a=12345678
echo ${a:-4}
</code>
intending to print the last four characters of $a. The problem is t... return its value. If it doesn't exist or is null, print the error message. If no error message is given, print parameter null or not set. Note: In a non-interac... t script. In an interactive shell, this will just print the error message. export foo="one" for i in foo
