Shell Programming and Scripting

# cat infile
# Start
# List  (first header)
test 1
Lab 2
test 3
...
# Trials (second header)
round 1
run 5
...
# Users
John
Sally
Denise
# End

# ./justdoit infile
input your value..= List
Dou you want to save results to a file [y/n]? n
 
**********  Results  **********
test 1
Lab 2
test 3
...
 
**********  End Of Results  **********

# ./justdoit infile
input your value..= Users
Dou you want to save results to a file [y/n]? y
result file is 'Users.txt' in cur dir..

#!/bin/bash
[ ! -f $1 ] && echo "you must specify a current file e.g --> '$0 inputfile' " && exit 1
read -p "input your value..= " val
[[ ! $(grep -w "$val" "$1") ]] && echo -e "\nyour input does not appear in input file!!" && exit 1
x="sed -rn '/# '$val'/{n;:a;/# /!{N;ba};s/(.*)\n.*/\1/p}' $1"
read -p "Dou you want to save results to a file [y/n]? " c
case $c in
  y ) eval $x>${val}.txt ; echo "result file is '${val}.txt' in cur dir.." ;;
  n ) echo -e "\n**********  Results  **********\n$(eval $x)\n**********  End Of Results  **********" ;;
  * ) exit 1 ;;
esac