Purge video cache script

I wanted to amuse myself with a Purge Video Cache script

purgeVideoCacche()
{
  // important (missing) code here
  alert("Burp!");
}

However, doing this does not show up on ScriptListener or as a recorded action (or menu item) making it difficult to guess what the code could be.

app.runMenuItem (stringIDToTypeID("anyonesguess"))

There is purge All (but it seems to be a separate menu item - so video is probably not included)

var idPrge = charIDToTypeID( "Prge" );
var desc28 = new ActionDescriptor();
var idnull = charIDToTypeID( "null" );
var idPrgI = charIDToTypeID( "PrgI" );
var idAl = charIDToTypeID( "Al  " );
desc28.putEnumerated( idnull, idPrgI, idAl );
executeAction( idPrge, desc28, DialogModes.NO );

 Any ideas or is this beyond the  realms of Photoshop scripting?