Random Wisdom

Quite a few of the cheaper laser printers are difficult to use directly on Linux due to missing drivers. The reason is that quite a bit of the work is actually done by the (Windows) driver rather than the printer itself. These printers have come be known as GDI or Winprinters. The EPSON AcuLaser C1750 is such a printer. After struggling for a few days, trying to get it to work natively under Linux, I decided to look for an alternative solution [Update: see bottom of article]. Then I found one.

The basic idea is to create a dummy shared PS printer on a Windows host and then also install the physical printer there. The dummy printer accepts PS jobs from Linux clients and then filters them through Ghostscript before feeding them to the physical printer using the native Windows GDI driver. I did need to change some of the steps compared to the guide above, so I’ll provide a short guide here for others who may be looking to get their Winprinter working with Linux.

This is only a rough guide meant to give an idea of the steps required. You may need to figure out any appropriate intermediate steps and install the necessary software dependencies (e.g., samba).

Step 1: Find a networked Windows box and install the printer there
I used an instance of Windows XP running in VirtualBox on the print server itself. The networking is set to ‘Bridged’ to allow connection from others on the network.

Step 2: [Windows] Install Ghostscript, GSView and RedMon – in that order
All of the above can be found at: http://pages.cs.wisc.edu/~ghost/. I used GPL Ghostscript 9.02, GSview 5.0 and RedMon 1.7 on the Windows guest VM.

Step 3: [Windows] Configure GSprint for non-interactive printing
This is done by creating a configuration file (gsprint.cfg) in the same directory as the gsprint.exe executable. This should be in “$PATH_TO_GSVIEW”. I put the following in gsprint.cfg:

-noquery
-color
-printer
EPSON AL-C1750N

Note that each option must go on a separate line and “EPSON AL-C1750N” is the name of the printer as it appears in the Windows Control Panel. Again, note that the printer name is specified without quotes. The original guide also specifies the -ghostscript option but I found that it fails to work with that. It was best to let gsprint choose the correct Ghostscript binary automatically.

After creating the configuration file for gsprint, it is prudent to check that it functions as expected by running the following from a Windows command line:

> cd $PATH_TO_GSPRINT
> gsprint sample_ps_file.ps

The printer should now produce the sample PS file without any further input/intervention from the user.

Step 4: [Windows] Create dummy PostScript printer(s)
Use the “Add new printer” to create dummy PS printers. I created two of them — one for grayscale output and one for color. When creating the printers, choose “Local printer” and then “FILE:” as the port type. I chose the “Canon PS-IPU Color Laser Copier v52.3” as the printer model because it is a PostScript color laser printer that would allow both color and grayscale printing. The guide suggests something like the “Apple LaserWriter II NT” but that only produces grayscale output. I named the first printer “PSPrinter_BW” and the other “PSPrinter_Color”. The properties of the printer were set such that jobs sent to PSPrinter_BW are printed in grayscale while those sent to PSPrinter_Color are printed in color. Sharing is also turned on for both printers.

Step 5: [Windows] Set dummy printers to use RedMon
For each of the printers, go to “Printer properties” -> “Ports” -> “Add port”. Select “Redirected port” and click “New port”. Specify a name for the port, e.g., “RPT1:”. After adding the port, go to “Configure port” and fill out the necessary settings. For PSPrinter_Color, I have:

Redirect to program: $PATH_TO_GSPRINT.EXE
Arguments for program: -
Output: "Program handles output"
Run as user: [ ] (i.e., unchecked)

For PSPrinter_BW, I have:

Redirect to program: $PATH_TO_GSPRINT.EXE
Arguments for program: -mono -
Output: "Program handles output"
Run as user: [ ] (i.e., unchecked)

Click “OK” and close the printer properties dialog. Check that the port redirection works by printing something to PSPrinter_* and collecting the output from the physical printer.

Step 6: [Linux] Add share dummy printers to Linux
Using the printer administration module, add the shared PS printer(s) as “Windows Printer via SAMBA”. For the printer model/driver, I chose “Generic” -> “PostScript Printer”.

That’s it! It should now be possible to print to the physical printer from Linux by sending the job to the printer created in Step 6.

Update [18 July, 2012]: The EPSON AL-C1750N appears to work with the Linux drivers for the Xerox Phaser 6000. On 64bit Centos 6 it was also necessary to install the 32bit version of cups-libs. This was pointed out by Lathrop in the comments.

Up until now I have been using the ‘convert‘ tool that comes with ImageMagick to switch between image formats — mainly for creating EPS files from JPG/PNG (raster format) files for use with LaTeX. Then I came across sam2p.

It is a light-weight utility that does one thing only and it does it well: convert between image formats. I’ve been using it for a while now and find that it can greatly reduce files sizes with minimal drop in quality. I’ve even used it to process existing EPS files just to get the reduction in file size. Best of all, it is multi-platform — executables are available for both Windows and Linux on the project homepage.

Goodbye convert and hello sam2p!

Recently, I needed to use Umbrello but didn’t have access to a workstation that had it installed. And since I’m stuck with a Windows PC, I thought I’d take a look at the KDE-Cygwin project. It seems that they’ve stopped working on the project since there is a better alternative: Cooperative Linux. It’s basically a modified Linux 2.6.10 kernel that runs on Windows — kind of a like a virtual machine but it’s different — it’s definitely a lot faster. Here’s a snippet from the coLinux homepage:

Cooperative Linux is the first working free and open source method for optimally running Linux on Microsoft Windows natively. More generally, Cooperative Linux (short-named coLinux) is a port of the Linux kernel that allows it to run cooperatively alongside another operating system on a single machine. For instance, it allows one to freely run Linux on Windows 2000/XP, without using a commercial PC virtualization software such as VMware, in a way which is much more optimal than using any general purpose PC virtualization software.

The project page had a preconfigured Debian image and so that’s what I’m using at the moment. The native X server does not work though — so the Cygwin based X server is needed to diplay all the GUI stuff.

Getting it installed was a piece of cake. The Wiki site for coLinux has a lot of helpful info.

Once the basic text-mode linux is up and running (must be able to reach the host via the network), we need to run some commands from the cygwin shell. First run

$ cygserver-config

to configure the cygwin server and then start the server with:

$ cygrunserver -S cygserver

Then, we need to set

$ export CYGWIN=server

And then start the X server in rootless mode. The easiest way is to just make a copy of the startxwin.bat file and then edit it to change the options to XWin.

Once the X server is running, we need to run “xhost +” from the xterm that had popped up. Then, we switch over to the coLinux console and run:

$ export DISPLAY=<ip of windows host>:0

And that’s it! Now you have a fully functional linux distro! I would have gone for a Fedora install but couldn’t find a proper image.

Thus starts my first day at work. I’ve already got 2 papers to read and a meeting scheduled for later today. Got a brand new computer (HP Compaq DC5100) running only Win XP :(. For the kind of work I’ll be doing (software development), I would have liked a *nix based machine. Apparently the simulation workstations are *nix so I’ll have to make do with Xwin32 for the next 6 months.

Well .. at least I still have my own PC which should become net active again sometime after next weekend.

Alright then, back to my reading. Good luck to me! 🙂

Piece of cake; before clicking “Express” or “Custom” paste the following in the addressbar and hit enter:

javascript:void(window.g_sDisableWGACheck='all')

Got this tip from here.