Make git-add behave more sensibly in a case-insensitive environment
[git/git.git] / Documentation / git-tag.txt
1 git-tag(1)
2 ==========
3
4 NAME
5 ----
6 git-tag - Create, list, delete or verify a tag object signed with GPG
7
8
9 SYNOPSIS
10 --------
11 [verse]
12 'git-tag' [-a | -s | -u <key-id>] [-f] [-m <msg> | -F <file>] <name> [<head>]
13 'git-tag' -d <name>...
14 'git-tag' [-n [<num>]] -l [<pattern>]
15 'git-tag' -v <name>...
16
17 DESCRIPTION
18 -----------
19 Adds a 'tag' reference in `.git/refs/tags/`
20
21 Unless `-f` is given, the tag must not yet exist in
22 `.git/refs/tags/` directory.
23
24 If one of `-a`, `-s`, or `-u <key-id>` is passed, the command
25 creates a 'tag' object, and requires the tag message. Unless
26 `-m <msg>` or `-F <file>` is given, an editor is started for the user to type
27 in the tag message.
28
29 If `-m <msg>` or `-F <file>` is given and `-a`, `-s`, and `-u <key-id>`
30 are absent, `-a` is implied.
31
32 Otherwise just the SHA1 object name of the commit object is
33 written (i.e. a lightweight tag).
34
35 A GnuPG signed tag object will be created when `-s` or `-u
36 <key-id>` is used. When `-u <key-id>` is not used, the
37 committer identity for the current user is used to find the
38 GnuPG key for signing.
39
40 OPTIONS
41 -------
42 -a::
43 Make an unsigned, annotated tag object
44
45 -s::
46 Make a GPG-signed tag, using the default e-mail address's key
47
48 -u <key-id>::
49 Make a GPG-signed tag, using the given key
50
51 -f::
52 Replace an existing tag with the given name (instead of failing)
53
54 -d::
55 Delete existing tags with the given names.
56
57 -v::
58 Verify the gpg signature of the given tag names.
59
60 -n <num>::
61 <num> specifies how many lines from the annotation, if any,
62 are printed when using -l.
63 The default is not to print any annotation lines.
64 If no number is given to `-n`, only the first line is printed.
65
66 -l <pattern>::
67 List tags with names that match the given pattern (or all if no pattern is given).
68 Typing "git tag" without arguments, also lists all tags.
69
70 -m <msg>::
71 Use the given tag message (instead of prompting).
72 If multiple `-m` options are given, there values are
73 concatenated as separate paragraphs.
74 Implies `-a` if none of `-a`, `-s`, or `-u <key-id>`
75 is given.
76
77 -F <file>::
78 Take the tag message from the given file. Use '-' to
79 read the message from the standard input.
80 Implies `-a` if none of `-a`, `-s`, or `-u <key-id>`
81 is given.
82
83 CONFIGURATION
84 -------------
85 By default, git-tag in sign-with-default mode (-s) will use your
86 committer identity (of the form "Your Name <your@email.address>") to
87 find a key. If you want to use a different default key, you can specify
88 it in the repository configuration as follows:
89
90 -------------------------------------
91 [user]
92 signingkey = <gpg-key-id>
93 -------------------------------------
94
95
96 DISCUSSION
97 ----------
98
99 On Re-tagging
100 ~~~~~~~~~~~~~
101
102 What should you do when you tag a wrong commit and you would
103 want to re-tag?
104
105 If you never pushed anything out, just re-tag it. Use "-f" to
106 replace the old one. And you're done.
107
108 But if you have pushed things out (or others could just read
109 your repository directly), then others will have already seen
110 the old tag. In that case you can do one of two things:
111
112 . The sane thing.
113 Just admit you screwed up, and use a different name. Others have
114 already seen one tag-name, and if you keep the same name, you
115 may be in the situation that two people both have "version X",
116 but they actually have 'different' "X"'s. So just call it "X.1"
117 and be done with it.
118
119 . The insane thing.
120 You really want to call the new version "X" too, 'even though'
121 others have already seen the old one. So just use "git tag -f"
122 again, as if you hadn't already published the old one.
123
124 However, Git does *not* (and it should not) change tags behind
125 users back. So if somebody already got the old tag, doing a "git
126 pull" on your tree shouldn't just make them overwrite the old
127 one.
