Try this:

#!/usr/bin/perl

use warnings;
use strict;

use File::Find;

open my $logfilefsv, '>>', 'logfsv.txt' or die $!;

my $file = "Mark.txt";

open my $in_fh, '<', $file or die $!;
my @lines = <$in_fh>;
close $in_fh;

open my $out_fh, '>', $file or die $!;

print $logfilefsv @lines;

for my $line ( @lines ){
    $line =~ s/N/M/gi;
    print $out_fh $line;
}

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In reply to Re: Search Replace String Not Working on text file by stevieb
in thread Search Replace String Not Working on text file by msstein

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