rev-parse --branches/--tags/--remotes=pattern
[git/git.git] / Documentation / git-rev-parse.txt
1 git-rev-parse(1)
2 ================
3
4 NAME
5 ----
6 git-rev-parse - Pick out and massage parameters
7
8
9 SYNOPSIS
10 --------
11 'git rev-parse' [ --option ] <args>...
12
13 DESCRIPTION
14 -----------
15
16 Many git porcelainish commands take mixture of flags
17 (i.e. parameters that begin with a dash '-') and parameters
18 meant for the underlying 'git-rev-list' command they use internally
19 and flags and parameters for the other commands they use
20 downstream of 'git-rev-list'. This command is used to
21 distinguish between them.
22
23
24 OPTIONS
25 -------
26 --parseopt::
27 Use 'git-rev-parse' in option parsing mode (see PARSEOPT section below).
28
29 --keep-dashdash::
30 Only meaningful in `--parseopt` mode. Tells the option parser to echo
31 out the first `--` met instead of skipping it.
32
33 --stop-at-non-option::
34 Only meaningful in `--parseopt` mode. Lets the option parser stop at
35 the first non-option argument. This can be used to parse sub-commands
36 that take options themself.
37
38 --sq-quote::
39 Use 'git-rev-parse' in shell quoting mode (see SQ-QUOTE
40 section below). In contrast to the `--sq` option below, this
41 mode does only quoting. Nothing else is done to command input.
42
43 --revs-only::
44 Do not output flags and parameters not meant for
45 'git-rev-list' command.
46
47 --no-revs::
48 Do not output flags and parameters meant for
49 'git-rev-list' command.
50
51 --flags::
52 Do not output non-flag parameters.
53
54 --no-flags::
55 Do not output flag parameters.
56
57 --default <arg>::
58 If there is no parameter given by the user, use `<arg>`
59 instead.
60
61 --verify::
62 The parameter given must be usable as a single, valid
63 object name. Otherwise barf and abort.
64
65 -q::
66 --quiet::
67 Only meaningful in `--verify` mode. Do not output an error
68 message if the first argument is not a valid object name;
69 instead exit with non-zero status silently.
70
71 --sq::
72 Usually the output is made one line per flag and
73 parameter. This option makes output a single line,
74 properly quoted for consumption by shell. Useful when
75 you expect your parameter to contain whitespaces and
76 newlines (e.g. when using pickaxe `-S` with
77 'git-diff-\*'). In contrast to the `--sq-quote` option,
78 the command input is still interpreted as usual.
79
80 --not::
81 When showing object names, prefix them with '{caret}' and
82 strip '{caret}' prefix from the object names that already have
83 one.
84
85 --symbolic::
86 Usually the object names are output in SHA1 form (with
87 possible '{caret}' prefix); this option makes them output in a
88 form as close to the original input as possible.
89
90 --symbolic-full-name::
91 This is similar to \--symbolic, but it omits input that
92 are not refs (i.e. branch or tag names; or more
93 explicitly disambiguating "heads/master" form, when you
94 want to name the "master" branch when there is an
95 unfortunately named tag "master"), and show them as full
96 refnames (e.g. "refs/heads/master").
97
98 --abbrev-ref[={strict|loose}]::
99 A non-ambiguous short name of the objects name.
100 The option core.warnAmbiguousRefs is used to select the strict
101 abbreviation mode.
102
103 --all::
104 Show all refs found in `$GIT_DIR/refs`.
105
106 --branches[=pattern]::
107 Show branch refs found in `$GIT_DIR/refs/heads`. If `pattern`
108 is given, only branches matching given shell glob are shown.
109 If pattern lacks '?', '*', or '[', '/*' at the end is impiled.
110
111 --tags[=pattern]::
112 Show tag refs found in `$GIT_DIR/refs/tags`. If `pattern`
113 is given, only tags matching given shell glob are shown.
114 If pattern lacks '?', '*', or '[', '/*' at the end is impiled.
115
116 --remotes[=pattern]::
117 Show tag refs found in `$GIT_DIR/refs/remotes`. If `pattern`
118 is given, only remote tracking branches matching given shell glob
119 are shown. If pattern lacks '?', '*', or '[', '/*' at the end is
120 impiled.
121
122 --glob=glob-pattern::
123 Show refs matching shell glob pattern `glob-pattern`. If pattern
124 specified lacks leading 'refs/', it is automatically prepended.
125 If pattern lacks '?', '*', or '[', '/*' at the end is impiled.
126
127 --show-prefix::
128 When the command is invoked from a subdirectory, show the
129 path of the current directory relative to the top-level
130 directory.
