gitcli.adoc - pub/scm/git/git-htmldocs - Git at Google


            
            gitcli(7)

            
            =========


            NAME

            
            ----

            
            gitcli - Git command-line interface and conventions


            SYNOPSIS

            
            --------

            
            gitcli


            DESCRIPTION

            
            -----------


            This manual describes the convention used throughout Git CLI.


            Many commands take revisions (most often "commits", but sometimes

            
            "tree-ish", depending on the context and command) and paths as their

            
            arguments.  Here are the rules:


             * Options come first and then args.

            
                A subcommand may take dashed options (which may take their own

            
                arguments, e.g. "--max-parents 2") and arguments.  You SHOULD

            
                give dashed options first and then arguments.  Some commands may

            
                accept dashed options after you have already given non-option

            
                arguments (which may make the command ambiguous), but you should

            
                not rely on it (because eventually we may find a way to fix

            
                these ambiguities by enforcing the "options then args" rule).


             * Revisions come first and then paths.

            
               E.g. in `git diff v1.0 v2.0 arch/x86 include/asm-x86`,

            
               `v1.0` and `v2.0` are revisions and `arch/x86` and `include/asm-x86`

            
               are paths.


             * When an argument can be misunderstood as either a revision or a path,

            
               they can be disambiguated by placing `--` between them.

            
               E.g. `git diff -- HEAD` is, "I have a file called HEAD in my work

            
               tree.  Please show changes between the version I staged in the index

            
               and what I have in the work tree for that file", not "show the difference

            
               between the HEAD commit and the work tree as a whole".  You can say

            
               `git diff HEAD --` to ask for the latter.


             * Without disambiguating `--`, Git makes a reasonable guess, but errors

            
               out and asks you to disambiguate when ambiguous.  E.g. if you have a

            
               file called HEAD in your work tree, `git diff HEAD` is ambiguous, and

            
               you have to say either `git diff HEAD --` or `git diff -- HEAD` to

            
               disambiguate.


             * Because `--` disambiguates revisions and paths in some commands, it

            
               cannot be used for those commands to separate options and revisions.

            
               You can use `--end-of-options` for this (it also works for commands

            
               that do not distinguish between revisions in paths, in which case it

            
               is simply an alias for `--`).

            
            +

            
            When writing a script that is expected to handle random user-input, it is

            
            a good practice to make it explicit which arguments are which by placing

            
            disambiguating `--` at appropriate places.


             * Many commands allow wildcards in paths, but you need to protect

            
               them from getting globbed by the shell.  These two mean different

            
               things:

            
            +

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

            
            $ git restore *.c

            
            $ git restore \*.c

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

            
            +

            
            The former lets your shell expand the fileglob, and you are asking

            
            the dot-C files in your working tree to be overwritten with the version

            
            in the index.  The latter passes the `*.c` to Git, and you are asking

            
            the paths in the index that match the pattern to be checked out to your

            
            working tree.  After running `git add hello.c; rm hello.c`, you will _not_

            
            see `hello.c` in your working tree with the former, but with the latter

            
            you will.


             * Just as the filesystem '.' (period) refers to the current directory,

            
               using a '.' as a repository name in Git (a dot-repository) is a relative

            
               path and means your current repository.


            Here are the rules regarding the "flags" that you should follow when you are

            
            scripting Git:


             * Splitting short options to separate words (prefer `git foo -a -b`

            
               to `git foo -ab`, the latter may not even work).


             * When a command-line option takes an argument, use the 'stuck' form.  In

            
               other words, write `git foo -oArg` instead of `git foo -o Arg` for short

            
               options, and `git foo --long-opt=Arg` instead of `git foo --long-opt Arg`

            
               for long options.  An option that takes optional option-argument must be

            
               written in the 'stuck' form.


             * Despite the above suggestion, when Arg is a path relative to the

            
               home directory of a user, e.g. `~/directory/file` or `~u/d/f`, you

            
               may want to use the separate form, e.g. `git foo --file ~/mine`,

            
               not `git foo --file=~/mine`.  The shell will expand `~/` in the

            
               former to your home directory, but most shells keep the tilde in

            
               the latter.  Some of our commands know how to tilde-expand the

            
               option value even when given in the stuck form, but not all of

            
               them do.


