[sane-devel] Question about non-blocking

[Henning Meier-Geinitz]

Hi,

On Wed, Feb 26, 2003 at 09:30:08AM +1100, Martijn van Oosterhout wrote:
> SANE supports a backend being non-blocking. Does that mean "don't ever
> block" or "don't ever block for long periods of time"? For example, the
> warming up of the lamp can take a while so you'd like to support non-block
> for that. OTOH, we can't support non-block for the USB reads and writes. But
> they don't take very long.

The non-blocking mode is only relevant for sane_read. As warm-up is
ususally done in sane_start, it's not really relevant here.

Non-block means: if you have no data, return immediately. Blocking
means: Only return if you have at least one byte of data (or an error
occured).

Bye,
  Henning