GIT-REV-PARSE(1)                  Git Manual                  GIT-REV-PARSE(1)



NAME
       git-rev-parse - Pick out and massage parameters

SYNOPSIS
       git rev-parse [ --option ] <args>...


DESCRIPTION
       Many Git porcelainish commands take mixture of flags (i.e. parameters
       that begin with a dash -) and parameters meant for the underlying git
       rev-list command they use internally and flags and parameters for the
       other commands they use downstream of git rev-list. This command is
       used to distinguish between them.

OPTIONS
   Operation Modes
       Each of these options must appear first on the command line.

       --parseopt
           Use git rev-parse in option parsing mode (see PARSEOPT section
           below).

       --sq-quote
           Use git rev-parse in shell quoting mode (see SQ-QUOTE section
           below). In contrast to the --sq option below, this mode does only
           quoting. Nothing else is done to command input.

   Options for --parseopt
       --keep-dashdash
           Only meaningful in --parseopt mode. Tells the option parser to echo
           out the first -- met instead of skipping it.

       --stop-at-non-option
           Only meaningful in --parseopt mode. Lets the option parser stop at
           the first non-option argument. This can be used to parse
           sub-commands that take options themselves.

       --stuck-long
           Only meaningful in --parseopt mode. Output the options in their
           long form if available, and with their arguments stuck.

   Options for Filtering
       --revs-only
           Do not output flags and parameters not meant for git rev-list
           command.

       --no-revs
           Do not output flags and parameters meant for git rev-list command.

       --flags
           Do not output non-flag parameters.

       --no-flags
           Do not output flag parameters.

   Options for Output
       --default <arg>
           If there is no parameter given by the user, use <arg> instead.

       --prefix <arg>
           Behave as if git rev-parse was invoked from the <arg> subdirectory
           of the working tree. Any relative filenames are resolved as if they
           are prefixed by <arg> and will be printed in that form.

           This can be used to convert arguments to a command run in a
           subdirectory so that they can still be used after moving to the
           top-level of the repository. For example:

               prefix=$(git rev-parse --show-prefix)
               cd "$(git rev-parse --show-toplevel)"
               eval "set -- $(git rev-parse --sq --prefix "$prefix" "$@")"


       --verify
           Verify that exactly one parameter is provided, and that it can be
           turned into a raw 20-byte SHA-1 that can be used to access the
           object database. If so, emit it to the standard output; otherwise,
           error out.

           If you want to make sure that the output actually names an object
           in your object database and/or can be used as a specific type of
           object For example, git rev-parse "$VAR^{commit}" will make sure
           $VAR names an existing object that is a commit-ish (i.e. a commit,
           or an annotated tag that points at a commit). To make sure that
           $VAR names an existing object of any type, git rev-parse
           "$VAR^{object}" can be used.

       -q, --quiet
           Only meaningful in --verify mode. Do not output an error message if
           the first argument is not a valid object name; instead exit with
           non-zero status silently.

       --sq
           Usually the output is made one line per flag and parameter. This
           option makes output a single line, properly quoted for consumption
           by shell. Useful when you expect your parameter to contain
           whitespaces and newlines (e.g. when using pickaxe -S with git
           diff-*). In contrast to the --sq-quote option, the command input is
           still interpreted as usual.

       --not
           When showing object names, prefix them with ^ and strip ^ prefix
           from the object names that already have one.

       --abbrev-ref[=(strict|loose)]
           A non-ambiguous short name of the objects name. The option
           core.warnAmbiguousRefs is used to select the strict abbreviation
           mode.

       --short, --short=number
           Instead of outputting the full SHA-1 values of object names try to
           abbreviate them to a shorter unique name. When no length is
           specified 7 is used. The minimum length is 4.

       --symbolic
           Usually the object names are output in SHA-1 form (with possible ^
           prefix); this option makes them output in a form as close to the
           original input as possible.

       --symbolic-full-name
           This is similar to --symbolic, but it omits input that are not refs
           (i.e. branch or tag names; or more explicitly disambiguating
           "heads/master" form, when you want to name the "master" branch when
           there is an unfortunately named tag "master"), and show them as
           full refnames (e.g. "refs/heads/master").

   Options for Objects
       --all
           Show all refs found in refs/.

       --branches[=pattern], --tags[=pattern], --remotes[=pattern]
           Show all branches, tags, or remote-tracking branches, respectively
           (i.e., refs found in refs/heads, refs/tags, or refs/remotes,
           respectively).

           If a pattern is given, only refs matching the given shell glob are
           shown. If the pattern does not contain a globbing character (?, *,
           or [), it is turned into a prefix match by appending /*.

