1git-submodule(1) 2================ 3 4NAME 5---- 6git-submodule - Initialize, update or inspect submodules 7 8 9SYNOPSIS 10-------- 11[verse] 12'git submodule' [--quiet] add [-b branch] 13 [--reference <repository>] [--] <repository> <path> 14'git submodule' [--quiet] status [--cached] [--] [<path>...] 15'git submodule' [--quiet] init [--] [<path>...] 16'git submodule' [--quiet] update [--init] [-N|--no-fetch] [--rebase] 17 [--reference <repository>] [--merge] [--] [<path>...] 18'git submodule' [--quiet] summary [--cached] [--summary-limit <n>] [commit] [--] [<path>...] 19'git submodule' [--quiet] foreach <command> 20'git submodule' [--quiet] sync [--] [<path>...] 21 22 23DESCRIPTION 24----------- 25Submodules allow foreign repositories to be embedded within 26a dedicated subdirectory of the source tree, always pointed 27at a particular commit. 28 29They are not to be confused with remotes, which are meant mainly 30for branches of the same project; submodules are meant for 31different projects you would like to make part of your source tree, 32while the history of the two projects still stays completely 33independent and you cannot modify the contents of the submodule 34from within the main project. 35If you want to merge the project histories and want to treat the 36aggregated whole as a single project from then on, you may want to 37add a remote for the other project and use the 'subtree' merge strategy, 38instead of treating the other project as a submodule. Directories 39that come from both projects can be cloned and checked out as a whole 40if you choose to go that route. 41 42Submodules are composed from a so-called `gitlink` tree entry 43in the main repository that refers to a particular commit object 44within the inner repository that is completely separate. 45A record in the `.gitmodules` file at the root of the source 46tree assigns a logical name to the submodule and describes 47the default URL the submodule shall be cloned from. 48The logical name can be used for overriding this URL within your 49local repository configuration (see 'submodule init'). 50 51This command will manage the tree entries and contents of the 52gitmodules file for you, as well as inspect the status of your 53submodules and update them. 54When adding a new submodule to the tree, the 'add' subcommand 55is to be used. However, when pulling a tree containing submodules, 56these will not be checked out by default; 57the 'init' and 'update' subcommands will maintain submodules 58checked out and at appropriate revision in your working tree. 59You can briefly inspect the up-to-date status of your submodules 60using the 'status' subcommand and get a detailed overview of the 61difference between the index and checkouts using the 'summary' 62subcommand. 63 64 65COMMANDS 66-------- 67add:: 68 Add the given repository as a submodule at the given path 69 to the changeset to be committed next to the current 70 project: the current project is termed the "superproject". 71+ 72This requires two arguments: <repository> and <path>. 73+ 74<repository> is the URL of the new submodule's origin repository. 75This may be either an absolute URL, or (if it begins with ./ 76or ../), the location relative to the superproject's origin 77repository. 78+ 79<path> is the relative location for the cloned submodule to 80exist in the superproject. If <path> does not exist, then the 81submodule is created by cloning from the named URL. If <path> does 82exist and is already a valid git repository, then this is added 83to the changeset without cloning. This second form is provided 84to ease creating a new submodule from scratch, and presumes 85the user will later push the submodule to the given URL. 86+ 87In either case, the given URL is recorded into .gitmodules for 88use by subsequent users cloning the superproject. If the URL is 89given relative to the superproject's repository, the presumption 90is the superproject and submodule repositories will be kept 91together in the same relative location, and only the 92superproject's URL needs to be provided: git-submodule will correctly 93locate the submodule using the relative URL in .gitmodules. 94 95status:: 96 Show the status of the submodules. This will print the SHA-1 of the 97 currently checked out commit for each submodule, along with the 98 submodule path and the output of 'git-describe' for the 99 SHA-1. Each SHA-1 will be prefixed with `-` if the submodule is not 100 initialized and `+` if the currently checked out submodule commit 101 does not match the SHA-1 found in the index of the containing 102 repository. This command is the default command for 'git-submodule'. 103 104init:: 105 Initialize the submodules, i.e. register each submodule name 106 and url found in .gitmodules into .git/config. 107 The key used in .git/config is `submodule.$name.url`. 108 This command does not alter existing information in .git/config. 109 You can then customize the submodule clone URLs in .git/config 110 for your local setup and proceed to 'git submodule update'; 111 you can also just use 'git submodule update --init' without 112 the explicit 'init' step if you do not intend to customize 113 any submodule locations. 