use strict;
use warnings;
open(my $fh, '<', "$file") or die $!;#use three argument open
my $previous_line = q{}; #initially previous line would be empty
while(my $current_line = <$fh>){
  chomp;
  print"$current_line\n";
  print"$previous_line\n";
#assign current line into previous line before it go to next line
  $previous_line = $current_line; 
}
close($fh);

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In reply to Re: How to get previous line of the file while processing current line in while loop by Nikhil Jain
in thread How to get previous line of the file while processing current line in while loop by shan_emails

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