       --glob=pattern
           Show all refs matching the shell glob pattern pattern. If the
           pattern does not start with refs/, this is automatically prepended.
           If the pattern does not contain a globbing character (?, *, or [),
           it is turned into a prefix match by appending /*.

       --exclude=<glob-pattern>
           Do not include refs matching <glob-pattern> that the next --all,
           --branches, --tags, --remotes, or --glob would otherwise consider.
           Repetitions of this option accumulate exclusion patterns up to the
           next --all, --branches, --tags, --remotes, or --glob option (other
           options or arguments do not clear accumlated patterns).

           The patterns given should not begin with refs/heads, refs/tags, or
           refs/remotes when applied to --branches, --tags, or --remotes,
           respectively, and they must begin with refs/ when applied to --glob
           or --all. If a trailing /* is intended, it must be given
           explicitly.

       --disambiguate=<prefix>
           Show every object whose name begins with the given prefix. The
           <prefix> must be at least 4 hexadecimal digits long to avoid
           listing each and every object in the repository by mistake.

   Options for Files
       --local-env-vars
           List the GIT_* environment variables that are local to the
           repository (e.g. GIT_DIR or GIT_WORK_TREE, but not GIT_EDITOR).
           Only the names of the variables are listed, not their value, even
           if they are set.

       --git-dir
           Show $GIT_DIR if defined. Otherwise show the path to the .git
           directory. The path shown, when relative, is relative to the
           current working directory.

           If $GIT_DIR is not defined and the current directory is not
           detected to lie in a Git repository or work tree print a message to
           stderr and exit with nonzero status.

       --is-inside-git-dir
           When the current working directory is below the repository
           directory print "true", otherwise "false".

       --is-inside-work-tree
           When the current working directory is inside the work tree of the
           repository print "true", otherwise "false".

       --is-bare-repository
           When the repository is bare print "true", otherwise "false".

       --resolve-git-dir <path>
           Check if <path> is a valid repository or a gitfile that points at a
           valid repository, and print the location of the repository. If
           <path> is a gitfile then the resolved path to the real repository
           is printed.

       --show-cdup
           When the command is invoked from a subdirectory, show the path of
           the top-level directory relative to the current directory
           (typically a sequence of "../", or an empty string).

       --show-prefix
           When the command is invoked from a subdirectory, show the path of
           the current directory relative to the top-level directory.

       --show-toplevel
           Show the absolute path of the top-level directory.

       --shared-index-path
           Show the path to the shared index file in split index mode, or
           empty if not in split-index mode.

   Other Options
       --since=datestring, --after=datestring
           Parse the date string, and output the corresponding --max-age=
           parameter for git rev-list.

       --until=datestring, --before=datestring
           Parse the date string, and output the corresponding --min-age=
           parameter for git rev-list.

       <args>...
           Flags and parameters to be parsed.

SPECIFYING REVISIONS
       A revision parameter <rev> typically, but not necessarily, names a
       commit object. It uses what is called an extended SHA-1 syntax. Here
       are various ways to spell object names. The ones listed near the end of
       this list name trees and blobs contained in a commit.

       <sha1>, e.g. dae86e1950b1277e545cee180551750029cfe735, dae86e
           The full SHA-1 object name (40-byte hexadecimal string), or a
           leading substring that is unique within the repository. E.g.
           dae86e1950b1277e545cee180551750029cfe735 and dae86e both name the
           same commit object if there is no other object in your repository
           whose object name starts with dae86e.

       <describeOutput>, e.g. v1.7.4.2-679-g3bee7fb
           Output from git describe; i.e. a closest tag, optionally followed
           by a dash and a number of commits, followed by a dash, a g, and an
           abbreviated object name.

       <refname>, e.g. master, heads/master, refs/heads/master
           A symbolic ref name. E.g.  master typically means the commit object
           referenced by refs/heads/master. If you happen to have both
           heads/master and tags/master, you can explicitly say heads/master
           to tell Git which one you mean. When ambiguous, a <refname> is
           disambiguated by taking the first match in the following rules:

            1. If $GIT_DIR/<refname> exists, that is what you mean (this is
               usually useful only for HEAD, FETCH_HEAD, ORIG_HEAD, MERGE_HEAD
               and CHERRY_PICK_HEAD);

            2. otherwise, refs/<refname> if it exists;

            3. otherwise, refs/tags/<refname> if it exists;

            4. otherwise, refs/heads/<refname> if it exists;

            5. otherwise, refs/remotes/<refname> if it exists;

            6. otherwise, refs/remotes/<refname>/HEAD if it exists.

