Change your while loop: 
 while (my $line = <$fh_in>)   {       
    my $text = $line;
    chomp ($text);  
    
    #Strip/remove whitespace between lines of text file;
    while (<STDIN>)
    {
      print if (!/^\s*$/);
    }
                     
    print $fh_out "$text\n";  #Save stripped results; 
         
  }

[download]
as follows: 
 while (my $line = <$fh_in>)   {       
     print $fh_out $line if (!/^\s*$/);
 }

[download]
Update: Sorry, I wrote that above message on my mobile device in the train commuting back to home, the train was arriving near my town, so I copied and pasted the code a bit to hastily. The above code should be: 
 while (my $line = <$fh_in>)   {       
     print $fh_out $line if $line !~ /^\s*$/;
 }

[download]
Update 2: I had not noticed when I wrote the first update above, but poj sent me a CB message proposing a very similar correction. Thanks to poj. Further update: I had also not seen that poj also posted the correction as an answer to your question, so that these updates end up not to be very useful...

Je suis Charlie.

In reply to Re: Remove whitespace between lines by Laurent_R
in thread Remove whitespace between lines by wrkrbeee

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