Re: [libmicrohttpd] Zero copy MHD_create_response_from_callback

[Christian Grothoff]

On 11/17/22 20:34, Dan Inve wrote:
>   Hi Christian,
>
> Sounds like you should be using MHD_create_response_from_iovec(). That
> > way, you can avoid the memcpy() entirely.
>
> I took a look at MHD_create_response_from_iovec, but I'm not sure if that
> works for my circumstance because it doesn't use a callback. The data from
> the driver isn't available immediately, so I check for the status inside of
> the MHD_ContentReaderCallback and will suspend the connection if the next
> 64MB block isn't ready. When the next data block is ready I resume the
> connection. Am I missing some way of doing that with
> MHD_create_response_from_iovec? :)

Ah, I see: async generation PLUS iovec.  Yep, that's indeed not (yet) 
possible. I don't see an issue with supporting this in principle, but 
it's simply not been implemented. If you have time to add it, I'm sure 
we'd accept a (well-written) patch ;-).

Happy hacking!

Christian