Could you explain what you mean with a paragraph of text?

You mean lines of text seperated by an empty line, you could do something like this to read a file by paragraph:

{ # create an extra scope
  local $/ = ""; # set record seperator to empty lines
  while (<INPUT>) {
      # $_ contains a paragraph of text from <INPUT>
  }
} # $/ is restored to its original value
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Note that this code will tread more than one blank line as a single separator. See also the section $INPUT_RECORD_SEPARATOR in perlvar.