[sane-devel] Doubt about sane_get_devices

[m. allan noah]

On 4/26/08, m. allan noah <kitno455 at gmail.com> wrote:
> well, it appears that the sanei_usb support library intentionally does
>  not re-gather the list of devices. This makes sense in the average
>  sane installation, cause dozens of backends each gather the list
>  within a fraction of a second, as the dll backend cycles thru them.
>
>  in your case, it is the wrong behaviour, since the long-running daemon
>  needs to know the list has changed. I think i can change the current
>  code to retry occasionally.

I have just committed a fix to sanei_usb_init() which will run the
probe at most once per second, instead of once per process. The
backend must call sanei_usb_init() during sane_get_devices(), which
required an update to the fujitsu backend. This fixes the hotplugging
problem for me.

However, it does not yet fix the hot _UN_ plugging problem, as the
fujitsu backend does not yet prune removed devices from the list. That
is a more invasive change, so i need to test it some.

Other backends likely need these two changes done as well, I've not looked.

allan
-- 
"The truth is an offense, but not a sin"