string from $string at $position.
If the $string parameter is "*" or "@", then this extracts the positional... # Three characters of substring.
If the $string parameter is "*" or "@", then this extracts a maximum of $l... rror message. If no error message is given, print parameter null or not set. Note: In a non-interactive shell... o bar baz; do eval echo \${$foo:?} one bash: bar: parameter null or not set bash: baz: parameter null or not
