Fatal error: Call to undefined function read_config_option

[mannycr86]

Hi, I'm really new at this, and I was trying to get win services running but I'm getting this error.
Found index: Fatal error: Call to undefined function read_config_option() in /var/www/html/lib/snmp.php on line 268

This is the line referring to this snmp.php file,
/* determine default retries */
if (($retries == 0) || (!is_numeric($retries))) {
$retries = read_config_option("snmp_retries");
if ($retries == "") $retries = 3;

what should I do to fix this?