Question

In a sh shell script.

Given data in a text file:

string1  
string2 gibberish  
gibberish  
string3 gibberish  
string4  

How could you use awk or sed to remove all lines between string2 (inclusive) and string3 (not including string3)?

to end up with:

string1  
string3  
string4  

Answer 1

you can try this. Anything before “string2” will not be deleted.

awk 'BEGIN{f=0}
{
    match($0,"string2")
    if(RSTART){
        print substr($0,1,RSTART-1)
        f=1
        next
    }
    match($0,"string3")
    if(RSTART){
        $0=substr($0,RSTART)
        f=0
    }
}
f==0{print}
' file

output

$ cat file
string1 blah blah
text before string2 junk
gibberish
gibberis string3 text here
string4

$ ./shell.sh
string1 blah blah
text before
string3 text here
string4