my $fh = Symbol::gensym();
    open $fh, '+<$Conf[1]' or warn "$!";
    binmode $fh;

    my $size = 4096;

    seek $fh, -$size, 2;
    # Locate the end of the file
    while (1) {
    $cur_pos = tell $fh;
    read $fh, $buf, $size;
    last if $buf =~ m/\S/s;
    seek $fh, -$size*2, 1;
    }

    $buf =~ m/(\s*)$/s;
    $cur_pos += $-[0] || 0;

    truncate $fh, ++$cur_pos if $cur_pos;
    
    close $fh;
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Thanks again