[collection] Simple usage of git

An Introduction to git
============================================================
good introduction: Randall Schwartz on git
life before git
git as as an prime example of software engineering under Unix
git objects are identified by SHA1 sums!

objects:
  blobs (file contents)
  trees (blobs or other trees)
  commits (tree, parent commits, message)
  tags (object (usally commit), name (2.6.26), message, signature)
  one SHA1 commit describes complete history (uniquely, cryptographically strong)
  Denx git trees and gitweb
  Stacked git

GUI tools:
  gitk
  git-gui

  tig

 

stages: working dir -> index (stage area) git-object db

simple git commands:

introduce yourself:
$ git config --global user.name "Your Name Comes Here"
$ git config --global user.email

 

clone a repository:
$ git-clone git://

 

look at the history
$ git-log

 

add a branch for hacking
$ git-checkout -b hacking HEAD

 

edit some files and look at changes in working dir
$ git diff

 

add modified files to the index:
$ git add file1 file2

 

delete some and mark them as deleted:
$ git rm file3

 

look at diffs of the modified files added to the index
$ git diff --cached

 

get some general statistics of which files were modified:
$ git status

 

to throw away the changes git reset HEAD, to reset the working directory git-checkout -f

commit the changes added to the index (will be prompted for commit message)
$ git commit

 

alternatively without using the index as an intermediate stage:
$ git commit -a

 

unhappy with commit message?
$ git commit --amend

local branches

what branches have we got?
$git branch

 

create a branch as a clone of the current branch:
$ git branch hacking

 

check out the contents of this branch:
git checkout hacking

 

hack around, make a mess of it and decide to throw it away
git checkout -f
git checkout master
git branch -d hacking

remote branches

add a new remote branch
$ git remote add vanilla git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git

 

fetch the objects but don't merge
$ git fetch vanilla

 

look at remote branches
$ git branch -r

 

merge one with main kernel branch
$ git-merge vanilla/master

 

goodies:
o whos fault is it: git-blame
o which commit introduced the bug: git-bisect
o maintain a clean repository: git-gc
o check repository for consistence: git-fsck

o remove all those untracked files: git-clean

 

tree too big?
o use a shared repository (objects on demand) git-clone -s
o git-clone --reference : reference a local repository
o make a shallow copy: git-clone --depth