131
132 --show-cdup::
133 When the command is invoked from a subdirectory, show the
134 path of the top-level directory relative to the current
135 directory (typically a sequence of "../", or an empty string).
136
137 --git-dir::
138 Show `$GIT_DIR` if defined else show the path to the .git directory.
139
140 --is-inside-git-dir::
141 When the current working directory is below the repository
142 directory print "true", otherwise "false".
143
144 --is-inside-work-tree::
145 When the current working directory is inside the work tree of the
146 repository print "true", otherwise "false".
147
148 --is-bare-repository::
149 When the repository is bare print "true", otherwise "false".
150
151 --short::
152 --short=number::
153 Instead of outputting the full SHA1 values of object names try to
154 abbreviate them to a shorter unique name. When no length is specified
155 7 is used. The minimum length is 4.
156
157 --since=datestring::
158 --after=datestring::
159 Parse the date string, and output the corresponding
160 --max-age= parameter for 'git-rev-list'.
161
162 --until=datestring::
163 --before=datestring::
164 Parse the date string, and output the corresponding
165 --min-age= parameter for 'git-rev-list'.
166
167 <args>...::
168 Flags and parameters to be parsed.
169
170
171 SPECIFYING REVISIONS
172 --------------------
173
174 A revision parameter typically, but not necessarily, names a
175 commit object. They use what is called an 'extended SHA1'
176 syntax. Here are various ways to spell object names. The
177 ones listed near the end of this list are to name trees and
178 blobs contained in a commit.
179
180 * The full SHA1 object name (40-byte hexadecimal string), or
181 a substring of such that is unique within the repository.
182 E.g. dae86e1950b1277e545cee180551750029cfe735 and dae86e both
183 name the same commit object if there are no other object in
184 your repository whose object name starts with dae86e.
185
186 * An output from 'git-describe'; i.e. a closest tag, optionally
187 followed by a dash and a number of commits, followed by a dash, a
188 `g`, and an abbreviated object name.
189
190 * A symbolic ref name. E.g. 'master' typically means the commit
191 object referenced by $GIT_DIR/refs/heads/master. If you
192 happen to have both heads/master and tags/master, you can
193 explicitly say 'heads/master' to tell git which one you mean.
194 When ambiguous, a `<name>` is disambiguated by taking the
195 first match in the following rules:
196
197 . if `$GIT_DIR/<name>` exists, that is what you mean (this is usually
198 useful only for `HEAD`, `FETCH_HEAD`, `ORIG_HEAD` and `MERGE_HEAD`);
199
200 . otherwise, `$GIT_DIR/refs/<name>` if exists;
201
202 . otherwise, `$GIT_DIR/refs/tags/<name>` if exists;
203
204 . otherwise, `$GIT_DIR/refs/heads/<name>` if exists;
205
206 . otherwise, `$GIT_DIR/refs/remotes/<name>` if exists;
207
208 . otherwise, `$GIT_DIR/refs/remotes/<name>/HEAD` if exists.
209 +
210 HEAD names the commit your changes in the working tree is based on.
211 FETCH_HEAD records the branch you fetched from a remote repository
212 with your last 'git-fetch' invocation.
213 ORIG_HEAD is created by commands that moves your HEAD in a drastic
214 way, to record the position of the HEAD before their operation, so that
215 you can change the tip of the branch back to the state before you ran
216 them easily.
217 MERGE_HEAD records the commit(s) you are merging into your branch
218 when you run 'git-merge'.
219
220 * A ref followed by the suffix '@' with a date specification
221 enclosed in a brace
222 pair (e.g. '\{yesterday\}', '\{1 month 2 weeks 3 days 1 hour 1
223 second ago\}' or '\{1979-02-26 18:30:00\}') to specify the value
224 of the ref at a prior point in time. This suffix may only be
225 used immediately following a ref name and the ref must have an
226 existing log ($GIT_DIR/logs/<ref>). Note that this looks up the state
227 of your *local* ref at a given time; e.g., what was in your local
228 `master` branch last week. If you want to look at commits made during
229 certain times, see `--since` and `--until`.
230
231 * A ref followed by the suffix '@' with an ordinal specification
232 enclosed in a brace pair (e.g. '\{1\}', '\{15\}') to specify
233 the n-th prior value of that ref. For example 'master@\{1\}'
234 is the immediate prior value of 'master' while 'master@\{5\}'
235 is the 5th prior value of 'master'. This suffix may only be used
236 immediately following a ref name and the ref must have an existing
237 log ($GIT_DIR/logs/<ref>).
