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 When writing a script that is expected to handle random user-input, it is
  42 a good practice to make it explicit which arguments are which by placing
  43 disambiguating `--` at appropriate places.
  44
  45  * Many commands allow wildcards in paths, but you need to protect
  46    them from getting globbed by the shell.  These two mean different
  47    things:
  48 +
  49 --------------------------------
  50 $ git checkout -- *.c
  51 $ git checkout -- \*.c
  52 --------------------------------
  53 +
  54 The former lets your shell expand the fileglob, and you are asking
  55 the dot-C files in your working tree to be overwritten with the version
  56 in the index.  The latter passes the `*.c` to Git, and you are asking
  57 the paths in the index that match the pattern to be checked out to your
  58 working tree.  After running `git add hello.c; rm hello.c`, you will _not_
  59 see `hello.c` in your working tree with the former, but with the latter
  60 you will.
  61
  62 Here are the rules regarding the "flags" that you should follow when you are
  63 scripting git:
  64
  65  * it's preferred to use the non dashed form of git commands, which means that
  66    you should prefer `git foo` to `git-foo`.
  67
  68  * splitting short options to separate words (prefer `git foo -a -b`
  69    to `git foo -ab`, the latter may not even work).
  70
  71  * when a command line option takes an argument, use the 'sticked' form.  In
  72    other words, write `git foo -oArg` instead of `git foo -o Arg` for short
  73    options, and `git foo --long-opt=Arg` instead of `git foo --long-opt Arg`
  74    for long options.  An option that takes optional option-argument must be
  75    written in the 'sticked' form.
  76
  77  * when you give a revision parameter to a command, make sure the parameter is
  78    not ambiguous with a name of a file in the work tree.  E.g. do not write
  79    `git log -1 HEAD` but write `git log -1 HEAD --`; the former will not work
  80    if you happen to have a file called `HEAD` in the work tree.
  81
  82  * many commands allow a long option "--option" to be abbreviated
  83    only to their unique prefix (e.g. if there is no other option
  84    whose name begins with "opt", you may be able to spell "--opt" to
  85    invoke the "--option" flag), but you should fully spell them out
  86    when writing your scripts; later versions of Git may introduce a
  87    new option whose name shares the same prefix, e.g. "--optimize",
  88    to make a short prefix that used to be unique no longer unique.
  89
  90
  91 ENHANCED OPTION PARSER
  92 ----------------------
  93 From the git 1.5.4 series and further, many git commands (not all of them at the
  94 time of the writing though) come with an enhanced option parser.
  95
  96 Here is an exhaustive list of the facilities provided by this option parser.
  97
  98
  99 Magic Options
 100 ~~~~~~~~~~~~~
 101 Commands which have the enhanced option parser activated all understand a
 102 couple of magic command line options:
 103
 104 -h::
 105         gives a pretty printed usage of the command.
 106 +
 107 ---------------------------------------------
 108 $ git describe -h
 109 usage: git describe [options] <committish>*
 110
 111     --contains            find the tag that comes after the commit
 112     --debug               debug search strategy on stderr
 113     --all                 use any ref in .git/refs
 114     --tags                use any tag in .git/refs/tags
 115     --abbrev [<n>]        use <n> digits to display SHA-1s
 116     --candidates <n>      consider <n> most recent tags (default: 10)
 117 ---------------------------------------------
 118
 119 --help-all::
 120         Some git commands take options that are only used for plumbing or that
 121         are deprecated, and such options are hidden from the default usage. This
 122         option gives the full list of options.
 123
 124
 125 Negating options
 126 ~~~~~~~~~~~~~~~~
 127 Options with long option names can be negated by prefixing `--no-`. For
 128 example, `git branch` has the option `--track` which is 'on' by default. You
 129 can use `--no-track` to override that behaviour. The same goes for `--color`
 130 and `--no-color`.
 131
 132
 133 Aggregating short options
 134 ~~~~~~~~~~~~~~~~~~~~~~~~~
 135 Commands that support the enhanced option parser allow you to aggregate short
 136 options. This means that you can for example use `git rm -rf` or
 137 `git clean -fdx`.
 138
 139
 140 Separating argument from the option
 141 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 142 You can write the mandatory option parameter to an option as a separate
 143 word on the command line.  That means that all the following uses work:
 144
 145 ----------------------------
 146 $ git foo --long-opt=Arg
 147 $ git foo --long-opt Arg
 148 $ git foo -oArg
 149 $ git foo -o Arg
 150 ----------------------------
 151
 152 However, this is *NOT* allowed for switches with an optional value, where the
 153 'sticked' form must be used:
 154 ----------------------------
 155 $ git describe --abbrev HEAD     # correct
 156 $ git describe --abbrev=10 HEAD  # correct
 157 $ git describe --abbrev 10 HEAD  # NOT WHAT YOU MEANT
 158 ----------------------------
 159
 160
 161 NOTES ON FREQUENTLY CONFUSED OPTIONS
 162 ------------------------------------
 163
 164 Many commands that can work on files in the working tree
 165 and/or in the index can take `--cached` and/or `--index`
 166 options.  Sometimes people incorrectly think that, because
 167 the index was originally called cache, these two are
 168 synonyms.  They are *not* -- these two options mean very
 169 different things.
 170
 171  * The `--cached` option is used to ask a command that
 172    usually works on files in the working tree to *only* work
 173    with the index.  For example, `git grep`, when used
 174    without a commit to specify from which commit to look for
 175    strings in, usually works on files in the working tree,
 176    but with the `--cached` option, it looks for strings in
 177    the index.
 178
 179  * The `--index` option is used to ask a command that
 180    usually works on files in the working tree to *also*
 181    affect the index.  For example, `git stash apply` usually
 182    merges changes recorded in a stash to the working tree,
 183    but with the `--index` option, it also merges changes to
 184    the index as well.
 185
 186 `git apply` command can be used with `--cached` and
 187 `--index` (but not at the same time).  Usually the command
 188 only affects the files in the working tree, but with
 189 `--index`, it patches both the files and their index
 190 entries, and with `--cached`, it modifies only the index
 191 entries.
 192
 193 See also http://marc.info/?l=git&m=116563135620359 and
 194 http://marc.info/?l=git&m=119150393620273 for further
 195 information.
 196
 197 GIT
 198 ---
 199 Part of the linkgit:git[1] suite