A linking element's xlink:actuate attribute has two possible values:
user
auto
<IMAGE
xmlns:xlink="http://www.w3.org/XML/XLink/0.9"
xlink:type="simple" xlink:href="logo.gif"
xlink:actuate="auto"/>
Like all attributes in valid documents, the actuate attribute must be declared in the DTD in a <!ATTLIST> declaration for the link elements in which it appears. For example:
<!ELEMENT IMAGE EMPTY>
<!ATTLIST IMAGE
xmlns:xlink CDATA #FIXED "http://www.w3.org/XML/XLink/0.9"
xlink:type CDATA #FIXED "simple"
xlink:href CDATA #REQUIRED
xlink:show (new | replace | parsed) #IMPLIED "parsed"
xlink:actuate (user | auto) #IMPLIED "auto"
>