[Mono-dev] PInvoke ques

[Robert Jordan]

Shankari,

> My aim is to prevent an update to a pass-by-ref
> value(this is a part of my work in fault isolation).
> My idea is to make a copy of the managed type , so
> this copy will be updated rather than the original
> one.

Well, as Zoltan told you: if the ref parameter is
marked with the [In] attribute, it won't be marshaled
back, at least not with SVN head.

> In order to do this , I need the size of the managed
> object. Does the instance_size denote  the size of the
> "managed object" ??

There is no need to reinvent the wheel. The code
is already there. In order to do this you have to mark
the parameter with the [In] attribute.

If you don't want to do this is your C# code, you may
somehow imply PARAM_ATTRIBUTE_IN to the "attrs" field
of the parameter. You can do this in emit_marshal_vtype,
somewhere after "case MARSHAL_ACTION_CONV_OUT".
Needless to say that you're breaking the runtime's
compatibility.

Rob