InitScript

This element contains an initialization script to be executed for the parent MovieClip element before any instances of the elements are referenced.
Note that initialization scripts can also be defined globally using the InitClipActions element. Any InitClipAction elements defined under that element will generate a warning but will override this definition.
InitScript actions are most commonly used to define ActionScript classes and to map ExportSymbol elements to ActionScript classes.
By default the script is expected as element content however the use of the optional 'src' attribute permits an external script to be identified using a URL. If this is specified then all element content is ignored.
Consult documentation on ActionScript for more information on scripting.