You've installed git, and you want to create a repository. You can do this in an empty directory, but probably you already have a project you think should be under version control. cd into the project directory, and type
git init. This isn't dangerous: it makes the folder a git repo ... with no committed files, and without changing any of the contents of the folder. Mechanically, all it does is add a .git/ folder to the project folder (there's a bunch of stuff in there, but it's best to ignore the man behind the curtain).
Before you go any further, let's do one basic bit of configuration. By default on Linux systems, the git editor is nano - and I'm not having that. So let's change that:
git config --global core-editor "vim" will change git's default editor to something better.
Now start adding files to the repo. You don't have to add all of them: use
git add <filename> <foldername> <...> to "stage" stuff. To "stage a file" (or everything in a folder) means that you consider it ready to be added to the repository: you haven't actually put it into the repo yet. Then
git commit -a will get you into the git editor, which will show you what you're committing (and what you're not committing) and ask you to add a commit message. If you modify the file and save it, a commit will be made - but you can cancel the commit by exiting the editor without saving anything.
git status is always your friend. Use it. Frequently. This will tell you what's changed and what's staged. And commit early and often: making lots of commits is NOT a problem, and may save you later.
Git is an incredibly complex source code management system - it was designed for thousands of developers to work on the Linux kernel, including multiple simultaneous branches. Honestly, I'm only scratching the surface of what it can do. If you're new to it, work with this first: work on your project and commit frequently. Get to branching and servers when you need it, no rush.
But ... I need a server, so that's the next step in this little tutorial. This is actually pretty easy, although what's happening may not be terribly clear. I have the server set up, so I'm not covering that here - just how to get a new project onto an existing server. Go to the parent directory of your git-controlled project, and type
git clone --bare projectX projectX.git . This will create a new folder called projectX.git/, a "bare" copy of the repo meant for a server (not for you to work in: things are stored differently). Next, run
scp -r projectX.git firstname.lastname@example.org:/home/gituser. And you're done. After that, on any other machine,
git clone email@example.com:/home/gituser/projectX.git new_folder ("new_folder" is optional, by default it will create "projectX" - notice without the ".git"). I would recommend removing the local copy:
rm -rf projectX.git ("-f" is needed as many of the items in .git/ are read-only). The repo you just cloned from doesn't know you've added an upstream, so you have to tell it: cd into the repo and run
git remote add origin firstname.lastname@example.org/home/gituser/projectX.git . And in projectX/ you can now type
git push origin master.
I highly recommend Pro Git v2: it's detailed, well structured, and readable and is about as good as technical documentation comes ... plus it's free and online. If you need a server, read Git on the Server.
2017-05-06: I've found myself using this entry a lot to create repos. So I'm going to add this in a stripped form, but with a bit more detail ... (and excessively colourful HTML).
~$ cd interestingproject interestingproject$ ls README.txt code.py morecode/ interestingproject$ git init Initialized empty Git repository in /home/giles/interestingproject/.git/ interestingproject$ git status On branch master Initial commit Untracked files: (use "git add
..." to include in what will be committed) README.txt code.py morecode/ nothing added to commit but untracked files present (use "git add" to track) interestingproject$ git add README.txt code.py morecode/** interestingproject$ git status On branch master Initial commit Changes to be committed: (use "git rm --cached ..." to unstage) new file: KeyboardMessagePullup/KeyboardMessagePullup.ino new file: KeyboardMessagePullupWithBlink/KeyboardMessagePullupWithBlink.ino new file: README.txt new file: StretchBlink/StretchBlink.ino new file: UglyBlink/UglyBlink.ino new file: libraries/readme.txt interestingproject$ git commit [master (root-commit) 977a07f] Initial commit of Interesting Project(TM). 6 files changed, 229 insertions(+) create mode 100644 README.txt create mode 100644 code.py create mode 100644 morecode/README.txt create mode 100644 morecode/backup.py interestingproject(master)$ cd .. ~$ git clone --bare interestingproject interestingproject.git Cloning into bare repository 'interestingproject.git'... done. ~$ scp -r interestingproject.git email@example.com:~/ config 100% 137 16.1KB/s 00:00 exclude 100% 240 10.8KB/s 00:00 pre-push.sample 100% 1348 105.3KB/s 00:00 pre-rebase.sample 100% 4951 268.3KB/s 00:00 update.sample 100% 3610 330.2KB/s 00:00 pre-applypatch.sample 100% 424 43.8KB/s 00:00 commit-msg.sample 100% 896 69.3KB/s 00:00 post-update.sample 100% 189 17.5KB/s 00:00 prepare-commit-msg.sample 100% 1239 70.6KB/s 00:00 applypatch-msg.sample 100% 478 46.9KB/s 00:00 pre-commit.sample 100% 1642 153.0KB/s 00:00 d5024a125e81002454258282b0a80ce18e3bf8 100% 58 6.5KB/s 00:00 ebcc21c9e9c1bad4c769968569b85f383f3064 100% 359 33.1KB/s 00:00 2011668008a8d81c181c90048ad7a0d2edad92 100% 79 7.9KB/s 00:00 dd11653f8f363e663119a01795de31a8f7ff90 100% 70 7.0KB/s 00:00 64bcbdb209f092b6a5c21f5165fa7d079ae7d1 100% 1068 106.5KB/s 00:00 201cebb4de048a019f0f6a267875fe33d28622 100% 61 5.3KB/s 00:00 f2cdb97709d840239de8ff6737d1367b85d40f 100% 464 54.3KB/s 00:00 7a07fb1a41c00cbdbd6155ed4ae7a2c0a9052d 100% 144 16.0KB/s 00:00 7bcf6e8c58be9f4208b976af1666746984f33e 100% 55 4.7KB/s 00:00 ce674fe0cc3be65c6d8872a3b109caaad73f07 100% 92 10.2KB/s 00:00 b83e825e795820ff65e1798619bb9e0792b843 100% 951 61.8KB/s 00:00 cdf5bc81ae6c3866e28d988fefe002148a0dd2 100% 229 27.2KB/s 00:00 HEAD 100% 23 2.6KB/s 00:00 packed-refs 100% 98 11.1KB/s 00:00 description 100% 73 8.5KB/s 00:00 ~$ rm -rf interestingproject.git/ ~$ cd interestingproject/ interestingproject(master)$ git remote add origin firstname.lastname@example.org:~/interestingproject.git # TYPO!!! interestingproject(master)$ git pull ssh: Could not resolve hostname myserv.com:~: Name or service not known fatal: Could not read from remote repository. Please make sure you have the correct access rights and the repository exists. interestingproject(master)$ git remote -v origin email@example.com:~/interestingproject.git (fetch) origin firstname.lastname@example.org:~/interestingproject.git (push) interestingproject(master)$ git remote add origin email@example.com:~/interestingproject.git fatal: remote origin already exists. interestingproject(master)$ git remote set-url origin firstname.lastname@example.org:~/interestingproject.git interestingproject(master)$ git push fatal: The current branch master has no upstream branch. To push the current branch and set the remote as upstream, use git push --set-upstream origin master interestingproject(master)$ git push --set-upstream origin master Branch master set up to track remote branch master from origin. Everything up-to-date interestingproject(master)$