114 115update:: 116 Update the registered submodules, i.e. clone missing submodules and 117 checkout the commit specified in the index of the containing repository. 118 This will make the submodules HEAD be detached unless '--rebase' or 119 '--merge' is specified or the key `submodule.$name.update` is set to 120 `rebase` or `merge`. 121+ 122If the submodule is not yet initialized, and you just want to use the 123setting as stored in .gitmodules, you can automatically initialize the 124submodule with the --init option. 125 126summary:: 127 Show commit summary between the given commit (defaults to HEAD) and 128 working tree/index. For a submodule in question, a series of commits 129 in the submodule between the given super project commit and the 130 index or working tree (switched by --cached) are shown. 131 132foreach:: 133 Evaluates an arbitrary shell command in each checked out submodule. 134 The command has access to the variables $name, $path and $sha1: 135 $name is the name of the relevant submodule section in .gitmodules, 136 $path is the name of the submodule directory relative to the 137 superproject, and $sha1 is the commit as recorded in the superproject. 138 Any submodules defined in the superproject but not checked out are 139 ignored by this command. Unless given --quiet, foreach prints the name 140 of each submodule before evaluating the command. 141 A non-zero return from the command in any submodule causes 142 the processing to terminate. This can be overridden by adding '|| :' 143 to the end of the command. 144+ 145As an example, +git submodule foreach \'echo $path {backtick}git 146rev-parse HEAD{backtick}'+ will show the path and currently checked out 147commit for each submodule. 148 149sync:: 150 Synchronizes submodules' remote URL configuration setting 151 to the value specified in .gitmodules. This is useful when 152 submodule URLs change upstream and you need to update your local 153 repositories accordingly. 154+ 155"git submodule sync" synchronizes all submodules while 156"git submodule sync -- A" synchronizes submodule "A" only. 157 158OPTIONS 159------- 160-q:: 161--quiet:: 162 Only print error messages. 163 164-b:: 165--branch:: 166 Branch of repository to add as submodule. 167 168--cached:: 169 This option is only valid for status and summary commands. These 170 commands typically use the commit found in the submodule HEAD, but 171 with this option, the commit stored in the index is used instead. 172 173-n:: 174--summary-limit:: 175 This option is only valid for the summary command. 176 Limit the summary size (number of commits shown in total). 177 Giving 0 will disable the summary; a negative number means unlimited 178 (the default). This limit only applies to modified submodules. The 179 size is always limited to 1 for added/deleted/typechanged submodules. 180 181-N:: 182--no-fetch:: 183 This option is only valid for the update command. 184 Don't fetch new objects from the remote site. 185 186--merge:: 187 This option is only valid for the update command. 188 Merge the commit recorded in the superproject into the current branch 189 of the submodule. If this option is given, the submodule's HEAD will 190 not be detached. If a merge failure prevents this process, you will 191 have to resolve the resulting conflicts within the submodule with the 192 usual conflict resolution tools. 193 If the key `submodule.$name.update` is set to `merge`, this option is 194 implicit. 195 196--rebase:: 197 This option is only valid for the update command. 198 Rebase the current branch onto the commit recorded in the 199 superproject. If this option is given, the submodule's HEAD will not 200 be detached. If a a merge failure prevents this process, you will have 201 to resolve these failures with linkgit:git-rebase[1]. 202 If the key `submodule.$name.update` is set to `rebase`, this option is 203 implicit. 204 205--reference <repository>:: 206 This option is only valid for add and update commands. These 207 commands sometimes need to clone a remote repository. In this case, 208 this option will be passed to the linkgit:git-clone[1] command. 209+ 210*NOTE*: Do *not* use this option unless you have read the note 211for linkgit:git-clone[1]'s --reference and --shared options carefully. 212 213<path>...:: 214 Paths to submodule(s). When specified this will restrict the command 215 to only operate on the submodules found at the specified paths. 216 (This argument is required with add). 217 218FILES 219----- 220When initializing submodules, a .gitmodules file in the top-level directory 221of the containing repository is used to find the url of each submodule. 222This file should be formatted in the same way as `$GIT_DIR/config`. The key 223to each submodule url is "submodule.$name.url". See linkgit:gitmodules[5] 224for details. 225 226 227AUTHOR 228------ 229Written by Lars Hjemli <hjemli@gmail.com> 230 231GIT 232--- 233Part of the linkgit:git[1] suite