             * When you give a revision parameter to a command, make sure the parameter is

            
               not ambiguous with a name of a file in the work tree.  E.g. do not write

            
               `git log -1 HEAD` but write `git log -1 HEAD --`; the former will not work

            
               if you happen to have a file called `HEAD` in the work tree.


             * Many commands allow a long option `--option` to be abbreviated

            
               only to their unique prefix (e.g. if there is no other option

            
               whose name begins with `opt`, you may be able to spell `--opt` to

            
               invoke the `--option` flag), but you should fully spell them out

            
               when writing your scripts; later versions of Git may introduce a

            
               new option whose name shares the same prefix, e.g. `--optimize`,

            
               to make a short prefix that used to be unique no longer unique.


            ENHANCED OPTION PARSER

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

            
            From the Git 1.5.4 series and further, many Git commands (not all of them at the

            
            time of the writing though) come with an enhanced option parser.


            Here is a list of the facilities provided by this option parser.


            Magic Options

            
            ~~~~~~~~~~~~~

            
            Commands which have the enhanced option parser activated all understand a

            
            couple of magic command-line options:


            -h::

            
            	gives a pretty printed usage of the command.

            
            +

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

            
            $ git describe -h

            
            usage: git describe [<options>] <commit-ish>*

            
               or: git describe [<options>] --dirty


                --contains            find the tag that comes after the commit

            
                --debug               debug search strategy on stderr

            
                --all                 use any ref

            
                --tags                use any tag, even unannotated

            
                --long                always use long format

            
                --abbrev[=<n>]        use <n> digits to display SHA-1s

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

            
            +

            
            Note that some subcommand (e.g. `git grep`) may behave differently

            
            when there are things on the command line other than `-h`, but `git

            
            subcmd -h` without anything else on the command line is meant to

            
            consistently give the usage.


            --help-all::

            
            	Some Git commands take options that are only used for plumbing or that

            
            	are deprecated, and such options are hidden from the default usage. This

            
            	option gives the full list of options.


            Negating options

            
            ~~~~~~~~~~~~~~~~

            
            Options with long option names can be negated by prefixing `--no-`. For

            
            example, `git branch` has the option `--track` which is 'on' by default. You

            
            can use `--no-track` to override that behaviour. The same goes for `--color`

            
            and `--no-color`.


            Options trump configuration and environment

            
            ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


            When there is a configuration variable or an environment variable

            
            that tweak the behaviour of an aspect of a Git command, and also a

            
            command line option that tweaks the same, the command line option

            
            overrides what the configuration and/or environment variable say.


            For example, the `user.name` configuration variable is used to

            
            specify the human-readable name used by the `git commit` command to

            
            record the author and the committer name in a newly created commit.

            
            The `GIT_AUTHOR_NAME` environment variable, if set, takes precedence

            
            when deciding what author name to record.  The `--author=<author>`

            
            command line option of the `git commit` command, when given, takes

            
            precedence over these two sources of information.


            Aggregating short options

            
            ~~~~~~~~~~~~~~~~~~~~~~~~~

            
            Commands that support the enhanced option parser allow you to aggregate short

            
            options. This means that you can for example use `git rm -rf` or

            
            `git clean -fdx`.


            Abbreviating long options

            
            ~~~~~~~~~~~~~~~~~~~~~~~~~

            
            Commands that support the enhanced option parser accepts unique

            
            prefix of a long option as if it is fully spelled out, but use this

            
            with a caution.  For example, `git commit --amen` behaves as if you

            
            typed `git commit --amend`, but that is true only until a later version

            
            of Git introduces another option that shares the same prefix,

            
            e.g. `git commit --amenity` option.


