereby fusing hunks that are close to each other.
426 -W::
427 --function-context::
428 Show whole surrounding functions of changes.
430 ifndef::git-format-patch[]
431 ifndef::git-log[]
432 --exit-code::
433 Make the program exit with codes similar to diff(1).
434 That is, it exits with 1 if there were differences and
435 0 means no differences.
437 --quiet::
438 Disable all output of the program. Implies `--exit-code`.
439 endif::git-log[]
440 endif::git-format-patch[]
442 --ext-diff::
443 Allow an external diff helper to be executed. If you set an
444 external diff driver with linkgit:gitattributes[5], you need
445 to use this option with linkgit:git-log[1] and friends.
447 --no-ext-diff::
448 Disallow external diff drivers.
450 --textconv::
451 --no-textconv::
452 Allow (or disallow) external text conversion filters to be run
453 when comparing binary files. See linkgit:gitattributes[5] for
454 details. Because textconv filters are typically a one-way
455 conversion, the resulting diff is suitable for human
456 consumption, but cannot be applied. For this reason, textconv
457 filters are enabled by default only for linkgit:git-diff[1] and
458 linkgit:git-log[1], but not for linkgit:git-format-patch[1] or
459 diff plumbing commands.
461 --ignore-submodules[=<when>]::
462 Ignore changes to submodules in the diff generation. <when> can be
463 either "none", "untracked", "dirty" or "all", which is the default
464 Using "none" will consider the submodule modified when it either contains
465 untracked or modified files or its HEAD differs from the commit recorded
466 in the superproject and can be used to override any settings of the
467 'ignore' option in linkgit:git-config[1] or linkgit:gitmodules[5]. When
468 "untracked" is used submodules are not considered dirty when they only
469 contain untracked content (but they are still scanned for modified
470 content). Using "dirty" ignores all changes to the work tree of submodules,
471 only changes to the commits stored in the superproject are shown (this was
472 the behavior until 1.7.0). Using "all" hides all changes to submodules.
474 --src-prefix=<prefix>::
475 Show the given source prefix instead of "a/".
477 --dst-prefix=<prefix>::
478 Show the given destination prefix instead of "b/".
480 --no-prefix::
481 Do not show any source or destination prefix.
483 For more detailed explanation on these common options, see also
484 linkgit:gitdiffcore[7].