SHELL

substring in shell script

STR="birthday-091216-pics"
SUBSTR=$(echo $STR | cut -d'-' -f 2)
echo $SUBSTR

substring in string shell

# You can do it in two ways
# 1) Let "grep" read on its standard input

echo "$line" | grep -o select

# 2) tell "grep" here is the string

grep select <<< "$line"