How to use gitignore command in git

I'm working first time on git. I have pushed my branch on github and it pushed all the library and documents into the github. Now what can I do and how can I use gitignore command to avoid the same mistake again.

Solution 1:

So based on what you said, these files are libraries/documentation you don't want to delete but also don't want to push to github. Let say you have your project in folder your_project and a doc directory: your_project/doc.

1. Remove it from the project directory (without actually deleting it): git rm --cached doc/*
2. If you don't already have a .gitignore, you can make one right inside of your project folder: project/.gitignore.
3. Put doc/* in the .gitignore
4. Stage the file to commit: git add project/.gitignore
5. Commit: git commit -m "message".
6. Push your change to github.

Solution 2:

If you dont have a .gitignore file, first use:

touch .gitignore

then this command to add lines in your gitignore file:

echo 'application/cache' >> .gitignore

Be careful about new lines

Solution 3:

git ignore is a convention in git. Setting a file by the name of .gitignore will ignore the files in that directory and deeper directories that match the patterns that the file contains. The most common use is just to have one file like this at the top level. But you can add others deeper in your directory structure to ignore even more patterns or stop ignoring them for that directory and subsequently deeper ones.

Likewise, you can "unignore" certain files in a deeper structure or a specific subset (ie, you ignore *.log but want to still track important.log) by specifying patterns beginning with !. eg:

*.log !important.log

will ignore all log files but will track files named important.log

If you are tracking files you meant to ignore, delete them, add the pattern to you .gitignore file and add all the changes

# delete files that should be ignored, or untrack them with 
# git rm --cached <file list or pattern>

# stage all the changes git commit
git add -A 

from now on your repository will not have them tracked.

If you would like to clean up your history, you can

# if you want to correct the last 10 commits
git rebase -i --preserve-merges HEAD~10 

then mark each commit with e or edit. Save the plan. Now git will replay your history stopping at each commit you marked with e. Here you delete the files you don't want, git add -A and then git rebase --continue until you are done. Your history will be clean. Make sure you tell you coworkers as you will have to force push and they will have to rebase what they didn't push yet.

Solution 4:

There is a file in your git root directory named .gitignore. It's a file, not a command. You just need to insert the names of the files that you want to ignore, and they will automatically be ignored. For example, if you wanted to ignore all emacs autosave files, which end in ~, then you could add this line:

*~

If you want to remove the unwanted files from your branch, you can use git add -A, which "removes files that are no longer in the working tree".

Note: What I called the "git root directory" is simply the directory in which you used git init for the first time. It is also where you can find the .git directory.