Documentation / git-tag.txton commit Merge branch 'sb/committer' (b66ae79)
   1git-tag(1)
   2==========
   3
   4NAME
   5----
   6git-tag - Create, list, delete or verify a tag object signed with GPG
   7
   8
   9SYNOPSIS
  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
  17DESCRIPTION
  18-----------
  19Adds a 'tag' reference in `.git/refs/tags/`
  20
  21Unless `-f` is given, the tag must not yet exist in
  22`.git/refs/tags/` directory.
  23
  24If one of `-a`, `-s`, or `-u <key-id>` is passed, the command
  25creates 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
  27in the tag message.
  28
  29If `-m <msg>` or `-F <file>` is given and `-a`, `-s`, and `-u <key-id>`
  30are absent, `-a` is implied.
  31
  32Otherwise just the SHA1 object name of the commit object is
  33written (i.e. a lightweight tag).
  34
  35A GnuPG signed tag object will be created when `-s` or `-u
  36<key-id>` is used.  When `-u <key-id>` is not used, the
  37committer identity for the current user is used to find the
  38GnuPG key for signing.
  39
  40OPTIONS
  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
  83CONFIGURATION
  84-------------
  85By default, git-tag in sign-with-default mode (-s) will use your
  86committer identity (of the form "Your Name <your@email.address>") to
  87find a key.  If you want to use a different default key, you can specify
  88it in the repository configuration as follows:
  89
  90-------------------------------------
  91[user]
  92    signingkey = <gpg-key-id>
  93-------------------------------------
  94
  95
  96DISCUSSION
  97----------
  98
  99On Re-tagging
 100~~~~~~~~~~~~~
 101
 102What should you do when you tag a wrong commit and you would
 103want to re-tag?
 104
 105If you never pushed anything out, just re-tag it. Use "-f" to
 106replace the old one. And you're done.
 107
 108But if you have pushed things out (or others could just read
 109your repository directly), then others will have already seen
 110the old tag. In that case you can do one of two things:
 111
 112. The sane thing.
 113Just admit you screwed up, and use a different name. Others have
 114already seen one tag-name, and if you keep the same name, you
 115may be in the situation that two people both have "version X",
 116but they actually have 'different' "X"'s.  So just call it "X.1"
 117and be done with it.
 118
 119. The insane thing.
 120You really want to call the new version "X" too, 'even though'
 121others have already seen the old one. So just use "git tag -f"
 122again, as if you hadn't already published the old one.
 123
 124However, Git does *not* (and it should not) change tags behind
 125users back. So if somebody already got the old tag, doing a "git
 126pull" on your tree shouldn't just make them overwrite the old
 127one.
 128
 129If somebody got a release tag from you, you cannot just change
 130the tag for them by updating your own one. This is a big
 131security issue, in that people MUST be able to trust their
 132tag-names.  If you really want to do the insane thing, you need
 133to just fess up to it, and tell people that you messed up. You
 134can do that by making a very public announcement saying:
 135
 136------------
 137Ok, I messed up, and I pushed out an earlier version tagged as X. I
 138then fixed something, and retagged the *fixed* tree as X again.
 139
 140If you got the wrong tag, and want the new one, please delete
 141the old one and fetch the new one by doing:
 142
 143        git tag -d X
 144        git fetch origin tag X
 145
 146to get my updated tag.
 147
 148You can test which tag you have by doing
 149
 150        git rev-parse X
 151
 152which should return 0123456789abcdef.. if you have the new version.
 153
 154Sorry for inconvenience.
 155------------
 156
 157Does this seem a bit complicated?  It *should* be. There is no
 158way that it would be correct to just "fix" it behind peoples
 159backs. People need to know that their tags might have been
 160changed.
 161
 162
 163On Automatic following
 164~~~~~~~~~~~~~~~~~~~~~~
 165
 166If you are following somebody else's tree, you are most likely
 167using tracking branches (`refs/heads/origin` in traditional
 168layout, or `refs/remotes/origin/master` in the separate-remote
 169layout).  You usually want the tags from the other end.
 170
 171On the other hand, if you are fetching because you would want a
 172one-shot merge from somebody else, you typically do not want to
 173get tags from there.  This happens more often for people near
 174the toplevel but not limited to them.  Mere mortals when pulling
 175from each other do not necessarily want to automatically get
 176private anchor point tags from the other person.
 177
 178You would notice "please pull" messages on the mailing list says
 179repo URL and branch name alone.  This is designed to be easily
 180cut&pasted to "git fetch" command line:
 181
 182------------
 183Linus, please pull from
 184
 185        git://git..../proj.git master
 186
 187to get the following updates...
 188------------
 189
 190becomes:
 191
 192------------
 193$ git pull git://git..../proj.git master
 194------------
 195
 196In such a case, you do not want to automatically follow other's
 197tags.
 198
 199One important aspect of git is it is distributed, and being
 200distributed largely means there is no inherent "upstream" or
 201"downstream" in the system.  On the face of it, the above
 202example might seem to indicate that the tag namespace is owned
 203by upper echelon of people and tags only flow downwards, but
 204that is not the case.  It only shows that the usage pattern
 205determines who are interested in whose tags.
 206
 207A one-shot pull is a sign that a commit history is now crossing
 208the boundary between one circle of people (e.g. "people who are
 209primarily interested in networking part of the kernel") who may
 210have their own set of tags (e.g. "this is the third release
 211candidate from the networking group to be proposed for general
 212consumption with 2.6.21 release") to another circle of people
 213(e.g. "people who integrate various subsystem improvements").
 214The latter are usually not interested in the detailed tags used
 215internally in the former group (that is what "internal" means).
 216That is why it is desirable not to follow tags automatically in
 217this case.
 218
 219It may well be that among networking people, they may want to
 220exchange the tags internal to their group, but in that workflow
 221they are most likely tracking with each other's progress by
 222having tracking branches.  Again, the heuristic to automatically
 223follow such tags is a good thing.
 224
 225
 226On Backdating Tags
 227~~~~~~~~~~~~~~~~~~
 228
 229If you have imported some changes from another VCS and would like
 230to add tags for major releases of your work, it is useful to be able
 231to specify the date to embed inside of the tag object.  The data in
 232the tag object affects, for example, the ordering of tags in the
 233gitweb interface.
 234
 235To set the date used in future tag objects, set the environment
 236variable GIT_COMMITTER_DATE to one or more of the date and time.  The
 237date and time can be specified in a number of ways; the most common
 238is "YYYY-MM-DD HH:MM".
 239
 240An example follows.
 241
 242------------
 243$ GIT_COMMITTER_DATE="2006-10-02 10:31" git tag -s v1.0.1
 244------------
 245
 246
 247Author
 248------
 249Written by Linus Torvalds <torvalds@osdl.org>,
 250Junio C Hamano <junkio@cox.net> and Chris Wright <chrisw@osdl.org>.
 251
 252Documentation
 253--------------
 254Documentation by David Greaves, Junio C Hamano and the git-list <git@vger.kernel.org>.
 255
 256GIT
 257---
 258Part of the linkgit:git[7] suite