gnome print manager dosn't see valid printer queue

Simon Bridge · 05-21-2005, 08:59 AM

I have a laserjet IIIp (wPCL5) on lp0, it configures fine and I can print a cups test page OK. However, the gnome print manager insists that "no printer detected" and wants to start the printer configuration wizard.

I havn't tried this logged in as root, so it may be a permission problem. However, it has been going before - I'll get to that in a bit.

On command line, if I try:

$ lpr /dev/lp0 test.txt

I get: "permission denied" ... well OK so:

# lpr /dev/lp0 test.txt

and I get: "lpr: error - scheduler not responding!"

However, if I try it this way:

$ lpr -P laserjet3p test.txt

It prints away and generally looks innocent.

Interestingly, the last printing I did was via dvips thus:

$dvips mybook.dvi

which worked fine then, but gives me

Code:

This is dvips(k) 5.92b Copyright 2002 Radical Eye Software (www.radicaleye.com)
' TeX output 2005.05.08:1956' -> |lpr
lpr: error - scheduler not responding!
<texc.pro>Broken pipe

though it works fine with:

$ dvips -P laserjet3p mybook.dvi

I'm pretty sure this is a clue!

Now - it's been a while since I printed anything. Two major changes have occured since:

1. Network set up - with NFS shares. This computer is the server.
2. Mozilla Firefox installed

Now Firefox had the famouse "cannot print" trouble - which I was testing when I found that the print manager couldn't detect the printer queue. However, I got firefox to print by replacing the default print command with "lpr -P laserjet3p".

So - I understand why lpr /dev/lp0 gives permission denied - but why cannot the print server see the printer dammit!

Tinkster · 05-22-2005, 07:23 PM

Well - what to say mate? :)

I suggest reading
man lpr

CUPS has never intended for you to try and use a
raw device in the first place, what it's trying to do (I
assume that this is what happens) to queue the CONTENT
of /dev/lp0 to the QUEUE.

For all I know the only "problem" you may have that
there's no default queue defined within CUPS, in which
case a
$dvips mybook.dvi
would fail indeed.

Cheers,
Tink

Simon Bridge · 05-23-2005, 02:36 AM

Sure - have read lpr man page - as well as the associated pages.
For eg.

Code:

# lpstat -p
lpstat: get-printers failed: client-error-forbidden

I have gone through the regular FC printer setup - and checked the printer as default and still Gnome Print Manager says there are no printers.

There is still a possibility this is a permissions problem - but what is this "scheduler" thing?

The command from the print-manager launcher says "tryprint.pl %F" so I guess I go look for that perl script ...

Code:

$ ls -l tryprint.pl
-rwxrwxr-x  1 root root 8891 Dec 18  2003 tryprint.pl

This is 0775 - still didn't work with 0777 so I put it back.

Looking thorugh the script, I see there is an optional logfile commented out. With the logfile enabled, I redid the printer config ... here's what got stuck in /tmp/tryprint.log

Code:

Got -1 arguments to try doing something with

This comes from the very first part of the script:

Code:

$title = "--title \"Desktop Print Dialog\"";
$printer_list = "";

$homedir = $ENV{'HOME'};

open(LOG, ">/tmp/tryprint.log");
#open(LOG, ">/dev/null");

print LOG "Got $#ARGV arguments to try doing something with\n";

if ($#ARGV < 0) {
    # assume that they are trying to manage queues
    #$msg = "You passed no files to print, starting print queue manager.";
    #$foo = `gdialog $title --infobox "Your print request could not be completed for the following reason: $msg" 40 40 2>&1`;
    `gnome-print-manager`;
    exit;
}

So I try looking for "gnome-print-manager":

Code:

$ man gnome-print-manager
No manual entry for gnome-print-manager
$ gnome-print-manager
lpstat: get-printers failed: client-error-forbidden

So the first thing that happens is that the print manager asks lprstat and, as we know, lprsts is not allowed to look ... where? Presumably there's a config file of some kind that lprstat look in?

It did occur to me that this may be trouble from deleting the first line in /etc/hosts ... so I restored the line:

Code:

127.0.0.1 lo loopback

- shut down the network services - started them up again - still no joy.

Simon Bridge · 05-23-2005, 03:12 AM

Googling the error message (lpstat: get-printers failed: client-error-forbidden) I end up with
http://wigglit.ath.cx/slackware_botl....log.28Jan2005
which is a blog ... hunting for entries about get-printers, I end up with screeds about setting up a cups printer server,
but learned what the conf file was ...

/etc/dbus-1/system.d/CUPS.conf

Code:

<!DOCTYPE busconfig PUBLIC "-//freedesktop//DTD D-BUS Bus Configuration 1.0//EN"
 "http://www.freedesktop.org/standards/dbus/1.0/busconfig.dtd">
<busconfig>
  <!-- Only root can send this message -->
  <policy user="root">
    <allow send_interface="com.redhat.PrinterSpooler"/>
  </policy>

  <!-- Allow any connection to receive the message -->
  <policy context="default">
    <allow receive_interface="com.redhat.PrinterSpooler"/>
  </policy>
</busconfig>

/etc/cupsd.conf

/etc/cupsd.conf.save

still looking - but I've gotta go: 8:27pm

Simon Bridge · 05-23-2005, 05:01 AM

Had a look through cups.conf ... and read the rror logs. kept seeing browse errors. Stood awhile in uffish thought did I...

Recalled: when I deitied the /etc/hosts file, it was because the host was set to the same address as the loopback interface 127.0.0.1 ... now it is set to the local lan address - could this be it?

!!!!! YESSS !!!!!
Good grief! Perhaps I should set the browse path in the cups.conf?