Suramya's Blog : Welcome to my crazy life…

A couple of days ago I decided to try hooking up my LCD TV to my computer to see if I could use it as an extra monitor (that didn’t work that well because the TV was too big to be comfortable but that is a different story). So while I was connecting the TV over HDMI I also installed the proprietary drivers for my RADEON HD 4250 card (and promptly forgot about doing this).

Didn’t like working with the TV (too big, too close) so put it back and then noticed that my panel was no longer translucent and none of the desktop effects were working. Ignored it for a couple of days and then decided to fix the issue.

Tried disabling and enabling the Desktop effects from the Settings -> Desktop Effects but I kept getting and error stating that the effects could not be activated and that I should check my Xorg.conf for errors. Tried searching for the Xorg.conf file but that file doesn’t exist on my system so was stumped.

Ignored the issue for another day or so but then got irritated enough today to try and fix it again. Searched online for a fix and found some tips, some bug reports but nothing that worked. Then I found a page where this person was asking if the Opensource driver is better than the propitiatory one. This tickled my brain cells and I had a hazy memory of installing the other version, so decided to take a chance and uninstall the propitiatory version and re-install the Opensource version.

Used the following commands to do this:

  apt-get remove --purge fglrx*
  apt-get remove --purge xserver-xorg-video-ati xserver-xorg-video-radeon 
  apt-get install xserver-xorg-video-ati
  apt-get install --reinstall libgl1-mesa-glx libgl1-mesa-dri xserver-xorg-core
  dpkg-reconfigure xserver-xorg

After doing this I restarted my system (had to do it anyways) and got my desktop effects back. Yay me!

Thanks to wiki.Unbuntu.org for the steps to purge the propitiatory driver.

Hope someone else also finds this useful sometime.

-Suramya

Its happened to me twice so far that when I try to print to my HP Deskjet F380 the job just sits in the print queue and is apparently on hold. Canceling the job and printing again doesn’t fix the problem and when I hook up the printer to another system it works fine.

The problem is that the printer has been ‘disabled’ for some reason on the system. I think that this happens when you are printing something and you switch off the printer in the middle but haven’t confirmed that yet.

To fix it you need to ‘Enable’ the printer. There are two ways you can do this:

Using the Printer Configuration GUI

1. Run the ‘system-config-printer’ GUI via Start -> system -> Printing or from the command prompt.
2. Right click on the printer
3. Click on ‘Enable’ in the drop down menu.

That’s it. Now the queued print jobs should start processing again.

The other method is using the CUPS Web interface

1. Login to the CUPS interface at: http://localhost:631/
2. Click on the ‘Printers’ tab
3. Click on the Printer that is having issues from the list on the page
4. Click on the ‘Maintainence’ Drop box
5. Select ‘Resume Printer’

You should get a message like: “Printer Deskjet_F300_series has been resumed. and you are done.

Hope this helps someone.

– Suramya

Figuring out if the input to a script is coming from the terminal or from a pipe is not something that I have ever had to use but I found the possibility very interesting so sharing it over here:

#!/bin/bash

stdin="$(ls -l /dev/fd/0)"
stdin="${stdin/*-> /}"
ftype="$(stat --printf=%F $stdin)"

if   [[ "$ftype" == 'character special file' ]]; then 
	echo Terminal
elif [[ "$ftype" == 'regular file' ]]; then 
	echo Pipe: $stdin
else
	echo Unknown: $stdin
fi

– Suramya

Source: Linux Journal

One of the things I liked about KDE3.5 and KDE4 on Ubuntu was that the mouse cursor was this translucent arrow which looked a lot better than the default one on Windows. When I switched to Debian for some reason I didn’t have that theme installed by default. So I tried searching for it but couldn’t find the theme as its kind of hard to search for translucent cursor in kde and get sensible results.

Today I decided to search again and found this forum post about customizing Ubuntu. Over there he mentioned the names of the the cursor themes installed on Ubuntu. Using that as a base I did some more digging/searching and finally found the name of the package I had to install to get my translucent cursor back.

The package you have to install is called ‘xcursor-themes’ and the theme I needed is called ‘whiteglass’. On Debian you can install it by issuing the following command: apt-get install xcursor-themes

Hope this helps.

– Suramya

I have a HP Deskjet F380 All-in-One scanner/printer/copier systems and it is a great machine. I plugged it into my system and started GIMP to scan an image from it. Within about 20 seconds of me powering on the printer I got a popup message in Gimp telling me that my HP printer is ready for use. I printed a test page and it came out fine.

Then I tried to scan an image and I got a message back from SANE that it didn’t find any devices. Checked the system log in /var/log/system and noticed the following error message in the log:

Dec 28 13:36:04 Wyrm python: io/hpmud/musb.c 136: unable get_string_descriptor -1: Operation not permitted
Dec 28 13:36:04 Wyrm python: io/hpmud/musb.c 603: invalid product id string ret=-1

Did a search on the net about the error message and in one of the forums it suggested that I run hp-check to see if I was missing any of the required files. The program gave me a list of missing dependencies that I installed. But the problem still wasn’t solved.

While searching for a solution I found a post on a forum that stated that this person was able to scan an image when running as root but not as a regular user. So I decided to try running xsane as root. When I did that the program ran successfully and detected my scanner. I was also able to scan an image without any issues.

However since its not a good idea to run programs as root, I needed a permanent fix. The same forum gave me a not so elegant but permanent solution to try.

To fix the problem run lsusb and locate the line containing your printer information. On my system the output of the command is:

Bus 002 Device 002: ID 046e:556a Behavior Tech. Computer Corp.
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 001 Device 009: ID 03f0:5511 Hewlett-Packard DeskJet F300 series
Bus 001 Device 004: ID 0a12:0001 Cambridge Silicon Radio, Ltd Bluetooth Dongle (HCI mode)
Bus 001 Device 003: ID 05e3:0608 Genesys Logic, Inc. USB-2.0 4-Port HUB
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

As you can see the third line gives the the information for my Printer. Now we need to get the vendor and product ID for the printer. The first set of alphanumeric after the ID is the Vendor ID and the numbers after the ‘:’ denote the Product ID. In my case the ‘Vendor ID’ = 03f0 and the ‘Product ID’ = 5511.

Once we have that information we need to create a new file as root at ‘/etc/udev/rules.d/99-custom.rules‘ with the following content:

ATTR{idVendor}==”VendorID”, ATTR{idProduct}==”ProductID”, MODE=”0666″, GROUP=”lp”

where the ProductID and VendorID are the values we got earlier. Once you make the changes, save the file. Then you can disconnect the printer and reconnect it for the new changes to take effect and your scanner will be ready for use.

Another approach which could have worked was to add the user scanning the image to the group ‘lp’ and ‘scanner’ to give them access to the printer. Keep in mind that I haven’t really tried this approach yet

Thanks to Meson at LinuxQuestions.org for the steps to make the printer accessible to all users.

Hope this helps.

– Suramya