Re: [cffi-devel] shareable-byte-vectors for Allegro

On Mon, Jan 19, 2009 at 5:50 AM, John Fremlin jf@msi.co.jp wrote:

The advantage of the change is that ptr-var is now actually a foreign pointer as it is in all other cffi-ports.

You might not want to pass the ptr-var directly to a function, but actually use it as a foreign pointer.

For a concrete example, using the recvmsg(2) system call, you pass a structure containing an iovec, which is itself a structure containing the base address and length of the buffer into which the message body should be written.

That definitely looks like a legitimate use-case. Let us know when you figure out what the first argument to FF:FSLOT-ADDRESS-TYPED should be.