Ksh command equivalent to islower() function

Question

I want to know if there's any command in ksh which is equivalent to islower() function of C?

Answer 1

Kind of: you can match against the pattern [[:lower:]]

islower() {
    [[ $1 == [[:lower:]] ]]
}

char=A
islower $char && echo $char is lower case || echo not lower case

char=a
islower $char && echo $char is lower case || echo not lower case