git-tag(1)


NAME

   git-tag - Create, list, delete or verify a tag object signed with GPG

SYNOPSIS

   git tag [-a | -s | -u <keyid>] [-f] [-m <msg> | -F <file>]
           <tagname> [<commit> | <object>]
   git tag -d <tagname>...
   git tag [-n[<num>]] -l [--contains <commit>] [--points-at <object>]
           [--column[=<options>] | --no-column] [--create-reflog] [--sort=<key>]
           [--format=<format>] [--[no-]merged [<commit>]] [<pattern>...]
   git tag -v <tagname>...

DESCRIPTION

   Add a tag reference in refs/tags/, unless -d/-l/-v is given to delete,
   list or verify tags.

   Unless -f is given, the named tag must not yet exist.

   If one of -a, -s, or -u <keyid> is passed, the command creates a tag
   object, and requires a tag message. Unless -m <msg> or -F <file> is
   given, an editor is started for the user to type in the tag message.

   If -m <msg> or -F <file> is given and -a, -s, and -u <keyid> are
   absent, -a is implied.

   Otherwise just a tag reference for the SHA-1 object name of the commit
   object is created (i.e. a lightweight tag).

   A GnuPG signed tag object will be created when -s or -u <keyid> is
   used. When -u <keyid> is not used, the committer identity for the
   current user is used to find the GnuPG key for signing. The
   configuration variable gpg.program is used to specify custom GnuPG
   binary.

   Tag objects (created with -a, -s, or -u) are called "annotated" tags;
   they contain a creation date, the tagger name and e-mail, a tagging
   message, and an optional GnuPG signature. Whereas a "lightweight" tag
   is simply a name for an object (usually a commit object).

   Annotated tags are meant for release while lightweight tags are meant
   for private or temporary object labels. For this reason, some git
   commands for naming objects (like git describe) will ignore lightweight
   tags by default.

OPTIONS

   -a, --annotate
       Make an unsigned, annotated tag object

   -s, --sign
       Make a GPG-signed tag, using the default e-mail address's key.

   -u <keyid>, --local-user=<keyid>
       Make a GPG-signed tag, using the given key.

   -f, --force
       Replace an existing tag with the given name (instead of failing)

   -d, --delete
       Delete existing tags with the given names.

   -v, --verify
       Verify the GPG signature of the given tag names.

   -n<num>
       <num> specifies how many lines from the annotation, if any, are
       printed when using -l. The default is not to print any annotation
       lines. If no number is given to -n, only the first line is printed.
       If the tag is not annotated, the commit message is displayed
       instead.

   -l <pattern>, --list <pattern>
       List tags with names that match the given pattern (or all if no
       pattern is given). Running "git tag" without arguments also lists
       all tags. The pattern is a shell wildcard (i.e., matched using
       fnmatch(3)). Multiple patterns may be given; if any of them
       matches, the tag is shown.

   --sort=<key>
       Sort based on the key given. Prefix - to sort in descending order
       of the value. You may use the --sort=<key> option multiple times,
       in which case the last key becomes the primary key. Also supports
       "version:refname" or "v:refname" (tag names are treated as
       versions). The "version:refname" sort order can also be affected by
       the "versionsort.prereleaseSuffix" configuration variable. The keys
       supported are the same as those in git for-each-ref. Sort order
       defaults to the value configured for the tag.sort variable if it
       exists, or lexicographic order otherwise. See git-config(1).

   --column[=<options>], --no-column
       Display tag listing in columns. See configuration variable
       column.tag for option syntax.--column and --no-column without
       options are equivalent to always and never respectively.

       This option is only applicable when listing tags without annotation
       lines.

   --contains [<commit>]
       Only list tags which contain the specified commit (HEAD if not
       specified).

   --points-at <object>
       Only list tags of the given object.

   -m <msg>, --message=<msg>
       Use the given tag message (instead of prompting). If multiple -m
       options are given, their values are concatenated as separate
       paragraphs. Implies -a if none of -a, -s, or -u <keyid> is given.

   -F <file>, --file=<file>
       Take the tag message from the given file. Use - to read the message
       from the standard input. Implies -a if none of -a, -s, or -u
       <keyid> is given.

   --cleanup=<mode>
       This option sets how the tag message is cleaned up. The <mode> can
       be one of verbatim, whitespace and strip. The strip mode is
       default. The verbatim mode does not change message at all,
       whitespace removes just leading/trailing whitespace lines and strip
       removes both whitespace and commentary.

   --create-reflog
       Create a reflog for the tag.

   <tagname>
       The name of the tag to create, delete, or describe. The new tag
       name must pass all checks defined by git-check-ref-format(1). Some
       of these checks may restrict the characters allowed in a tag name.

   <commit>, <object>
       The object that the new tag will refer to, usually a commit.
       Defaults to HEAD.

   <format>
       A string that interpolates %(fieldname) from the object pointed at
       by a ref being shown. The format is the same as that of git-for-
       each-ref(1). When unspecified, defaults to %(refname:strip=2).

   --[no-]merged [<commit>]
       Only list tags whose tips are reachable, or not reachable if
       --no-merged is used, from the specified commit (HEAD if not
       specified).

