Short introduction

Sometimes people need to specify multiple values for single .gitconfig file or they want to share just part of the configuration between two machines. There are different approaches for that. I can show you mine.

Different configs for different Operating Systems

On my private computer, I use Linux. I use Git for my private projects and I use my private e-mail address there. At the same time, I use Git at work on macOS with exactly the same Git configuration, but with a different e-mail address. How to deal with that? In my .gitconfig file, I set my private e-mail address, which is used by default. In my .zshrc file, I created two aliases:

alias setupGitPersonal="git config --global user.email \"piotr@wittchen.biz.pl\""
alias setupGitForWork="git config --global user.email \"piotr.wittchen@sap.com\""

Hint: If you want to configure more stuff than just an e-mail, you can do it in the appropriate alias or you can create separate shell scripts for that and place them in /usr/local/bin/ directory. Then, on Linux, I don’t have to do anything and my private e-mail address is used out-of-the-box. On macOS, I do the following trick in .zshrc file:

if [ `uname` = "Darwin" ]; then
  setupGitForWork

  # rest of the macOS config goes here...
fi

After that, every time I start terminal on macOS, it automatically sets up my e-mail address to the one I use at work and keeps my .gitconfig file updated. Hint: If you don’t use zsh, instead of .zshrc file, edit .bashrc file.

Different configs for the same OS on two machines

If you’re using different configs on the different machines with the same OS, you can try another trick. Create configuration file - e.g. .machine_name in your home directory. Setup one name on one machine and another name on a different machine. Next, include this file in your .zshrc or .bashrc file, perform appropriate check and load different settings basing on variable name.

. ~/.machine_name

if [ $machineName = "workMachine" ]; then
  setupGitForWork
else
  setupGitPersonal
fi

Contents of the .machine_name file are simple:

machineName="workMachine"

Different configs on the single machine with one OS

In such case, we are supposed to perform the manual switch. We can use aliases provided above. When we want to have personal settings, we can open terminal and type setupGitPersonal. When we want to apply work settings, then we can type setupGitForWork.

Summary

As we can see, keeping different configs for different machines or operating systems and changing them depending on our needs is not so hard. I hope these ideas will help you to manage your configs.