Shell Programming and Scripting

#!/bin/sh
file='/home/testfile1'
filesearch='/home/test00'
while read line
do
search=`echo $line |cut -c 1-24`
echo $search
echo `grep -n "" $filesearch|awk 'BEGIN { FS = ":" } ; { print $1 }'` >> linenbrs

done < $file;

cat testfile1
DISPLAY ' THIS IS FIRST LINE '
DISPLAY ' THIS IS SECOND LINE '' ITS CONTINUE '
DISPLAY ' THIS IS FOURTH LINE'

cat test00
DISPLAY ' THIS IS FIRST LINE '
DISPLAY ' THIS IS SECOND LINE '
' ITS CONTINUE '
DISPLAY ' THIS IS FOURTH LINE'

I WANT linenbrs FILE SHOULD HAVE LINE NUMBERS WHERE DISPLAY STARTED LIKE THIS :
$cat linenbrs
1
2
4

grep -n "$line" $filesearch