FFI and pointers

Ruby
1

Hello,

I’m playing around with FFI and encountered a problem, I could not solve
till now.
Let’s assume I use standard C’s malloc in my wrapper:

attach_function :malloc, [:int], :pointer

so far no problem. But what now? The pointer returned is of type void*,
which is of no help, since I need double*, int* and float* …
Is there a type cast mechanism in FFI (or anything similar) or do I have
to wrap
the original library in another layer of C (alternatively write a helper
lib…)
Or can I import C’s typecasts using FFI itself?

Best regards,
Thorsten

2

Thorsten H. wrote:

Is there a type cast mechanism in FFI (or anything similar) or do I
have to wrap
the original library in another layer of C (alternatively write a
helper lib…)
Or can I import C’s typecasts using FFI itself?

Best regards,
Thorsten

If nothing else, you can use the read_* and write_* methods (like
read_int) to interact with it.

-Justin

3

Well, the problem is not to use the pointer type as such, but
compatibility issue.
I have this function behaving like malloc, and other functions
which take pointers to - let’s say - float.
Since malloc returns void* I suspect the problems I experience
are due to this mismatch.

Justin C. schrieb: