#!/usr/bin/perl -w
use strict;
my $stime = time();
my $filename = "file";
my $tempfile = "temp";
my $line;
open(OLD, "< $filename") or die "can't open $filename: $!";
open(NEW, "> $tempfile") or die "can't open $tempfile: $!";
while ($line = <OLD>) {
        # a code block to evaluate the current line 
        # and possibly update it goes here
	print NEW $line or die "can't write $tempfile: $!";
}
close(OLD) or die "can't close $filename: $!";
close(NEW) or die "can't close $tempfile: $!";
rename($filename, "$filename.bak") or die "can't rename $filename: $!";
rename($tempfile, $filename) or die "can't rename $tempfile: $!";
my $ftime = time();
my $etime = $ftime - $stime;
print "$etime\n";

$stime = time();

open(DATA,"$filename") or die "can't open $filename: $!";
my @data = <DATA>;
my @vads;
close(DATA)or die "can't close $filename: $!";
foreach $line (@data) {
        # a code block to evaluate the current line 
        # and possibly update it goes here
	push(@vads,$line);
}
open(DATA,">$filename") or die "can't open $filename: $!";
foreach $line (@vads) {
	print DATA $line;
}
close(DATA) or die "can't close $filename: $!";
$ftime = time();
$etime = $ftime - $stime;
print "$etime\n";