git and line endings, core.autocrlf

Ah line endings; \r\n vs \n

Some OSes, such as Windows, prefer carriage returns and new lines: (\r\n)

While others, such as Linux and Mac, prefer new lines: (\n)

This default preference is not a problem, until you start sharing code across OSes using a version control system, like git.

For example, if your Windows ide enters \r\n for new lines, or worse, on save converts all lines to \r\n, while another developer's Linux ide enters \n for new lines, and also on save converts all lines to \n, the version control system will mark all affected lines as changed, when really it was just line endings.

To minimize the unintentional changing of line endings:
1) Developers can agree on the desired line ending and adjust their ide to save as such.
The desired line ending often depends on whether the target OS for the code is Linux or Windows, matching the OS preference.
2) Git by default can help manage line endings on commits and checkouts, by setting the config flag:

core.autocrlf

config.autocrlf=true

If you’re programming on Windows and working with people who are not (or vice-versa), you’ll probably run into line-ending issues at some point. This is because Windows uses both a carriage-return character and a linefeed character for newlines in its files, whereas Mac and Linux systems use only the linefeed character. This is a subtle but incredibly annoying fact of cross-platform work; many editors on Windows silently replace existing LF-style line endings with CRLF, or insert both line-ending characters when the user hits the enter key.
Git can handle this by auto-converting CRLF line endings into LF when you add a file to the index, and vice versa when it checks out code onto your filesystem. You can turn on this functionality with the core.autocrlf setting. If you’re on a Windows machine, set it to true – this converts LF endings into CRLF when you check out code:

> git config --global core.autocrlf true

config.autocrlf=input

If you’re on a Linux or Mac system that uses LF line endings, then you don’t want Git to automatically convert them when you check out files; however, if a file with CRLF endings accidentally gets introduced, then you may want Git to fix it. You can tell Git to convert CRLF to LF on commit but not the other way around by setting core.autocrlf to input:

> git config --global core.autocrlf input

This setup should leave you with CRLF endings in Windows checkouts, but LF endings on Mac and Linux systems and in the repository.

config.autocrlf=false

If you’re a Windows programmer doing a Windows-only project, then you can turn off this functionality, recording the carriage returns in the repository by setting the config value to false:

> git config --global core.autocrlf false

Note: Above 2) sourced from Git Book

This is the recommended option if you want to manage line endings yourself; no magic = good

Note: You can also manually edit the git global config by editing the file in

> echo C:\Users\[username]\.gitconfig

[user]

name = first last

email = your@email.com

[core]

autocrlf = true

   

Further reading on StackOverflow

End of document.  Thanks for reading.