Documentation/git-rev-parse.txt - git - Git at Google


            
            git-rev-parse(1)

            
            ================


            NAME

            
            ----

            
            git-rev-parse - Pick out and massage parameters


            SYNOPSIS

            
            --------

            
            [verse]

            
            '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

            
            you require, you can add the `^{type}` peeling operator to the parameter.

            
            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.

            
            	SHA-1s for valid object names are printed to stdout on success.


            --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-{asterisk}'). In contrast to the `--sq-quote` option,

            
            	the command input is still interpreted as usual.


            --not::

            
            	When showing object names, prefix them with '{caret}' and

            
            	strip '{caret}' 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 '{caret}' 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

            
            	accumulated 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 '/{asterisk}' 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.


            --git-common-dir::

            
            	Show `$GIT_COMMON_DIR` if defined, else `$GIT_DIR`.


            --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.


            --git-path <path>::

            
            	Resolve "$GIT_DIR/<path>" and takes other path relocation

            
            	variables such as $GIT_OBJECT_DIRECTORY,

            
            	$GIT_INDEX_FILE... into account. For example, if

            
            	$GIT_OBJECT_DIRECTORY is set to /foo/bar then "git rev-parse

            
            	--git-path objects/abc" returns /foo/bar/abc.


            --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.


            include::revisions.txt[]


            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. May not contain any of the `<flags>` characters.

            
            	`h,help`, `dry-run` and `f` are examples of correct `<opt-spec>`.


            `<flags>`::

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

            
            	* Use `=` if the option takes an argument.


            	* 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.


            	* 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 linkgit:gitcli[7].


            	* 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

            
            --------


            * Print the object name of the current commit:

            
            +

            
            ------------

            
            $ git rev-parse --verify HEAD

            
            ------------


            * 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.


            * 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 linkgit:git[1] suite
	git-rev-parse(1)
	================

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


	SYNOPSIS
	--------
	[verse]
	'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
	you require, you can add the `^{type}` peeling operator to the parameter.
	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.
	SHA-1s for valid object names are printed to stdout on success.

	--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-{asterisk}'). In contrast to the `--sq-quote` option,
	the command input is still interpreted as usual.

	--not::
	When showing object names, prefix them with '{caret}' and
	strip '{caret}' 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 '{caret}' 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
	accumulated 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 '/{asterisk}' 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.

	--git-common-dir::
	Show `$GIT_COMMON_DIR` if defined, else `$GIT_DIR`.

	--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.

	--git-path <path>::
	Resolve "$GIT_DIR/<path>" and takes other path relocation
	variables such as $GIT_OBJECT_DIRECTORY,
	$GIT_INDEX_FILE... into account. For example, if
	$GIT_OBJECT_DIRECTORY is set to /foo/bar then "git rev-parse
	--git-path objects/abc" returns /foo/bar/abc.

	--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.


	include::revisions.txt[]

	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. May not contain any of the `<flags>` characters.
	`h,help`, `dry-run` and `f` are examples of correct `<opt-spec>`.

	`<flags>`::
	`<flags>` are of `*`, `=`, `?` or `!`.
	* Use `=` if the option takes an argument.

	* 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.

	* 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 linkgit:gitcli[7].

	* 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
	--------

	* Print the object name of the current commit:
	+
	------------
	$ git rev-parse --verify HEAD
	------------

	* 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.

	* 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 linkgit:git[1] suite