               HEAD names the commit on which you based the changes in the
               working tree.  FETCH_HEAD records the branch which you fetched
               from a remote repository with your last git fetch invocation.
               ORIG_HEAD is created by commands that move your HEAD in a
               drastic way, to record the position of the HEAD before their
               operation, so that you can easily change the tip of the branch
               back to the state before you ran them.  MERGE_HEAD records the
               commit(s) which you are merging into your branch when you run
               git merge.  CHERRY_PICK_HEAD records the commit which you are
               cherry-picking when you run git cherry-pick.

               Note that any of the refs/* cases above may come either from
               the $GIT_DIR/refs directory or from the $GIT_DIR/packed-refs
               file. While the ref name encoding is unspecified, UTF-8 is
               preferred as some output processing may assume ref names in
               UTF-8.

       @
           @ alone is a shortcut for HEAD.

       <refname>@{<date>}, e.g. master@{yesterday}, HEAD@{5 minutes ago}
           A ref followed by the suffix @ with a date specification enclosed
           in a brace pair (e.g.  {yesterday}, {1 month 2 weeks 3 days 1 hour
           1 second ago} or {1979-02-26 18:30:00}) specifies the value of the
           ref at a prior point in time. This suffix may only be used
           immediately following a ref name and the ref must have an existing
           log ($GIT_DIR/logs/<ref>). Note that this looks up the state of
           your local ref at a given time; e.g., what was in your local master
           branch last week. If you want to look at commits made during
           certain times, see --since and --until.

       <refname>@{<n>}, e.g. master@{1}
           A ref followed by the suffix @ with an ordinal specification
           enclosed in a brace pair (e.g.  {1}, {15}) specifies the n-th prior
           value of that ref. For example master@{1} is the immediate prior
           value of master while master@{5} is the 5th prior value of master.
           This suffix may only be used immediately following a ref name and
           the ref must have an existing log ($GIT_DIR/logs/<refname>).

       @{<n>}, e.g. @{1}
           You can use the @ construct with an empty ref part to get at a
           reflog entry of the current branch. For example, if you are on
           branch blabla then @{1} means the same as blabla@{1}.

       @{-<n>}, e.g. @{-1}
           The construct @{-<n>} means the <n>th branch/commit checked out
           before the current one.

       <branchname>@{upstream}, e.g. master@{upstream}, @{u}
           The suffix @{upstream} to a branchname (short form
           <branchname>@{u}) refers to the branch that the branch specified by
           branchname is set to build on top of (configured with
           branch.<name>.remote and branch.<name>.merge). A missing branchname
           defaults to the current one.

       <rev>^, e.g. HEAD^, v1.5.1^0
           A suffix ^ to a revision parameter means the first parent of that
           commit object.  ^<n> means the <n>th parent (i.e.  <rev>^ is
           equivalent to <rev>^1). As a special rule, <rev>^0 means the commit
           itself and is used when <rev> is the object name of a tag object
           that refers to a commit object.

       <rev>~<n>, e.g. master~3
           A suffix ~<n> to a revision parameter means the commit object that
           is the <n>th generation ancestor of the named commit object,
           following only the first parents. I.e.  <rev>~3 is equivalent to
           <rev>^^^ which is equivalent to <rev>^1^1^1. See below for an
           illustration of the usage of this form.

       <rev>^{<type>}, e.g. v0.99.8^{commit}
           A suffix ^ followed by an object type name enclosed in brace pair
           means dereference the object at <rev> recursively until an object
           of type <type> is found or the object cannot be dereferenced
           anymore (in which case, barf). For example, if <rev> is a
           commit-ish, <rev>^{commit} describes the corresponding commit
           object. Similarly, if <rev> is a tree-ish, <rev>^{tree} describes
           the corresponding tree object.  <rev>^0 is a short-hand for
           <rev>^{commit}.

           rev^{object} can be used to make sure rev names an object that
           exists, without requiring rev to be a tag, and without
           dereferencing rev; because a tag is already an object, it does not
           have to be dereferenced even once to get to an object.

           rev^{tag} can be used to ensure that rev identifies an existing tag
           object.

       <rev>^{}, e.g. v0.99.8^{}
           A suffix ^ followed by an empty brace pair means the object could
           be a tag, and dereference the tag recursively until a non-tag
           object is found.

       <rev>^{/<text>}, e.g. HEAD^{/fix nasty bug}
           A suffix ^ to a revision parameter, followed by a brace pair that
           contains a text led by a slash, is the same as the :/fix nasty bug
           syntax below except that it returns the youngest matching commit
           which is reachable from the <rev> before ^.

