If you don't mind always including .sh on the script file name, then you can keep the same script for Cygwin and Unix (Macbook).
To illustrate:
1. Always include .sh to your script file name, e.g., test1.sh
2. test1.sh looks like the following as an example:
3. On Windows with Cygwin, you type "test1.sh" to run#!/bin/bash
echo '$0 = ' $0
echo '$1 = ' $1
filepath=$1
4. On a Unix, you also type "test1.sh" to run
Note: On Windows, you need to use the file explorer to do following once:
1. Open the file explorer
2. Right-click on a file with .sh extension, like test1.sh
3. Open with... -> Select sh.exe
After this, your Windows 10 remembers to execute all .sh files with sh.exe.
Note: Using this method, you do not need to prepend your script file name with bash to run