...

• Changes in working copy vs. previous commit:

  Code Block
  git diff <commit>

• Changes between two previous commits:

  Code Block
  git diff <commit1> <commit2>

Working With Remote Repositories

...

$ git pull origin master

Pushing changes

Use git push to send your committed changes to a remote repository:

...

To fix this, you need to pull from that repo, merge changes, and then push.

Sharing your repository

If you will be sharing a repository with others (or with yourself on multiple computers), you will need to create a "bare" repository – that is, a repository without a working copy. You do this with the -b flag to git init:

...

You can then clone this repository, pull from it, and push to it as described in the previous section.

Conflicts

A conflict occurrs when two people make overlapping changes.

...

• add the files with git add
• commit the changes with git commit.

Log, Tags, and Branches

Viewing history

The git log command shows you the history of your repository:

...

$ git log
commit 7c8c3e71893d7481fdd9c13ec8f53cb9c61fac50
Author: testuser lastname  <testuser@g.harvard.edu>
Date:   Tue Sep 18 12:46:46 2018 -0400

    changed GNU to Microsoft

commit 257f2f3ff44c2165c1182d3673a825fcadf121aa
Author: testuser lastname  <testuser@g.harvard.edu>
Date:   Tue Sep 18 12:46:46 2018 -0400

    made a change

commit 99c4fb8f37e48284d79c7396aaf755b514d6a249
Author: testuser lastname  <testuser@g.harvard.edu>
Date:   Tue Sep 18 12:46:45 2018 -0400

    made some changes

commit 20cc63576f7c88541f5b9471e20f4d1c5f8afcb9
Author: testuser lastname  <testuser@g.harvard.edu>
Date:   Tue Sep 18 12:46:45 2018 -0400

    initial import

Tagging and branching

Git has explicit support for tagging and branching.

• git tag manipulates tags
• git branch and git checkout manipulate branches

Tags

Create a tag:

$ git tag [-a] TAGNAME

...

To list available tags:

$ git tag

Branches

List branches:

$ git branch

...

$ git checkout master
$ git merge dev
Updating 1288ed3..33e4a4c
Fast-forward
 version-control.rst |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

The Git Index

...

• The index is a staging area between your working copy and your local repository.
• git add adds files to the index
• git commit commits files from the index to the repository.

...

• git diff is the difference between your working copy and the index.
• git diff HEAD is the difference between your working copy and the local repository.
• git diff --cached is the difference between the index and the local repository.

Refer back to this illustration if you get confused: