I have a huge file > 3GB. It has multiple records with header and footer. Header and footer are fixed length. 50 and 30 characters long respectively. I need to remove those headers and footers from the file. I am a shell script guy and new to PERL. I read through some tutorials, played around a bit. I tried samples like the one below to find a character and delete. headers always start with HDR and footers start with FTR

use strict;
use warnings;

$^I = '.bak'; # create a backup copy 

while (<>) {
   s/HDR//g; # do the replacement
   print; # print to the modified file
}
[download]

this delete the entire line not just the 50 characters Also, i am testing witha small file (3KB) and the while stores the file content in a variable. I am guessing it would be an issue for a file 2GB size. any suggestions on where i can go from here. Please help and hello the forum. This is going to be my home for the next few monhts.

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