sub get_errors {
    my $file = $_[0];
    my $cont = do { local( @ARGV, $/ ) = $file; <> };
    <regexp auf $cont mit $_[1] hier>
    $1;
}

sub main {
    local @ARGV = @_;
    @ARGV = glob '<Dateiglob hier>' unless @ARGV;
    local $/ = "\n\n\n";
    [...]
    while (<>) {
        if (<regexp hier>) {
            $stat{$rtsdir}{'errors'}++;
            if ($opts{'errors'}) {
               
 my $error = get_errors($anotherfile, $case);
        [...]
            }
        next;
        }
        [...]
    }
}