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 gave 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 ambiguity 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 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 asking 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  * It's preferred to use the non-dashed form of Git commands, which means that
  85    you should prefer `git foo` to `git-foo`.
  86
  87  * Splitting short options to separate words (prefer `git foo -a -b`
  88    to `git foo -ab`, the latter may not even work).
  89
  90  * When a command-line option takes an argument, use the 'stuck' form.  In
  91    other words, write `git foo -oArg` instead of `git foo -o Arg` for short
  92    options, and `git foo --long-opt=Arg` instead of `git foo --long-opt Arg`
  93    for long options.  An option that takes optional option-argument must be
  94    written in the 'stuck' form.
  95
  96  * When you give a revision parameter to a command, make sure the parameter is
  97    not ambiguous with a name of a file in the work tree.  E.g. do not write
  98    `git log -1 HEAD` but write `git log -1 HEAD --`; the former will not work
  99    if you happen to have a file called `HEAD` in the work tree.
 100
 101  * Many commands allow a long option `--option` to be abbreviated
 102    only to their unique prefix (e.g. if there is no other option
 103    whose name begins with `opt`, you may be able to spell `--opt` to
 104    invoke the `--option` flag), but you should fully spell them out
 105    when writing your scripts; later versions of Git may introduce a
 106    new option whose name shares the same prefix, e.g. `--optimize`,
 107    to make a short prefix that used to be unique no longer unique.
 108
 109
 110 ENHANCED OPTION PARSER
 111 ----------------------
 112 From the Git 1.5.4 series and further, many Git commands (not all of them at the
 113 time of the writing though) come with an enhanced option parser.
 114
 115 Here is a list of the facilities provided by this option parser.
 116
 117
 118 Magic Options
 119 ~~~~~~~~~~~~~
 120 Commands which have the enhanced option parser activated all understand a
 121 couple of magic command-line options:
 122
 123 -h::
 124         gives a pretty printed usage of the command.
 125 +
 126 ---------------------------------------------
 127 $ git describe -h
 128 usage: git describe [<options>] <commit-ish>*
 129    or: git describe [<options>] --dirty
 130
 131     --contains            find the tag that comes after the commit
 132     --debug               debug search strategy on stderr
 133     --all                 use any ref
 134     --tags                use any tag, even unannotated
 135     --long                always use long format
 136     --abbrev[=<n>]        use <n> digits to display SHA-1s
 137 ---------------------------------------------
 138 +
 139 Note that some subcommand (e.g. `git grep`) may behave differently
 140 when there are things on the command line other than `-h`, but `git
 141 subcmd -h` without anything else on the command line is meant to
 142 consistently give the usage.
 143
 144 --help-all::
 145         Some Git commands take options that are only used for plumbing or that
 146         are deprecated, and such options are hidden from the default usage. This
 147         option gives the full list of options.
 148
 149
 150 Negating options
 151 ~~~~~~~~~~~~~~~~
 152 Options with long option names can be negated by prefixing `--no-`. For
 153 example, `git branch` has the option `--track` which is 'on' by default. You
 154 can use `--no-track` to override that behaviour. The same goes for `--color`
 155 and `--no-color`.
 156
 157
 158 Aggregating short options
 159 ~~~~~~~~~~~~~~~~~~~~~~~~~
 160 Commands that support the enhanced option parser allow you to aggregate short
 161 options. This means that you can for example use `git rm -rf` or
 162 `git clean -fdx`.
 163
 164
 165 Abbreviating long options
 166 ~~~~~~~~~~~~~~~~~~~~~~~~~
 167 Commands that support the enhanced option parser accepts unique
 168 prefix of a long option as if it is fully spelled out, but use this
 169 with a caution.  For example, `git commit --amen` behaves as if you
 170 typed `git commit --amend`, but that is true only until a later version
 171 of Git introduces another option that shares the same prefix,
 172 e.g. `git commit --amenity` option.
 173
 174
 175 Separating argument from the option
 176 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 177 You can write the mandatory option parameter to an option as a separate
 178 word on the command line.  That means that all the following uses work:
 179
 180 ----------------------------
 181 $ git foo --long-opt=Arg
 182 $ git foo --long-opt Arg
 183 $ git foo -oArg
 184 $ git foo -o Arg
 185 ----------------------------
 186
 187 However, this is *NOT* allowed for switches with an optional value, where the
 188 'stuck' form must be used:
 189 ----------------------------
 190 $ git describe --abbrev HEAD     # correct
 191 $ git describe --abbrev=10 HEAD  # correct
 192 $ git describe --abbrev 10 HEAD  # NOT WHAT YOU MEANT
 193 ----------------------------
 194
 195
 196 NOTES ON FREQUENTLY CONFUSED OPTIONS
 197 ------------------------------------
 198
 199 Many commands that can work on files in the working tree
 200 and/or in the index can take `--cached` and/or `--index`
 201 options.  Sometimes people incorrectly think that, because
 202 the index was originally called cache, these two are
 203 synonyms.  They are *not* -- these two options mean very
 204 different things.
 205
 206  * The `--cached` option is used to ask a command that
 207    usually works on files in the working tree to *only* work
 208    with the index.  For example, `git grep`, when used
 209    without a commit to specify from which commit to look for
 210    strings in, usually works on files in the working tree,
 211    but with the `--cached` option, it looks for strings in
 212    the index.
 213
 214  * The `--index` option is used to ask a command that
 215    usually works on files in the working tree to *also*
 216    affect the index.  For example, `git stash apply` usually
 217    merges changes recorded in a stash entry to the working tree,
 218    but with the `--index` option, it also merges changes to
 219    the index as well.
 220
 221 `git apply` command can be used with `--cached` and
 222 `--index` (but not at the same time).  Usually the command
 223 only affects the files in the working tree, but with
 224 `--index`, it patches both the files and their index
 225 entries, and with `--cached`, it modifies only the index
 226 entries.
 227
 228 See also https://lore.kernel.org/git/7v64clg5u9.fsf@assigned-by-dhcp.cox.net/ and
 229 https://lore.kernel.org/git/7vy7ej9g38.fsf@gitster.siamese.dyndns.org/ for further
 230 information.
 231
 232 Some other commands that also work on files in the working tree and/or
 233 in the index can take `--staged` and/or `--worktree`.
 234
 235 * `--staged` is exactly like `--cached`, which is used to ask a
 236   command to only work on the index, not the working tree.
 237
 238 * `--worktree` is the opposite, to ask a command to work on the
 239   working tree only, not the index.
 240
 241 * The two options can be specified together to ask a command to work
 242   on both the index and the working tree.
 243
 244 GIT
 245 ---
 246 Part of the linkgit:git[1] suite