CUPS: "Unable to open USB device "usb:/dev/ulpt0": Permission denied"
Lars Stokholm 25 February 2007 02:12:41
I get this error, when trying to print a test page from the CUPS web interface. I've tried to chmod g+w /dev/ulpt0, but that didn't make any difference. What's wrong?
"Unable to open USB device "usb:/dev/ulpt0": Permission denied"
The printer is a HP PSC 750xi. I've installed the hpijs port, which installed CUPS as a dependency.
Sometime on Fri, 23 Jun 2006 19:42:23 +0200, Lars Stokholm scribbled:
I get this error, when trying to print a test page from the CUPS> web interface. I've tried to chmod g+w /dev/ulpt0, but that didn't> make any difference. What's wrong?>
"Unable to open USB device "usb:/dev/ulpt0": Permission denied">
The printer is a HP PSC 750xi. I've installed the hpijs port, which> installed CUPS as a dependency.
try /dev/unlpt0
-- Dave Our business in life is not to succeed, but to continue to fail in good spirits. Robert Louis Stevenson
On 2006-06-23, DaveG <dave-ng@nospam.tld> wrote:>> I get this error, when trying to print a test page from the CUPS>> web interface. I've tried to chmod g+w /dev/ulpt0, but that didn't>> make any difference. What's wrong?>>
"Unable to open USB device "usb:/dev/ulpt0": Permission denied">>
The printer is a HP PSC 750xi. I've installed the hpijs port, which>> installed CUPS as a dependency.>
try /dev/unlpt0
I think ulpt0 is the right one (though I don't know the difference).
# dmesg | grep lpt lpt0: <Printer> on ppbus0 lpt0: Interrupt-driven port ulpt0: Hewlett-Packard PSC 750xi, rev 1.10/1.00, addr 3, iclass 7/1 ulpt0: using bi-directional mode
Sometime on Sat, 24 Jun 2006 00:56:02 +0200, Lars Stokholm scribbled:
On 2006-06-23, DaveG <dave-ng@nospam.tld> wrote:>>> I get this error, when trying to print a test page from the CUPS>>> web interface. I've tried to chmod g+w /dev/ulpt0, but that didn't>>> make any difference. What's wrong?>>>
"Unable to open USB device "usb:/dev/ulpt0": Permission denied">>>
The printer is a HP PSC 750xi. I've installed the hpijs port, which>>> installed CUPS as a dependency.>>
try /dev/unlpt0>
I think ulpt0 is the right one (though I don't know the difference).
According to man ulpt
/dev/ulpt? device with reset /dev/unlpt? device without reset
On 2006-06-23, DaveG <dave-ng@nospam.tld> wrote:> >>> I get this error, when trying to print a test page from the CUPS> >>> web interface. I've tried to chmod g+w /dev/ulpt0, but that didn't> >>> make any difference. What's wrong?> >>>
"Unable to open USB device "usb:/dev/ulpt0": Permission denied"> >>>
The printer is a HP PSC 750xi. I've installed the hpijs port, which> >>> installed CUPS as a dependency.
Same here, with a Lexmark E232 which used to work prior to the cups update to 1.2.0.
I'm still looking for a solution, apparently this problem is found on all platforms...
On 2006-06-25, nicblais@hotmail.com <nicblais@hotmail.com> wrote:> Same here, with a Lexmark E232 which used to work prior to the cups> update to 1.2.0.>
I'm still looking for a solution, apparently this problem is found on> all platforms...
Good to hear that I'm not alone. If you find a solution, let us know. Of course I'll do the same.
Lars> On 2006-06-25, nicblais@hotmail.com <nicblais@hotmail.com> wrote: >> Same here, with a Lexmark E232 which used to work prior to the cups >> update to 1.2.0. >>
I'm still looking for a solution, apparently this problem is found on >> all platforms...
Lars> Good to hear that I'm not alone. If you find a solution, let us know. Lars> Of course I'll do the same.
Well, it's not really the right solution, but I set the backend (usb in my case) suid to root and then it worked. Security-wise that is certainly not the right way, but it works for me.
