Define a new type of index object with a mapping of packets to the object given by the index-exp. The syntax of the expression is described in Expression Grammar.
The indxobj-type must not already be defined. Its name is case-insensitive, must be entirely composed of alphanumeric characters or the ’_’ character, and begin with an alphabetic character.
The index-exp must be syntactically correct, or an error is returned and the definition is ignored. If the index-exp contains any blanks, it must be surrounded by double quotes (“).
The <Unknown> index object has an index of -1, and the expression used to define a new index object should support recognizing <Unknown>.
For example, for index objects based on virtual or physical PC, the expression should be of the following form:
VIRTPC>0?VIRTPC:-1