Installation

For Linux, the required packages are « git-core » (the real package) and « gitk » (graphical interface).

sudo apt-get install git-core gitk

For Mac Os X, you can use the installer from here.

Configuration

Activate the color in Git : your messages will be more readable.

git config --global color.diff auto
git config --global color.status auto
git config --global color.branch auto

Now, you have to configure your name and your email

git config --global user.name "your_pseudo"
git config --global user.email my_email@domain.com

All these informations are in the ~/.gitconfig file. You can add some aliases at the end. The aliases allow you to put a shortcut for git commands.

[color]
        diff = auto
        status = auto
        branch = auto
[user]
        name = votre_pseudo
        email = moi@email.com
[alias]
        ci = commit
        co = checkout
        st = status
        br = branch

Getting started

• Create a new rep

Create a new directory (for example : /home/jerome/workspace/my_project/). With your console, go in your directory and type

git init

This will create an hidden directory .git

• Clone an existing rep

In this case, we are gonna clone a repository from GitHub (for example : http://github.com/symfony/symfony.git).

git clone http://github.com/symfony/symfony.git

Methodology

1. Modify the source code
2. test if your app is still working
3. make a commit to save the changes and let know Git
4. restart to step 1

The following command line will give you the modified files of your project.

git status

To see the differences, type

git diff src/Symfony/Components/Yaml/Yaml.php

Make a commit
You must specify the file you want to commit. Making a git status will mark your modified files in red. They will not be taken into account during the commit.

1. git add file1 file2 : this add the files for the « to commit » list. Then you have to make a git commit. Used when you create new files Git doesn’t know.
2. git comment -a will commit all the files (Changes to be committed and Changed but not updated). Used to save all the changes you’ve made.
3. git commit file1 file2 indicate the files and commit them. Used to commit specific files.

When a commit is done, vim or nano open. You have to write a message describing your changes.

All these commit are local. Except if you send the commit to the server (we will see that later). For the moment, you can cancel your last commit.