       :/<text>, e.g. :/fix nasty bug
           A colon, followed by a slash, followed by a text, names a commit
           whose commit message matches the specified regular expression. This
           name returns the youngest matching commit which is reachable from
           any ref. If the commit message starts with a !  you have to repeat
           that; the special sequence :/!, followed by something else than !,
           is reserved for now. The regular expression can match any part of
           the commit message. To match messages starting with a string, one
           can use e.g.  :/^foo.

       <rev>:<path>, e.g. HEAD:README, :README, master:./README
           A suffix : followed by a path names the blob or tree at the given
           path in the tree-ish object named by the part before the colon.
           :path (with an empty part before the colon) is a special case of
           the syntax described next: content recorded in the index at the
           given path. A path starting with ./ or ../ is relative to the
           current working directory. The given path will be converted to be
           relative to the working tree's root directory. This is most useful
           to address a blob or tree from a commit or tree that has the same
           tree structure as the working tree.

       :<n>:<path>, e.g. :0:README, :README
           A colon, optionally followed by a stage number (0 to 3) and a
           colon, followed by a path, names a blob object in the index at the
           given path. A missing stage number (and the colon that follows it)
           names a stage 0 entry. During a merge, stage 1 is the common
           ancestor, stage 2 is the target branch's version (typically the
           current branch), and stage 3 is the version from the branch which
           is being merged.

       Here is an illustration, by Jon Loeliger. Both commit nodes B and C are
       parents of commit node A. Parent commits are ordered left-to-right.

           G   H   I   J
            \ /     \ /
             D   E   F
              \  |  / \
               \ | /   |
                \|/    |
                 B     C
                  \   /
                   \ /
                    A

           A =      = A^0
           B = A^   = A^1     = A~1
           C = A^2  = A^2
           D = A^^  = A^1^1   = A~2
           E = B^2  = A^^2
           F = B^3  = A^^3
           G = A^^^ = A^1^1^1 = A~3
           H = D^2  = B^^2    = A^^^2  = A~2^2
           I = F^   = B^3^    = A^^3^
           J = F^2  = B^3^2   = A^^3^2

SPECIFYING RANGES
       History traversing commands such as git log operate on a set of
       commits, not just a single commit. To these commands, specifying a
       single revision with the notation described in the previous section
       means the set of commits reachable from that commit, following the
       commit ancestry chain.

       To exclude commits reachable from a commit, a prefix ^ notation is
       used. E.g. ^r1 r2 means commits reachable from r2 but exclude the ones
       reachable from r1.

       This set operation appears so often that there is a shorthand for it.
       When you have two commits r1 and r2 (named according to the syntax
       explained in SPECIFYING REVISIONS above), you can ask for commits that
       are reachable from r2 excluding those that are reachable from r1 by ^r1
       r2 and it can be written as r1..r2.

       A similar notation r1...r2 is called symmetric difference of r1 and r2
       and is defined as r1 r2 --not $(git merge-base --all r1 r2). It is the
       set of commits that are reachable from either one of r1 or r2 but not
       from both.

       In these two shorthands, you can omit one end and let it default to
       HEAD. For example, origin.. is a shorthand for origin..HEAD and asks
       "What did I do since I forked from the origin branch?" Similarly,
       ..origin is a shorthand for HEAD..origin and asks "What did the origin
       do since I forked from them?" Note that .. would mean HEAD..HEAD which
       is an empty range that is both reachable and unreachable from HEAD.

       Two other shorthands for naming a set that is formed by a commit and
       its parent commits exist. The r1^@ notation means all parents of r1.
       r1^! includes commit r1 but excludes all of its parents.

       To summarize:

       <rev>
           Include commits that are reachable from (i.e. ancestors of) <rev>.

       ^<rev>
           Exclude commits that are reachable from (i.e. ancestors of) <rev>.

       <rev1>..<rev2>
           Include commits that are reachable from <rev2> but exclude those
           that are reachable from <rev1>. When either <rev1> or <rev2> is
           omitted, it defaults to HEAD.

       <rev1>...<rev2>
           Include commits that are reachable from either <rev1> or <rev2> but
           exclude those that are reachable from both. When either <rev1> or
           <rev2> is omitted, it defaults to HEAD.

       <rev>^@, e.g. HEAD^@
           A suffix ^ followed by an at sign is the same as listing all
           parents of <rev> (meaning, include anything reachable from its
           parents, but not the commit itself).

