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Git Commands

August 14, 2017 22:57

Git Commands: Step By Step Guide (Part 1)

In this tutorial, we will go through basic Git commands step by step and see how to use in the project. Also, we will put the code in the cloud using GitHub. It is assumed Git is already installed and configured on your machine. I am using Windows 10 for this post, but the same Git commands can be applied on Linux/Ubuntu.

1. To create a new local repository:

Let’s create a directory for repository.

mkdir repo
cd repo

use following command to create repository

git init

It creates a .git directory that contains all the Git-related information for your project.

2. Create new file file1.txt and file2.txt in repo directory and run following command to check status.

git status

Status command displays a list the files you’ve changed and those you still need to add or commit.

3. Adding files:

Run following command to add both files:

git add file1.txt file2.txt

Add command adds one or more files to staging (index).

4. Commit:

After staging files, we can commit them into Git. Run following command to commit:

git commit -m "First commit"

-m for commit message.

you can use -a to commit any files you’ve added with git add, and also commit any files you’ve changed since then.

git commit -a

Note: it is dangerous. let’s say you opened a file and changed it by mistake. if you add -a to your commit, all files would be committed and you would fail to notice possible errors.

You can use both -a and -m as well

git commit -am "My commit message"

5. Further Commits:

Let’s modify file1.txt after first commit. Now to check the changes from the last commit, run following command:

git diff

If you want to have a look at the changes to a particular file, you can run git diff <file>.
Let’s commit the changes

git commit -am "Second commit"

6. To show log:

To check the history of your project, run the following command:

git log

To view the details of a particular commit:

git show <hash>

Where <hash> is the hex number associated with the commit. you do not need to copy the whole string, and the first 5-6 characters are enough to identify your commit. As in the screenshot, only d9f8 is used.

7. To put code on remote server:

You could create a project on GitHub, GitLab, or BitBucket and push your existing code to the repository. Conveniently, a remote to which you have write access is called the origin.

Run following commands to add a remote origin and then push the code to the origin.

git remote add origin https://github.com/techbrij/gitsample.git
git push -u origin master

Push command is used to send changes to remote repository.

Git Commands: Step By Step Guide (Part 2)

1. Checkout a repository:

To create a working copy of a local repository by running the command

git clone /path/to/repository

when using a remote server, your command will be

git clone username@host:/path/to/repository

In our case, as it is public Github repo so simple link is used

2. Branching:

Let’s create a new branch “branch1” and switch on it

git checkout -b branch1

Modify file2.txt manually then check status and commit it.

git status
git commit -am "Branch1 first commit"

To push the branch to your remote repository, so others can use it:

git push -u origin branch1

To list all the branches in your repository and to know what branch you’re currently in, run following command:

git branch

To switch from one branch to another:

git checkout <branchname>

3. Merging:

Before merging, you can preview the changes using git diff command:

git diff master branch1

If everything looks okay then use following command to to merge branch1 into your active branch (e.g. master)

git merge branch1

4. Update your code:

To update your local repository to the newest commit from the remote repository, run following command:

git pull

5. Undo Local Changes:

If you want to sync local code with remote code and drop all your local changes and commits then run following command:

git fetch origin
git reset --hard origin/master

6. Reset Last commit only:

If you do wrong commit by mistake and want to remove all changes in last commit, run following command

git reset --hard HEAD~1

Conclusion:

In this tutorial, we have covered basic Git commands related to branching and merging.
Here is Oliver Steele’s image of how all it all fits together:

Hope, It helps. Enjoy Git !!

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