my $start_delim = qr/<\!--text[se]\d{3}-->/;
my $end_delim = qr/<\!--texte/;
while (<$prfore>) {
  if (/$start_delim/) {
    do {
      $_ = <$prfore>;
    } while !eof and /$start_delim/;

    for ( ; !eof and !/$end_delim/; $_ = <$prfore>) {
      s/\D{5}\s+$/\n/;
      $linevalis .= $_;
    }
  }
}