238
239 * You can use the '@' construct with an empty ref part to get at a
240 reflog of the current branch. For example, if you are on the
241 branch 'blabla', then '@\{1\}' means the same as 'blabla@\{1\}'.
242
243 * The special construct '@\{-<n>\}' means the <n>th branch checked out
244 before the current one.
245
246 * A suffix '{caret}' to a revision parameter means the first parent of
247 that commit object. '{caret}<n>' means the <n>th parent (i.e.
248 'rev{caret}'
249 is equivalent to 'rev{caret}1'). As a special rule,
250 'rev{caret}0' means the commit itself and is used when 'rev' is the
251 object name of a tag object that refers to a commit object.
252
253 * A suffix '{tilde}<n>' to a revision parameter means the commit
254 object that is the <n>th generation grand-parent of the named
255 commit object, following only the first parent. I.e. rev~3 is
256 equivalent to rev{caret}{caret}{caret} which is equivalent to
257 rev{caret}1{caret}1{caret}1. See below for a illustration of
258 the usage of this form.
259
260 * A suffix '{caret}' followed by an object type name enclosed in
261 brace pair (e.g. `v0.99.8{caret}\{commit\}`) means the object
262 could be a tag, and dereference the tag recursively until an
263 object of that type is found or the object cannot be
264 dereferenced anymore (in which case, barf). `rev{caret}0`
265 introduced earlier is a short-hand for `rev{caret}\{commit\}`.
266
267 * A suffix '{caret}' followed by an empty brace pair
268 (e.g. `v0.99.8{caret}\{\}`) means the object could be a tag,
269 and dereference the tag recursively until a non-tag object is
270 found.
271
272 * A colon, followed by a slash, followed by a text: this names
273 a commit whose commit message starts with the specified text.
274 This name returns the youngest matching commit which is
275 reachable from any ref. If the commit message starts with a
276 '!', you have to repeat that; the special sequence ':/!',
277 followed by something else than '!' is reserved for now.
278
279 * A suffix ':' followed by a path; this names the blob or tree
280 at the given path in the tree-ish object named by the part
281 before the colon.
282
283 * A colon, optionally followed by a stage number (0 to 3) and a
284 colon, followed by a path; this names a blob object in the
285 index at the given path. Missing stage number (and the colon
286 that follows it) names a stage 0 entry. During a merge, stage
287 1 is the common ancestor, stage 2 is the target branch's version
288 (typically the current branch), and stage 3 is the version from
289 the branch being merged.
290
291 Here is an illustration, by Jon Loeliger. Both commit nodes B
292 and C are parents of commit node A. Parent commits are ordered
293 left-to-right.
294
295 ........................................
296 G H I J
297 \ / \ /
298 D E F
299 \ | / \
300 \ | / |
301 \|/ |
302 B C
303 \ /
304 \ /
305 A
306 ........................................
307
308 A = = A^0
309 B = A^ = A^1 = A~1
310 C = A^2 = A^2
311 D = A^^ = A^1^1 = A~2
312 E = B^2 = A^^2
313 F = B^3 = A^^3
314 G = A^^^ = A^1^1^1 = A~3
315 H = D^2 = B^^2 = A^^^2 = A~2^2
316 I = F^ = B^3^ = A^^3^
317 J = F^2 = B^3^2 = A^^3^2
318
319
320 SPECIFYING RANGES
321 -----------------
322
323 History traversing commands such as 'git-log' operate on a set
324 of commits, not just a single commit. To these commands,
325 specifying a single revision with the notation described in the
326 previous section means the set of commits reachable from that
327 commit, following the commit ancestry chain.
328
329 To exclude commits reachable from a commit, a prefix `{caret}`
330 notation is used. E.g. `{caret}r1 r2` means commits reachable
331 from `r2` but exclude the ones reachable from `r1`.
332
333 This set operation appears so often that there is a shorthand
334 for it. When you have two commits `r1` and `r2` (named according
335 to the syntax explained in SPECIFYING REVISIONS above), you can ask
336 for commits that are reachable from r2 excluding those that are reachable
337 from r1 by `{caret}r1 r2` and it can be written as `r1..r2`.
338
339 A similar notation `r1\...r2` is called symmetric difference
340 of `r1` and `r2` and is defined as
341 `r1 r2 --not $(git merge-base --all r1 r2)`.
342 It is the set of commits that are reachable from either one of
343 `r1` or `r2` but not from both.
344
345 Two other shorthands for naming a set that is formed by a commit
346 and its parent commits exist. The `r1{caret}@` notation means all
347 parents of `r1`. `r1{caret}!` includes commit `r1` but excludes
348 all of its parents.
