By sending a TX_PROP_QUERY message, your client can look up another client's property. Although the server promises reliable delivery of the query, sending a TX_PROP_QUERY message does not guarantee that you will receive a response, since the client you are querying can choose to ignore you entirely.
The format of a TX_PROP_QUERY message is:
TX_PROP_QUERY tag address property
where
| tag | is a unique label for this message; |
| address | is the address of the user whose property you are querying; and |
| property | is an envelop whose data field names the property being queried. |
See "Querying Properties" for a list of properties that can be queried.
For privacy reasons, the client being queried is given complete control over which properties it reveals to which requesting parties. For example, some clients may refuse to reveal their ONLINE status to clients not listed in their own contact lists, or they may only reveal their email addresses to clients that sign their requests with verifyable signatures.
Sending this message will cause the other client to receive an RX_PROP_QUERY message.