Extract lines between 2 tokens in a text file using bash

Question

i have a text file which looks like this:

random useless text 
 
para1 
para2 
para3 
 
random us         


        

Answer 1

No need for head and tail or grep or to read the file multiple times:

sed -n '//{:a;n;//b;p;ba}' inputfile

Explanation:

• -n - don't do an implicit print
• //{ - if the starting marker is found, then
  • :a - label "a"
    • n - read the next line
    • //q - if it's the ending marker, quit
    • p - otherwise, print the line
  • ba - branch to label "a"
• } end if