Nature of the Command field:
- Shell: execute the Command contents with /bin/sh on Unix (can be overridden with Shell executable on Configure System page), and cmd.exe on Windows,
- XShell: convert the Command contents to match the environment variable and separator syntax on the platform (for instance $HOME/foo becomes %HOME%\foo on Windows and vice-versa), add the workspace in the PATH to avoid the ./foo syntax to execute a script in the current folder, then execute the result with /bin/sh on Unix (can be overridden with Shell executable on Configure System page), and cmd.exe on Windows,
- Python: execute the Command contents with the Python executable.