Documentation / git-tag.txton commit am doc: add a pointer to relevant hooks (0e3d40c)
   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>]
  13        <tagname> [<commit> | <object>]
  14'git tag' -d <tagname>...
  15'git tag' [-n[<num>]] -l [--contains <commit>] [--points-at <object>]
  16        [--column[=<options>] | --no-column] [<pattern>...]
  17        [<pattern>...]
  18'git tag' -v <tagname>...
  19
  20DESCRIPTION
  21-----------
  22
  23Add a tag reference in `refs/tags/`, unless `-d/-l/-v` is given
  24to delete, list or verify tags.
  25
  26Unless `-f` is given, the named tag must not yet exist.
  27
  28If one of `-a`, `-s`, or `-u <key-id>` is passed, the command
  29creates a 'tag' object, and requires a tag message.  Unless
  30`-m <msg>` or `-F <file>` is given, an editor is started for the user to type
  31in the tag message.
  32
  33If `-m <msg>` or `-F <file>` is given and `-a`, `-s`, and `-u <key-id>`
  34are absent, `-a` is implied.
  35
  36Otherwise just a tag reference for the SHA-1 object name of the commit object is
  37created (i.e. a lightweight tag).
  38
  39A GnuPG signed tag object will be created when `-s` or `-u
  40<key-id>` is used.  When `-u <key-id>` is not used, the
  41committer identity for the current user is used to find the
  42GnuPG key for signing.  The configuration variable `gpg.program`
  43is used to specify custom GnuPG binary.
  44
  45Tag objects (created with `-a`, `s`, or `-u`) are called "annotated"
  46tags; they contain a creation date, the tagger name and e-mail, a
  47tagging message, and an optional GnuPG signature. Whereas a
  48"lightweight" tag is simply a name for an object (usually a commit
  49object).
  50
  51Annotated tags are meant for release while lightweight tags are meant
  52for private or temporary object labels. For this reason, some git
  53commands for naming objects (like `git describe`) will ignore
  54lightweight tags by default.
  55
  56
  57OPTIONS
  58-------
  59-a::
  60--annotate::
  61        Make an unsigned, annotated tag object
  62
  63-s::
  64--sign::
  65        Make a GPG-signed tag, using the default e-mail address's key.
  66
  67-u <key-id>::
  68--local-user=<key-id>::
  69        Make a GPG-signed tag, using the given key.
  70
  71-f::
  72--force::
  73        Replace an existing tag with the given name (instead of failing)
  74
  75-d::
  76--delete::
  77        Delete existing tags with the given names.
  78
  79-v::
  80--verify::
  81        Verify the gpg signature of the given tag names.
  82
  83-n<num>::
  84        <num> specifies how many lines from the annotation, if any,
  85        are printed when using -l.
  86        The default is not to print any annotation lines.
  87        If no number is given to `-n`, only the first line is printed.
  88        If the tag is not annotated, the commit message is displayed instead.
  89
  90-l <pattern>::
  91--list <pattern>::
  92        List tags with names that match the given pattern (or all if no
  93        pattern is given).  Running "git tag" without arguments also
  94        lists all tags. The pattern is a shell wildcard (i.e., matched
  95        using fnmatch(3)).  Multiple patterns may be given; if any of
  96        them matches, the tag is shown.
  97
  98--column[=<options>]::
  99--no-column::
 100        Display tag listing in columns. See configuration variable
 101        column.tag for option syntax.`--column` and `--no-column`
 102        without options are equivalent to 'always' and 'never' respectively.
 103+
 104This option is only applicable when listing tags without annotation lines.
 105
 106--contains [<commit>]::
 107        Only list tags which contain the specified commit (HEAD if not
 108        specified).
 109
 110--points-at <object>::
 111        Only list tags of the given object.
 112
 113-m <msg>::
 114--message=<msg>::
 115        Use the given tag message (instead of prompting).
 116        If multiple `-m` options are given, their values are
 117        concatenated as separate paragraphs.
 118        Implies `-a` if none of `-a`, `-s`, or `-u <key-id>`
 119        is given.
 120
 121-F <file>::
 122--file=<file>::
 123        Take the tag message from the given file.  Use '-' to
 124        read the message from the standard input.
 125        Implies `-a` if none of `-a`, `-s`, or `-u <key-id>`
 126        is given.
 127
 128--cleanup=<mode>::
 129        This option sets how the tag message is cleaned up.
 130        The  '<mode>' can be one of 'verbatim', 'whitespace' and 'strip'.  The
 131        'strip' mode is default. The 'verbatim' mode does not change message at
 132        all, 'whitespace' removes just leading/trailing whitespace lines and
 133        'strip' removes both whitespace and commentary.
 134
 135<tagname>::
 136        The name of the tag to create, delete, or describe.
 137        The new tag name must pass all checks defined by
 138        linkgit:git-check-ref-format[1].  Some of these checks
 139        may restrict the characters allowed in a tag name.
 140
 141<commit>::
 142<object>::
 143        The object that the new tag will refer to, usually a commit.
 144        Defaults to HEAD.
 145
 146
 147CONFIGURATION
 148-------------
 149By default, 'git tag' in sign-with-default mode (-s) will use your
 150committer identity (of the form "Your Name <\your@email.address>") to
 151find a key.  If you want to use a different default key, you can specify
 152it in the repository configuration as follows:
 153
 154-------------------------------------
 155[user]
 156    signingkey = <gpg-key-id>
 157-------------------------------------
 158
 159
 160DISCUSSION
 161----------
 162
 163On Re-tagging
 164~~~~~~~~~~~~~
 165
 166What should you do when you tag a wrong commit and you would
 167want to re-tag?
