Documentation/git-submodule.txt: Add Description section
[git/git.git] / Documentation / git-submodule.txt
1 git-submodule(1)
2 ================
3
4 NAME
5 ----
6 git-submodule - Initialize, update or inspect submodules
7
8
9 SYNOPSIS
10 --------
11 [verse]
12 'git submodule' [--quiet] add [-b branch] [--] <repository> <path>
13 'git submodule' [--quiet] status [--cached] [--] [<path>...]
14 'git submodule' [--quiet] init [--] [<path>...]
15 'git submodule' [--quiet] update [--init] [--] [<path>...]
16 'git submodule' [--quiet] summary [--summary-limit <n>] [commit] [--] [<path>...]
17
18
19 DESCRIPTION
20 -----------
21 Submodules are a special kind of tree entries which refer to a particular tree
22 state in another repository. The tree entry describes
23 the existence of a submodule with the given name and the exact revision that
24 should be used, while an entry in `.gitmodules` file gives the location of
25 the repository.
26
27 When checked out, submodules will maintain their own independent repositories
28 within their directories; the only link between the submodule and the "parent
29 project" is the tree entry within the parent project mentioned above.
30
31 This command will manage the tree entries and contents of the gitmodules file
32 for you, as well as inspecting the status of your submodules and updating them.
33 When adding a new submodule to the tree, the 'add' subcommand is to be used.
34 However, when pulling a tree containing submodules, these will not be checked
35 out by default; the 'init' and 'update' subcommands will maintain submodules
36 checked out and at appropriate revision in your working tree. You can inspect
37 the current status of your submodules using the 'submodule' subcommand and get
38 an overview of changes 'update' would perform using the 'summary' subcommand.
39
40
41 COMMANDS
42 --------
43 add::
44 Add the given repository as a submodule at the given path
45 to the changeset to be committed next to the current
46 project: the current project is termed termed the "superproject".
47 +
48 This requires two arguments: <repository> and <path>.
49 +
50 <repository> is the URL of the new submodule's origin repository.
51 This may be either an absolute URL, or (if it begins with ./
52 or ../), the location relative to the superproject's origin
53 repository.
54 +
55 <path> is the relative location for the cloned submodule to
56 exist in the superproject. If <path> does not exist, then the
57 submodule is created by cloning from the named URL. If <path> does
58 exist and is already a valid git repository, then this is added
59 to the changeset without cloning. This second form is provided
60 to ease creating a new submodule from scratch, and presumes
61 the user will later push the submodule to the given URL.
62 +
63 In either case, the given URL is recorded into .gitmodules for
64 use by subsequent users cloning the superproject. If the URL is
65 given relative to the superproject's repository, the presumption
66 is the superproject and submodule repositories will be kept
67 together in the same relative location, and only the
68 superproject's URL need be provided: git-submodule will correctly
69 locate the submodule using the relative URL in .gitmodules.
70
71 status::
72 Show the status of the submodules. This will print the SHA-1 of the
73 currently checked out commit for each submodule, along with the
74 submodule path and the output of 'git-describe' for the
75 SHA-1. Each SHA-1 will be prefixed with `-` if the submodule is not
76 initialized and `+` if the currently checked out submodule commit
77 does not match the SHA-1 found in the index of the containing
78 repository. This command is the default command for 'git-submodule'.
79
80 init::
81 Initialize the submodules, i.e. register in .git/config each submodule
82 name and url found in .gitmodules. The key used in .git/config is
83 `submodule.$name.url`. This command does not alter existing information
84 in .git/config.
85
86 update::
87 Update the registered submodules, i.e. clone missing submodules and
88 checkout the commit specified in the index of the containing repository.
89 This will make the submodules HEAD be detached.
90 +
91 If the submodule is not yet initialized, and you just want to use the
92 setting as stored in .gitmodules, you can automatically initialize the
93 submodule with the --init option.
94
95 summary::
96 Show commit summary between the given commit (defaults to HEAD) and
97 working tree/index. For a submodule in question, a series of commits
98 in the submodule between the given super project commit and the
99 index or working tree (switched by --cached) are shown.
100
101 OPTIONS
102 -------
103 -q::
104 --quiet::
105 Only print error messages.
106
107 -b::
108 --branch::
109 Branch of repository to add as submodule.
110
111 --cached::
112 This option is only valid for status and summary commands. These
113 commands typically use the commit found in the submodule HEAD, but
114 with this option, the commit stored in the index is used instead.
115
116 -n::
117 --summary-limit::
118 This option is only valid for the summary command.
119 Limit the summary size (number of commits shown in total).
120 Giving 0 will disable the summary; a negative number means unlimited
121 (the default). This limit only applies to modified submodules. The
122 size is always limited to 1 for added/deleted/typechanged submodules.
123
124 <path>::
125 Path to submodule(s). When specified this will restrict the command
126 to only operate on the submodules found at the specified paths.
127 (This argument is required with add).
128
129 FILES
130 -----
131 When initializing submodules, a .gitmodules file in the top-level directory
132 of the containing repository is used to find the url of each submodule.
133 This file should be formatted in the same way as `$GIT_DIR/config`. The key
134 to each submodule url is "submodule.$name.url". See linkgit:gitmodules[5]
135 for details.
136
137
138 AUTHOR
139 ------
140 Written by Lars Hjemli <hjemli@gmail.com>
141
142 GIT
143 ---
144 Part of the linkgit:git[1] suite