Git for beginners: The definitive practical guide

Answer 1

How do you 'tag' a particular set of revisions

How do you 'mark' 'tag' or 'release' a particular set of revisions for a particular set of files so you can always pull that one later?

Using the git tag command.

To simply "tag" the current revision, you would just run..

git tag -a thetagname
git tag -a 0.1
git tag -a 2.6.1-rc1 -m 'Released on 01/02/03'

To list the current tags, simply run git tag with no arguments, or -l (lower case L):

$ git tag -a thetagname # and enter a message, or use -m 'My tag annotation'
$ git tag -l
thetagname

To delete a tag, you use the -d flag:

$ git tag -d thetagname 
Deleted tag 'thetagname'
$ git tag
[no output]

To tag a specific (previous) commit, you simply do..

git tag [tag name] [revision SHA1 hash]

For example:

git tag 1.1.1 81b15a68c6c3e71f72e766931df4e6499990385b

---

Note: by default, git creates a "lightweight" tag (basically a reference to a specific revision). The "right" way is to use the -a flag. This will launch your editor asking for a tag message (identical to asking for a commit message, you can also use the -m flag to supply the tag message on the command line). Using an annotated tag creates an object with its own ID, date, tagger (author), and optionally a GPG signature (using the -s tag). For further information on this, see this post

git tag mytagwithmsg -a -m 'This is a tag, with message'

And to list the tags with annotations, use the -n1 flag to show 1 line of each tag message (-n245 to show the first 245 lines of each annotation, and so on):

$ git tag -l -n1
mytagwithmsg    This is a tag, with message

For more information, see the git-tag(1) Manual Page

Answer 2

Git Magic is all you'll ever need. Guaranteed or your money back!

Answer 3

How to install Git

On Windows:

Install msysgit

There are several downloads:

• Git: Use this unless you specifically need one of the other options below.
• PortableGit: Use this if you want to run Git on a PC without installing on that PC (e.g. running Git from a USB drive)
• msysGit: Use this if you want to develop Git itself. If you just want to use Git for your source code, but don't want to edit Git's source code, you don't need this.

This also installs a Cygwin bash shell, so you can use the git in a nicer shell (than cmd.exe), and also includes git-gui (accessible via git gui command, or the Start > All Programs > Git menu)

Mac OS X

Use the git-osx-installer, or you can also install from source

Via a package manager

Install git using your native package manager. For example, on Debian (or Ubuntu):

apt-get install git-core

Or on Mac OS X, via MacPorts:

sudo port install git-core+bash_completion+doc

…or fink:

fink install git

…or Homebrew:

brew install git

On Red Hat based distributions, such as Fedora:

yum install git

In Cygwin the Git package can be found under the "devel" section

From source (Mac OS X/Linux/BSD/etc.)

In Mac OS X, if you have the Developer Tools installed, you can compile Git from source very easily. Download the latest version of Git as a .tar.bz or .tar.gz from http://git-scm.com/, and extract it (double click in Finder)

On Linux/BSD/etc. it should be much the same. For example, in Debian (and Ubuntu), you need to install the build-essential package via apt.

Then in a Terminal, cd to where you extracted the files (Running cd ~/Downloads/git*/ should work), and then run..

./configure && make && sudo make install

This will install Git into the default place (/usr/local - so git will be in /usr/local/bin/git)

It will prompt you to enter your password (for sudo), this is so it can write to the /usr/local/ directory, which can only be accessed by the "root" user so sudo is required!

If you with to install it somewhere separate (so Git's files aren't mixed in with other tools), use --prefix with the configure command:

./configure --prefix=/usr/local/gitpath
make
sudo make install

This will install the git binary into /usr/local/bin/gitpath/bin/git - so you don't have to type that every time you, you should add into your $PATH by adding the following line into your ~/.profile:

export PATH="${PATH}:/usr/local/bin/gitpath/bin/"

If you do not have sudo access, you can use --prefix=/Users/myusername/bin and install into your home directory. Remember to add ~/bin/ to $PATH

The script x-git-update-to-latest-version automates a lot of this:

This script updates my local clone of the git repo (localy at ~/work/track/git), and then configures, installs (at /usr/local/git-git describe) and updates the /usr/local/git symlink.

This way, I can have /usr/local/git/bin in my PATH and I'm always using the latest version.

The latest version of this script also installs the man pages. You need to tweak your MANPATH to include the /usr/local/git/share/man directory.

Answer 4

Commit Changes

Once you've edited a file, you need to commit your changes to git. When you execute this command it will ask for a commit message - which is just a simple bit of text that tells everyone what you've changed.

$ git commit source/main.c

Will commit the file main.c in the directory ./source/

$ git commit -a # the -a flag pulls in all modified files

will commit all changed files (but not new files, those need to be added to the index with git-add). If you want to commit only certain files then you will need to stage them first with git-add and then commit without the -a flag.

Commiting only changes your local repository though not the remote repositories. If you want to send the commits to the remote repository then you will need to do a push.

$ git push <remote> <branch> # push new commits to the <branch> on the <remote> repository

For someone coming from CVS or SVN this is a change since the commit to the central repository now requires two steps.

Answer 5

How do I delete a branch on a remote repository?

Perform a push in your remote using : before the name of the branch

git push origin :mybranchname

being origin the name of your remote and mybranchname the name of the branch about to be deleted

http://help.github.com/remotes/

Answer 6

Checking Out Code

First go to an empty dir, use "git init" to make it a repository, then clone the remote repo into your own.

git clone user@host.com:/dir/to/repo

Wherever you initially clone from is where "git pull" will pull from by default.