SC2148

Include a shebang (#!) to specify the shell.

Problematic code:

echo "Hello World"

Correct code:

#!/bin/sh
echo "Hello World"

Rationale:

ShellCheck noticed that your file does not start with a shebang. Shebangs are good for a number of reasons:

• They allow scripts to be executed outside of interactive prompts.
• They ensure the script is executed by the correct shell.
• Editors and utilities (including shellcheck) use it to determine the file type.

Contraindications

For checking snippets, use shellcheck -e 2148. This is the default for shellcheck.net.