modify-attr
Specifies the attribute values to modify for the modify command or event.
Each <modify-attr> element must contain at least one <add-value>, <remove-all-values> or <remove-value> element.
<!ELEMENT modify-attr (remove-value |
remove-all-values |
add-value)+>
<!ATTLIST modify-attr
attr-name CDATA #REQUIRED>
<!ELEMENT remove-all-values EMPTY>
<!ELEMENT remove-value (value+)>
<!ELEMENT add-value (value+)>