Igor: I tried what you said but I get the same error. Here is more information:

The C function is like this:

int *odbx_result*(
    odbx_t* *handle*,
    odbx_result_t** *result*,
    struct timeval* *timeout*,
    unsigned long *chunk* )


My method with FFI is this:

apiQueryResult: connectionHandle handle: handle timeout: timeout chunk:
chunk
    <cdecl: long 'odbx_result' (ulong ulong* DBXTimeSpec ulong) module:
'opendbx'>
    ^self externalCallFailed

And DBXTimeSpec has 2 attributes (seconds y nseconds). It has this class
message:

DBXTimeSpec
fields
    ^#(
        (seconds         'long')
        (nseconds    'long'))


Many thanks,

Mariano



On Wed, Sep 17, 2008 at 2:02 AM, Igor Stasenko <siguctua at gmail.com> wrote:

> 2008/9/17 Mariano Martinez Peck <marianopeck at gmail.com>:
> > Hi everybody!
> >
> > I need to call a C function with a NULL value in one of the parameter. I
> > tried to send it a nil but I got an error in FFI when trying to call that
> > function. The error is: "cannot coerce arguments". Obviously this error
> says
> > FFI cannot map from nil to null.
> >
> > Do someone know how can I do this?
> >
> you mean C's NULL?
> AFAIK it defined as
> #define NULL 0
>
> so, in squeak you can simply pass 0.
>
> > many thanks,
> >
> > mariano
> >
> >
> >
> >
>
>
>
> --
> Best regards,
> Igor Stasenko AKA sig.
>
>
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