What name should give under app/etc/module.xml file

Question

we have custom module with following files.

etc/config.xml

<config>
    <modules>
            <Magetechno_CancelCouponcode>
                    <version>0.1.0</version>
            </Magetechno_CancelCouponcode>
    </modules>
    <global>
        <models>
            <cancelcouponcode>
                <class>Magetechno_CancelCouponcode_Model</class>
            </cancelcouponcode>
    </models>
    <events>
        <sales_order_payment_cancel>
        <observers>
          <cancelcouponcode_observer>
            <type>singleton</type>
            <class>Magetechno_CancelCouponcode_Model_Observer</class>
            <method>cancel</method>
          </cancelcouponcode_observer>
        </observers>
        </sales_order_payment_cancel>    
    </events>
    </global>
</config>

model/observer.php

<?php
class Magetechno_CancelCouponcode_Model_Observer
{
public function cancel($observer)
{
  $event = $observer->getEvent();
  $order = $event->getPayment()->getOrder();
  if ($order->canCancel()) {
    if ($code = $order->getCouponCode()) {
      $coupon = mage::getModel('salesrule/coupon')->load($code,'code');
      if ($coupon->getTimesUsed() > 0) {
        $coupon->setTimesUsed($coupon->getTimesUsed()-1);
        $coupon->save();
      }
      $rule = Mage::getModel('salesrule/rule')->load($coupon->getRuleId());
      if ($rule->getTimesUsed() > 0) {
        $rule->setTimesUsed($rule->getTimesUsed()-1);
        $rule->save();
      }
      if($customerId = $order->getCustomerId()) {
        if ($customerCoupon = Mage::getModel('salesrule/rule_customer')->loadByCustomerRule($customerId, $rule->getId())) {
          $couponUsage = new Varien_Object();
          Mage::getResourceModel('salesrule/coupon_usage')->loadByCustomerCoupon($couponUsage, $customerId, $coupon->getId());

          if ($couponUsage->getTimesUsed() > 0) {

            /* I can't find any #@$!@$ interface to do anything but increment a coupon_usage record */
            $resource = Mage::getSingleton('core/resource');
            $writeConnection = $resource->getConnection('core_write');
            $tableName = $resource->getTableName('salesrule_coupon_usage');
       Mage::log($couponUsage->getTimesUsed());
       Mage::log("Coupon used time above");
      if($couponUsage->getTimesUsed()==1)
    {
        $__condition1 = array($writeConnection->quoteInto('coupon_id=?',$coupon->getId()));
        $__condition1 = array($writeConnection->quoteInto('customer_id=?',$customerId));
        if($writeConnection->delete('salesrule_coupon_usage', $__condition1))
            Mage::log("Its deleted from salesrule_coupon_usage");
        $__condition2 = array($writeConnection->quoteInto('rule_id=?',$rule->getId()));
        $__condition2 = array($writeConnection->quoteInto('customer_id=?',$customerId));
        if($writeConnection->delete('salesrule_customer', $__condition2))
            Mage::log("Its deleted from salesrule_custome");

    }
    else
    {
            $query = "UPDATE {$tableName} SET times_used = times_used-1 " .
              " WHERE coupon_id = {$coupon->getId()} AND customer_id = {$customerId} AND times_used > 0";

            $writeConnection->query($query);
        Mage::log("We have updated it");
    }
          }
          if ($customerCoupon->getTimesUsed() > 0) {
            $customerCoupon->setTimesUsed($customerCoupon->getTimesUsed()-1);
            $customerCoupon->save();
        //Mage::log('setTimesUsed customer saved Rule Time used');
          }
        }
      }
    }
  }
}
}

but we dont have app/etc/module_name/module.xml file. we created as below. but we dont know what name to give instead of Module_name text in below file to get the result of the module.

app/etc/modules/Module_Name.xml

<?xml version="1.0"?>
<config>
    <modules>
        <Module_name>
            <active>true</active>
            <codePool>local</codePool>
        </Module_name>
    </modules>
</config> 

Answer 1

Replace Module_name with Magetechno_CancelCouponcode

app/etc/modules/Magetechno_CancelCouponcode.xml

<?xml version="1.0"?>
<config>
    <modules>
        <Magetechno_CancelCouponcode>
            <active>true</active>
            <codePool>local</codePool>
        </Magetechno_CancelCouponcode>
    </modules>
</config> 

Answer 2

Here module_name is your custom module name,

Its Module entry point,

Magetechno_CancelCouponcode.xml

so you have to keep Package_Modulename with your Package and module name.

Remainng all files are same.

If this file is not defined your module is not works or not display inside site.

Change Module_name with Magetechno_CancelCouponcode

<?xml version="1.0"?>
<config>
    <modules>
        <Module_name>
            <active>true</active>
            <codePool>local</codePool>
        </Module_name>
    </modules>
</config>