            Separating argument from the option

            
            ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

            
            You can write the mandatory option parameter to an option as a separate

            
            word on the command line.  That means that all the following uses work:


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

            
            $ git foo --long-opt=Arg

            
            $ git foo --long-opt Arg

            
            $ git foo -oArg

            
            $ git foo -o Arg

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


            However, this is *NOT* allowed for switches with an optional value, where the

            
            'stuck' form must be used:


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

            
            $ git describe --abbrev HEAD     # correct

            
            $ git describe --abbrev=10 HEAD  # correct

            
            $ git describe --abbrev 10 HEAD  # NOT WHAT YOU MEANT

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


            Magic filename options

            
            ~~~~~~~~~~~~~~~~~~~~~~

            
            Options that take a filename allow a prefix `:(optional)`. For example:


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

            
            git commit -F :(optional)COMMIT_EDITMSG

            
            # if COMMIT_EDITMSG does not exist, the above is equivalent to

            
            git commit

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


            Like with configuration values, if the named file is missing Git behaves as if

            
            the option was not given at all. See "Values" in linkgit:git-config[1].


            NOTES ON FREQUENTLY CONFUSED OPTIONS

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


            Many commands that can work on files in the working tree

            
            and/or in the index can take `--cached` and/or `--index`

            
            options.  Sometimes people incorrectly think that, because

            
            the index was originally called cache, these two are

            
            synonyms.  They are *not* -- these two options mean very

            
            different things.


             * The `--cached` option is used to ask a command that

            
               usually works on files in the working tree to *only* work

            
               with the index.  For example, `git grep`, when used

            
               without a commit to specify from which commit to look for

            
               strings in, usually works on files in the working tree,

            
               but with the `--cached` option, it looks for strings in

            
               the index.


             * The `--index` option is used to ask a command that

            
               usually works on files in the working tree to *also*

            
               affect the index.  For example, `git stash apply` usually

            
               merges changes recorded in a stash entry to the working tree,

            
               but with the `--index` option, it also merges changes to

            
               the index as well.


            `git apply` command can be used with `--cached` and

            
            `--index` (but not at the same time).  Usually the command

            
            only affects the files in the working tree, but with

            
            `--index`, it patches both the files and their index

            
            entries, and with `--cached`, it modifies only the index

            
            entries.


            See also https://lore.kernel.org/git/7v64clg5u9.fsf@assigned-by-dhcp.cox.net/ and

            
            https://lore.kernel.org/git/7vy7ej9g38.fsf@gitster.siamese.dyndns.org/ for further

            
            information.


            Some other commands that also work on files in the working tree and/or

            
            in the index can take `--staged` and/or `--worktree`.


            * `--staged` is exactly like `--cached`, which is used to ask a

            
              command to only work on the index, not the working tree.


            * `--worktree` is the opposite, to ask a command to work on the

            
              working tree only, not the index.


            * The two options can be specified together to ask a command to work

            
              on both the index and the working tree.


            GIT

            
            ---

            
            Part of the linkgit:git[1] suite
	gitcli(7)
	=========

	NAME
	----
	gitcli - Git command-line interface and conventions

	SYNOPSIS
	--------
	gitcli


	DESCRIPTION
	-----------

	This manual describes the convention used throughout Git CLI.

	Many commands take revisions (most often "commits", but sometimes
	"tree-ish", depending on the context and command) and paths as their
	arguments. Here are the rules:

	* Options come first and then args.
	A subcommand may take dashed options (which may take their own
	arguments, e.g. "--max-parents 2") and arguments. You SHOULD
	give dashed options first and then arguments. Some commands may
	accept dashed options after you have already given non-option
	arguments (which may make the command ambiguous), but you should
	not rely on it (because eventually we may find a way to fix
	these ambiguities by enforcing the "options then args" rule).

	* Revisions come first and then paths.
	E.g. in `git diff v1.0 v2.0 arch/x86 include/asm-x86`,
	`v1.0` and `v2.0` are revisions and `arch/x86` and `include/asm-x86`
	are paths.

	* When an argument can be misunderstood as either a revision or a path,
	they can be disambiguated by placing `--` between them.
	E.g. `git diff -- HEAD` is, "I have a file called HEAD in my work
	tree. Please show changes between the version I staged in the index
	and what I have in the work tree for that file", not "show the difference
	between the HEAD commit and the work tree as a whole". You can say
	`git diff HEAD --` to ask for the latter.

	* Without disambiguating `--`, Git makes a reasonable guess, but errors
	out and asks you to disambiguate when ambiguous. E.g. if you have a
	file called HEAD in your work tree, `git diff HEAD` is ambiguous, and
	you have to say either `git diff HEAD --` or `git diff -- HEAD` to
	disambiguate.

