I would just use a regular expression: 
if ($line =~ m/([\0-\x8\xb-\x1f\x7e-\xff])/) {
  print "$line contains illegal character (ord: ", ord($1), ")\n";
}

[download]
The reason why your code isn't working is because instead of: 
  @character=split /\.*/;
  while (@character){

[download]
you really want: 
  @character=split //; # split $_ into single characters
  while (@character){

[download]
With the original split call, when there's a dot at the beginning of the line the first element of @character is the empty string.

In reply to Re: Rogue Null (ordinate 0) characters in text files by pc88mxer
in thread Rogue Null (ordinate 0) characters in text files by paulnovl

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