FFI: Pass a Smalltalk String as part of a Structure

> Hi,
>
> I defined an FFI Structure using
>
> MyStruc class>>fields
>     ^#( #path 'char*) )
>
> After calling define Fields I see that the wrappers are generated.
> However I not quite sure how to pass a Smalltalk String in.
>
> Something like
>
> MyStruc new path: '/home/udos/'
>
> does not work.
>
> Any pointers?
>
> CU,
>
> Udo
>
>
>

> Hi -
>
> You need to create an instance of ExternalData and pass this in. For
> example:
>
> setPath: aString
>   "Set the path in this structure from a Squeak string"
>   | xHandle xData |
>   xHandle:= ExternalAddress allocate: aString size+1.
>   1 to: aString size do:[:i| xHandle byteAt: i-1 put: (aString byteAt: i)].
>   xHandle byteAt: aString size put: 0.
>   xData := ExternalData fromHandle: xHandle type: ExternalType char
> asPointerType.
>   ^self path: xData
>
> Hope this helps,
>   - Andreas
>
>
> Udo Schneider wrote:
>> Hi,
>>
>> I defined an FFI Structure using
>>
>> MyStruc class>>fields
>>     ^#( #path 'char*) )
>>
>> After calling define Fields I see that the wrappers are generated.
>> However I not quite sure how to pass a Smalltalk String in.
>>
>> Something like
>>
>> MyStruc new path: '/home/udos/'
>>
>> does not work.
>>
>> Any pointers?
>>
>> CU,
>>
>> Udo
>>
>>
>>
>
>
>