attribute set -- sets ( adds or overwrites ) an attribute of a file.

ATTRIBUTE SET Type$, Name$, Value$, Filename$
  Set the attribute Name$ of type Type$ for the file Filename$ with the string Value$.
  These are valid types:
  Type$ = "String|Int|Long|Double|Float|Mime|Bool"
  For Bool type attributes:
  Value$ = "true|false"

Attribute set sets, adds or overwrites, file attributes. The attributes can be strings, integer, long.double, or float numbers, or boolian true/false.