Documentation / git-tag.txton commit Merge branch 'mm/tag' (6abd0fb)
   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>` is given, an editor is started for the user to type
  27in the tag message.
  28
  29Otherwise just the SHA1 object name of the commit object is
  30written (i.e. a lightweight tag).
  31
  32A GnuPG signed tag object will be created when `-s` or `-u
  33<key-id>` is used.  When `-u <key-id>` is not used, the
  34committer identity for the current user is used to find the
  35GnuPG key for signing.
  36
  37`-d <tag>` deletes the tag.
  38
  39`-v <tag>` verifies the gpg signature of the tag.
  40
  41`-l <pattern>` lists tags with names that match the given pattern
  42(or all if no pattern is given).
  43
  44OPTIONS
  45-------
  46-a::
  47        Make an unsigned, annotated tag object
  48
  49-s::
  50        Make a GPG-signed tag, using the default e-mail address's key
  51
  52-u <key-id>::
  53        Make a GPG-signed tag, using the given key
  54
  55-f::
  56        Replace an existing tag with the given name (instead of failing)
  57
  58-d::
  59        Delete existing tags with the given names.
  60
  61-v::
  62        Verify the gpg signature of given the tag
  63
  64-n <num>::
  65        <num> specifies how many lines from the annotation, if any,
  66        are printed when using -l.
  67        The default is not to print any annotation lines.
  68
  69-l <pattern>::
  70        List tags with names that match the given pattern (or all if no pattern is given).
  71
  72-m <msg>::
  73        Use the given tag message (instead of prompting)
  74
  75-F <file>::
  76        Take the tag message from the given file.  Use '-' to
  77        read the message from the standard input.
  78
  79CONFIGURATION
  80-------------
  81By default, git-tag in sign-with-default mode (-s) will use your
  82committer identity (of the form "Your Name <your@email.address>") to
  83find a key.  If you want to use a different default key, you can specify
  84it in the repository configuration as follows:
  85
  86-------------------------------------
  87[user]
  88    signingkey = <gpg-key-id>
  89-------------------------------------
  90
  91
  92DISCUSSION
  93----------
  94
  95On Re-tagging
  96~~~~~~~~~~~~~
  97
  98What should you do when you tag a wrong commit and you would
  99want to re-tag?
 100
 101If you never pushed anything out, just re-tag it. Use "-f" to
 102replace the old one. And you're done.
 103
 104But if you have pushed things out (or others could just read
 105your repository directly), then others will have already seen
 106the old tag. In that case you can do one of two things:
 107
 108. The sane thing.
 109Just admit you screwed up, and use a different name. Others have
 110already seen one tag-name, and if you keep the same name, you
 111may be in the situation that two people both have "version X",
 112but they actually have 'different' "X"'s.  So just call it "X.1"
 113and be done with it.
 114
 115. The insane thing.
 116You really want to call the new version "X" too, 'even though'
 117others have already seen the old one. So just use "git tag -f"
 118again, as if you hadn't already published the old one.
 119
 120However, Git does *not* (and it should not)change tags behind
 121users back. So if somebody already got the old tag, doing a "git
 122pull" on your tree shouldn't just make them overwrite the old
 123one.
 124
 125If somebody got a release tag from you, you cannot just change
 126the tag for them by updating your own one. This is a big
 127security issue, in that people MUST be able to trust their
 128tag-names.  If you really want to do the insane thing, you need
 129to just fess up to it, and tell people that you messed up. You
 130can do that by making a very public announcement saying:
 131
 132------------
 133Ok, I messed up, and I pushed out an earlier version tagged as X. I
 134then fixed something, and retagged the *fixed* tree as X again.
 135
 136If you got the wrong tag, and want the new one, please delete
 137the old one and fetch the new one by doing:
 138
 139        git tag -d X
 140        git fetch origin tag X
 141
 142to get my updated tag.
 143
 144You can test which tag you have by doing
 145
 146        git rev-parse X
 147
 148which should return 0123456789abcdef.. if you have the new version.
 149
 150Sorry for inconvenience.
 151------------
 152
 153Does this seem a bit complicated?  It *should* be. There is no
 154way that it would be correct to just "fix" it behind peoples
 155backs. People need to know that their tags might have been
 156changed.
 157
 158
 159On Automatic following
 160~~~~~~~~~~~~~~~~~~~~~~
 161
 162If you are following somebody else's tree, you are most likely
 163using tracking branches (`refs/heads/origin` in traditional
 164layout, or `refs/remotes/origin/master` in the separate-remote
 165layout).  You usually want the tags from the other end.
 166
 167On the other hand, if you are fetching because you would want a
 168one-shot merge from somebody else, you typically do not want to
 169get tags from there.  This happens more often for people near
 170the toplevel but not limited to them.  Mere mortals when pulling
 171from each other do not necessarily want to automatically get
 172private anchor point tags from the other person.
 173
 174You would notice "please pull" messages on the mailing list says
 175repo URL and branch name alone.  This is designed to be easily
 176cut&pasted to "git fetch" command line:
 177
 178------------
 179Linus, please pull from
 180
 181        git://git..../proj.git master
 182
 183to get the following updates...
 184------------
 185
 186becomes:
 187
 188------------
 189$ git pull git://git..../proj.git master
 190------------
 191
 192In such a case, you do not want to automatically follow other's
 193tags.
 194
 195One important aspect of git is it is distributed, and being
 196distributed largely means there is no inherent "upstream" or
 197"downstream" in the system.  On the face of it, the above
 198example might seem to indicate that the tag namespace is owned
 199by upper echelon of people and tags only flow downwards, but
 200that is not the case.  It only shows that the usage pattern
 201determines who are interested in whose tags.
 202
 203A one-shot pull is a sign that a commit history is now crossing
 204the boundary between one circle of people (e.g. "people who are
 205primarily interested in networking part of the kernel") who may
 206have their own set of tags (e.g. "this is the third release
 207candidate from the networking group to be proposed for general
 208consumption with 2.6.21 release") to another circle of people
 209(e.g. "people who integrate various subsystem improvements").
 210The latter are usually not interested in the detailed tags used
 211internally in the former group (that is what "internal" means).
 212That is why it is desirable not to follow tags automatically in
 213this case.
 214
 215It may well be that among networking people, they may want to
 216exchange the tags internal to their group, but in that workflow
 217they are most likely tracking with each other's progress by
 218having tracking branches.  Again, the heuristic to automatically
 219follow such tags is a good thing.
 220
 221
 222Author
 223------
 224Written by Linus Torvalds <torvalds@osdl.org>,
 225Junio C Hamano <junkio@cox.net> and Chris Wright <chrisw@osdl.org>.
 226
 227Documentation
 228--------------
 229Documentation by David Greaves, Junio C Hamano and the git-list <git@vger.kernel.org>.
 230
 231GIT
 232---
 233Part of the gitlink:git[7] suite