128
129 If somebody got a release tag from you, you cannot just change
130 the tag for them by updating your own one. This is a big
131 security issue, in that people MUST be able to trust their
132 tag-names. If you really want to do the insane thing, you need
133 to just fess up to it, and tell people that you messed up. You
134 can do that by making a very public announcement saying:
135
136 ------------
137 Ok, I messed up, and I pushed out an earlier version tagged as X. I
138 then fixed something, and retagged the *fixed* tree as X again.
139
140 If you got the wrong tag, and want the new one, please delete
141 the old one and fetch the new one by doing:
142
143 git tag -d X
144 git fetch origin tag X
145
146 to get my updated tag.
147
148 You can test which tag you have by doing
149
150 git rev-parse X
151
152 which should return 0123456789abcdef.. if you have the new version.
153
154 Sorry for inconvenience.
155 ------------
156
157 Does this seem a bit complicated? It *should* be. There is no
158 way that it would be correct to just "fix" it behind peoples
159 backs. People need to know that their tags might have been
160 changed.
161
162
163 On Automatic following
164 ~~~~~~~~~~~~~~~~~~~~~~
165
166 If you are following somebody else's tree, you are most likely
167 using tracking branches (`refs/heads/origin` in traditional
168 layout, or `refs/remotes/origin/master` in the separate-remote
169 layout). You usually want the tags from the other end.
170
171 On the other hand, if you are fetching because you would want a
172 one-shot merge from somebody else, you typically do not want to
173 get tags from there. This happens more often for people near
174 the toplevel but not limited to them. Mere mortals when pulling
175 from each other do not necessarily want to automatically get
176 private anchor point tags from the other person.
177
178 You would notice "please pull" messages on the mailing list says
179 repo URL and branch name alone. This is designed to be easily
180 cut&pasted to "git fetch" command line:
181
182 ------------
183 Linus, please pull from
184
185 git://git..../proj.git master
186
187 to get the following updates...
188 ------------
189
190 becomes:
191
192 ------------
193 $ git pull git://git..../proj.git master
194 ------------
195
196 In such a case, you do not want to automatically follow other's
197 tags.
198
199 One important aspect of git is it is distributed, and being
200 distributed largely means there is no inherent "upstream" or
201 "downstream" in the system. On the face of it, the above
202 example might seem to indicate that the tag namespace is owned
203 by upper echelon of people and tags only flow downwards, but
204 that is not the case. It only shows that the usage pattern
205 determines who are interested in whose tags.
206
207 A one-shot pull is a sign that a commit history is now crossing
208 the boundary between one circle of people (e.g. "people who are
209 primarily interested in networking part of the kernel") who may
210 have their own set of tags (e.g. "this is the third release
211 candidate from the networking group to be proposed for general
212 consumption with 2.6.21 release") to another circle of people
213 (e.g. "people who integrate various subsystem improvements").
214 The latter are usually not interested in the detailed tags used
215 internally in the former group (that is what "internal" means).
216 That is why it is desirable not to follow tags automatically in
217 this case.
218
219 It may well be that among networking people, they may want to
220 exchange the tags internal to their group, but in that workflow
221 they are most likely tracking with each other's progress by
222 having tracking branches. Again, the heuristic to automatically
223 follow such tags is a good thing.
224
225
226 On Backdating Tags
227 ~~~~~~~~~~~~~~~~~~
228
229 If you have imported some changes from another VCS and would like
230 to add tags for major releases of your work, it is useful to be able
231 to specify the date to embed inside of the tag object. The data in
232 the tag object affects, for example, the ordering of tags in the
233 gitweb interface.
234
235 To set the date used in future tag objects, set the environment
236 variable GIT_AUTHOR_DATE to one or more of the date and time. The
237 date and time can be specified in a number of ways; the most common
238 is "YYYY-MM-DD HH:MM".
239
240 An example follows.
241
242 ------------
243 $ GIT_AUTHOR_DATE="2006-10-02 10:31" git tag -s v1.0.1
244 ------------
245
246
247 Author
248 ------
249 Written by Linus Torvalds <torvalds@osdl.org>,
250 Junio C Hamano <junkio@cox.net> and Chris Wright <chrisw@osdl.org>.
251
252 Documentation
253 --------------
254 Documentation by David Greaves, Junio C Hamano and the git-list <git@vger.kernel.org>.
255
256 GIT
257 ---
258 Part of the linkgit:git[7] suite