Page Comparison

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• 0 (Advertisement) – Indicates the receipt of an SSDP multicast message, which can be either a NOTIFY message or an M-SEARCH message. The GetObject() method  method will return an associative array with all SSDP headers and an "ssdpType" key, which can have a value of either "m-search" or "notify".
• 1 (Search response) – Indicates that the message is a response to an roUPnPControllor.Search() request. The The GetObject() method  method will return an associative array with all headers from the HTTP M-SEARCH response.
• 2 (New device added to the device list) – Indicates that the roUPnPController object has detected a new device and added it to the device list, which is maintained internally. Device detection can result from receiving either an ssdp:alive message  message or a response to an M-SEARCH message. The The GetObject() method  method will return an roUPnPDevice instance containing information about the added device. This message type is only delivered once per new device. Once a device is part of the device list, subsequent M-SEARCH requests will only return type 1 (Search response) values for that device.
• 3 (Device will be deleted from the device list) – Indicates that a device will be deleted from the device list, which is maintained internally. A device is deleted from the list when the player receives an ssdp:byebye message from the device, when the device does not send an an ssdp:alive message  message within the defined "max-age" interval, or when the device is forcibly removed using the roUPnPController.RemoveDevice() method. The The GetObject() method  method will return an roUPnPDevice instance containing information about the device to be removed.

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