Git 101.

Basics:

• help / man 
• man git
• man git-log / man git-commit
• git help log

• git config --global user.name <your_name>
• git config --global user.email you@yourdomain.com
• git config --get remote.origin.ur /home/amy/project
• git config -l # 
• git init
• git status
• git log (more)
• git add <filename> (more)
• git commit -m "message" <filename> (more)
• git branch <branch_name> (more)
• git checkout master 
• git checkout -b <branch_name>
• git branch (check branch is created)
• git merge (more)
• git branch -d <branch-to-delete> # but git ensure the changes is in current branch
• git branch -D <branch-to-remove> # no changes are reserved
• git branch -r origin/master # keeps a pristine copy of original branch
• git revert (more)
• git clone <directory> <new cloned directory>
• git commit -a # to commit the new cloned directory in repository
• ex: git clone amy.org:/home/amy/project  my_repo_directory # ssh protocol
• git pull <new cloned directory>
• git fetch <new cloned directory> # to inspect new changes and decide whether to merge
• git log -p HEAD..FETCH_HEAD
• gitk HEAD..FETCH_HEAD
• gitk HEAD...FETCH_HEAD  # show everything reachable from either one but not both
• git remote add <new directory> <from directory>
• git fetch <new directory> # inspect without merging
• git log -p master..new_directory/master # show a list of changes
• git merge new_directory/master
• git pull . remotes/new_directory/master # same as above commands, merge without checking
• git pull # update all changes to local files
• git push # update files in remote github repository

• git show <commit number>
• git show HEAD # tip of current branch
• git show HEAD^    # parent
• git show HEAD^^  # grandparent
• git show experiment1 # tip of experiment1 branch

• more...
• git rm [-n][-q][-r] <dir to be removed>
• git tag v2.5 <your own commit name.
• git diff v2.5 HEAD
• git branch new_branch v2.5
• git reset --hard HEAD^
• git grep "key_word" v2.5
• git log v2.5..v2.7
• git log --since="2 days ago"
• git log v2.5..  Makefile
• git log master .. child # commit in child but not master
• gitk --since="2 days ago"  codec/
• git diff  v2.5:Makefile  HEAD:Makefile.in
• git show v2.5:Makefile
• git docs
• git tutorial files

EXAMPLE

% tar xzf project.tar.gz
% cd project
% git init
% git add .
% git commit
% git add file1 file2
% git diff --cached
% git status
% git commit -a -m "new changes"
% git log -p
% git log --stat --summary
% git branch experiment1
% git branch
% git checkout experiment1
    ... (edit files)
% git commit -a
% git checkout master
    ... (edit files)
% git commit -a
% git merge experiment1
% git diff
% git commit -a
% (git push to update files in remote github repository)
% git branch -d experiment1
% git branch -D crazy-idea-to-remove

GitHub:

• git remote add origin https://github.com/myaccount/mynewrepository.git
• git push -u origin master_branch_name
• git hash object - use hash code as an identifier for a specific commit
• git revert <has code number> - to backtrack
• git pull origin master_branch_name - get most recent changes to local computer