On Mon, 9 Feb 2009, Peter Walker wrote:

> Is this the norm, meaning i cannot use exceptions in the callback functions?

The callback functions are pure C functions, there are no exceptions in C.

> If so, how do I indicate this error back to the calling application.

By returning the right return code you make the transfer fail. If you want to
provide something specific back from the callback I suggest you use the
user-provided pointer.

-- 
  / daniel.haxx.se