	* Because `--` disambiguates revisions and paths in some commands, it
	cannot be used for those commands to separate options and revisions.
	You can use `--end-of-options` for this (it also works for commands
	that do not distinguish between revisions in paths, in which case it
	is simply an alias for `--`).
	+
	When writing a script that is expected to handle random user-input, it is
	a good practice to make it explicit which arguments are which by placing
	disambiguating `--` at appropriate places.

	* Many commands allow wildcards in paths, but you need to protect
	them from getting globbed by the shell. These two mean different
	things:
	+
	--------------------------------
	$ git restore *.c
	$ git restore \*.c
	--------------------------------
	+
	The former lets your shell expand the fileglob, and you are asking
	the dot-C files in your working tree to be overwritten with the version
	in the index. The latter passes the `*.c` to Git, and you are asking
	the paths in the index that match the pattern to be checked out to your
	working tree. After running `git add hello.c; rm hello.c`, you will _not_
	see `hello.c` in your working tree with the former, but with the latter
	you will.

	* Just as the filesystem '.' (period) refers to the current directory,
	using a '.' as a repository name in Git (a dot-repository) is a relative
	path and means your current repository.

	Here are the rules regarding the "flags" that you should follow when you are
	scripting Git:

	* Splitting short options to separate words (prefer `git foo -a -b`
	to `git foo -ab`, the latter may not even work).

	* When a command-line option takes an argument, use the 'stuck' form. In
	other words, write `git foo -oArg` instead of `git foo -o Arg` for short
	options, and `git foo --long-opt=Arg` instead of `git foo --long-opt Arg`
	for long options. An option that takes optional option-argument must be
	written in the 'stuck' form.

	* Despite the above suggestion, when Arg is a path relative to the
	home directory of a user, e.g. `~/directory/file` or `~u/d/f`, you
	may want to use the separate form, e.g. `git foo --file ~/mine`,
	not `git foo --file=~/mine`. The shell will expand `~/` in the
	former to your home directory, but most shells keep the tilde in
	the latter. Some of our commands know how to tilde-expand the
	option value even when given in the stuck form, but not all of
	them do.

	* When you give a revision parameter to a command, make sure the parameter is
	not ambiguous with a name of a file in the work tree. E.g. do not write
	`git log -1 HEAD` but write `git log -1 HEAD --`; the former will not work
	if you happen to have a file called `HEAD` in the work tree.

	* Many commands allow a long option `--option` to be abbreviated
	only to their unique prefix (e.g. if there is no other option
	whose name begins with `opt`, you may be able to spell `--opt` to
	invoke the `--option` flag), but you should fully spell them out
	when writing your scripts; later versions of Git may introduce a
	new option whose name shares the same prefix, e.g. `--optimize`,
	to make a short prefix that used to be unique no longer unique.


	ENHANCED OPTION PARSER
	----------------------
	From the Git 1.5.4 series and further, many Git commands (not all of them at the
	time of the writing though) come with an enhanced option parser.

	Here is a list of the facilities provided by this option parser.


	Magic Options
	~~~~~~~~~~~~~
	Commands which have the enhanced option parser activated all understand a
	couple of magic command-line options:

	-h::
	gives a pretty printed usage of the command.
	+
	---------------------------------------------
	$ git describe -h
	usage: git describe [<options>] <commit-ish>*
	or: git describe [<options>] --dirty

	--contains find the tag that comes after the commit
	--debug debug search strategy on stderr
	--all use any ref
	--tags use any tag, even unannotated
	--long always use long format
	--abbrev[=<n>] use <n> digits to display SHA-1s
	---------------------------------------------
	+
	Note that some subcommand (e.g. `git grep`) may behave differently
	when there are things on the command line other than `-h`, but `git
	subcmd -h` without anything else on the command line is meant to
	consistently give the usage.

	--help-all::
	Some Git commands take options that are only used for plumbing or that
	are deprecated, and such options are hidden from the default usage. This
	option gives the full list of options.


	Negating options
	~~~~~~~~~~~~~~~~
	Options with long option names can be negated by prefixing `--no-`. For
	example, `git branch` has the option `--track` which is 'on' by default. You
	can use `--no-track` to override that behaviour. The same goes for `--color`
	and `--no-color`.


