Looping Through Subdirectories and Running a Command in Each

Question

I have a set of repositories sorted into directories based on their VCS (Git, Mercurial, SVN). With Subversion I was able to run svn update * in the parent directory and it would loop through each directory and update each repository as expected. That's not the case for Git or Mercurial.

I would like to come up with a bash script that I can run to do exactly that, loop through directories and either git pull or hg pull in each. I just don't have much bash scripting experience.

Answer 1

for dir in ~/projects/git/*
do
  (cd $dir && git pull)
done

Answer 2

If you have GNU Parallel http:// www.gnu.org/software/parallel/ installed you can do this:

cd ~/projects/git/; ls | parallel 'cd {} && git pull'

This will run in parallel so if some of the git servers' network connection are slow this may speed up things.

Watch the intro video for GNU Parallel to learn more: http://www.youtube.com/watch?v=OpaiGYxkSuQ

Answer 3

If you need it to be recursive:

find . -type d -name .git -exec sh -c "cd \"{}\"/../ && pwd && git pull" \;

This will descend into all the directories under the current one, and perform a git pull on those subdirectories that have a .git directory (you can limit it with -maxdepth).