       <rev>^!, e.g. HEAD^!
           A suffix ^ followed by an exclamation mark is the same as giving
           commit <rev> and then all its parents prefixed with ^ to exclude
           them (and their ancestors).

       Here are a handful of examples:

           D                G H D
           D F              G H I J D F
           ^G D             H D
           ^D B             E I J F B
           B..C             C
           B...C            G H D E B C
           ^D B C           E I J F B C
           C                I J F C
           C^@              I J F
           C^!              C
           F^! D            G H D F

PARSEOPT
       In --parseopt mode, git rev-parse helps massaging options to bring to
       shell scripts the same facilities C builtins have. It works as an
       option normalizer (e.g. splits single switches aggregate values), a bit
       like getopt(1) does.

       It takes on the standard input the specification of the options to
       parse and understand, and echoes on the standard output a string
       suitable for sh(1) eval to replace the arguments with normalized ones.
       In case of error, it outputs usage on the standard error stream, and
       exits with code 129.

       Note: Make sure you quote the result when passing it to eval. See below
       for an example.

   Input Format
       git rev-parse --parseopt input format is fully text based. It has two
       parts, separated by a line that contains only --. The lines before the
       separator (should be one or more) are used for the usage. The lines
       after the separator describe the options.

       Each line of options has this format:

           <opt-spec><flags>*<arg-hint>? SP+ help LF



       <opt-spec>
           its format is the short option character, then the long option name
           separated by a comma. Both parts are not required, though at least
           one is necessary.  h,help, dry-run and f are all three correct
           <opt-spec>.

       <flags>
           <flags> are of *, =, ?  or !.

           o   Use = if the option takes an argument.

           o   Use ?  to mean that the option takes an optional argument. You
               probably want to use the --stuck-long mode to be able to
               unambiguously parse the optional argument.

           o   Use * to mean that this option should not be listed in the
               usage generated for the -h argument. It's shown for --help-all
               as documented in gitcli(7).

           o   Use !  to not make the corresponding negated long option
               available.

       <arg-hint>
           <arg-hint>, if specified, is used as a name of the argument in the
           help output, for options that take arguments.  <arg-hint> is
           terminated by the first whitespace. It is customary to use a dash
           to separate words in a multi-word argument hint.

       The remainder of the line, after stripping the spaces, is used as the
       help associated to the option.

       Blank lines are ignored, and lines that don't match this specification
       are used as option group headers (start the line with a space to create
       such lines on purpose).

   Example
           OPTS_SPEC="\
           some-command [options] <args>...

           some-command does foo and bar!
           --
           h,help    show the help

           foo       some nifty option --foo
           bar=      some cool option --bar with an argument
           baz=arg   another cool option --baz with a named argument
           qux?path  qux may take a path argument but has meaning by itself

             An option group Header
           C?        option C with an optional argument"

           eval "$(echo "$OPTS_SPEC" | git rev-parse --parseopt -- "$@" || echo exit $?)"


   Usage text
       When "$@" is -h or --help in the above example, the following usage
       text would be shown:

           usage: some-command [options] <args>...

               some-command does foo and bar!

               -h, --help            show the help
               --foo                 some nifty option --foo
               --bar ...             some cool option --bar with an argument
               --baz <arg>           another cool option --baz with a named argument
               --qux[=<path>]        qux may take a path argument but has meaning by itself

           An option group Header
               -C[...]               option C with an optional argument


SQ-QUOTE
       In --sq-quote mode, git rev-parse echoes on the standard output a
       single line suitable for sh(1) eval. This line is made by normalizing
       the arguments following --sq-quote. Nothing other than quoting the
       arguments is done.

       If you want command input to still be interpreted as usual by git
       rev-parse before the output is shell quoted, see the --sq option.

   Example
           $ cat >your-git-script.sh <<\EOF
           #!/bin/sh
           args=$(git rev-parse --sq-quote "$@")   # quote user-supplied arguments
           command="git frotz -n24 $args"          # and use it inside a handcrafted
                                                   # command line
           eval "$command"
           EOF

           $ sh your-git-script.sh "a b'c"


EXAMPLES
       o   Print the object name of the current commit:

               $ git rev-parse --verify HEAD


       o   Print the commit object name from the revision in the $REV shell
           variable:

               $ git rev-parse --verify $REV^{commit}

           This will error out if $REV is empty or not a valid revision.

       o   Similar to above:

               $ git rev-parse --default master --verify $REV

           but if $REV is empty, the commit object name from master will be
           printed.

GIT
       Part of the git(1) suite



Git 2.1.4                         03/19/2016                  GIT-REV-PARSE(1)
