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

[Dr Rainer Woitok]

Louis,

sorry for the delay ...  due to other obligations  it took me a while to
get back to this problem ...

On Wednesday, 2018-06-06 23:12:24 +0200, you wrote:

> ...
> Before we jump into the timeout issue, let's first get the basics
> sorted out:
> - what does a simple "scanimage -L" report?

$ scanimage -L

No scanners were identified. If you were expecting something different,
check that the scanner is plugged in, turned on and detected by the
sane-find-scanner tool (if appropriate). Please read the documentation
which came with this software (README, FAQ, manpages).
$ SANE_CONFIG_DIR=$HOME/.config/sane scanimage -L
[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
device `pixma:MX880_192.168.2.199' is a CANON Canon PIXMA MX880 Series multi-function peripheral
$

> - 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. 

None that I knew of:

$ grep -v '^#' /etc/hosts.allow /etc/hosts.deny
/etc/hosts.allow:
/etc/hosts.deny:
$

> How do you connect to the scanner?

Sorry, I forgot to mention that in my initial mail.  The scanner is con-
nected via WiFi.

>                                    Timeout 1000 (1 sec) is ok for a
> wired connection, for WIFI it should most likely be higher anyhow.

That's why for the scanner itself the timeout was  set to 5000 millisec-
onds (see below).  The timeout of 100 milliseconds was intended to apply
to anything else.

> 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.

Well, "/etc/sane.d/pixma.conf" only contains comments, and my personal
configuration file only contains the aforementioned timeouts:

$ grep -v '^#' /etc/sane.d/pixma.conf
$ grep -v '^#' ~/.config/sane/pixma.conf
bjnp-timeout=100
bjnp://192.168.2.199/timeout=5000
bjnp-timeout=100
$

When I comment out  the two general  timeouts of  100 milliseconds in my
personal configuration file, I'm getting the same result, but when I use
the global configuration file, I'm getting a total failure:

$ grep -v '^#' ~/.config/sane/pixma.conf
bjnp://192.168.2.199/timeout=5000
$ 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
scanimage: scanning image of size 638x877 pixels at 24 bits/pixel
scanimage: acquiring RGB frame, 8 bits/sample
scanimage: reading one scanline, 1914 bytes...	PASS
scanimage: reading one byte...		PASS
...
scanimage: stepped read, 3 bytes... 	PASS
$ 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
scanimage: open of device pixma:MX880_192.168.2.199 failed: Invalid argument
$

So when I use my personal configuration file the scanner IS working, ex-
cept for these annoying error messages.

Sincerely,
  Rainer