Hi all, Last year, we defined a protocol exposing the C Data Interface (schema, array and stream) in Python through PyCapsule objects and dunder methods `__arrow_c_schema/array/stream__` (https://arrow.apache.org/docs/format/CDataInterface/PyCapsuleInterface.html).
A bit earlier last year, we also expanded the C Data Interface with device capabilities: https://arrow.apache.org/docs/dev/format/CDeviceDataInterface.html. Combining those two, we are now proposing to expand the PyCapsule protocol to additionally support the C Device Data interface as well. - Issue where this is being discussed: https://github.com/apache/arrow/issues/38325 - PR with the changes to the PyCapsule specification: https://github.com/apache/arrow/pull/40708 - PR with an implementation for PyArrow: https://github.com/apache/arrow/pull/40717 We would welcome your feedback in the issue or PR. While the mechanics of the addition are quite straightforward (for example for `__arrow_c_array__`, we add an equivalent `__arrow_c_device_array__` which works exactly the same, except that the returned data capsule holds a ArrowDeviceArray struct instead of a ArrowArray struct), there is some discussion about the semantics, mostly around expectations on cross-device copies (disallow them, allow to copy implicitly, or provide a way to ask data on a specific device?). Best, Joris
