Documentation/gitcli.txt

   1 gitcli(7)
   2 =========
   3
   4 NAME
   5 ----
   6 gitcli - Git command-line interface and conventions
   7
   8 SYNOPSIS
   9 --------
  10 gitcli
  11
  12
  13 DESCRIPTION
  14 -----------
  15
  16 This manual describes the convention used throughout Git CLI.
  17
  18 Many commands take revisions (most often "commits", but sometimes
  19 "tree-ish", depending on the context and command) and paths as their
  20 arguments.  Here are the rules:
  21
  22  * Options come first and then args.
  23     A subcommand may take dashed options (which may take their own
  24     arguments, e.g. "--max-parents 2") and arguments.  You SHOULD
  25     give dashed options first and then arguments.  Some commands may
  26     accept dashed options after you have already given non-option
  27     arguments (which may make the command ambiguous), but you should
  28     not rely on it (because eventually we may find a way to fix
  29     these ambiguities by enforcing the "options then args" rule).
  30
  31  * Revisions come first and then paths.
  32    E.g. in `git diff v1.0 v2.0 arch/x86 include/asm-x86`,
  33    `v1.0` and `v2.0` are revisions and `arch/x86` and `include/asm-x86`
  34    are paths.
  35
  36  * When an argument can be misunderstood as either a revision or a path,
  37    they can be disambiguated by placing `--` between them.
  38    E.g. `git diff -- HEAD` is, "I have a file called HEAD in my work
  39    tree.  Please show changes between the version I staged in the index
  40    and what I have in the work tree for that file", not "show the difference
  41    between the HEAD commit and the work tree as a whole".  You can say
  42    `git diff HEAD --` to ask for the latter.
  43
  44  * Without disambiguating `--`, Git makes a reasonable guess, but errors
  45    out and asks you to disambiguate when ambiguous.  E.g. if you have a
  46    file called HEAD in your work tree, `git diff HEAD` is ambiguous, and
  47    you have to say either `git diff HEAD --` or `git diff -- HEAD` to
  48    disambiguate.
  49
  50  * Because `--` disambiguates revisions and paths in some commands, it
  51    cannot be used for those commands to separate options and revisions.
  52    You can use `--end-of-options` for this (it also works for commands
  53    that do not distinguish between revisions in paths, in which case it
  54    is simply an alias for `--`).
  55 +
  56 When writing a script that is expected to handle random user-input, it is
  57 a good practice to make it explicit which arguments are which by placing
  58 disambiguating `--` at appropriate places.
  59
  60  * Many commands allow wildcards in paths, but you need to protect
  61    them from getting globbed by the shell.  These two mean different
  62    things:
  63 +
  64 --------------------------------
  65 $ git restore *.c
  66 $ git restore \*.c
  67 --------------------------------
  68 +
  69 The former lets your shell expand the fileglob, and you are asking
  70 the dot-C files in your working tree to be overwritten with the version
  71 in the index.  The latter passes the `*.c` to Git, and you are asking
  72 the paths in the index that match the pattern to be checked out to your
  73 working tree.  After running `git add hello.c; rm hello.c`, you will _not_
  74 see `hello.c` in your working tree with the former, but with the latter
  75 you will.
  76
  77  * Just as the filesystem '.' (period) refers to the current directory,
  78    using a '.' as a repository name in Git (a dot-repository) is a relative
  79    path and means your current repository.
  80
  81 Here are the rules regarding the "flags" that you should follow when you are
  82 scripting Git:
  83
  84  * Splitting short options to separate words (prefer `git foo -a -b`
  85    to `git foo -ab`, the latter may not even work).
  86
  87  * When a command-line option takes an argument, use the 'stuck' form.  In
  88    other words, write `git foo -oArg` instead of `git foo -o Arg` for short
  89    options, and `git foo --long-opt=Arg` instead of `git foo --long-opt Arg`
  90    for long options.  An option that takes optional option-argument must be
  91    written in the 'stuck' form.
  92
  93  * When you give a revision parameter to a command, make sure the parameter is
  94    not ambiguous with a name of a file in the work tree.  E.g. do not write
  95    `git log -1 HEAD` but write `git log -1 HEAD --`; the former will not work
  96    if you happen to have a file called `HEAD` in the work tree.
  97
  98  * Many commands allow a long option `--option` to be abbreviated
  99    only to their unique prefix (e.g. if there is no other option
 100    whose name begins with `opt`, you may be able to spell `--opt` to
 101    invoke the `--option` flag), but you should fully spell them out
 102    when writing your scripts; later versions of Git may introduce a
 103    new option whose name shares the same prefix, e.g. `--optimize`,
 104    to make a short prefix that used to be unique no longer unique.
 105
 106
 107 ENHANCED OPTION PARSER
 108 ----------------------
 109 From the Git 1.5.4 series and further, many Git commands (not all of them at the
 110 time of the writing though) come with an enhanced option parser.
