[sane-devel] SCX-3405W scans with usb but not when shared from Linux Mint

[Ralph Little]

Hi,

On 2020-05-19 11:20 a.m., vicki at thepenguin.org wrote:
> On 2020-05-19 9:27 a.m., vicki at thepenguin.org wrote:
>> The output from the scanimage command is:
>>
>> home-E7250:~$ SANE_DEBUG_NET=50 scanimage -L
>> [sanei_debug] Setting debug level of net to 50.
>> [net] sane_init: authorize != null, version_code != null
>> [net] sane_init: SANE net backend version 1.0.14 (AF-indep+IPv6) from 
>> sane-backends 1.0.27
>> [net] sane_init: Client has little endian byte order
>> [net] sane_init: searching for config file
>> [net] sane_init: done reading config
>> [net] sane_init: evaluating environment variable SANE_NET_HOSTS
>> [net] sane_init: evaluating environment variable SANE_NET_TIMEOUT
>> [net] sane_init: done
>> [net] sane_get_devices: local_only = 0
>> [net] sane_get_devices: finished (0 devices)
>> [net] net_avahi_browse_callback: CACHE_EXHAUSTED
>> [net] net_avahi_browse_callback: ALL_FOR_NOW
>>
>>
> You could also try (on the laptop):
>
> SANE_NET_HOSTS=192.168.1.16 scanimage -L
>
> ... replacing the IP with that of your main machine.
> This should explicitly add the IP to the list of hosts that would be
> considered in addition to what is configured.
> I just tried that and it worked for me.
>
> Cheers,
> Ralph
>
> Okay, here is the net.conf file:
>
> home-E7250:~$ sudo cat /etc/sane.d/net.conf
> # This is the net backend config file.
>
> ## net backend options
> # Timeout for the initial connection to saned. This will prevent the 
> backend
> # from blocking for several minutes trying to connect to an unresponsive
> # saned host (network outage, host down, ...). Value in seconds.
> # connect_timeout = 60
>
> ## saned hosts
> # Each line names a host to attach to.
> # If you list "localhost" then your backends can be accessed either
> # directly or through the net backend. Going through the net backend
> # may be necessary to access devices that need special privileges.
> # localhost
> #
> 192.168.0.15
>
> And when I ran the command:
>
> home-E7250:~$ SANE_NET_HOSTS=192.168.0.15 scanimage -L
>

This is really weird.

One thing I should ask: have you built SANE on the laptop from sources?
Is there a possibility that there is a mixture of package and locally 
built objects on there?

Assuming not... we continue... :D

If the IP is in the config file, we should be seeing something like:

[net] sane_init: searching for config file
[net] add_device: adding backend 192.168.0.15
[net] add_device: backend 192.168.0.15 added
[net] sane_init: done reading config

...as the backend parses the config file. That's what I don't understand 
about what we are seeing.

Could you give us the debug of scanimage when you specify the IP via the 
environment variable?

SANE_DEBUG_NET=50 SANE_NET_HOSTS=192.168.0.15 scanimage -L

We should expect to see something like:

[net] sane_init: evaluating environment variable SANE_NET_HOSTS
[net] sane_init: trying to add 192.168.0.15
[net] add_device: adding backend 192.168.0.15
[net] add_device: backend 192.168.0.15 added

It might also be useful to see the output of this:

SANE_DEBUG_DLL=10 scanimage -L

...to make sure we are getting the right binaries.

Cheers,
Ralph