Easy way to pull latest of all git submodules

We're using git submodules to manage a couple of large projects that have dependencies on many other libraries we've developed. Each library is a separate repo brought into the dependent project as a submodule. During development, we often want to just go grab the latest version of every dependent submodule.

Does git have a built in command to do this? If not, how about a Windows batch file or similar that can do it?

If it's the first time you check-out a repo you need to use --init first:

git submodule update --init --recursive

For git 1.8.2 or above, the option --remote was added to support updating to latest tips of remote branches:

git submodule update --recursive --remote

This has the added benefit of respecting any "non default" branches specified in the .gitmodules or .git/config files (if you happen to have any, default is origin/master, in which case some of the other answers here would work as well).

For git 1.7.3 or above you can use (but the below gotchas around what update does still apply):

git submodule update --recursive

or:

git pull --recurse-submodules

if you want to pull your submodules to latest commits instead of the current commit the repo points to.

See git-submodule(1) for details

git pull --recurse-submodules --jobs=10

a feature git first learned in 1.8.5.

Until the bug is fixed, for the first time you do need to run

git submodule update --init --recursive

On init running the following command:

git submodule update --init --recursive

from within the git repo directory, works best for me.

This will pull all latest including submodules.

Explained

git - the base command to perform any git command
    submodule - Inspects, updates and manages submodules.
        update - Update the registered submodules to match what the superproject
        expects by cloning missing submodules and updating the working tree of the
        submodules. The "updating" can be done in several ways depending on command
        line options and the value of submodule.<name>.update configuration variable.
            --init without the explicit init step if you do not intend to customize
            any submodule locations.
            --recursive is specified, this command will recurse into the registered
            submodules, and update any nested submodules within.

After this you can just run:

git submodule update --recursive

from within the git repo directory, works best for me.

This will pull all latest including submodules.

Note: This is from 2009 and may have been good then but there are better options now.

We use this. It's called git-pup:

#!/bin/bash
# Exists to fully update the git repo that you are sitting in...

git pull && git submodule init && git submodule update && git submodule status

Just put it in a suitable bin directory (/usr/local/bin). If on Windows, you may need to modify the syntax to get it to work :)

Update:

In response to the comment by the original author about pulling in all of the HEADs of all of the submodules -- that is a good question.

I am pretty sure that git does not have a command for this internally. In order to do so, you would need to identify what HEAD really is for a submodule. That could be as simple as saying master is the most up to date branch, etc...

Following this, create a simple script that does the following:

1. check git submodule status for "modified" repositories. The first character of the output lines indicates this. If a sub-repo is modified, you may NOT want to proceed.
2. for each repo listed, cd into it's directory and run git checkout master && git pull. Check for errors.
3. At the end, I suggest you print a display to the user to indicate the current status of the submodules -- perhaps prompt them to add all and commit?

I'd like to mention that this style is not really what git submodules were designed for. Typically, you want to say "LibraryX" is at version "2.32" and will stay that way until I tell it to "upgrade".

That is, in a sense, what you are doing with the described script, but just more automatically. Care is required!

Update 2:

If you are on a windows platform, you may want to look at using Python to implement the script as it is very capable in these areas. If you are on unix/linux, then I suggest just a bash script.

Need any clarifications? Just post a comment.