Chapter 15: Cross-Platform Strategies

Modern development rarely happens in a vacuum. You might develop on Windows but deploy to Linux, or use a Mac while managing Windows servers. This chapter covers the tools and strategies for writing scripts that bridge these ecosystems.

I. WSL: The Linux Engine on Windows

WSL (Windows Subsystem for Linux) has evolved from a translation layer (WSL1) to a full lightweight virtual machine running a genuine Linux kernel (WSL2).

WSL1 vs. WSL2

Feature	WSL1	WSL2
Linux Kernel	Emulated (Syscall Translation)	Genuine Linux Kernel
File System Perf	Fast (on Windows drive)	Ultra-Fast (on Linux drive)
Compatibility	Partial	Full (Docker, FUSE, etc.)
Architecture	Direct on Windows	Managed Hypervisor

II. The Power of Interop

One of the most unique features of WSL is the ability to mix Windows and Linux commands in a single pipeline.

1. Running Windows Tools from Linux

You can call .exe files from within Bash. WSL handles the path translation and execution.

# Search for text in a Windows directory using Linux grep
ls /mnt/c/Users/Jane/Documents | grep "Project"

# Open the current Linux directory in Windows Explorer
explorer.exe .

2. Running Linux Tools from CMD/PowerShell

# Get the first 5 lines of a file using Linux head from PowerShell
wsl head -n 5 data.txt

III. Path Translation: `wslpath`

Windows and Linux use different path formats.

Windows: C:\Users\Jane
Linux: /mnt/c/Users/Jane

The wslpath tool is essential for scripts that need to pass file paths between the two environments.

# Convert Windows path to Linux path
LINUX_PATH=$(wslpath "C:\Users\Jane\config.ini")

IV. Handling Cross-Platform Line Endings

As discussed in the previous chapter, CRLF vs LF is the most common cause of script failure.

Pro-Tip: Configure Git to handle this automatically by setting core.autocrlf to input (for Linux/Mac) or true (for Windows).
Manual Fix: Use the dos2unix tool to convert files.
- dos2unix my_script.sh

V. Universal Logic: The "If-Os" Pattern

If you are writing a script that must run on both Mac and Linux, you can detect the OS and adjust flags accordingly (e.g., sed flags are different on macOS).

OS_TYPE=$(uname)

if [[ "$OS_TYPE" == "Darwin" ]]; then
    # macOS Specific Logic
    sed -i '' 's/old/new/g' file.txt
elif [[ "$OS_TYPE" == "Linux" ]]; then
    # Linux Specific Logic
    sed -i 's/old/new/g' file.txt
fi

In the final chapter, we'll wrap up with Security and Best Practices to ensure your production scripts are safe and maintainable.

Cross-Platform Strategies