[sane-devel] Error messages when starting "scanimage"

[Louis Lagendijk]

On Wed, 2018-06-06 at 18:32 +0200, Dr Rainer Woitok wrote:
> Greetings,
> 
> whenever I'm starting "scanimage" I get a bundle of error messages:
> 
> $ SANE_CONFIG_DIR=$HOME/.config/sane scanimage --device
> pixma:MX880_192.168.2.199 -T
> [bjnp] udp_command: ERROR - no data received (timeout = 1000)
> [bjnp] bjnp_init_device_structure: Cannot read mac address, skipping
> this scanner
> [bjnp] udp_command: ERROR - no data received (timeout = 1000)
> [bjnp] add_scanner: ERROR - Cannot read scanner make & model:
> bjnp://new-host.local:8612/timeout=1000
> [bjnp] udp_command: ERROR - no data received (timeout = 1000)
> [bjnp] bjnp_init_device_structure: Cannot read mac address, skipping
> this scanner
> [bjnp] udp_command: ERROR - no data received (timeout = 1000)
> [bjnp] add_scanner: ERROR - Cannot read scanner make & model:
> bjnp://new-host.local:8612/timeout=1000
> 
> $ ls -l $HOME/.config/sane
> total 8
> -rw------- 1 rainer rainer    6 2017-10-27 13:01 dll.conf
> -rw------- 1 rainer rainer 1053 2018-06-06 17:54 pixma.conf
> $ more $HOME/.config/sane/dll.conf 
> pixma
> $ grep -v '^#' $HOME/.config/sane/pixma.conf 
> bjnp-timeout=100
> bjnp://192.168.2.199/timeout=5000
> bjnp-timeout=100
> $
> 
> The name "new-host.local" was assigned to my scanner/printer by my
> rout-
> er, and I have not yet found a way to change it to something
> reasonable.
> But it refers to the same  IP address 192.168.2.199  which I also use
> in
> the "scanimage" command.
> 
> What is causing  these error messages  and how can I prevent
> them?   And
> why is  "scanimage"  using the  default timeout of 1000  rather than
> the
> configured timeout of 100?
> 
> Sincerely,
>   Rainer

Before we jump into the timeout issue, let's first get the basics
sorted out:
- what does a simple "scanimage -L" report?
- Is there a firewall in place on the computer, and if so,did you open 
port 8612 (TCP and UDP in and out), see man sane-pixma. 

How do you connect to the scanner? Timeout 1000 (1 sec) is ok for a
wired connection, for WIFI it should most likely be higher anyhow.
But lets keep things simple for now, so make sure the scanner works
with default settings for the normal pixma.conf settings (most likely
in /etc/sane.d) first.

I will have a look at the other details when I have some time (I need
to fix my Domoticz and am working on cups-bjnp at the moment).

BR, Louis