Re: [HPLIP-Devel] Bug: hplip =1.6.12 breaks support for the sane network daemon
Hello David, On Jul 24 19:24 Suffield, David wrote (shortened): This looks like a case where we don't necessarily follow the Sane specification. Since the old hpaio code ignored localOnly and seemed to work ok, I see no reason for not changing it back. Yesterday I did a very quick search what other backends in the SANE software do and it seems they usually ignore localOnly too. For your information I attached the gzipped output of for f in sane-backends-1.0.18/backend/*.c do echo $f grep local_only $f echo done It seems the net backend ist the only one which implements a test for local_only: if (local_only). Because of this I got the assumtion that perhaps local_only is only useful for the net backend to avoid that SANE devices with net are reported duplicated to the frontend. SANE devices with net can be also locally connected scanners (e.g. via USB) because saned and net can both run on localhost like on my workstation: --- # scanimage -L device `hpaio:/usb/HP_LaserJet_1220?serial=00XX' is a Hewlett-Packard HP_LaserJet_1220 all-in-one device `hpaio:/net/Officejet_7200_series?ip=10.10.100.100' is a Hewlett-Packard Officejet_7200_series all-in-one device `plustek:libusb:001:006' is a Canon N1240U/LiDE30 USB flatbed scanner device `net:localhost:hpaio:/usb/HP_LaserJet_1220?serial=00XX' is a Hewlett-Packard HP_LaserJet_1220 all-in-one device `net:localhost:plustek:libusb:001:006' is a Canon N1240U/LiDE30 USB flatbed scanner --- There is no good reason why there shouldn't be also a SANE device `net:localhost:hpaio:/net/Officejet_7200_series?ip=10.10.100.100' when I explicitely run saned and net on my workstation. Of course one could discuss why someone should run saned and net on his workstation for his locally connected scanners. Usually this is the easiest way to get user access in problematic cases (because saned runs as root) like for parallel port scanners or if someone might be fed-up with the udev/HAL/resmgr magic ;-) Kind Regards Johannes Meixner -- SUSE LINUX Products GmbH, Maxfeldstrasse 5, 90409 Nuernberg, Germany AG Nuernberg, HRB 16746, GF: Markus Rex foo.gz Description: output.gz - This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now http://get.splunk.com/___ HPLIP-Devel mailing list HPLIP-Devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/hplip-devel
Re: [HPLIP-Devel] Bug: hplip =1.6.12 breaks support for the sane network daemon
Hello, On Jul 24 00:18 Suffield, David wrote (shortened): Why would you use saned with a networked PS C5180? Since the PS C5180 is networked, you can use xsane from any PC without saned. I do not understand this. When a device is connected via ethernet, it is not sufficient to run only a scanning frontend (like xsane) to access it. When a device is connected via ethernet, it requires also to run the appropriate scanner driver (here HPLIP/hpaio) on the host from which it should be accessed. Asssume there is a HP all-in-one device with ethernet connection and there are several workstations in an office: With saned it should be sufficient when HPLIP/hpaio and saned runs only on one single workstation which is then the server for the HP all-in-one device and on all other workstations only the SANE net meta-backend runs so that users on the other workstations could access the device. According to SANE Standard v1.04, when localOnly is true during sane_get_devices, no remote devices are returned. This means only USB/Parallel devices are returned. Is there perhaps a misunderstanding what http://www.sane-project.org/html/doc012.html#s4.3.3 should actually mean? Of course on the one hand devices directly attached to the machine that SANE is running on is very clear (i.e. explicitely no devices with ethernet connection) but perhaps when it was written, they might have had only in mind to use local_only==false to suppress those SANE devices which are reported by the net meta-backend? I ask because I cannot imagine a good reason why a frontend should show only USB, SCSI and parallel port devices but not a device which is connected via ethernet. On the other hand I would understand why to suppress the SANE devices which are reported by the net meta-backend: The saned frontend is only interested in devices which are not already reported by the net meta-backend which may be active on the same host. Kind Regards Johannes Meixner -- SUSE LINUX Products GmbH, Maxfeldstrasse 5, 90409 Nuernberg, Germany AG Nuernberg, HRB 16746, GF: Markus Rex - This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now http://get.splunk.com/ ___ HPLIP-Devel mailing list HPLIP-Devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/hplip-devel
Re: [HPLIP-Devel] Bug: hplip =1.6.12 breaks support for the sane network daemon
Thanks everybody for your feedback. Now I have a better understanding of your
use case. This looks like a case where we don't necessarily follow the Sane
specification. Since the old hpaio code ignored localOnly and seemed to work
ok, I see no reason for not changing it back. It should be fixed in the next
hplip release.
