In this case $txt results in a pretty big string with newlines. So I want to filter every line ...

If $txt is a big string with embedded newlines, then why are you using it to open a filehandle?

Wouldn't 

  foreach my $line ( split("\n", $txt) ) {
      # do something to filter $line
  }

[download]
do what you need?

In reply to Re: strings again by dws
in thread string truncation problem by techm

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