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