Detecting Your Bash Environment: Linux, macOS, WSL, or Git Bash?

When writing cross-platform shell scripts, one of the first headaches you’ll run into is:
“Where am I running this code?”

• Is it a native Linux box?
• A macOS machine with Apple’s ancient Bash?
• A Windows developer using Git Bash?
• Or maybe WSL1/WSL2?

Having a simple way to detect the environment can save you from subtle bugs and let you adapt your scripts automatically.

A Minimal Bash Function

Here’s a tiny function I wrote that prints the operating system and the Bash version in a clean one-liner:

#!/bin/bash

detect_environment() {
    local kernel env bash_version
    kernel="$(uname -s)"
    bash_version="${BASH_VERSION%%(*}"

    case "$kernel" in
        Linux)
            if grep -qi "microsoft" /proc/version 2>/dev/null; then
                if uname -r | grep -qi "microsoft-standard"; then
                    env="WSL2"
                else
                    env="WSL1"
                fi
            else
                env="Linux"
            fi
            ;;
        Darwin)
            env="macOS"
            ;;
        MINGW*|MSYS*|CYGWIN*)
            env="Git Bash"
            ;;
        *)
            env="Unknown"
            ;;
    esac

    echo "$env;bash $bash_version"
}

detect_environment

Example Outputs

Depending on where you run it, you might see:

Linux;bash 5.2.32
macOS;bash 3.2.57
Git Bash;bash 5.2.15
WSL1;bash 5.1.16
WSL2;bash 5.1.16

Notice how it distinguishes between WSL1 vs WSL2 (they have different kernel signatures) and reports the Bash version in a short format.

Why This Matters

If you build scripts that should run everywhere, you often need to tweak behavior:

• Linux vs macOS → package managers (apt vs brew)
• Git Bash → Windows path quirks
• WSL1 vs WSL2 → networking and filesystem differences

By detecting the environment first, you can conditionally branch your script without breaking things.

Project & Source

The function lives in a small GitHub repo:
👉 kpatronas/whatos

Feel free to fork it, improve it, or drop it into your ~/.bashrc.

✍️ That’s it — a simple, practical snippet that makes cross-platform scripting easier!