PropertyHandle :: IsWrite - Can instance be updated
When an instance has been selected for the property handle, the function returns whether the instance can be updated (YES) or not. The instance cannot be updated for several reasons:
1. The property handle is opened for read, only
2. The instance is persistent write protected
3. The instance is locked by another user
4. The current applications does not have rights for updating the instance
5. The instance is an embedded part of another instance which cannot be updated
Return value: Return value ( logical )
The function returns YES when the question was answered positively. Otherwise it returns NO.