Awk substr has built-in functions that can help us select substrings anywhere in the input string.
substr syntax
substr(s, m, n)
- s : input string
- m : start position
- n : length of substring
Examples
In the following awk example, we will use the awk substr built-in function to intercept the input string substring.
Test string:
awk:substr:substring
Output “substr” substring:
➜ ~ echo "awk:substr:substring" | awk '{print substr($0,5,6)}'
substr
Parameter explanation – substr($0,5,6)
- $0: input string
- 5: means starting from the fifth digit, including the fifth digit
- 6: Substring character length
ok.
In the above example, we showed how to use the awk substr built-in function to intercept substrings.
Of course, for the above regular string, we can use awk delimiter to separate the fields.
➜ ~ echo "awk:substr:substring" | awk -F":" '{print $2}'
substr
➜ ~ echo "awk:substr:substring" | awk 'BEGIN{FS=":"}{print $2}'
substr
Of course, this method can only handle regular strings. Irregular strings, we can only use the substr function.