Logiweb(TM)

13.3.10 Update attributes

Prev Up Next Page 437 of 800 Search internet


Attributes of type 0 are cardinals stored as little endian byte vectors. Each cardinal equals an attribute type and the associated time stamp equals the server time the attribute list of the given type was last modified. Attributes of type 0 can have one of the values 1, 2, 3, 4, or 5. Attributes of type 0 are referred to as 'update' attributes.

Whenever the attribute list of type n (for some n>0) is modified, the change is noted in the update attribute list. That gives rise to a change of the update attribute list itself, but the latter change is not noted in the update attribute list.

If an attribute list of type n (for some n>0) becomes empty, then the change can be noted in one of two ways: (1) An update attribute with value n is created with the current server time as timestamp. (2) The update attribute with value n is deleted and an update attribute with value 0 is created with the current server time as timestamp. The present server implementation never uses the latter option and, hence, update attributes cannot have value 0.

Prev Up Next Page 437 of 800 Search logiweb.eu

Copyright © 2010 Klaus Grue, GRD-2010-01-05