open (FILE," $htmlfile") || die "Cannot open HTML file for parsing!: $
+!\n";
while(<FILE>) {
  $content="$content$_\n";
}
close(FILE);

[download]
This construct is not ideal. You are interpolating the variable $content into a new string for every line. You should use concatenation and just append to the string: 
while(<FILE>) {
  $content .= "$_\n";
}

[download]
But what you are doing now is slurping in the whole file and adding an extra newline at the end of each line (for which I see absolutely no reason). The same thing can be achieved by undefing $/ like this: 
{
  local $/; # undefs $/ for this block of code only

  open (FILE," $htmlfile") || die "Cannot open HTML file for parsing!:
+ $!\n";

  $content = <FILE>; # reads in whole file

  $content =~ s/\n/\n\n/g; # if really necessary to duplicate newlines

  close(FILE);
}

[download]

-- Hofmator

In reply to Re: Re: appending a unique marker to each url in a file by Hofmator
in thread appending a unique marker to each url in a file by cat2014

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