This expression:FN=27LN=145cat $FILENAME | sed -n $FN,$LNpis failing with this error: sed: -e expression #1, char 3: unexpected `,'but when I used actual numbers, I get the expected results. There are no special characters embedded, nor are there trailing or leading spacescat $FILENAME | sed -n 27,145pWhat is going on here?
sed won't recognize numbers when passed as variables
sed;variable