 111
 112 Here is a list of the facilities provided by this option parser.
 113
 114
 115 Magic Options
 116 ~~~~~~~~~~~~~
 117 Commands which have the enhanced option parser activated all understand a
 118 couple of magic command-line options:
 119
 120 -h::
 121         gives a pretty printed usage of the command.
 122 +
 123 ---------------------------------------------
 124 $ git describe -h
 125 usage: git describe [<options>] <commit-ish>*
 126    or: git describe [<options>] --dirty
 127
 128     --contains            find the tag that comes after the commit
 129     --debug               debug search strategy on stderr
 130     --all                 use any ref
 131     --tags                use any tag, even unannotated
 132     --long                always use long format
 133     --abbrev[=<n>]        use <n> digits to display SHA-1s
 134 ---------------------------------------------
 135 +
 136 Note that some subcommand (e.g. `git grep`) may behave differently
 137 when there are things on the command line other than `-h`, but `git
 138 subcmd -h` without anything else on the command line is meant to
 139 consistently give the usage.
 140
 141 --help-all::
 142         Some Git commands take options that are only used for plumbing or that
 143         are deprecated, and such options are hidden from the default usage. This
 144         option gives the full list of options.
 145
 146
 147 Negating options
 148 ~~~~~~~~~~~~~~~~
 149 Options with long option names can be negated by prefixing `--no-`. For
 150 example, `git branch` has the option `--track` which is 'on' by default. You
 151 can use `--no-track` to override that behaviour. The same goes for `--color`
 152 and `--no-color`.
 153
 154
 155 Aggregating short options
 156 ~~~~~~~~~~~~~~~~~~~~~~~~~
 157 Commands that support the enhanced option parser allow you to aggregate short
 158 options. This means that you can for example use `git rm -rf` or
 159 `git clean -fdx`.
 160
 161
 162 Abbreviating long options
 163 ~~~~~~~~~~~~~~~~~~~~~~~~~
 164 Commands that support the enhanced option parser accepts unique
 165 prefix of a long option as if it is fully spelled out, but use this
 166 with a caution.  For example, `git commit --amen` behaves as if you
 167 typed `git commit --amend`, but that is true only until a later version
 168 of Git introduces another option that shares the same prefix,
 169 e.g. `git commit --amenity` option.
 170
 171
 172 Separating argument from the option
 173 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 174 You can write the mandatory option parameter to an option as a separate
 175 word on the command line.  That means that all the following uses work:
 176
 177 ----------------------------
 178 $ git foo --long-opt=Arg
 179 $ git foo --long-opt Arg
 180 $ git foo -oArg
 181 $ git foo -o Arg
 182 ----------------------------
 183
 184 However, this is *NOT* allowed for switches with an optional value, where the
 185 'stuck' form must be used:
 186 ----------------------------
 187 $ git describe --abbrev HEAD     # correct
 188 $ git describe --abbrev=10 HEAD  # correct
 189 $ git describe --abbrev 10 HEAD  # NOT WHAT YOU MEANT
 190 ----------------------------
 191
 192
 193 NOTES ON FREQUENTLY CONFUSED OPTIONS
 194 ------------------------------------
 195
 196 Many commands that can work on files in the working tree
 197 and/or in the index can take `--cached` and/or `--index`
 198 options.  Sometimes people incorrectly think that, because
 199 the index was originally called cache, these two are
 200 synonyms.  They are *not* -- these two options mean very
 201 different things.
 202
 203  * The `--cached` option is used to ask a command that
 204    usually works on files in the working tree to *only* work
 205    with the index.  For example, `git grep`, when used
 206    without a commit to specify from which commit to look for
 207    strings in, usually works on files in the working tree,
 208    but with the `--cached` option, it looks for strings in
 209    the index.
 210
 211  * The `--index` option is used to ask a command that
 212    usually works on files in the working tree to *also*
 213    affect the index.  For example, `git stash apply` usually
 214    merges changes recorded in a stash entry to the working tree,
 215    but with the `--index` option, it also merges changes to
 216    the index as well.
 217
 218 `git apply` command can be used with `--cached` and
 219 `--index` (but not at the same time).  Usually the command
 220 only affects the files in the working tree, but with
 221 `--index`, it patches both the files and their index
 222 entries, and with `--cached`, it modifies only the index
 223 entries.
 224
 225 See also https://lore.kernel.org/git/7v64clg5u9.fsf@assigned-by-dhcp.cox.net/ and
 226 https://lore.kernel.org/git/7vy7ej9g38.fsf@gitster.siamese.dyndns.org/ for further
 227 information.
 228
 229 Some other commands that also work on files in the working tree and/or
 230 in the index can take `--staged` and/or `--worktree`.
 231
 232 * `--staged` is exactly like `--cached`, which is used to ask a
 233   command to only work on the index, not the working tree.
 234
 235 * `--worktree` is the opposite, to ask a command to work on the
 236   working tree only, not the index.
 237
 238 * The two options can be specified together to ask a command to work
 239   on both the index and the working tree.
 240
 241 GIT
 242 ---
 243 Part of the linkgit:git[1] suite