By uploading selected properties to your server, you can enable clients to obtan those properties even when you are off-line. To upload or clear a property, simply send a SET_PROP message.
The format for a SET_PROP message is:
SET_PROP (property|property_and_value)
where
| property | is a PLAIN envelop whose data field names only the property and |
| property_and_value | is a PLAIN envelop whose data field names both the property and its value. |
The contents of property_and_value's data field is formatted as follows:
property=value
where, of course, property is the name of the property and value is its value. The manner in which the value is represented depends on the property, and is defined individually for each property. It may be text or binary.
If a property by the same name is already stored in the server, its value will be replaced. If the envelop contains only the property name and is not followed by an equals sign or a value, then the property will be cleared from the server's memory. To set a property to the empty string, include the equals sign but do not append a value.
If the property name begins with an underscore (_), it will be considered a private property which other clients will not be allowed to query. Your client can use private properties to store private data, such as your contact list. (Storing your contact list on the server, instead of your local file system, for example, would allow you to have access to your contact list regardless of the location from which you are connecting.)