mind blowing!! I didnt explain the problem in detail but you got it almost right hats off to you. I admit my mistake. Actully I failed to reproduced the error as I made some changes in my code and it started working. Here is my tiny code: 
#!/usr/bin/perl -w
print"Pls enter the file name\n";
my $in=<STDIN>;

open(AA,"$in");
my $input='';
while(<AA>)
{
  my $temp='';
     $temp=$_;
   $input=$input.$temp;
}
close(AA);
open(BB,">out.txt");
print BB $input;
close(BB);

[download]
For my work I need read files and generate it in desired format, so I rely mostly on concatination as above. and error that is produced same as u stated. Pls tell me also what all mistakes I have done in this small piece of code.

In reply to Re^2: What is the right way of concatenating strings by cool
in thread What is the right way of concatenating strings by cool

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