CONFIGURATION

   By default, git tag in sign-with-default mode (-s) will use your
   committer identity (of the form Your Name <your@email.address>) to find
   a key. If you want to use a different default key, you can specify it
   in the repository configuration as follows:

       [user]
           signingKey = <gpg-keyid>

DISCUSSION

   On Re-tagging
   What should you do when you tag a wrong commit and you would want to
   re-tag?

   If you never pushed anything out, just re-tag it. Use "-f" to replace
   the old one. And you're done.

   But if you have pushed things out (or others could just read your
   repository directly), then others will have already seen the old tag.
   In that case you can do one of two things:

    1. The sane thing. Just admit you screwed up, and use a different
       name. Others have already seen one tag-name, and if you keep the
       same name, you may be in the situation that two people both have
       "version X", but they actually have different "X"'s. So just call
       it "X.1" and be done with it.

    2. The insane thing. You really want to call the new version "X" too,
       even though others have already seen the old one. So just use git
       tag -f again, as if you hadn't already published the old one.

   However, Git does not (and it should not) change tags behind users
   back. So if somebody already got the old tag, doing a git pull on your
   tree shouldn't just make them overwrite the old one.

   If somebody got a release tag from you, you cannot just change the tag
   for them by updating your own one. This is a big security issue, in
   that people MUST be able to trust their tag-names. If you really want
   to do the insane thing, you need to just fess up to it, and tell people
   that you messed up. You can do that by making a very public
   announcement saying:

       Ok, I messed up, and I pushed out an earlier version tagged as X. I
       then fixed something, and retagged the *fixed* tree as X again.

       If you got the wrong tag, and want the new one, please delete
       the old one and fetch the new one by doing:

               git tag -d X
               git fetch origin tag X

       to get my updated tag.

       You can test which tag you have by doing

               git rev-parse X

       which should return 0123456789abcdef.. if you have the new version.

       Sorry for the inconvenience.

   Does this seem a bit complicated? It should be. There is no way that it
   would be correct to just "fix" it automatically. People need to know
   that their tags might have been changed.

   On Automatic following
   If you are following somebody else's tree, you are most likely using
   remote-tracking branches (eg. refs/remotes/origin/master). You usually
   want the tags from the other end.

   On the other hand, if you are fetching because you would want a
   one-shot merge from somebody else, you typically do not want to get
   tags from there. This happens more often for people near the toplevel
   but not limited to them. Mere mortals when pulling from each other do
   not necessarily want to automatically get private anchor point tags
   from the other person.

   Often, "please pull" messages on the mailing list just provide two
   pieces of information: a repo URL and a branch name; this is designed
   to be easily cut&pasted at the end of a git fetch command line:

       Linus, please pull from

               git://git..../proj.git master

       to get the following updates...

   becomes:

       $ git pull git://git..../proj.git master

   In such a case, you do not want to automatically follow the other
   person's tags.

   One important aspect of Git is its distributed nature, which largely
   means there is no inherent "upstream" or "downstream" in the system. On
   the face of it, the above example might seem to indicate that the tag
   namespace is owned by the upper echelon of people and that tags only
   flow downwards, but that is not the case. It only shows that the usage
   pattern determines who are interested in whose tags.

   A one-shot pull is a sign that a commit history is now crossing the
   boundary between one circle of people (e.g. "people who are primarily
   interested in the networking part of the kernel") who may have their
   own set of tags (e.g. "this is the third release candidate from the
   networking group to be proposed for general consumption with 2.6.21
   release") to another circle of people (e.g. "people who integrate
   various subsystem improvements"). The latter are usually not interested
   in the detailed tags used internally in the former group (that is what
   "internal" means). That is why it is desirable not to follow tags
   automatically in this case.

   It may well be that among networking people, they may want to exchange
   the tags internal to their group, but in that workflow they are most
   likely tracking each other's progress by having remote-tracking
   branches. Again, the heuristic to automatically follow such tags is a
   good thing.

   On Backdating Tags
   If you have imported some changes from another VCS and would like to
   add tags for major releases of your work, it is useful to be able to
   specify the date to embed inside of the tag object; such data in the
   tag object affects, for example, the ordering of tags in the gitweb
   interface.

   To set the date used in future tag objects, set the environment
   variable GIT_COMMITTER_DATE (see the later discussion of possible
   values; the most common form is "YYYY-MM-DD HH:MM").

   For example:

       $ GIT_COMMITTER_DATE="2006-10-02 10:31" git tag -s v1.0.1

DATE FORMATS

   The GIT_AUTHOR_DATE, GIT_COMMITTER_DATE environment variables support
   the following date formats:

   Git internal format
       It is <unix timestamp> <time zone offset>, where <unix timestamp>
       is the number of seconds since the UNIX epoch.  <time zone offset>
       is a positive or negative offset from UTC. For example CET (which
       is 2 hours ahead UTC) is +0200.

   RFC 2822
       The standard email format as described by RFC 2822, for example
       Thu, 07 Apr 2005 22:13:13 +0200.

   ISO 8601
       Time and date specified by the ISO 8601 standard, for example
       2005-04-07T22:13:13. The parser accepts a space instead of the T
       character as well.

           Note
           In addition, the date part is accepted in the following
           formats: YYYY.MM.DD, MM/DD/YYYY and DD.MM.YYYY.

SEE ALSO

   git-check-ref-format(1). git-config(1).

GIT

   Part of the git(1) suite





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