-dave
-Original Message-
From: Hernan Pastoriza [mailto:[EMAIL PROTECTED]
Sent: Tuesday, July 24, 2007 6:10 AM
To: Suffield, David
Subject: Re: Bug: hplip =1.6.12 breaks support for the sane
network daemon
Hi Dave,
Thanks for answering.
My reason is simplicity and access control.We have the C5180
in a ghost network, only local to our server and through
saned and cups we provide access to the scanners and printers
to our users. In this sense, our C5180 and printers are only
local to the server but no to the clients.
We must setup some complicated routing in the server to make
the printers visible to the clients at the network level. And
no, I can not connect them by USB as there are several rooms apart.
I don't know who must care about our configuration, saned or
hplip. My first impression is that hplip.
I interpret that the localOnly is for those devices that are
not accessible through the sane net protocol, which is this
case as the control of the data through the wire is done by
hplip right?
Again I am not a developer just an user that tried to figure
out what happened. As I read in several mailing list I wasn't
the only one, and there were no clear answer to it (only:
stay with hplip 1.6.10...)
Thanks again for your time,
Hernán
Suffield, David wrote:
Hi,
Why would you use saned with a networked PS C5180? Since
the PS C5180
is networked, you can use xsane from any PC without saned.
According to SANE Standard v1.04, when localOnly is true during
sane_get_devices, no remote devices are returned. This means only
USB/Parallel devices are returned.
I would use saned if the all-in-one was USB connected only.
Then the
hpaio.c code should work correctly.
-dave
-Original Message-
From: Hernan Pastoriza [mailto:[EMAIL PROTECTED]
Sent: Friday, July 20, 2007 2:14 PM
To: hplip-devel@lists.sourceforge.net
Cc: [EMAIL PROTECTED]
Subject: Re: Bug: hplip =1.6.12 breaks support for the
sane network
daemon
I tracked down
this problem to the file:
scan/sane/hpaio.c
The function DevDiscovery(int localOnly) skips the
detection of cups
connected devices if localOnly is set. This flag is
passed as TRUE
by scaned, probably to avoid a loop with itself.
I think that hplip is misunderstanding this flag.
I just commented out the respective if (line 291 of hpaio.c in
hplip-1.7.4a)
and now it works.
This is very crude but in this way saned is working with
libsane-hpaio again.
I hope this helps.
Hernan
This is the patch:
diff -rup hplip-1.7.4a/scan/sane/hpaio.c
hplip-1.7.4/scan/sane/hpaio.c
--- hplip-1.7.4a/scan/sane/hpaio.c 2007-03-16
21:09:04.0 -0300
+++ hplip-1.7.4b/scan/sane/hpaio.c 2007-07-20 16:17:38.0
+++ -0300
@@ -288,7 +288,7 @@ static int DevDiscovery(int localOnly)
}
}
- if (!localOnly)
+ if (1)
{
cnt = GetCupsPrinters(cups_printer);
for (i=0; icnt; i++)
I've discovered a bug in hplip which makes it impossible to
share the
scanner of a networked HP Photosmart C5180 using the sane network
daemon (saned).
In theory saned is supposed to provide access to a
connected scanner
(using e.g. the hpaio backend). Each client on the network which
supports sane should now be able to connect to the server
running the
sane network daemon and access the server's scanners -
without needing
any special drivers (because the driver, hplip in my case
is installed
on the server).
And this setup worked well with all hplip versions up to 1.6.10.
I've tried many different distros now to get this feature
to work with
newer versions of hplip, but I was not successful:
Ubuntu 7.04 - hplip 2.7.6 - saned not working Gentoo
2006.1 - hplip
1.6.12 1.7.3 - saned not working Debian 4.0 - hplip
1.7.3 - saned
not working openSuSE 10.2 - hplip 1.7.3 - saned not working
Scanning (locally, on the server) and printing (locally and
over the
net using
cups) works fine in all cases.
Of course I am not using any firewall or other related
software/hardware which could block the saned
functionality (and it
works with 1.6.10).
For further details (output of saned, etc.) you might want
to take a
look at:
http://www.mail-archive.com/hplip-help%40lists.sourceforge.net/msg028
6
7.html
I am definitely _not_ the
