The CResponse::getExpires function retrieve the current value of the Expires property.
Upon successful completion, an integer that indicates the minutes of expires is returned. Otherwise, a negative value is returned.
This function retrieves the current value of the Expires property of the object. If the user returns to the same page before it expires, the cached version is displayed. If this property is set more than once on a page, the shortest time is used.
If the property is never set before it is called, INT_MAX will be returned. In this case, the return value does not make sense.
The CResponse::setExpires function can be used to set a new value to the Expires property.
CResponse, CResponse::setExpires, CResponse::getExpiresAbsolute, CResponse::setExpiresAbsolute,