	Options trump configuration and environment
	~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

	When there is a configuration variable or an environment variable
	that tweak the behaviour of an aspect of a Git command, and also a
	command line option that tweaks the same, the command line option
	overrides what the configuration and/or environment variable say.

	For example, the `user.name` configuration variable is used to
	specify the human-readable name used by the `git commit` command to
	record the author and the committer name in a newly created commit.
	The `GIT_AUTHOR_NAME` environment variable, if set, takes precedence
	when deciding what author name to record. The `--author=<author>`
	command line option of the `git commit` command, when given, takes
	precedence over these two sources of information.


	Aggregating short options
	~~~~~~~~~~~~~~~~~~~~~~~~~
	Commands that support the enhanced option parser allow you to aggregate short
	options. This means that you can for example use `git rm -rf` or
	`git clean -fdx`.


	Abbreviating long options
	~~~~~~~~~~~~~~~~~~~~~~~~~
	Commands that support the enhanced option parser accepts unique
	prefix of a long option as if it is fully spelled out, but use this
	with a caution. For example, `git commit --amen` behaves as if you
	typed `git commit --amend`, but that is true only until a later version
	of Git introduces another option that shares the same prefix,
	e.g. `git commit --amenity` option.


	Separating argument from the option
	~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
	You can write the mandatory option parameter to an option as a separate
	word on the command line. That means that all the following uses work:

	----------------------------
	$ git foo --long-opt=Arg
	$ git foo --long-opt Arg
	$ git foo -oArg
	$ git foo -o Arg
	----------------------------

	However, this is NOT allowed for switches with an optional value, where the
	'stuck' form must be used:

	----------------------------
	$ git describe --abbrev HEAD # correct
	$ git describe --abbrev=10 HEAD # correct
	$ git describe --abbrev 10 HEAD # NOT WHAT YOU MEANT
	----------------------------


	Magic filename options
	~~~~~~~~~~~~~~~~~~~~~~
	Options that take a filename allow a prefix `:(optional)`. For example:

	----------------------------
	git commit -F :(optional)COMMIT_EDITMSG
	# if COMMIT_EDITMSG does not exist, the above is equivalent to
	git commit
	----------------------------

	Like with configuration values, if the named file is missing Git behaves as if
	the option was not given at all. See "Values" in linkgit:git-config[1].

	NOTES ON FREQUENTLY CONFUSED OPTIONS
	------------------------------------

	Many commands that can work on files in the working tree
	and/or in the index can take `--cached` and/or `--index`
	options. Sometimes people incorrectly think that, because
	the index was originally called cache, these two are
	synonyms. They are not -- these two options mean very
	different things.

	* The `--cached` option is used to ask a command that
	usually works on files in the working tree to only work
	with the index. For example, `git grep`, when used
	without a commit to specify from which commit to look for
	strings in, usually works on files in the working tree,
	but with the `--cached` option, it looks for strings in
	the index.

	* The `--index` option is used to ask a command that
	usually works on files in the working tree to also
	affect the index. For example, `git stash apply` usually
	merges changes recorded in a stash entry to the working tree,
	but with the `--index` option, it also merges changes to
	the index as well.

	`git apply` command can be used with `--cached` and
	`--index` (but not at the same time). Usually the command
	only affects the files in the working tree, but with
	`--index`, it patches both the files and their index
	entries, and with `--cached`, it modifies only the index
	entries.

	See also https://lore.kernel.org/git/7v64clg5u9.fsf@assigned-by-dhcp.cox.net/ and
	https://lore.kernel.org/git/7vy7ej9g38.fsf@gitster.siamese.dyndns.org/ for further
	information.

	Some other commands that also work on files in the working tree and/or
	in the index can take `--staged` and/or `--worktree`.

	* `--staged` is exactly like `--cached`, which is used to ask a
	command to only work on the index, not the working tree.

	* `--worktree` is the opposite, to ask a command to work on the
	working tree only, not the index.

	* The two options can be specified together to ask a command to work
	on both the index and the working tree.

	GIT
	---
	Part of the linkgit:git[1] suite