349
350 Here are a handful of examples:
351
352 D G H D
353 D F G H I J D F
354 ^G D H D
355 ^D B E I J F B
356 B...C G H D E B C
357 ^D B C E I J F B C
358 C^@ I J F
359 F^! D G H D F
360
361 PARSEOPT
362 --------
363
364 In `--parseopt` mode, 'git-rev-parse' helps massaging options to bring to shell
365 scripts the same facilities C builtins have. It works as an option normalizer
366 (e.g. splits single switches aggregate values), a bit like `getopt(1)` does.
367
368 It takes on the standard input the specification of the options to parse and
369 understand, and echoes on the standard output a line suitable for `sh(1)` `eval`
370 to replace the arguments with normalized ones. In case of error, it outputs
371 usage on the standard error stream, and exits with code 129.
372
373 Input Format
374 ~~~~~~~~~~~~
375
376 'git-rev-parse --parseopt' input format is fully text based. It has two parts,
377 separated by a line that contains only `--`. The lines before the separator
378 (should be more than one) are used for the usage.
379 The lines after the separator describe the options.
380
381 Each line of options has this format:
382
383 ------------
384 <opt_spec><flags>* SP+ help LF
385 ------------
386
387 `<opt_spec>`::
388 its format is the short option character, then the long option name
389 separated by a comma. Both parts are not required, though at least one
390 is necessary. `h,help`, `dry-run` and `f` are all three correct
391 `<opt_spec>`.
392
393 `<flags>`::
394 `<flags>` are of `*`, `=`, `?` or `!`.
395 * Use `=` if the option takes an argument.
396
397 * Use `?` to mean that the option is optional (though its use is discouraged).
398
399 * Use `*` to mean that this option should not be listed in the usage
400 generated for the `-h` argument. It's shown for `--help-all` as
401 documented in linkgit:gitcli[7].
402
403 * Use `!` to not make the corresponding negated long option available.
404
405 The remainder of the line, after stripping the spaces, is used
406 as the help associated to the option.
407
408 Blank lines are ignored, and lines that don't match this specification are used
409 as option group headers (start the line with a space to create such
410 lines on purpose).
411
412 Example
413 ~~~~~~~
414
415 ------------
416 OPTS_SPEC="\
417 some-command [options] <args>...
418
419 some-command does foo and bar!
420 --
421 h,help show the help
422
423 foo some nifty option --foo
424 bar= some cool option --bar with an argument
425
426 An option group Header
427 C? option C with an optional argument"
428
429 eval `echo "$OPTS_SPEC" | git rev-parse --parseopt -- "$@" || echo exit $?`
430 ------------
431
432 SQ-QUOTE
433 --------
434
435 In `--sq-quote` mode, 'git-rev-parse' echoes on the standard output a
436 single line suitable for `sh(1)` `eval`. This line is made by
437 normalizing the arguments following `--sq-quote`. Nothing other than
438 quoting the arguments is done.
439
440 If you want command input to still be interpreted as usual by
441 'git-rev-parse' before the output is shell quoted, see the `--sq`
442 option.
443
444 Example
445 ~~~~~~~
446
447 ------------
448 $ cat >your-git-script.sh <<\EOF
449 #!/bin/sh
450 args=$(git rev-parse --sq-quote "$@") # quote user-supplied arguments
451 command="git frotz -n24 $args" # and use it inside a handcrafted
452 # command line
453 eval "$command"
454 EOF
455
456 $ sh your-git-script.sh "a b'c"
457 ------------
458
459 EXAMPLES
460 --------
461
462 * Print the object name of the current commit:
463 +
464 ------------
465 $ git rev-parse --verify HEAD
466 ------------
467
468 * Print the commit object name from the revision in the $REV shell variable:
469 +
470 ------------
471 $ git rev-parse --verify $REV
472 ------------
473 +
474 This will error out if $REV is empty or not a valid revision.
475
476 * Same as above:
477 +
478 ------------
479 $ git rev-parse --default master --verify $REV
480 ------------
481 +
482 but if $REV is empty, the commit object name from master will be printed.
483
484
485 Author
486 ------
487 Written by Linus Torvalds <torvalds@osdl.org> .
488 Junio C Hamano <gitster@pobox.com> and Pierre Habouzit <madcoder@debian.org>
489
490 Documentation
491 --------------
492 Documentation by Junio C Hamano and the git-list <git@vger.kernel.org>.
493
494 GIT
495 ---
496 Part of the linkgit:git[1] suite