 168
 169If you never pushed anything out, just re-tag it. Use "-f" to
 170replace the old one. And you're done.
 171
 172But if you have pushed things out (or others could just read
 173your repository directly), then others will have already seen
 174the old tag. In that case you can do one of two things:
 175
 176. The sane thing.
 177Just admit you screwed up, and use a different name. Others have
 178already seen one tag-name, and if you keep the same name, you
 179may be in the situation that two people both have "version X",
 180but they actually have 'different' "X"'s.  So just call it "X.1"
 181and be done with it.
 182
 183. The insane thing.
 184You really want to call the new version "X" too, 'even though'
 185others have already seen the old one. So just use 'git tag -f'
 186again, as if you hadn't already published the old one.
 187
 188However, Git does *not* (and it should not) change tags behind
 189users back. So if somebody already got the old tag, doing a
 190'git pull' on your tree shouldn't just make them overwrite the old
 191one.
 192
 193If somebody got a release tag from you, you cannot just change
 194the tag for them by updating your own one. This is a big
 195security issue, in that people MUST be able to trust their
 196tag-names.  If you really want to do the insane thing, you need
 197to just fess up to it, and tell people that you messed up. You
 198can do that by making a very public announcement saying:
 199
 200------------
 201Ok, I messed up, and I pushed out an earlier version tagged as X. I
 202then fixed something, and retagged the *fixed* tree as X again.
 203
 204If you got the wrong tag, and want the new one, please delete
 205the old one and fetch the new one by doing:
 206
 207        git tag -d X
 208        git fetch origin tag X
 209
 210to get my updated tag.
 211
 212You can test which tag you have by doing
 213
 214        git rev-parse X
 215
 216which should return 0123456789abcdef.. if you have the new version.
 217
 218Sorry for the inconvenience.
 219------------
 220
 221Does this seem a bit complicated?  It *should* be. There is no
 222way that it would be correct to just "fix" it automatically.
 223People need to know that their tags might have been changed.
 224
 225
 226On Automatic following
 227~~~~~~~~~~~~~~~~~~~~~~
 228
 229If you are following somebody else's tree, you are most likely
 230using remote-tracking branches (`refs/heads/origin` in traditional
 231layout, or `refs/remotes/origin/master` in the separate-remote
 232layout).  You usually want the tags from the other end.
 233
 234On the other hand, if you are fetching because you would want a
 235one-shot merge from somebody else, you typically do not want to
 236get tags from there.  This happens more often for people near
 237the toplevel but not limited to them.  Mere mortals when pulling
 238from each other do not necessarily want to automatically get
 239private anchor point tags from the other person.
 240
 241Often, "please pull" messages on the mailing list just provide
 242two pieces of information: a repo URL and a branch name; this
 243is designed to be easily cut&pasted at the end of a 'git fetch'
 244command line:
 245
 246------------
 247Linus, please pull from
 248
 249        git://git..../proj.git master
 250
 251to get the following updates...
 252------------
 253
 254becomes:
 255
 256------------
 257$ git pull git://git..../proj.git master
 258------------
 259
 260In such a case, you do not want to automatically follow the other
 261person's tags.
 262
 263One important aspect of Git is its distributed nature, which
 264largely means there is no inherent "upstream" or
 265"downstream" in the system.  On the face of it, the above
 266example might seem to indicate that the tag namespace is owned
 267by the upper echelon of people and that tags only flow downwards, but
 268that is not the case.  It only shows that the usage pattern
 269determines who are interested in whose tags.
 270
 271A one-shot pull is a sign that a commit history is now crossing
 272the boundary between one circle of people (e.g. "people who are
 273primarily interested in the networking part of the kernel") who may
 274have their own set of tags (e.g. "this is the third release
 275candidate from the networking group to be proposed for general
 276consumption with 2.6.21 release") to another circle of people
 277(e.g. "people who integrate various subsystem improvements").
 278The latter are usually not interested in the detailed tags used
 279internally in the former group (that is what "internal" means).
 280That is why it is desirable not to follow tags automatically in
 281this case.
 282
 283It may well be that among networking people, they may want to
 284exchange the tags internal to their group, but in that workflow
 285they are most likely tracking each other's progress by
 286having remote-tracking branches.  Again, the heuristic to automatically
 287follow such tags is a good thing.
 288
 289
 290On Backdating Tags
 291~~~~~~~~~~~~~~~~~~
 292
 293If you have imported some changes from another VCS and would like
 294to add tags for major releases of your work, it is useful to be able
 295to specify the date to embed inside of the tag object; such data in
 296the tag object affects, for example, the ordering of tags in the
 297gitweb interface.
 298
 299To set the date used in future tag objects, set the environment
 300variable GIT_COMMITTER_DATE (see the later discussion of possible
 301values; the most common form is "YYYY-MM-DD HH:MM").
 302
 303For example:
 304
 305------------
 306$ GIT_COMMITTER_DATE="2006-10-02 10:31" git tag -s v1.0.1
 307------------
 308
 309include::date-formats.txt[]
 310
 311SEE ALSO
 312--------
 313linkgit:git-check-ref-format[1].
 314
 315GIT
 316---
 317Part of the linkgit:git[1] suite