Documentation / git-tag.txton commit Merge branch 'ph/parseopt-sh' (9f4c4eb)
   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
  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
  37OPTIONS
  38-------
  39-a::
  40        Make an unsigned, annotated tag object
  41
  42-s::
  43        Make a GPG-signed tag, using the default e-mail address's key
  44
  45-u <key-id>::
  46        Make a GPG-signed tag, using the given key
  47
  48-f::
  49        Replace an existing tag with the given name (instead of failing)
  50
  51-d::
  52        Delete existing tags with the given names.
  53
  54-v::
  55        Verify the gpg signature of the given tag names.
  56
  57-n <num>::
  58        <num> specifies how many lines from the annotation, if any,
  59        are printed when using -l.
  60        The default is not to print any annotation lines.
  61        If no number is given to `-n`, only the first line is printed.
  62
  63-l <pattern>::
  64        List tags with names that match the given pattern (or all if no pattern is given).
  65        Typing "git tag" without arguments, also lists all tags.
  66
  67-m <msg>::
  68        Use the given tag message (instead of prompting)
  69
  70-F <file>::
  71        Take the tag message from the given file.  Use '-' to
  72        read the message from the standard input.
  73
  74CONFIGURATION
  75-------------
  76By default, git-tag in sign-with-default mode (-s) will use your
  77committer identity (of the form "Your Name <your@email.address>") to
  78find a key.  If you want to use a different default key, you can specify
  79it in the repository configuration as follows:
  80
  81-------------------------------------
  82[user]
  83    signingkey = <gpg-key-id>
  84-------------------------------------
  85
  86
  87DISCUSSION
  88----------
  89
  90On Re-tagging
  91~~~~~~~~~~~~~
  92
  93What should you do when you tag a wrong commit and you would
  94want to re-tag?
  95
  96If you never pushed anything out, just re-tag it. Use "-f" to
  97replace the old one. And you're done.
  98
  99But if you have pushed things out (or others could just read
 100your repository directly), then others will have already seen
 101the old tag. In that case you can do one of two things:
 102
 103. The sane thing.
 104Just admit you screwed up, and use a different name. Others have
 105already seen one tag-name, and if you keep the same name, you
 106may be in the situation that two people both have "version X",
 107but they actually have 'different' "X"'s.  So just call it "X.1"
 108and be done with it.
 109
 110. The insane thing.
 111You really want to call the new version "X" too, 'even though'
 112others have already seen the old one. So just use "git tag -f"
 113again, as if you hadn't already published the old one.
 114
 115However, Git does *not* (and it should not) change tags behind
 116users back. So if somebody already got the old tag, doing a "git
 117pull" on your tree shouldn't just make them overwrite the old
 118one.
 119
 120If somebody got a release tag from you, you cannot just change
 121the tag for them by updating your own one. This is a big
 122security issue, in that people MUST be able to trust their
 123tag-names.  If you really want to do the insane thing, you need
 124to just fess up to it, and tell people that you messed up. You
 125can do that by making a very public announcement saying:
 126
 127------------
 128Ok, I messed up, and I pushed out an earlier version tagged as X. I
 129then fixed something, and retagged the *fixed* tree as X again.
 130
 131If you got the wrong tag, and want the new one, please delete
 132the old one and fetch the new one by doing:
 133
 134        git tag -d X
 135        git fetch origin tag X
 136
 137to get my updated tag.
 138
 139You can test which tag you have by doing
 140
 141        git rev-parse X
 142
 143which should return 0123456789abcdef.. if you have the new version.
 144
 145Sorry for inconvenience.
 146------------
 147
 148Does this seem a bit complicated?  It *should* be. There is no
 149way that it would be correct to just "fix" it behind peoples
 150backs. People need to know that their tags might have been
 151changed.
 152
 153
 154On Automatic following
 155~~~~~~~~~~~~~~~~~~~~~~
 156
 157If you are following somebody else's tree, you are most likely
 158using tracking branches (`refs/heads/origin` in traditional
 159layout, or `refs/remotes/origin/master` in the separate-remote
 160layout).  You usually want the tags from the other end.
 161
 162On the other hand, if you are fetching because you would want a
 163one-shot merge from somebody else, you typically do not want to
 164get tags from there.  This happens more often for people near
 165the toplevel but not limited to them.  Mere mortals when pulling
 166from each other do not necessarily want to automatically get
 167private anchor point tags from the other person.
 168
 169You would notice "please pull" messages on the mailing list says
 170repo URL and branch name alone.  This is designed to be easily
 171cut&pasted to "git fetch" command line:
 172
 173------------
 174Linus, please pull from
 175
 176        git://git..../proj.git master
 177
 178to get the following updates...
 179------------
 180
 181becomes:
 182
 183------------
 184$ git pull git://git..../proj.git master
 185------------
 186
 187In such a case, you do not want to automatically follow other's
 188tags.
 189
 190One important aspect of git is it is distributed, and being
 191distributed largely means there is no inherent "upstream" or
 192"downstream" in the system.  On the face of it, the above
 193example might seem to indicate that the tag namespace is owned
 194by upper echelon of people and tags only flow downwards, but
 195that is not the case.  It only shows that the usage pattern
 196determines who are interested in whose tags.
 197
 198A one-shot pull is a sign that a commit history is now crossing
 199the boundary between one circle of people (e.g. "people who are
 200primarily interested in networking part of the kernel") who may
 201have their own set of tags (e.g. "this is the third release
 202candidate from the networking group to be proposed for general
 203consumption with 2.6.21 release") to another circle of people
 204(e.g. "people who integrate various subsystem improvements").
 205The latter are usually not interested in the detailed tags used
 206internally in the former group (that is what "internal" means).
 207That is why it is desirable not to follow tags automatically in
 208this case.
 209
 210It may well be that among networking people, they may want to
 211exchange the tags internal to their group, but in that workflow
 212they are most likely tracking with each other's progress by
 213having tracking branches.  Again, the heuristic to automatically
 214follow such tags is a good thing.
 215
 216
 217On Backdating Tags
 218~~~~~~~~~~~~~~~~~~
 219
 220If you have imported some changes from another VCS and would like
 221to add tags for major releases of your work, it is useful to be able
 222to specify the date to embed inside of the tag object.  The data in
 223the tag object affects, for example, the ordering of tags in the
 224gitweb interface.
 225
 226To set the date used in future tag objects, set the environment
 227variable GIT_AUTHOR_DATE to one or more of the date and time.  The
 228date and time can be specified in a number of ways; the most common
 229is "YYYY-MM-DD HH:MM".
 230
 231An example follows.
 232
 233------------
 234$ GIT_AUTHOR_DATE="2006-10-02 10:31" git tag -s v1.0.1
 235------------
 236
 237
 238Author
 239------
 240Written by Linus Torvalds <torvalds@osdl.org>,
 241Junio C Hamano <junkio@cox.net> and Chris Wright <chrisw@osdl.org>.
 242
 243Documentation
 244--------------
 245Documentation by David Greaves, Junio C Hamano and the git-list <git@vger.kernel.org>.
 246
 247GIT
 248---
 249Part of the gitlink:git[7] suite